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[cgroup/for-6.20 PATCH 0/4] cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict

by Waiman Long

This patch series is inspired by the cpuset patch sent by Sun Shaojie [1]. The idea is to avoid invalidating sibling partitions when there is a cpuset.cpus conflict. However this patch series does it in a slightly different way to make its behavior more consistent with other cpuset properties. The first 3 patches are just some cleanup and minor bug fixes on issues found during the investigation process. The last one is the major patch that changes the way cpuset.cpus is being handled during the partition creation process. Instead of invalidating sibling partitions when there is a conflict, it will strip out the conflicting exclusive CPUs and assign the remaining non-conflicting exclusive CPUs to the new partition unless there is no more CPU left which will fail the partition creation process. It is similar to the idea that cpuset.cpus.effective may only contain a subset of CPUs specified in cpuset.cpus. So cpuset.cpus.exclusive.effective may contain only a subset of cpuset.cpus when a partition is created without setting cpuset.cpus.exclusive. Even setting cpuset.cpus.exclusive instead of cpuset.cpus may not guarantee all the requested CPUs can be granted if parent doesn't have access to some of those exclusive CPUs. The difference is that conflicts from siblings is not possible with cpuset.cpus.exclusive as long as it can be set successfully without failure. [1] https://lore.kernel.org/lkml/20251117015708.977585-1-sunshaojie@kylinos.cn/ Waiman Long (4): cgroup/cpuset: Streamline rm_siblings_excl_cpus() cgroup/cpuset: Consistently compute effective_xcpus in update_cpumasks_hier() cgroup/cpuset: Don't fail cpuset.cpus change in v2 cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict kernel/cgroup/cpuset-internal.h | 3 + kernel/cgroup/cpuset-v1.c | 19 +++ kernel/cgroup/cpuset.c | 135 +++++++----------- .../selftests/cgroup/test_cpuset_prs.sh | 26 +++- 4 files changed, 93 insertions(+), 90 deletions(-) -- 2.52.0

2 weeks, 1 day

4
13
0 0

[PATCH v8 00/14] riscv: add SBI FWFT misaligned exception delegation support

by Clément Léger

The SBI Firmware Feature extension allows the S-mode to request some specific features (either hardware or software) to be enabled. This series uses this extension to request misaligned access exception delegation to S-mode in order to let the kernel handle it. It also adds support for the KVM FWFT SBI extension based on the misaligned access handling infrastructure. FWFT SBI extension is part of the SBI V3.0 specifications [1]. It can be tested using the qemu provided at [2] which contains the series from [3]. Upstream kvm-unit-tests can be used inside kvm to tests the correct delegation of misaligned exceptions. Upstream OpenSBI can be used. Note: Since SBI V3.0 is not yet ratified, FWFT extension API is split between interface only and implementation, allowing to pick only the interface which do not have hard dependencies on SBI. The tests can be run using the kselftest from series [4]. $ qemu-system-riscv64 \ -cpu rv64,trap-misaligned-access=true,v=true \ -M virt \ -m 1024M \ -bios fw_dynamic.bin \ -kernel Image ... # ./misaligned TAP version 13 1..23 # Starting 23 tests from 1 test cases. # RUN global.gp_load_lh ... # OK global.gp_load_lh ok 1 global.gp_load_lh # RUN global.gp_load_lhu ... # OK global.gp_load_lhu ok 2 global.gp_load_lhu # RUN global.gp_load_lw ... # OK global.gp_load_lw ok 3 global.gp_load_lw # RUN global.gp_load_lwu ... # OK global.gp_load_lwu ok 4 global.gp_load_lwu # RUN global.gp_load_ld ... # OK global.gp_load_ld ok 5 global.gp_load_ld # RUN global.gp_load_c_lw ... # OK global.gp_load_c_lw ok 6 global.gp_load_c_lw # RUN global.gp_load_c_ld ... # OK global.gp_load_c_ld ok 7 global.gp_load_c_ld # RUN global.gp_load_c_ldsp ... # OK global.gp_load_c_ldsp ok 8 global.gp_load_c_ldsp # RUN global.gp_load_sh ... # OK global.gp_load_sh ok 9 global.gp_load_sh # RUN global.gp_load_sw ... # OK global.gp_load_sw ok 10 global.gp_load_sw # RUN global.gp_load_sd ... # OK global.gp_load_sd ok 11 global.gp_load_sd # RUN global.gp_load_c_sw ... # OK global.gp_load_c_sw ok 12 global.gp_load_c_sw # RUN global.gp_load_c_sd ... # OK global.gp_load_c_sd ok 13 global.gp_load_c_sd # RUN global.gp_load_c_sdsp ... # OK global.gp_load_c_sdsp ok 14 global.gp_load_c_sdsp # RUN global.fpu_load_flw ... # OK global.fpu_load_flw ok 15 global.fpu_load_flw # RUN global.fpu_load_fld ... # OK global.fpu_load_fld ok 16 global.fpu_load_fld # RUN global.fpu_load_c_fld ... # OK global.fpu_load_c_fld ok 17 global.fpu_load_c_fld # RUN global.fpu_load_c_fldsp ... # OK global.fpu_load_c_fldsp ok 18 global.fpu_load_c_fldsp # RUN global.fpu_store_fsw ... # OK global.fpu_store_fsw ok 19 global.fpu_store_fsw # RUN global.fpu_store_fsd ... # OK global.fpu_store_fsd ok 20 global.fpu_store_fsd # RUN global.fpu_store_c_fsd ... # OK global.fpu_store_c_fsd ok 21 global.fpu_store_c_fsd # RUN global.fpu_store_c_fsdsp ... # OK global.fpu_store_c_fsdsp ok 22 global.fpu_store_c_fsdsp # RUN global.gen_sigbus ... [12797.988647] misaligned[618]: unhandled signal 7 code 0x1 at 0x0000000000014dc0 in misaligned[4dc0,10000+76000] [12797.988990] CPU: 0 UID: 0 PID: 618 Comm: misaligned Not tainted 6.13.0-rc6-00008-g4ec4468967c9-dirty #51 [12797.989169] Hardware name: riscv-virtio,qemu (DT) [12797.989264] epc : 0000000000014dc0 ra : 0000000000014d00 sp : 00007fffe165d100 [12797.989407] gp : 000000000008f6e8 tp : 0000000000095760 t0 : 0000000000000008 [12797.989544] t1 : 00000000000965d8 t2 : 000000000008e830 s0 : 00007fffe165d160 [12797.989692] s1 : 000000000000001a a0 : 0000000000000000 a1 : 0000000000000002 [12797.989831] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffffdeadbeef [12797.989964] a5 : 000000000008ef61 a6 : 626769735f6e0000 a7 : fffffffffffff000 [12797.990094] s2 : 0000000000000001 s3 : 00007fffe165d838 s4 : 00007fffe165d848 [12797.990238] s5 : 000000000000001a s6 : 0000000000010442 s7 : 0000000000010200 [12797.990391] s8 : 000000000000003a s9 : 0000000000094508 s10: 0000000000000000 [12797.990526] s11: 0000555567460668 t3 : 00007fffe165d070 t4 : 00000000000965d0 [12797.990656] t5 : fefefefefefefeff t6 : 0000000000000073 [12797.990756] status: 0000000200004020 badaddr: 000000000008ef61 cause: 0000000000000006 [12797.990911] Code: 8793 8791 3423 fcf4 3783 fc84 c737 dead 0713 eef7 (c398) 0001 # OK global.gen_sigbus ok 23 global.gen_sigbus # PASSED: 23 / 23 tests passed. # Totals: pass:23 fail:0 xfail:0 xpass:0 skip:0 error:0 With kvm-tools: # lkvm run -k sbi.flat -m 128 Info: # lkvm run -k sbi.flat -m 128 -c 1 --name guest-97 Info: Removed ghost socket file "/root/.lkvm//guest-97.sock". ########################################################################## # kvm-unit-tests ########################################################################## ... [test messages elided] PASS: sbi: fwft: FWFT extension probing no error PASS: sbi: fwft: get/set reserved feature 0x6 error == SBI_ERR_DENIED PASS: sbi: fwft: get/set reserved feature 0x3fffffff error == SBI_ERR_DENIED PASS: sbi: fwft: get/set reserved feature 0x80000000 error == SBI_ERR_DENIED PASS: sbi: fwft: get/set reserved feature 0xbfffffff error == SBI_ERR_DENIED PASS: sbi: fwft: misaligned_deleg: Get misaligned deleg feature no error PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature invalid value error PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature invalid value error PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature value no error PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature value 0 PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature value no error PASS: sbi: fwft: misaligned_deleg: Set misaligned deleg feature value 1 PASS: sbi: fwft: misaligned_deleg: Verify misaligned load exception trap in supervisor SUMMARY: 50 tests, 2 unexpected failures, 12 skipped This series is available at [5]. Link: https://github.com/riscv-non-isa/riscv-sbi-doc/releases/download/vv3.0-rc2/… [1] Link: https://github.com/rivosinc/qemu/tree/dev/cleger/misaligned [2] Link: https://lore.kernel.org/all/20241211211933.198792-3-fkonrad@amd.com/T/ [3] Link: https://lore.kernel.org/linux-riscv/20250414123543.1615478-1-cleger@rivosin… [4] Link: https://github.com/rivosinc/linux/tree/dev/cleger/fwft [5] --- V8: - Move misaligned_access_speed under CONFIG_RISCV_MISALIGNED and add a separate commit for that. V7: - Fix ifdefery build problems - Move sbi_fwft_is_supported with fwft_set_req struct - Added Atish Reviewed-by - Updated KVM vcpu cfg hedeleg value in set_delegation - Changed SBI ETIME error mapping to ETIMEDOUT - Fixed a few typo reported by Alok V6: - Rename FWFT interface to remove "_local" - Fix test for MEDELEG values in KVM FWFT support - Add __init for unaligned_access_init() - Rebased on master V5: - Return ERANGE as mapping for SBI_ERR_BAD_RANGE - Removed unused sbi_fwft_get() - Fix kernel for sbi_fwft_local_set_cpumask() - Fix indentation for sbi_fwft_local_set() - Remove spurious space in kvm_sbi_fwft_ops. - Rebased on origin/master - Remove fixes commits and sent them as a separate series [4] V4: - Check SBI version 3.0 instead of 2.0 for FWFT presence - Use long for kvm_sbi_fwft operation return value - Init KVM sbi extension even if default_disabled - Remove revert_on_fail parameter for sbi_fwft_feature_set(). - Fix comments for sbi_fwft_set/get() - Only handle local features (there are no globals yet in the spec) - Add new SBI errors to sbi_err_map_linux_errno() V3: - Added comment about kvm sbi fwft supported/set/get callback requirements - Move struct kvm_sbi_fwft_feature in kvm_sbi_fwft.c - Add a FWFT interface V2: - Added Kselftest for misaligned testing - Added get_user() usage instead of __get_user() - Reenable interrupt when possible in misaligned access handling - Document that riscv supports unaligned-traps - Fix KVM extension state when an init function is present - Rework SBI misaligned accesses trap delegation code - Added support for CPU hotplugging - Added KVM SBI reset callback - Added reset for KVM SBI FWFT lock - Return SBI_ERR_DENIED_LOCKED when LOCK flag is set Clément Léger (14): riscv: sbi: add Firmware Feature (FWFT) SBI extensions definitions riscv: sbi: remove useless parenthesis riscv: sbi: add new SBI error mappings riscv: sbi: add FWFT extension interface riscv: sbi: add SBI FWFT extension calls riscv: misaligned: request misaligned exception from SBI riscv: misaligned: use on_each_cpu() for scalar misaligned access probing riscv: misaligned: declare misaligned_access_speed under CONFIG_RISCV_MISALIGNED riscv: misaligned: move emulated access uniformity check in a function riscv: misaligned: add a function to check misalign trap delegability RISC-V: KVM: add SBI extension init()/deinit() functions RISC-V: KVM: add SBI extension reset callback RISC-V: KVM: add support for FWFT SBI extension RISC-V: KVM: add support for SBI_FWFT_MISALIGNED_DELEG arch/riscv/include/asm/cpufeature.h | 14 +- arch/riscv/include/asm/kvm_host.h | 5 +- arch/riscv/include/asm/kvm_vcpu_sbi.h | 12 + arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h | 29 +++ arch/riscv/include/asm/sbi.h | 60 +++++ arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kernel/sbi.c | 81 ++++++- arch/riscv/kernel/traps_misaligned.c | 112 ++++++++- arch/riscv/kernel/unaligned_access_speed.c | 8 +- arch/riscv/kvm/Makefile | 1 + arch/riscv/kvm/vcpu.c | 4 +- arch/riscv/kvm/vcpu_sbi.c | 54 +++++ arch/riscv/kvm/vcpu_sbi_fwft.c | 257 +++++++++++++++++++++ arch/riscv/kvm/vcpu_sbi_sta.c | 3 +- 14 files changed, 620 insertions(+), 21 deletions(-) create mode 100644 arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h create mode 100644 arch/riscv/kvm/vcpu_sbi_fwft.c -- 2.49.0

2 weeks, 2 days

10
40
0 0

[PATCH RESEND] selftests/powerpc/pmu/: Add check_extended_reg_test to .gitignore

by Gopi Krishna Menon

Add the check_extended_reg_test binary to .gitignore to avoid accidentally staging the build artifact. Signed-off-by: Gopi Krishna Menon <krishnagopi487(a)gmail.com> --- tools/testing/selftests/powerpc/pmu/sampling_tests/.gitignore | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/powerpc/pmu/sampling_tests/.gitignore b/tools/testing/selftests/powerpc/pmu/sampling_tests/.gitignore index f93b4c7c3a8a..ea29228334e8 100644 --- a/tools/testing/selftests/powerpc/pmu/sampling_tests/.gitignore +++ b/tools/testing/selftests/powerpc/pmu/sampling_tests/.gitignore @@ -1,5 +1,6 @@ bhrb_filter_map_test bhrb_no_crash_wo_pmu_test +check_extended_reg_test intr_regs_no_crash_wo_pmu_test mmcr0_cc56run_test mmcr0_exceptionbits_test -- 2.43.0

2 weeks, 3 days

3
2
0 0

[PATCH] selftests/tracing: Fix test_multiple_writes stall

by Fushuai Wang

When /sys/kernel/tracing/buffer_size_kb is less than 12KB, the test_multiple_writes test will stall and wait for more input due to insufficient buffer space. This patch check current buffer_size_kb value before the test. If it is less than 12KB, it temporarily increase the buffer to 12KB, and restore the original value after the tests are completed. Fixes: 37f46601383a ("selftests/tracing: Add basic test for trace_marker_raw file") Signed-off-by: Fushuai Wang <wangfushuai(a)baidu.com> --- .../ftrace/test.d/00basic/trace_marker_raw.tc | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc b/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc index 7daf7292209e..216f87d89c3f 100644 --- a/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc +++ b/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc @@ -58,7 +58,7 @@ test_multiple_writes() { echo stop > trace_marker # Check to make sure the number of entries is the id (rounded up by 4) - awk '/.*: # [0-9a-f]* / { + awk -v ORIG="${ORIG}" '/.*: # [0-9a-f]* / { print; cnt = -1; for (i = 0; i < NF; i++) { @@ -70,6 +70,7 @@ test_multiple_writes() { # The number of items is always rounded up by 4 cnt2 = int((cnt + 3) / 4) * 4; if (cnt2 != num) { + system("echo \""ORIG"\" > buffer_size_kb"); exit 1; } break; @@ -89,6 +90,7 @@ test_buffer() { # The id must be four bytes, test that 3 bytes fails a write if echo -n abc > ./trace_marker_raw ; then echo "Too small of write expected to fail but did not" + echo $ORIG > buffer_size_kb exit_fail fi @@ -99,9 +101,21 @@ test_buffer() { if write_buffer 0xdeadbeef $size ; then echo "Too big of write expected to fail but did not" + echo $ORIG > buffer_size_kb exit_fail fi } +ORIG=`cat buffer_size_kb` + +# test_multiple_writes test needs at least 12KB buffer +NEW_SIZE=12 + +if [ ${ORIG} -lt ${NEW_SIZE} ]; then + echo ${NEW_SIZE} > buffer_size_kb +fi + test_buffer test_multiple_writes + +echo $ORIG > buffer_size_kb -- 2.36.1

2 weeks, 3 days

2
2
0 0

[PATCH 00/20] ublk: add support for integrity data

by Caleb Sander Mateos

Much work has recently gone into supporting block device integrity data (sometimes called "metadata") in Linux. Many NVMe devices these days support metadata transfers and/or automatic protection information generation and verification. However, ublk devices can't yet advertise integrity data capabilities. This patch series wires up support for integrity data in ublk. The ublk feature is referred to as "integrity" rather than "metadata" to match the block layer's name for it and to avoid confusion with the existing and unrelated UBLK_IO_F_META. To advertise support for integrity data, a ublk server fills out the struct ublk_params's integrity field and sets UBLK_PARAM_TYPE_INTEGRITY. The struct ublk_param_integrity flags and csum_type fields use the existing LBMD_PI_* constants from the linux/fs.h UAPI header. The ublk driver fills out a corresponding struct blk_integrity. When a request with integrity data is issued to the ublk device, the ublk driver sets UBLK_IO_F_INTEGRITY in struct ublksrv_io_desc's op_flags field. This is necessary for a ublk server for which bi_offload_capable() returns true to distinguish requests with integrity data from those without. Integrity data transfers can currently only be performed via the ublk user copy mechanism. The overhead of zero-copy buffer registration makes it less appealing for the small transfers typical of integrity data. Additionally, neither io_uring NVMe passthru nor IORING_RW_ATTR_FLAG_PI currently allow an io_uring registered buffer for the integrity data. The ki_pos field of the struct kiocb passed to the user copy ->{read,write}_iter() callback gains a bit UBLKSRV_IO_INTEGRITY_FLAG for a ublk server to indicate whether to access the request's data or integrity data. Not yet supported is an analogue for the IO_INTEGRITY_CHK_*/BIP_CHECK_* flags to ask the ublk server to verify the guard, reftag, and/or apptag of a request's protection information. The user copy mechanism currently forbids a ublk server from reading the data/integrity buffer of a read-direction request. We could potentially relax this restriction for integrity data on reads. Alternatively, the ublk driver could verify the requested fields as part of the user copy operation. The first 2 commits harden blk_validate_integrity_limits() to reject nonsensical pi_offset and interval_exp integrity limits. Caleb Sander Mateos (17): block: validate pi_offset integrity limit block: validate interval_exp integrity limit blk-integrity: take const pointer in blk_integrity_rq() ublk: move ublk flag check functions earlier ublk: set UBLK_IO_F_INTEGRITY in ublksrv_io_desc ublk: add ublk_copy_user_bvec() helper ublk: split out ublk_user_copy() helper ublk: inline ublk_check_and_get_req() into ublk_user_copy() ublk: move offset check out of __ublk_check_and_get_req() ublk: optimize ublk_user_copy() on daemon task selftests: ublk: add utility to get block device metadata size selftests: ublk: add kublk support for integrity params selftests: ublk: implement integrity user copy in kublk selftests: ublk: support non-O_DIRECT backing files selftests: ublk: add integrity data support to loop target selftests: ublk: add integrity params test selftests: ublk: add end-to-end integrity test Stanley Zhang (3): ublk: add integrity UAPI ublk: support UBLK_PARAM_TYPE_INTEGRITY in device creation ublk: implement integrity user copy block/blk-settings.c | 14 +- drivers/block/ublk_drv.c | 336 +++++++++++++------ include/linux/blk-integrity.h | 6 +- include/uapi/linux/ublk_cmd.h | 20 +- tools/testing/selftests/ublk/Makefile | 6 +- tools/testing/selftests/ublk/common.c | 4 +- tools/testing/selftests/ublk/fault_inject.c | 1 + tools/testing/selftests/ublk/file_backed.c | 61 +++- tools/testing/selftests/ublk/kublk.c | 85 ++++- tools/testing/selftests/ublk/kublk.h | 37 +- tools/testing/selftests/ublk/metadata_size.c | 37 ++ tools/testing/selftests/ublk/null.c | 1 + tools/testing/selftests/ublk/stripe.c | 6 +- tools/testing/selftests/ublk/test_common.sh | 10 + tools/testing/selftests/ublk/test_loop_08.sh | 111 ++++++ tools/testing/selftests/ublk/test_null_04.sh | 166 +++++++++ 16 files changed, 765 insertions(+), 136 deletions(-) create mode 100644 tools/testing/selftests/ublk/metadata_size.c create mode 100755 tools/testing/selftests/ublk/test_loop_08.sh create mode 100755 tools/testing/selftests/ublk/test_null_04.sh -- 2.45.2

2 weeks, 4 days

4
39
0 0

[PATCH v3 0/1] cpuset: relax the overlap check for cgroup-v2

by Sun Shaojie

In cgroup v2, a mutual overlap check is required when at least one of two cpusets is exclusive. However, this check should be relaxed and limited to cases where both cpusets are exclusive. This patch ensures that for sibling cpusets A1 (exclusive) and B1 (non-exclusive), change B1 cannot affect A1's exclusivity. for example. Assume a machine has 4 CPUs (0-3). root cgroup / \ A1 B1 Case 1: Table 1.1: Before applying the patch Step | A1's prstate | B1'sprstate | #1> echo "0-1" > A1/cpuset.cpus | member | member | #2> echo "root" > A1/cpuset.cpus.partition | root | member | #3> echo "0" > B1/cpuset.cpus | root invalid | member | After step #3, A1 changes from "root" to "root invalid" because its CPUs (0-1) overlap with those requested by B1 (0-3). However, B1 can actually use CPUs 2-3(from B1's parent), so it would be more reasonable for A1 to remain as "root." Table 1.2: After applying the patch Step | A1's prstate | B1'sprstate | #1> echo "0-1" > A1/cpuset.cpus | member | member | #2> echo "root" > A1/cpuset.cpus.partition | root | member | #3> echo "0" > B1/cpuset.cpus | root | member | Case 2: (This situation remains unchanged from before) Table 2.1: Before applying the patch Step | A1's prstate | B1'sprstate | #1> echo "0-1" > A1/cpuset.cpus | member | member | #3> echo "1-2" > B1/cpuset.cpus | member | member | #2> echo "root" > A1/cpuset.cpus.partition | root invalid | member | Table 2.2: After applying the patch Step | A1's prstate | B1'sprstate | #1> echo "0-1" > A1/cpuset.cpus | member | member | #3> echo "1-2" > B1/cpuset.cpus | member | member | #2> echo "root" > A1/cpuset.cpus.partition | root invalid | member | All other cases remain unaffected. For example, cgroup-v1, both A1 and B1 are exclusive or non-exlusive. --- v3 -> v4: - Adjust the test_cpuset_prt.sh test file to align with the current behavior. v2 -> v3: - Ensure compliance with constraints such as cpuset.cpus.exclusive. - Link: https://lore.kernel.org/cgroups/20251113131434.606961-1-sunshaojie@kylinos.… v1 -> v2: - Keeps the current cgroup v1 behavior unchanged - Link: https://lore.kernel.org/cgroups/c8e234f4-2c27-4753-8f39-8ae83197efd3@redhat… --- kernel/cgroup/cpuset-internal.h | 3 ++ kernel/cgroup/cpuset-v1.c | 20 +++++++++ kernel/cgroup/cpuset.c | 43 ++++++++++++++----- .../selftests/cgroup/test_cpuset_prs.sh | 5 ++- 4 files changed, 58 insertions(+), 13 deletions(-) -- 2.25.1

2 weeks, 5 days

4
51
0 0

[PATCH 0/2] vfio: selftests: Clean up <uapi/linux/types.h> includes

by David Matlack

Small clean up series to eliminate the extra includes of <uapi/linux/types.h> from various VFIO selftests files. This include is not causing any problems now, but it is causing benign typedef redifinitions. Those redifinitions will become a problem when the VFIO selftests library is built into KVM selftests, since KVM selftests build with -std=gnu99. Cc: Yosry Ahmed <yosryahmed(a)google.com> Cc: Josh Hilke <jrhilke(a)google.com> David Matlack (2): tools include: Add definitions for __aligned_{l,b}e64 vfio: selftests: Drop <uapi/linux/types.h> includes tools/include/linux/types.h | 8 ++++++++ .../selftests/vfio/lib/include/libvfio/iova_allocator.h | 1 - tools/testing/selftests/vfio/lib/iommu.c | 1 - tools/testing/selftests/vfio/lib/iova_allocator.c | 1 - tools/testing/selftests/vfio/lib/vfio_pci_device.c | 1 - tools/testing/selftests/vfio/vfio_dma_mapping_test.c | 1 - tools/testing/selftests/vfio/vfio_iommufd_setup_test.c | 1 - 7 files changed, 8 insertions(+), 6 deletions(-) base-commit: d721f52e31553a848e0e9947ca15a49c5674aef3 -- 2.52.0.322.g1dd061c0dc-goog

2 weeks, 6 days

2
3
0 0

[PATCH v2 0/3] bitmap: convert self-test to KUnit

by Tamir Duberstein

This is the last remaining "Test Module" kselftest, the rest having been converted to KUnit. Relative to v1 this keeps benchmarks out of KUnit in light of Yury's concerns: On Sat, Feb 8, 2025 at 12:53 PM Yury Norov <yury.norov(a)gmail.com> wrote: > > [...] > > This is my evidence: sometimes people report performance or whatever > issues on their systems, suspecting bitmaps guilty. I ask them to run > the bitmap or find_bit test to narrow the problem. Sometimes I need to > test a hardware I have no access to, and I have to (kindly!) ask people > to build a small test and run it. I don't want to ask them to rebuild > the whole kernel, or even to build something else. > > https://lore.kernel.org/all/YuWk3titnOiQACzC@yury-laptop/ I tested this using: $ tools/testing/kunit/kunit.py run --arch arm64 --make_options LLVM=1 bitmap There was a previous attempt[2] to do this in July 2024. Please bear with me as I try to understand and address the objections from that time. I've spoken with Muhammad Usama Anjum, the author of that series, and received their approval to "take over" this work. Here we go... On 7/26/24 11:45 PM, John Hubbard wrote: > > This changes the situation from "works for Linus' tab completion > case", to "causes a tab completion problem"! :) > > I think a tests/ subdir is how we eventually decided to do this [1], > right? > > So: > > lib/tests/bitmap_kunit.c > > [1] https://lore.kernel.org/20240724201354.make.730-kees@kernel.org This is true and unfortunate, but not trivial to fix because new kallsyms tests were placed in lib/tests in commit 84b4a51fce4c ("selftests: add new kallsyms selftests") *after* the KUnit filename best practices were adopted. I propose that the KUnit maintainers blaze this trail using `string_kunit.c` which currently still lives in lib/ despite the KUnit docs giving it as an example at lib/tests/. On 7/27/24 12:24 AM, Shuah Khan wrote: > > This change will take away the ability to run bitmap tests during > boot on a non-kunit kernel. > > Nack on this change. I wan to see all tests that are being removed > from lib because they have been converted - also it doesn't make > sense to convert some tests like this one that add the ability test > during boot. This point was also discussed in another thread[3] in which: On 7/27/24 12:35 AM, Shuah Khan wrote: > > Please make sure you aren't taking away the ability to run these tests during > boot. > > It doesn't make sense to convert every single test especially when it > is intended to be run during boot without dependencies - not as a kunit test > but a regression test during boot. > > bitmap is one example - pay attention to the config help test - bitmap > one clearly states it runs regression testing during boot. Any test that > says that isn't a candidate for conversion. > > I am going to nack any such conversions. The crux of the argument seems to be that the config help text is taken to describe the author's intent with the fragment "at boot". I think this may be a case of confirmation bias: I see at least the following KUnit tests with "at boot" in their help text: - CPUMASK_KUNIT_TEST - BITFIELD_KUNIT - CHECKSUM_KUNIT - UTIL_MACROS_KUNIT It seems to me that the inference being made is that any test that runs "at boot" is intended to be run by both developers and users, but I find no evidence that bitmap in particular would ever provide additional value when run by users. There's further discussion about KUnit not being "ideal for cases where people would want to check a subsystem on a running kernel", but I find no evidence that bitmap in particular is actually testing the running kernel; it is a unit test of the bitmap functions, which is also stated in the config help text. David Gow made many of the same points in his final reply[4], which was never replied to. Link: https://lore.kernel.org/all/20250207-printf-kunit-convert-v2-0-057b23860823… [0] Link: https://lore.kernel.org/all/20250207-scanf-kunit-convert-v4-0-a23e2afaede8@… [1] Link: https://lore.kernel.org/all/20240726110658.2281070-1-usama.anjum@collabora.… [2] Link: https://lore.kernel.org/all/327831fb-47ab-4555-8f0b-19a8dbcaacd7@collabora.… [3] Link: https://lore.kernel.org/all/CABVgOSmMoPD3JfzVd4VTkzGL2fZCo8LfwzaVSzeFimPrhg… [4] Thanks for your attention. Signed-off-by: Tamir Duberstein <tamird(a)gmail.com> --- Changes in v2: - Rebase on v6.19-rc1, dropping the first patch. - Extract benchmarks into new module and deduplicate `test_bitmap_{read,write}_perf`. - Remove tc_err() and use KUnit assertions. - Parameterize `test_bitmap_cut` and `test_bitmap_parse{,list}`. - Drop KUnit boilerplate from BITMAP_KUNIT_TEST help text. - Drop arch changes. - Link to v1: https://lore.kernel.org/r/20250207-bitmap-kunit-convert-v1-0-c520675343b6@g… --- Tamir Duberstein (3): test_bitmap: extract benchmark module bitmap: convert self-test to KUnit bitmap: break kunit into test cases MAINTAINERS | 3 +- lib/Kconfig.debug | 16 +- lib/Makefile | 5 +- lib/bitmap_benchmark.c | 89 +++++ lib/{test_bitmap.c => bitmap_kunit.c} | 630 ++++++++++++++-------------------- tools/testing/selftests/lib/Makefile | 2 +- tools/testing/selftests/lib/bitmap.sh | 3 - tools/testing/selftests/lib/config | 1 - 8 files changed, 360 insertions(+), 389 deletions(-) --- base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 change-id: 20250207-bitmap-kunit-convert-92d3147b2eee Best regards, -- Tamir Duberstein <tamird(a)gmail.com>

3 weeks

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Re: [PATCH v3 1/3] selftests/mm/write_to_hugetlbfs: parse -s as size_t

by David Laight

On Mon, 22 Dec 2025 09:45:41 +0800 Li Wang <liwang(a)redhat.com> wrote: > On Mon, Dec 22, 2025 at 6:11 AM David Laight <david.laight.linux(a)gmail.com> > wrote: > > > On Sun, 21 Dec 2025 20:26:37 +0800 > > Li Wang <liwang(a)redhat.com> wrote: > > > > > write_to_hugetlbfs currently parses the -s size argument with atoi() > > > into an int. This silently accepts malformed input, cannot report > > overflow, > > > and can truncate large sizes. > > > > And sscanf() will just ignore invalid trailing characters. > > Probably much the same as atoi() apart from a leading '-'. > > > > Maybe you could use "%zu%c" and check the count is 1 - but I bet > > some static checker won't like that. > > > > Yes, that would be stronger, since it would reject trailing garbage. > But for a selftest this is probably sufficient: switching to size_t and > parsing with "%zu" already avoids the int truncation issue. Have you checked at what does sscanf() does with an overlong digit string? I'd guess that it just processes all the digits and then masks the result to fix (like the kernel one does). It reality scanf() is 'not the function you are lookign for'. IIRC the 'SUS' (used to) say that this was absolutely fine for command line parsing for 'standard utilities'. It is best to use strtoul() and check the 'end' character is '\0'. David > > @Andrew Morton <akpm(a)linux-foundation.org>, > > Hi Andrew, I noticed you have addedthe patches to your mm-new branch, > Let me know if you prefer the "%zu%c" enhancement in a new version. > >

3 weeks

3
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[RFC bpf PATCH 0/2] bpf: Fix memory access tags in helper prototypes

by Zesen Liu

Hi, This series adds missing memory access tags (MEM_RDONLY or MEM_WRITE) to several bpf helper function prototypes that use ARG_PTR_TO_MEM but lack the correct type annotation. Missing memory access tags in helper prototypes can lead to critical correctness issues when the verifier tries to perform code optimization. After commit 37cce22dbd51 ("bpf: verifier: Refactor helper access type tracking"), the verifier relies on the memory access tags, rather than treating all arguments in helper functions as potentially modifying the pointed-to memory. We have already seen several reports regarding this: - commit ac44dcc788b9 ("bpf: Fix verifier assumptions of bpf_d_path's output buffer") adds MEM_WRITE to bpf_d_path; - commit 2eb7648558a7 ("bpf: Specify access type of bpf_sysctl_get_name args") adds MEM_WRITE to bpf_sysctl_get_name. This series looks through all prototypes in the kernel and completes the tags. In addition, this series also adds selftests for some of these functions. I marked the series as RFC since the introduced selftests are fragile and ad hoc (similar to the previously added selftests). The original goal of these tests is to reproduce the case where the verifier wrongly optimizes reads after the helper function is called. However, triggering the error often requires carefully designed code patterns. For example, I had to explicitly use "if (xx != 0)" in my attached tests, because using memcmp will not reproduce the issue. This makes the reproduction heavily dependent on the verifier's internal optimization logic and clutters the selftests with specific, unnatural patterns. Some cases are also hard to trigger by selftests. For example, I couldn't find a triggering pattern for bpf_read_branch_records, since the execution of program seems to be messed up by wrong tags. For bpf_skb_fib_lookup, I also failed to reproduce it because the argument needs content on entry, but the verifier seems to only enable this optimization for fully empty buffers. Since adding selftests does not help with existing issues or prevent future occurrences of similar problems, I believe one way to resolve it is to statically restrict ARG_PTR_TO_MEM from appearing without memory access tags. Using ARG_PTR_TO_MEM alone without tags is nonsensical because: - If the helper does not change the argument, missing MEM_RDONLY causes the verifier to incorrectly reject a read-only buffer. - If the helper does change the argument, missing MEM_WRITE causes the verifier to incorrectly assume the memory is unchanged, leading to potential errors. I am still wondering, if we agree on the above, how should we enforce this restriction? Should we let ARG_PTR_TO_MEM imply MEM_WRITE semantics by default, and change ARG_PTR_TO_MEM | MEM_RDONLY to ARG_CONST_PTR_TO_MEM? Or should we add a check in the verifier to ensure ARG_PTR_TO_MEM always comes with an access tag (though this seems to only catch errors at runtime/testing)? Any insights and comments are welcome. If the individual fix patches for the prototypes look correct, I would also really appreciate it if they could be merged ahead of the discussion. Thanks, Zesen Liu Signed-off-by: Zesen Liu <ftyghome(a)gmail.com> --- Zesen Liu (2): bpf: Fix memory access tags in helper prototypes selftests/bpf: add regression tests for snprintf and get_stack helpers kernel/bpf/helpers.c | 2 +- kernel/trace/bpf_trace.c | 6 +++--- net/core/filter.c | 8 ++++---- tools/testing/selftests/bpf/prog_tests/get_stack_raw_tp.c | 15 +++++++++++++-- tools/testing/selftests/bpf/prog_tests/snprintf.c | 6 ++++++ tools/testing/selftests/bpf/prog_tests/snprintf_btf.c | 3 +++ tools/testing/selftests/bpf/progs/netif_receive_skb.c | 13 ++++++++++++- tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c | 11 ++++++++++- tools/testing/selftests/bpf/progs/test_snprintf.c | 12 ++++++++++++ 9 files changed, 64 insertions(+), 12 deletions(-) --- base-commit: 22cc16c04b7893d8fc22810599f49a305d600b9e change-id: 20251220-helper_proto-fb6e64182467 Best regards, -- Zesen Liu <ftyghome(a)gmail.com>

3 weeks

2
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[PATCH v2 1/5] selftests/mm: fix va_high_addr_switch.sh return value

by Chunyu Hu

Patch series "Fix va_high_addr_switch.sh test failure - again", v2. The series address several issues exist for the va_high_addr_switch test: 1) the test return value is ignored in va_high_addr_switch.sh. 2) the va_high_addr_switch test requires 6 hugepages not 5. 3) the reurn value of the first test in va_high_addr_switch.c can be overridden by the second test. 4) the nr_hugepages setup in run_vmtests.sh for arm64 can be done in va_high_addr_switch.sh too. 5) update a comment for check_test_requirements. Changes in v2: - shorten the comment in for hugepages setup in v1 - add a new patch to fix the return value overridden issue in va_high_addr_switch.c - fix a code comment for check_test_requirements. - update the series summary in patch 1 - add reviewed-by from Luiz Capitulino on patch 1 and patch 3 This patch: (of 5) The return value should be return value of va_high_addr_switch, otherwise a test failure would be silently ignored. Reviewed-by: Luiz Capitulino <luizcap(a)redhat.com> Fixes: d9d957bd7b61 ("selftests/mm: alloc hugepages in va_high_addr_switch test") CC: Luiz Capitulino <luizcap(a)redhat.com> Signed-off-by: Chunyu Hu <chuhu(a)redhat.com> --- Chunyu Hu (5): selftests/mm: fix va_high_addr_switch.sh return value selftests/mm: allocate 6 hugepages in va_high_addr_switch.sh selftests/mm: remove arm64 nr_hugepages setup for va_high_addr_switch test selftests/mm: va_high_addr_switch return fail when either test failed selftests/mm: fix comment for check_test_requirements tools/testing/selftests/mm/run_vmtests.sh | 8 -------- tools/testing/selftests/mm/va_high_addr_switch.c | 10 +++++++--- tools/testing/selftests/mm/va_high_addr_switch.sh | 12 +++++++----- 3 files changed, 14 insertions(+), 16 deletions(-) According to the doc below, I don't add the cover letter, not sure if cover letter is preferred, and if that's the case, the doc need an update. https://www.ozlabs.org/~akpm/stuff/tpp.txt --- tools/testing/selftests/mm/va_high_addr_switch.sh | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/mm/va_high_addr_switch.sh b/tools/testing/selftests/mm/va_high_addr_switch.sh index a7d4b02b21dd..f89fe078a8e6 100755 --- a/tools/testing/selftests/mm/va_high_addr_switch.sh +++ b/tools/testing/selftests/mm/va_high_addr_switch.sh @@ -114,4 +114,6 @@ save_nr_hugepages # 4 keep_mapped pages, and one for tmp usage setup_nr_hugepages 5 ./va_high_addr_switch --run-hugetlb +retcode=$? restore_nr_hugepages +exit $retcode -- 2.49.0

3 weeks

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[PATCH] selftests/hid: run vmtest.sh's pytest with verbose output

by Peter Hutterer

This way we see in the log output which tests were run and which ones were skipped instead of just `....sss.ss..`. Signed-off-by: Peter Hutterer <peter.hutterer(a)who-t.net> --- tools/testing/selftests/hid/vmtest.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/hid/vmtest.sh b/tools/testing/selftests/hid/vmtest.sh index ecbd57f775a0..fc21fb495a8a 100755 --- a/tools/testing/selftests/hid/vmtest.sh +++ b/tools/testing/selftests/hid/vmtest.sh @@ -349,7 +349,7 @@ test_vm_pytest() { shift - vm_ssh -- pytest ${SCRIPT_DIR}/tests --color=yes "$@" \ + vm_ssh -- pytest ${SCRIPT_DIR}/tests -v --color=yes "$@" \ 2>&1 | log_guest "${testname}" return ${PIPESTATUS[0]} -- 2.51.1

3 weeks

1
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[PATCH v2] kunit: Enforce task execution in {soft,hard}irq contexts

by David Gow

The kunit_run_irq_test() helper allows a function to be run in hardirq and softirq contexts (in addition to the task context). It does this by running the user-provided function concurrently in the three contexts, until either a timeout has expired or a number of iterations have completed in the normal task context. However, on setups where the initialisation of the hardirq and softirq contexts (or, indeed, the scheduling of those tasks) is significantly slower than the function execution, it's possible for that number of iterations to be exceeded before any runs in irq contexts actually occur. This occurs with the polyval.test_polyval_preparekey_in_irqs test, which runs 20000 iterations of the relatively fast preparekey function, and therefore fails often under many UML, 32-bit arm, m68k and other environments. Instead, ensure that the max_iterations limit counts executions in all three contexts, and requires at least one of each. This will cause the test to continue iterating until at least the irq contexts have been tested, or the 1s wall-clock limit has been exceeded. This causes the test to pass in all of my environments. In so doing, we also update the task counters to atomic ints, to better match both the 'int' max_iterations input, and to ensure they are correctly updated across contexts. Finally, we also fix a few potential assertion messages to be less-specific to the original crypto usecases. Fixes: b41dc83f0790 ("kunit, lib/crypto: Move run_irq_test() to common header") Signed-off-by: David Gow <davidgow(a)google.com> --- Changes since v1: https://lore.kernel.org/all/20251219080850.921416-1-davidgow@google.com/ - Remove a leftover debug line which forced max_iterations to 1. include/kunit/run-in-irq-context.h | 39 ++++++++++++++++++++---------- 1 file changed, 26 insertions(+), 13 deletions(-) diff --git a/include/kunit/run-in-irq-context.h b/include/kunit/run-in-irq-context.h index 108e96433ea4..84694f383e37 100644 --- a/include/kunit/run-in-irq-context.h +++ b/include/kunit/run-in-irq-context.h @@ -20,8 +20,8 @@ struct kunit_irq_test_state { bool task_func_reported_failure; bool hardirq_func_reported_failure; bool softirq_func_reported_failure; - unsigned long hardirq_func_calls; - unsigned long softirq_func_calls; + atomic_t hardirq_func_calls; + atomic_t softirq_func_calls; struct hrtimer timer; struct work_struct bh_work; }; @@ -32,7 +32,7 @@ static enum hrtimer_restart kunit_irq_test_timer_func(struct hrtimer *timer) container_of(timer, typeof(*state), timer); WARN_ON_ONCE(!in_hardirq()); - state->hardirq_func_calls++; + atomic_inc(&state->hardirq_func_calls); if (!state->func(state->test_specific_state)) state->hardirq_func_reported_failure = true; @@ -48,7 +48,7 @@ static void kunit_irq_test_bh_work_func(struct work_struct *work) container_of(work, typeof(*state), bh_work); WARN_ON_ONCE(!in_serving_softirq()); - state->softirq_func_calls++; + atomic_inc(&state->softirq_func_calls); if (!state->func(state->test_specific_state)) state->softirq_func_reported_failure = true; @@ -59,7 +59,10 @@ static void kunit_irq_test_bh_work_func(struct work_struct *work) * hardirq context concurrently, and reports a failure to KUnit if any * invocation of @func in any context returns false. @func is passed * @test_specific_state as its argument. At most 3 invocations of @func will - * run concurrently: one in each of task, softirq, and hardirq context. + * run concurrently: one in each of task, softirq, and hardirq context. @func + * will continue running until either @max_iterations calls have been made (so + * long as at least one each runs in task, softirq, and hardirq contexts), or + * one second has passed. * * The main purpose of this interrupt context testing is to validate fallback * code paths that run in contexts where the normal code path cannot be used, @@ -85,6 +88,8 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), .test_specific_state = test_specific_state, }; unsigned long end_jiffies; + int hardirq_calls, softirq_calls; + bool allctx = false; /* * Set up a hrtimer (the way we access hardirq context) and a work @@ -94,14 +99,22 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); INIT_WORK_ONSTACK(&state.bh_work, kunit_irq_test_bh_work_func); - /* Run for up to max_iterations or 1 second, whichever comes first. */ + /* Run for up to max_iterations (including at least one task, softirq, + * and hardirq), or 1 second, whichever comes first. + */ end_jiffies = jiffies + HZ; hrtimer_start(&state.timer, KUNIT_IRQ_TEST_HRTIMER_INTERVAL, HRTIMER_MODE_REL_HARD); - for (int i = 0; i < max_iterations && !time_after(jiffies, end_jiffies); - i++) { + for (int task_calls = 0, calls = 0; + ((calls < max_iterations) || !allctx) && !time_after(jiffies, end_jiffies); + task_calls++) { if (!func(test_specific_state)) state.task_func_reported_failure = true; + + hardirq_calls = atomic_read(&state.hardirq_func_calls); + softirq_calls = atomic_read(&state.softirq_func_calls); + calls = task_calls + hardirq_calls + softirq_calls; + allctx = (task_calls > 0) && (hardirq_calls > 0) && (softirq_calls > 0); } /* Cancel the timer and work. */ @@ -109,21 +122,21 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), flush_work(&state.bh_work); /* Sanity check: the timer and BH functions should have been run. */ - KUNIT_EXPECT_GT_MSG(test, state.hardirq_func_calls, 0, + KUNIT_EXPECT_GT_MSG(test, atomic_read(&state.hardirq_func_calls), 0, "Timer function was not called"); - KUNIT_EXPECT_GT_MSG(test, state.softirq_func_calls, 0, + KUNIT_EXPECT_GT_MSG(test, atomic_read(&state.softirq_func_calls), 0, "BH work function was not called"); /* Check for incorrect hash values reported from any context. */ KUNIT_EXPECT_FALSE_MSG( test, state.task_func_reported_failure, - "Incorrect hash values reported from task context"); + "Failure reported from task context"); KUNIT_EXPECT_FALSE_MSG( test, state.hardirq_func_reported_failure, - "Incorrect hash values reported from hardirq context"); + "Failure reported from hardirq context"); KUNIT_EXPECT_FALSE_MSG( test, state.softirq_func_reported_failure, - "Incorrect hash values reported from softirq context"); + "Failure reported from softirq context"); } #endif /* _KUNIT_RUN_IN_IRQ_CONTEXT_H */ -- 2.52.0.322.g1dd061c0dc-goog

3 weeks, 1 day

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[PATCH v2 00/19] rust: replace `kernel::c_str!` with C-Strings

by Tamir Duberstein

This series depends on step 3[0]. Subsystem maintainers: I would appreciate your `Acked-by`s so that this can be taken through Miguel's tree (where the previous series must go). Link: https://lore.kernel.org/all/20250925-cstr-core-v16-0-5cdcb3470ec2@gmail.com/ [0] Signed-off-by: Tamir Duberstein <tamird(a)gmail.com> --- Changes in v2: - Rebase. - Add two patches to address new code. - Drop incorrectly applied Acked-by tags from Danilo. - Link to v1: https://lore.kernel.org/r/20250710-core-cstr-cstrings-v1-0-027420ea799e@gma… --- Tamir Duberstein (19): drivers: net: replace `kernel::c_str!` with C-Strings gpu: nova-core: replace `kernel::c_str!` with C-Strings rust: auxiliary: replace `kernel::c_str!` with C-Strings rust: clk: replace `kernel::c_str!` with C-Strings rust: configfs: replace `kernel::c_str!` with C-Strings rust: cpufreq: replace `kernel::c_str!` with C-Strings rust: device: replace `kernel::c_str!` with C-Strings rust: firmware: replace `kernel::c_str!` with C-Strings rust: kunit: replace `kernel::c_str!` with C-Strings rust: macros: replace `kernel::c_str!` with C-Strings rust: miscdevice: replace `kernel::c_str!` with C-Strings rust: net: replace `kernel::c_str!` with C-Strings rust: pci: replace `kernel::c_str!` with C-Strings rust: platform: replace `kernel::c_str!` with C-Strings rust: seq_file: replace `kernel::c_str!` with C-Strings rust: str: replace `kernel::c_str!` with C-Strings rust: sync: replace `kernel::c_str!` with C-Strings rust: io: replace `kernel::c_str!` with C-Strings rust: regulator: replace `kernel::c_str!` with C-Strings drivers/block/rnull.rs | 2 +- drivers/cpufreq/rcpufreq_dt.rs | 5 ++--- drivers/gpu/drm/nova/driver.rs | 10 +++++----- drivers/gpu/nova-core/driver.rs | 6 +++--- drivers/net/phy/ax88796b_rust.rs | 7 +++---- drivers/net/phy/qt2025.rs | 5 ++--- rust/kernel/clk.rs | 6 ++---- rust/kernel/configfs.rs | 9 +++++---- rust/kernel/cpufreq.rs | 3 +-- rust/kernel/device.rs | 4 +--- rust/kernel/device/property.rs | 6 +++--- rust/kernel/firmware.rs | 6 +++--- rust/kernel/io/mem.rs | 7 +++---- rust/kernel/kunit.rs | 11 ++++------- rust/kernel/net/phy.rs | 6 ++---- rust/kernel/platform.rs | 6 +++--- rust/kernel/regulator.rs | 9 +++------ rust/kernel/seq_file.rs | 4 ++-- rust/kernel/str.rs | 5 ++--- rust/kernel/sync.rs | 5 ++--- rust/kernel/sync/completion.rs | 2 +- rust/kernel/workqueue.rs | 8 ++++---- rust/macros/kunit.rs | 10 +++++----- rust/macros/module.rs | 2 +- samples/rust/rust_configfs.rs | 5 ++--- samples/rust/rust_driver_auxiliary.rs | 4 ++-- samples/rust/rust_driver_faux.rs | 4 ++-- samples/rust/rust_driver_pci.rs | 4 ++-- samples/rust/rust_driver_platform.rs | 30 ++++++++++++++---------------- samples/rust/rust_misc_device.rs | 3 +-- scripts/rustdoc_test_gen.rs | 4 ++-- 31 files changed, 88 insertions(+), 110 deletions(-) --- base-commit: f3f6b3664302e16ef1c6b91034a72df5564d6b8a change-id: 20250710-core-cstr-cstrings-1faaa632f0fd prerequisite-change-id: 20250201-cstr-core-d4b9b69120cf:v16 prerequisite-patch-id: e0ca756f740ab0ce7478bbf6510948ba89529a2f prerequisite-patch-id: 6d8dbdf864f79fc0c2820e702a7cb87753649ca0 prerequisite-patch-id: 7d4d1d036043a85dcbaf0d09ea85768120efe094 Best regards, -- Tamir Duberstein <tamird(a)gmail.com>

3 weeks, 1 day

8
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[PATCH v3 0/3] selftests/mm: hugetlb cgroup charging: robustness fixes

by Li Wang

Changes in v3: - 1/3: no changes. - 2/3: reorder with 3/3, and drop the 'size=' mount args. - 3/3: add $path check, improve varible declaration, sleep 1s for 60 tryies. Changes in v2: - 1/3: Parse -s using sscanf("%zu", ...) instead of strtoull(). - 2/3: Fix typo in charge_reserved_hugetlb.sh ("reseravation" -> "reservation"). - 3/3: No changes. This series fixes a few issues in the hugetlb cgroup charging selftests (write_to_hugetlbfs.c + charge_reserved_hugetlb.sh) that show up on systems with large hugepages (e.g. 512MB) and when failures cause the test to wait indefinitely. On an aarch64 64k page kernel with 512MB hugepages, the test consistently fails in write_to_hugetlbfs with ENOMEM and then hangs waiting for the expected usage values. The root cause is that charge_reserved_hugetlb.sh mounts hugetlbfs with a fixed size=256M, which is smaller than a single hugepage, resulting in a mount with size=0 capacity. In addition, write_to_hugetlbfs previously parsed -s via atoi() into an int, which can overflow and print negative sizes. Reproducer / environment: - Kernel: 6.12.0-xxx.el10.aarch64+64k - Hugepagesize: 524288 kB (512MB) - ./charge_reserved_hugetlb.sh -cgroup-v2 - Observed mount: pagesize=512M,size=0 before this series After applying the series, the test completes successfully on the above setup. Li Wang (3): selftests/mm/write_to_hugetlbfs: parse -s as size_t selftests/mm/charge_reserved_hugetlb: drop mount size for hugetlbfs selftests/mm/charge_reserved_hugetlb.sh: add waits with timeout helper .../selftests/mm/charge_reserved_hugetlb.sh | 55 +++++++++++-------- .../testing/selftests/mm/write_to_hugetlbfs.c | 9 ++- 2 files changed, 38 insertions(+), 26 deletions(-) -- 2.49.0

3 weeks, 1 day

5
11
0 0

[PATCH] KVM: selftests: Fix sign extension bug in get_desc64_base()

by MJ Pooladkhay

The function get_desc64_base() performs a series of bitwise left shifts on fields of various sizes. More specifically, when performing '<< 24' on 'desc->base2' (which is a u8), 'base2' is promoted to a signed integer before shifting. In a scenario where base2 >= 0x80, the shift places a 1 into bit 31, causing the 32-bit intermediate value to become negative. When this result is cast to uint64_t or ORed into the return value, sign extension occurs, corrupting the upper 32 bits of the address (base3). Example: Given: base0 = 0x5000 base1 = 0xd6 base2 = 0xf8 base3 = 0xfffffe7c Expected return: 0xfffffe7cf8d65000 Actual return: 0xfffffffff8d65000 Fix this by explicitly casting the fields to 'uint64_t' before shifting to prevent sign extension. Signed-off-by: MJ Pooladkhay <mj(a)pooladkhay.com> --- While using get_desc64_base() to set the HOST_TR_BASE value for a custom educational hypervisor, I observed system freezes, either immediately or after migrating the guest to a new core. I eventually realized that KVM uses get_cpu_entry_area() for the TR base. Switching to that fixed my freezes (which were triple faults on one core followed by soft lockups on others, waiting on smp_call_function_many_cond) and helped me identify the sign-extension bug in this helper function that was corrupting the HOST_TR_BASE value. Thanks, MJ Pooladkhay tools/testing/selftests/kvm/include/x86/processor.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/include/x86/processor.h b/tools/testing/selftests/kvm/include/x86/processor.h index 57d62a425..cc2f8fb6f 100644 --- a/tools/testing/selftests/kvm/include/x86/processor.h +++ b/tools/testing/selftests/kvm/include/x86/processor.h @@ -436,8 +436,11 @@ struct kvm_x86_state { static inline uint64_t get_desc64_base(const struct desc64 *desc) { - return ((uint64_t)desc->base3 << 32) | - (desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24)); + uint64_t low = (uint64_t)desc->base0 | + ((uint64_t)desc->base1 << 16) | + ((uint64_t)desc->base2 << 24); + + return (uint64_t)desc->base3 << 32 | low; } static inline uint64_t rdtsc(void) -- 2.52.0

3 weeks, 1 day

2
2
0 0

[PATCH v3 00/14] tools/nolibc: always use 64-bit time-related types

by Thomas Weißschuh

nolibc currently uses 32-bit types for various APIs. These are problematic as their reduced value range can lead to truncated values. Intended for 6.19. Signed-off-by: Thomas Weißschuh <linux(a)weissschuh.net> --- Changes in v3: - Only use _Static_assert() where available - Link to v2: https://lore.kernel.org/r/20251122-nolibc-uapi-types-v2-0-b814a43654f5@weis… Changes in v2: - Drop already applied ino_t and off_t patches. - Also handle 'struct timeval'. - Make the progression of the series a bit clearer. - Add compatibility assertions. - Link to v1: https://lore.kernel.org/r/20251029-nolibc-uapi-types-v1-0-e79de3b215d8@weis… --- Thomas Weißschuh (14): tools/nolibc/poll: use kernel types for system call invocations tools/nolibc/poll: drop __NR_poll fallback tools/nolibc/select: drop non-pselect based implementations tools/nolibc/time: drop invocation of gettimeofday system call tools/nolibc: prefer explicit 64-bit time-related system calls tools/nolibc/gettimeofday: avoid libgcc 64-bit divisions tools/nolibc/select: avoid libgcc 64-bit multiplications tools/nolibc: use custom structs timespec and timeval tools/nolibc: always use 64-bit time types selftests/nolibc: test compatibility of nolibc and kernel time types tools/nolibc: remove time conversions tools/nolibc: add compiler version detection macros tools/nolibc: add __nolibc_static_assert() selftests/nolibc: add static assertions around time types handling tools/include/nolibc/arch-s390.h | 3 + tools/include/nolibc/compiler.h | 24 +++++++ tools/include/nolibc/poll.h | 14 ++-- tools/include/nolibc/std.h | 2 +- tools/include/nolibc/sys/select.h | 25 ++----- tools/include/nolibc/sys/time.h | 6 +- tools/include/nolibc/sys/timerfd.h | 32 +++------ tools/include/nolibc/time.h | 102 +++++++++------------------ tools/include/nolibc/types.h | 17 ++++- tools/testing/selftests/nolibc/nolibc-test.c | 27 +++++++ 10 files changed, 129 insertions(+), 123 deletions(-) --- base-commit: 351ec197a66e47bea17c3d803c5472473640dd0d change-id: 20251001-nolibc-uapi-types-1c072d10fcc7 Best regards, -- Thomas Weißschuh <linux(a)weissschuh.net>

3 weeks, 1 day

3
18
0 0

[PATCH] selftests: net: fib-onlink-tests: Set high metric for default IPv6 route

by Ricardo B. Marlière

Currently, the test breaks if the SUT already has a default route configured for IPv6. Fix by adding "metric 9999" to the `ip -6 ro add` command, so that multiple default routes can coexist. Fixes: 4ed591c8ab44 ("net/ipv6: Allow onlink routes to have a device mismatch if it is the default route") Signed-off-by: Ricardo B. Marlière <rbm(a)suse.com> --- tools/testing/selftests/net/fib-onlink-tests.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/fib-onlink-tests.sh b/tools/testing/selftests/net/fib-onlink-tests.sh index ec2d6ceb1f08..acf6b0617373 100755 --- a/tools/testing/selftests/net/fib-onlink-tests.sh +++ b/tools/testing/selftests/net/fib-onlink-tests.sh @@ -207,7 +207,7 @@ setup() ip -netns ${PEER_NS} addr add ${V6ADDRS[p${n}]}/64 dev ${NETIFS[p${n}]} nodad done - ip -6 ro add default via ${V6ADDRS[p3]/::[0-9]/::64} + ip -6 ro add default via ${V6ADDRS[p3]/::[0-9]/::64} metric 9999 ip -6 ro add table ${VRF_TABLE} default via ${V6ADDRS[p7]/::[0-9]/::64} set +e --- base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 change-id: 20251218-rbm-selftests-net-fib-onlink-873ad01e6884 Best regards, -- Ricardo B. Marlière <rbm(a)suse.com>

3 weeks, 2 days

3
4
0 0

[PATCH v2 0/3] selftests/mm: hugetlb cgroup charging: robustness fixes

by Li Wang

Changes in v2: - 1/3: Parse -s using sscanf("%zu", ...) instead of strtoull(). - 2/3: Fix typo in charge_reserved_hugetlb.sh ("reseravation" -> "reservation"). - 3/3: No changes. This series fixes a few issues in the hugetlb cgroup charging selftests (write_to_hugetlbfs.c + charge_reserved_hugetlb.sh) that show up on systems with large hugepages (e.g. 512MB) and when failures cause the test to wait indefinitely. On an aarch64 64k page kernel with 512MB hugepages, the test consistently fails in write_to_hugetlbfs with ENOMEM and then hangs waiting for the expected usage values. The root cause is that charge_reserved_hugetlb.sh mounts hugetlbfs with a fixed size=256M, which is smaller than a single hugepage, resulting in a mount with size=0 capacity. In addition, write_to_hugetlbfs previously parsed -s via atoi() into an int, which can overflow and print negative sizes. Reproducer / environment: - Kernel: 6.12.0-xxx.el10.aarch64+64k - Hugepagesize: 524288 kB (512MB) - ./charge_reserved_hugetlb.sh -cgroup-v2 - Observed mount: pagesize=512M,size=0 before this series After applying the series, the test completes successfully on the above setup. Li Wang (3): selftests/mm/write_to_hugetlbfs: parse -s as size_t selftests/mm/charge_reserved_hugetlb.sh: add waits with timeout helper selftests/mm/charge_reserved_hugetlb: fix hugetlbfs mount size for large hugepages .../selftests/mm/charge_reserved_hugetlb.sh | 51 ++++++++++--------- .../testing/selftests/mm/write_to_hugetlbfs.c | 9 ++-- 2 files changed, 34 insertions(+), 26 deletions(-) -- 2.49.0

3 weeks, 2 days

2
12
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[PATCH v1 1/3] selftests/mm: fix va_high_addr_switch.sh return value

by Chunyu Hu

Patch series "Fix va_high_addr_switch.sh test failure - again", v1. There are two issues exist for the va_high_addr_switch test. One issue is the test return value is ignored in va_high_addr_switch.sh. The second is the va_high_addr_switch requires 6 hugepages but it requires 5. Besides that, the nr_hugepages setup in run_vmtests.sh for arm64 can be done in va_high_addr_switch.sh too. This patch: (of 3) The return value should be return value of va_high_addr_switch, otherwise a test failure would be silently ignored. Fixes: d9d957bd7b61 ("selftests/mm: alloc hugepages in va_high_addr_switch test") CC: Luiz Capitulino <luizcap(a)redhat.com> Signed-off-by: Chunyu Hu <chuhu(a)redhat.com> --- tools/testing/selftests/mm/va_high_addr_switch.sh | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/mm/va_high_addr_switch.sh b/tools/testing/selftests/mm/va_high_addr_switch.sh index a7d4b02b21dd..f89fe078a8e6 100755 --- a/tools/testing/selftests/mm/va_high_addr_switch.sh +++ b/tools/testing/selftests/mm/va_high_addr_switch.sh @@ -114,4 +114,6 @@ save_nr_hugepages # 4 keep_mapped pages, and one for tmp usage setup_nr_hugepages 5 ./va_high_addr_switch --run-hugetlb +retcode=$? restore_nr_hugepages +exit $retcode -- 2.49.0

3 weeks, 2 days

2
7
0 0

[GIT PULL] kunit fixes update for Linux 6.19-rc3

by Shuah Khan

Hi Linus, Please pull the following fixes update for Linux 6.19-rc3. Drops unused parameter from kunit_device_register_internal and makes FAULT_TEST default to n when PANIC_ON_OOPS. Note: Sending this early for 6.19-rc3 (way too late for rc2 anyways) diff is attached. thanks, -- Shuah ---------------------------------------------------------------- The following changes since commit 8f0b4cce4481fb22653697cced8d0d04027cb1e8: Linux 6.19-rc1 (2025-12-14 16:05:07 +1200) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest tags/linux_kselftest-kunit-fixes-6.19-rc3 for you to fetch changes up to c33b68801fbe9d5ee8a9178beb5747ec65873530: kunit: make FAULT_TEST default to n when PANIC_ON_OOPS (2025-12-15 09:27:19 -0700) ---------------------------------------------------------------- linux_kselftest-kunit-fixes-6.19-rc3 Drops unused parameter from kunit_device_register_internal and makes FAULT_TEST default to n when PANIC_ON_OOPS. ---------------------------------------------------------------- Brendan Jackman (1): kunit: make FAULT_TEST default to n when PANIC_ON_OOPS Uwe Kleine-König (1): kunit: Drop unused parameter from kunit_device_register_internal lib/kunit/Kconfig | 2 +- lib/kunit/device.c | 7 +++---- 2 files changed, 4 insertions(+), 5 deletions(-) ----------------------------------------------------------------

3 weeks, 3 days

2
1
0 0

[PATCH 0/3] selftests/mm: hugetlb cgroup charging: robustness fixes

by Li Wang

This series fixes a few issues in the hugetlb cgroup charging selftests (write_to_hugetlbfs.c + charge_reserved_hugetlb.sh) that show up on systems with large hugepages (e.g. 512MB) and when failures cause the test to wait indefinitely. On an aarch64 64k page kernel with 512MB hugepages, the test consistently fails in write_to_hugetlbfs with ENOMEM and then hangs waiting for the expected usage values. The root cause is that charge_reserved_hugetlb.sh mounts hugetlbfs with a fixed size=256M, which is smaller than a single hugepage, resulting in a mount with size=0 capacity. In addition, write_to_hugetlbfs previously parsed -s via atoi() into an int, which can overflow and print negative sizes. Reproducer / environment: - Kernel: 6.12.0-xxx.el10.aarch64+64k - Hugepagesize: 524288 kB (512MB) - ./charge_reserved_hugetlb.sh -cgroup-v2 - Observed mount: pagesize=512M,size=0 before this series After applying the series, the test completes successfully on the above setup. Li Wang (3): selftests/mm/write_to_hugetlbfs: parse -s with strtoull and use size_t selftests/mm/charge_reserved_hugetlb.sh: add waits with timeout helper selftests/mm/charge_reserved_hugetlb: fix hugetlbfs mount size for large hugepages .../selftests/mm/charge_reserved_hugetlb.sh | 49 ++++++++++--------- .../testing/selftests/mm/write_to_hugetlbfs.c | 19 +++++-- 2 files changed, 43 insertions(+), 25 deletions(-) -- 2.49.0

3 weeks, 3 days

2
4
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[PATCH v9 00/16] arm64: entry: Convert to Generic Entry

by Jinjie Ruan

Currently, x86, Riscv, Loongarch use the Generic Entry which makes maintainers' work easier and codes more elegant. arm64 has already successfully switched to the Generic IRQ Entry in commit b3cf07851b6c ("arm64: entry: Switch to generic IRQ entry"), it is time to completely convert arm64 to Generic Entry. The goal is to bring arm64 in line with other architectures that already use the generic entry infrastructure, reducing duplicated code and making it easier to share future changes in entry/exit paths, such as "Syscall User Dispatch". This patch set is rebased on v6.18-rc7. And the performance was measured on Kunpeng 920 using "perf bench basic syscall" with "arm64.nopauth selinux=0 audit=1". After switch to Generic Entry, the performance are below: | Metric | W/O Generic Framework | With Generic Framework | Change | | ---------- | --------------------- | ---------------------- | ------ | | Total time | 2.130 [sec] | 2.235 [sec] | ↑4.90% | | usecs/op | 0.213095 | 0.223512 | ↑4.89% | | ops/sec | 4,692,753 | 4,474,044 | ↓4.89% | Compared to earlier with arch specific handling, the performance decreased by approximately 4.9%. On the basis of optimizing syscall_get_arguments()[1], el0_svc_common() and syscall_exit_work(), the performance are below: | Metric | W/O Generic Entry | With Generic Entry opt| Change | | ---------- | ----------------- | ------------------ | ------ | | Total time | 2.130 [sec] | 2.134 [sec] | ↑0.18% | | usecs/op | 0.213095 | 0.213414 | ↑0.15% | | ops/sec | 4,692,753 | 4,685,737 | ↓0.15% | Therefore, after the optimization, ARM64 System Call performance remains almost unchanged. It was tested ok with following test cases on kunpeng920 and QEMU virt platform: - Perf tests. - Different `dynamic preempt` mode switch. - Pseudo NMI tests. - Stress-ng CPU stress test. - Hackbench stress test. - MTE test case in Documentation/arch/arm64/memory-tagging-extension.rst and all test cases in tools/testing/selftests/arm64/mte/*. - "sud" selftest testcase. - get_set_sud, get_syscall_info, set_syscall_info, peeksiginfo in tools/testing/selftests/ptrace. - breakpoint_test_arm64 in selftests/breakpoints. - syscall-abi and ptrace in tools/testing/selftests/arm64/abi - fp-ptrace, sve-ptrace, za-ptrace in selftests/arm64/fp. - vdso_test_getrandom in tools/testing/selftests/vDSO - Strace tests. The test QEMU configuration is as follows: qemu-system-aarch64 \ -M virt,gic-version=3,virtualization=on,mte=on \ -cpu max,pauth-impdef=on \ -kernel Image \ -smp 8,sockets=1,cores=4,threads=2 \ -m 512m \ -nographic \ -no-reboot \ -device virtio-rng-pci \ -append "root=/dev/vda rw console=ttyAMA0 kgdboc=ttyAMA0,115200 \ earlycon preempt=voluntary irqchip.gicv3_pseudo_nmi=1" \ -drive if=none,file=images/rootfs.ext4,format=raw,id=hd0 \ -device virtio-blk-device,drive=hd0 \ [1]: https://lore.kernel.org/all/20251201120633.1193122-3-ruanjinjie@huawei.com/ Changes in v9: - Move "Return early for ptrace_report_syscall_entry() error" patch ahead to make it not introduce a regression. - Not check _TIF_SECCOMP/SYSCALL_EMU for syscall_exit_work() in a separate patch. - Do not report_syscall_exit() for PTRACE_SYSEMU_SINGLESTEP in a separate patch. - Add two performance patch to improve the arm64 performance. - Add Reviewed-by. - Link to v8: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ Changes in v8: - Rename "report_syscall_enter()" to "report_syscall_entry()". - Add ptrace_save_reg() to avoid duplication. - Remove unused _TIF_WORK_MASK in a standalone patch. - Align syscall_trace_enter() return value with the generic version. - Use "scno" instead of regs->syscallno in el0_svc_common(). - Move rseq_syscall() ahead in a standalone patch to clarify it clearly. - Rename "syscall_trace_exit()" to "syscall_exit_work()". - Keep the goto in el0_svc_common(). - No argument was passed to __secure_computing() and check -1 not -1L. - Remove "Add has_syscall_work() helper" patch. - Move "Add syscall_exit_to_user_mode_prepare() helper" patch later. - Add miss header for asm/entry-common.h. - Update the implementation of arch_syscall_is_vdso_sigreturn(). - Add "ARCH_SYSCALL_WORK_EXIT" to be defined as "SECCOMP | SYSCALL_EMU" to keep the behaviour unchanged. - Add more testcases test. - Add Reviewed-by. - Update the commit message. - Link to v7: https://lore.kernel.org/all/20251117133048.53182-1-ruanjinjie@huawei.com/ Chanegs in v7: - Support "Syscall User Dispatch" by implementing arch_syscall_is_vdso_sigreturn() as kemal suggested. - Add aarch64 support for "sud" selftest testcase, which tested ok with the patch series. - Fix the kernel test robot warning for arch_ptrace_report_syscall_entry() and arch_ptrace_report_syscall_exit() in asm/entry-common.h. - Add perf syscall performance test. - Link to v6: https://lore.kernel.org/all/20250916082611.2972008-1-ruanjinjie@huawei.com/ Changes in v6: - Rebased on v6.17-rc5-next as arm64 generic irq entry has merged. - Update the commit message. - Link to v5: https://lore.kernel.org/all/20241206101744.4161990-1-ruanjinjie@huawei.com/ Changes in v5: - Not change arm32 and keep inerrupts_enabled() macro for gicv3 driver. - Move irqentry_state definition into arch/arm64/kernel/entry-common.c. - Avoid removing the __enter_from_*() and __exit_to_*() wrappers. - Update "irqentry_state_t ret/irq_state" to "state" to keep it consistently. - Use generic irq entry header for PREEMPT_DYNAMIC after split the generic entry. - Also refactor the ARM64 syscall code. - Introduce arch_ptrace_report_syscall_entry/exit(), instead of arch_pre/post_report_syscall_entry/exit() to simplify code. - Make the syscall patches clear separation. - Update the commit message. - Link to v4: https://lore.kernel.org/all/20241025100700.3714552-1-ruanjinjie@huawei.com/ Changes in v4: - Rework/cleanup split into a few patches as Mark suggested. - Replace interrupts_enabled() macro with regs_irqs_disabled(), instead of left it here. - Remove rcu and lockdep state in pt_regs by using temporary irqentry_state_t as Mark suggested. - Remove some unnecessary intermediate functions to make it clear. - Rework preempt irq and PREEMPT_DYNAMIC code to make the switch more clear. - arch_prepare_*_entry/exit() -> arch_pre_*_entry/exit(). - Expand the arch functions comment. - Make arch functions closer to its caller. - Declare saved_reg in for block. - Remove arch_exit_to_kernel_mode_prepare(), arch_enter_from_kernel_mode(). - Adjust "Add few arch functions to use generic entry" patch to be the penultimate. - Update the commit message. - Add suggested-by. - Link to v3: https://lore.kernel.org/all/20240629085601.470241-1-ruanjinjie@huawei.com/ Changes in v3: - Test the MTE test cases. - Handle forget_syscall() in arch_post_report_syscall_entry() - Make the arch funcs not use __weak as Thomas suggested, so move the arch funcs to entry-common.h, and make arch_forget_syscall() folded in arch_post_report_syscall_entry() as suggested. - Move report_single_step() to thread_info.h for arm64 - Change __always_inline() to inline, add inline for the other arch funcs. - Remove unused signal.h for entry-common.h. - Add Suggested-by. - Update the commit message. Changes in v2: - Add tested-by. - Fix a bug that not call arch_post_report_syscall_entry() in syscall_trace_enter() if ptrace_report_syscall_entry() return not zero. - Refactor report_syscall(). - Add comment for arch_prepare_report_syscall_exit(). - Adjust entry-common.h header file inclusion to alphabetical order. - Update the commit message. Jinjie Ruan (15): arm64: Remove unused _TIF_WORK_MASK arm64/ptrace: Split report_syscall() arm64/ptrace: Return early for ptrace_report_syscall_entry() error arm64/ptrace: Refactor syscall_trace_enter/exit() arm64: ptrace: Move rseq_syscall() before audit_syscall_exit() arm64: syscall: Rework el0_svc_common() arm64/ptrace: Not check _TIF_SECCOMP/SYSCALL_EMU for syscall_exit_work() arm64/ptrace: Do not report_syscall_exit() for PTRACE_SYSEMU_SINGLESTEP arm64/ptrace: Expand secure_computing() in place arm64/ptrace: Use syscall_get_arguments() helper entry: Split syscall_exit_to_user_mode_work() for arch reuse entry: Add arch_ptrace_report_syscall_entry/exit() arm64: entry: Convert to generic entry arm64: Inline el0_svc_common() entry: Inline syscall_exit_work() kemal (1): selftests: sud_test: Support aarch64 arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/entry-common.h | 76 ++++++++++++++ arch/arm64/include/asm/syscall.h | 19 +++- arch/arm64/include/asm/thread_info.h | 22 +---- arch/arm64/kernel/debug-monitors.c | 7 ++ arch/arm64/kernel/ptrace.c | 94 ------------------ arch/arm64/kernel/signal.c | 2 +- arch/arm64/kernel/syscall.c | 29 ++---- include/linux/entry-common.h | 98 ++++++++++++++++--- kernel/entry/syscall-common.c | 60 +++++------- .../syscall_user_dispatch/sud_test.c | 4 + 11 files changed, 220 insertions(+), 193 deletions(-) -- 2.34.1

3 weeks, 3 days

5
35
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[PATCH] kunit: Protect KUNIT_BINARY_STR_ASSERTION against ERR_PTR values

by Richard Fitzgerald

Replace the NULL checks with IS_ERR_OR_NULL() in KUNIT_BINARY_STR_ASSERTION() to prevent the strcmp() faulting if a passed pointer is an ERR_PTR. Commit 7ece381aa72d4 ("kunit: Protect string comparisons against NULL") added the checks for NULL on both pointers so that asserts would fail, instead of faulting, if either pointer is NULL. But either pointer could hold an ERR_PTR value. This assumes that the assertion is expecting both strings to be valid, and is asserting the equality of their _content_. Signed-off-by: Richard Fitzgerald <rf(a)opensource.cirrus.com> --- include/kunit/test.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/kunit/test.h b/include/kunit/test.h index 5ec5182b5e57..9cd1594ab697 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -906,7 +906,8 @@ do { \ }; \ \ _KUNIT_SAVE_LOC(test); \ - if (likely((__left) && (__right) && (strcmp(__left, __right) op 0))) \ + if (likely(!IS_ERR_OR_NULL(__left) && !IS_ERR_OR_NULL(__right) && \ + (strcmp(__left, __right) op 0))) \ break; \ \ \ -- 2.47.3

3 weeks, 3 days

2
1
0 0

[PATCH net-next v9 0/6] Suspend IRQs during application busy periods

by Joe Damato

Greetings: Welcome to v9, see changelog below. This revision addresses feedback Willem gave on the selftests. No functional or code changes to the implementation were made and performance tests were not re-run. This series introduces a new mechanism, IRQ suspension, which allows network applications using epoll to mask IRQs during periods of high traffic while also reducing tail latency (compared to existing mechanisms, see below) during periods of low traffic. In doing so, this balances CPU consumption with network processing efficiency. Martin Karsten (CC'd) and I have been collaborating on this series for several months and have appreciated the feedback from the community on our RFC [1]. We've updated the cover letter and kernel documentation in an attempt to more clearly explain how this mechanism works, how applications can use it, and how it compares to existing mechanisms in the kernel. I briefly mentioned this idea at netdev conf 2024 (for those who were there) and Martin described this idea in an earlier paper presented at Sigmetrics 2024 [2]. ~ The short explanation (TL;DR) We propose adding a new napi config parameter: irq_suspend_timeout to help balance CPU usage and network processing efficiency when using IRQ deferral and napi busy poll. If this parameter is set to a non-zero value *and* a user application has enabled preferred busy poll on a busy poll context (via the EPIOCSPARAMS ioctl introduced in commit 18e2bf0edf4d ("eventpoll: Add epoll ioctl for epoll_params")), then application calls to epoll_wait for that context will cause device IRQs and softirq processing to be suspended as long as epoll_wait successfully retrieves data from the NAPI. Each time data is retrieved, the irq_suspend_timeout is deferred. If/when network traffic subsides and epoll_wait returns no data, IRQ suspension is immediately reverted back to the existing napi_defer_hard_irqs and gro_flush_timeout mechanism which was introduced in commit 6f8b12d661d0 ("net: napi: add hard irqs deferral feature")). The irq_suspend_timeout serves as a safety mechanism. If userland takes a long time processing data, irq_suspend_timeout will fire and restart normal NAPI processing. For a more in depth explanation, please continue reading. ~ Comparison with existing mechanisms Interrupt mitigation can be accomplished in napi software, by setting napi_defer_hard_irqs and gro_flush_timeout, or via interrupt coalescing in the NIC. This can be quite efficient, but in both cases, a fixed timeout (or packet count) needs to be configured. However, a fixed timeout cannot effectively support both low- and high-load situations: At low load, an application typically processes a few requests and then waits to receive more input data. In this scenario, a large timeout will cause unnecessary latency. At high load, an application typically processes many requests before being ready to receive more input data. In this case, a small timeout will likely fire prematurely and trigger irq/softirq processing, which interferes with the application's execution. This causes overhead, most likely due to cache contention. While NICs attempt to provide adaptive interrupt coalescing schemes, these cannot properly take into account application-level processing. An alternative packet delivery mechanism is busy-polling, which results in perfect alignment of application processing and network polling. It delivers optimal performance (throughput and latency), but results in 100% cpu utilization and is thus inefficient for below-capacity workloads. We propose to add a new packet delivery mode that properly alternates between busy polling and interrupt-based delivery depending on busy and idle periods of the application. During a busy period, the system operates in busy-polling mode, which avoids interference. During an idle period, the system falls back to interrupt deferral, but with a small timeout to avoid excessive latencies. This delivery mode can also be viewed as an extension of basic interrupt deferral, but alternating between a small and a very large timeout. This delivery mode is efficient, because it avoids softirq execution interfering with application processing during busy periods. It can be used with blocking epoll_wait to conserve cpu cycles during idle periods. The effect of alternating between busy and idle periods is that performance (throughput and latency) is very close to full busy polling, while cpu utilization is lower and very close to interrupt mitigation. ~ Usage details IRQ suspension is introduced via a per-NAPI configuration parameter that controls the maximum time that IRQs can be suspended. Here's how it is intended to work: - The user application (or system administrator) uses the netdev-genl netlink interface to set the pre-existing napi_defer_hard_irqs and gro_flush_timeout NAPI config parameters to enable IRQ deferral. - The user application (or system administrator) sets the proposed irq_suspend_timeout parameter via the netdev-genl netlink interface to a larger value than gro_flush_timeout to enable IRQ suspension. - The user application issues the existing epoll ioctl to set the prefer_busy_poll flag on the epoll context. - The user application then calls epoll_wait to busy poll for network events, as it normally would. - If epoll_wait returns events to userland, IRQs are suspended for the duration of irq_suspend_timeout. - If epoll_wait finds no events and the thread is about to go to sleep, IRQ handling using napi_defer_hard_irqs and gro_flush_timeout is resumed. As long as epoll_wait is retrieving events, IRQs (and softirq processing) for the NAPI being polled remain disabled. When network traffic reduces, eventually a busy poll loop in the kernel will retrieve no data. When this occurs, regular IRQ deferral using gro_flush_timeout for the polled NAPI is re-enabled. Unless IRQ suspension is continued by subsequent calls to epoll_wait, it automatically times out after the irq_suspend_timeout timer expires. Regular deferral is also immediately re-enabled when the epoll context is destroyed. ~ Usage scenario The target scenario for IRQ suspension as packet delivery mode is a system that runs a dominant application with substantial network I/O. The target application can be configured to receive input data up to a certain batch size (via epoll_wait maxevents parameter) and this batch size determines the worst-case latency that application requests might experience. Because packet delivery is suspended during the target application's processing, the batch size also determines the worst-case latency of concurrent applications using the same RX queue(s). gro_flush_timeout should be set as small as possible, but large enough to make sure that a single request is likely not being interfered with. irq_suspend_timeout is largely a safety mechanism against misbehaving applications. It should be set large enough to cover the processing of an entire application batch, i.e., the factor between gro_flush_timeout and irq_suspend_timeout should roughly correspond to the maximum batch size that the target application would process in one go. ~ Important call out in the implementation - Enabling per epoll-context preferred busy poll will now effectively lead to a nonblocking iteration through napi_busy_loop, even when busy_poll_usecs is 0. See patch 4. ~ Benchmark configs & descriptions The changes were benchmarked with memcached [3] using the benchmarking tool mutilate [4]. To facilitate benchmarking, a small patch [5] was applied to memcached 1.6.29 to allow setting per-epoll context preferred busy poll and other settings via environment variables. Another small patch [6] was applied to libevent to enable full busy-polling. Multiple scenarios were benchmarked as described below and the scripts used for producing these results can be found on github [7] (note: all scenarios use NAPI-based traffic splitting via SO_INCOMING_ID by passing -N to memcached): - base: - no other options enabled - deferX: - set defer_hard_irqs to 100 - set gro_flush_timeout to X,000 - napibusy: - set defer_hard_irqs to 100 - set gro_flush_timeout to 200,000 - enable busy poll via the existing ioctl (busy_poll_usecs = 64, busy_poll_budget = 64, prefer_busy_poll = true) - fullbusy: - set defer_hard_irqs to 100 - set gro_flush_timeout to 5,000,000 - enable busy poll via the existing ioctl (busy_poll_usecs = 1000, busy_poll_budget = 64, prefer_busy_poll = true) - change memcached's nonblocking epoll_wait invocation (via libevent) to using a 1 ms timeout - suspend0: - set defer_hard_irqs to 0 - set gro_flush_timeout to 0 - set irq_suspend_timeout to 20,000,000 - enable busy poll via the existing ioctl (busy_poll_usecs = 0, busy_poll_budget = 64, prefer_busy_poll = true) - suspendX: - set defer_hard_irqs to 100 - set gro_flush_timeout to X,000 - set irq_suspend_timeout to 20,000,000 - enable busy poll via the existing ioctl (busy_poll_usecs = 0, busy_poll_budget = 64, prefer_busy_poll = true) ~ Benchmark results Tested on: Single socket AMD EPYC 7662 64-Core Processor Hyperthreading disabled 4 NUMA Zones (NPS=4) 16 CPUs per NUMA zone (64 cores total) 2 x Dual port 100gbps Mellanox Technologies ConnectX-5 Ex EN NIC The test machine is configured such that a single interface has 8 RX queues. The queues' IRQs and memcached are pinned to CPUs that are NUMA-local to the interface which is under test. The NIC's interrupt coalescing configuration is left at boot-time defaults. Results: Results are shown below. The mechanism added by this series is represented by the 'suspend' cases. Data presented shows a summary over nearly 10 runs of each test case [8] using the scripts on github [7]. For latency, the median is shown. For throughput and CPU utilization, the average is shown. The results also include cycles-per-query (cpq) and instruction-per-query (ipq) metrics, following the methodology proposed in [2], to augment the CPU utilization numbers, which could be skewed due to frequency scaling. We find that this does not appear to be the case as CPU utilization and low-level metrics show similar trends. These results were captured using the scripts on github [7] to illustrate how this approach compares with other pre-existing mechanisms. This data is not to be interpreted as scientific data captured in a fully isolated lab setting, but instead as best effort, illustrative information comparing and contrasting tradeoffs. The absolute QPS results shift between submissions, but the relative differences are equivalent. As patches are rebased, several factors likely influence overall performance. Compare: - Throughput (MAX) and latencies of base vs suspend. - CPU usage of napibusy and fullbusy during lower load (200K, 400K for example) vs suspend. - Latency of the defer variants vs suspend as timeout and load increases. - suspend0, which sets defer_hard_irqs and gro_flush_timeout to 0, has nearly the same performance as the base case (this is FAQ item #1). The overall takeaway is that the suspend variants provide a superior combination of high throughput, low latency, and low cpu utilization compared to all other variants. Each of the suspend variants works very well, but some fine-tuning between latency and cpu utilization is still possible by tuning the small timeout (gro_flush_timeout). Note: we've reorganized the results to make comparison among testcases with the same load easier. testcase load qps avglat 95%lat 99%lat cpu cpq ipq base 200K 199946 112 239 416 26 12973 11343 defer10 200K 199971 54 124 142 29 19412 17460 defer20 200K 199986 60 130 153 26 15644 14095 defer50 200K 200025 79 144 182 23 12122 11632 defer200 200K 199999 164 254 309 19 8923 9635 fullbusy 200K 199998 46 118 133 100 43658 23133 napibusy 200K 199983 100 237 277 56 24840 24716 suspend0 200K 200020 105 249 432 30 14264 11796 suspend10 200K 199950 53 123 141 32 19518 16903 suspend20 200K 200037 58 126 151 30 16426 14736 suspend50 200K 199961 73 136 177 26 13310 12633 suspend200 200K 199998 149 251 306 21 9566 10203 testcase load qps avglat 95%lat 99%lat cpu cpq ipq base 400K 400014 139 269 707 41 9476 9343 defer10 400K 400016 59 133 166 53 13991 12989 defer20 400K 399952 67 140 172 47 12063 11644 defer50 400K 400007 87 162 198 39 9384 9880 defer200 400K 399979 181 274 330 31 7089 8430 fullbusy 400K 399987 50 123 156 100 21827 16037 napibusy 400K 400014 76 222 272 83 18185 16529 suspend0 400K 400015 127 350 776 47 10699 9603 suspend10 400K 400023 57 129 164 54 13758 13178 suspend20 400K 400043 62 135 169 49 12071 11826 suspend50 400K 400071 76 149 186 42 10011 10301 suspend200 400K 399961 154 269 327 34 7827 8774 testcase load qps avglat 95%lat 99%lat cpu cpq ipq base 600K 599951 149 266 574 61 9265 8876 defer10 600K 600006 71 147 203 76 11866 10936 defer20 600K 600123 76 152 203 66 10430 10342 defer50 600K 600162 95 172 217 54 8526 9142 defer200 600K 599942 200 301 357 46 6977 8212 fullbusy 600K 599990 55 127 177 100 14551 13983 napibusy 600K 600035 63 160 250 96 13937 14140 suspend0 600K 599903 127 320 732 68 10166 8963 suspend10 600K 599908 63 137 192 69 10902 11100 suspend20 600K 599961 66 141 194 65 9976 10370 suspend50 600K 599973 80 159 204 57 8678 9381 suspend200 600K 600010 157 277 346 48 7133 8381 testcase load qps avglat 95%lat 99%lat cpu cpq ipq base 800K 800039 181 300 536 87 9585 8304 defer10 800K 800038 181 530 939 96 10564 8970 defer20 800K 800029 112 225 329 90 10056 8935 defer50 800K 799999 120 208 296 82 9234 8562 defer200 800K 800066 227 338 401 63 7117 8129 fullbusy 800K 800040 61 134 190 100 10913 12608 napibusy 800K 799944 64 141 214 99 10828 12588 suspend0 800K 799911 126 248 509 85 9346 8498 suspend10 800K 800006 69 143 200 83 9410 9845 suspend20 800K 800120 74 150 207 78 8786 9454 suspend50 800K 799989 87 168 224 71 7946 8833 suspend200 800K 799987 160 292 357 62 6923 8229 testcase load qps avglat 95%lat 99%lat cpu cpq ipq base 1000K 906879 4079 5751 6216 98 9496 7904 defer10 1000K 860849 3643 6274 6730 99 10040 8676 defer20 1000K 896063 3298 5840 6349 98 9620 8237 defer50 1000K 919782 2962 5513 5807 97 9284 7951 defer200 1000K 970941 3059 5348 5984 95 8593 7959 fullbusy 1000K 999950 70 150 207 100 8732 10777 napibusy 1000K 999996 78 154 223 100 8722 10656 suspend0 1000K 949706 2666 5770 6660 99 9071 8046 suspend10 1000K 1000024 80 160 220 92 8137 9035 suspend20 1000K 1000059 83 165 226 89 7850 8804 suspend50 1000K 999955 95 180 240 84 7411 8459 suspend200 1000K 999914 163 299 366 77 6833 8078 testcase load qps avglat 95%lat 99%lat cpu cpq ipq base MAX 1037654 4184 5453 5810 100 8411 7938 defer10 MAX 905607 4840 6151 6380 100 9639 8431 defer20 MAX 986463 4455 5594 5796 100 8848 8110 defer50 MAX 1077030 4000 5073 5299 100 8104 7920 defer200 MAX 1040728 4152 5385 5765 100 8379 7849 fullbusy MAX 1247536 3518 3935 3984 100 6998 7930 napibusy MAX 1136310 3799 7756 9964 100 7670 7877 suspend0 MAX 1057509 4132 5724 6185 100 8253 7918 suspend10 MAX 1215147 3580 3957 4041 100 7185 7944 suspend20 MAX 1216469 3576 3953 3988 100 7175 7950 suspend50 MAX 1215871 3577 3961 4075 100 7181 7949 suspend200 MAX 1216882 3556 3951 3988 100 7175 7955 ~ FAQ - Why is a new parameter needed? Does irq_suspend_timeout override gro_flush_timeout? Using the suspend mechanism causes the system to alternate between polling mode and irq-driven packet delivery. During busy periods, irq_suspend_timeout overrides gro_flush_timeout and keeps the system busy polling, but when epoll finds no events, the setting of gro_flush_timeout and napi_defer_hard_irqs determine the next step. There are essentially three possible loops for network processing and packet delivery: 1) hardirq -> softirq -> napi poll; basic interrupt delivery 2) timer -> softirq -> napi poll; deferred irq processing 3) epoll -> busy-poll -> napi poll; busy looping Loop 2 can take control from Loop 1, if gro_flush_timeout and napi_defer_hard_irqs are set. If gro_flush_timeout and napi_defer_hard_irqs are set, Loops 2 and 3 "wrestle" with each other for control. During busy periods, irq_suspend_timeout is used as timer in Loop 2, which essentially tilts this in favour of Loop 3. If gro_flush_timeout and napi_defer_hard_irqs are not set, Loop 3 cannot take control from Loop 1. Therefore, setting gro_flush_timeout and napi_defer_hard_irqs is the recommended usage, because otherwise setting irq_suspend_timeout might not have any discernible effect. This is shown in the results above: compare suspend0 with the base case. Note that the lack of napi_defer_hard_irqs and gro_flush_timeout produce similar results for both, which encourages the use of napi_defer_hard_irqs and gro_flush_timeout in addition to irq_suspend_timeout. - Can the new timeout value be threaded through the new epoll ioctl ? It is possible, but presents challenges for userspace. User applications must ensure that the file descriptors added to epoll contexts have the same NAPI ID to support busy polling. An epoll context is not permanently tied to any particular NAPI ID. So, a user application could decide to clear the file descriptors from the context and add a new set of file descriptors with a different NAPI ID to the context. Busy polling would work as expected, but the meaning of the suspend timeout becomes ambiguous because IRQs are not inherently associated with epoll contexts, but rather with the NAPI. The user program would need to reissue the ioctl to set the irq_suspend_timeout, but the napi_defer_hard_irqs and gro_flush_timeout settings would come from the NAPI's napi_config (which are set either by sysfs or by netlink). Such an interface seems awkard to use from a user perspective. Further, IRQs are related to NAPIs, which is why they are stored in the napi_config space. Putting the irq_suspend_timeout in the epoll context while other IRQ deferral mechanisms remain in the NAPI's napi_config space seems like an odd design choice. We've opted to keep all of the IRQ deferral parameters together and place the irq_suspend_timeout in napi_config. This has nice benefits for userspace: if a user app were to remove all file descriptors from an epoll context and add new file descriptors with a new NAPI ID, the correct suspend timeout for that NAPI ID would be used automatically without the user application needing to do anything (like re-issuing an ioctl, for example). All IRQ deferral related parameters are in one place and can all be set the same way: with netlink. - Can irq suspend be built by combining NIC coalescing and gro_flush_timeout ? No. The problem is that the long timeout must engage if and only if prefer-busy is active. When using NIC coalescing for the short timeout (without napi_defer_hard_irqs/gro_flush_timeout), an interrupt after an idle period will trigger softirq, which will run napi polling. At this point, prefer-busy is not active, so NIC interrupts would be re-enabled. Then it is not possible for the longer timeout to interject to switch control back to polling. In other words, only by using the software timer for the short timeout, it is possible to extend the timeout without having to reprogram the NIC timer or reach down directly and disable interrupts. Using gro_flush_timeout for the long timeout also has problems, for the same underlying reason. In the current napi implementation, gro_flush_timeout is not tied to prefer-busy. We'd either have to change that and in the process modify the existing deferral mechanism, or introduce a state variable to determine whether gro_flush_timeout is used as long timeout for irq suspend or whether it is used for its default purpose. In an earlier version, we did try something similar to the latter and made it work, but it ends up being a lot more convoluted than our current proposal. - Isn't it already possible to combine busy looping with irq deferral? Yes, in fact enabling irq deferral via napi_defer_hard_irqs and gro_flush_timeout is a precondition for prefer_busy_poll to have an effect. If the application also uses a tight busy loop with essentially nonblocking epoll_wait (accomplished with a very short timeout parameter), this is the fullbusy case shown in the results. An application using blocking epoll_wait is shown as the napibusy case in the results. It's a hybrid approach that provides limited latency benefits compared to the base case and plain irq deferral, but not as good as fullbusy or suspend. ~ Special thanks Several people were involved in earlier stages of the development of this mechanism whom we'd like to thank: - Peter Cai (CC'd), for the initial kernel patch and his contributions to the paper. - Mohammadamin Shafie (CC'd), for testing various versions of the kernel patch and providing helpful feedback. Thanks, Martin and Joe [1]: https://lore.kernel.org/netdev/20240812125717.413108-1-jdamato@fastly.com/ [2]: https://doi.org/10.1145/3626780 [3]: https://github.com/memcached/memcached/blob/master/doc/napi_ids.txt [4]: https://github.com/leverich/mutilate [5]: https://raw.githubusercontent.com/martinkarsten/irqsuspend/main/patches/mem… [6]: https://raw.githubusercontent.com/martinkarsten/irqsuspend/main/patches/lib… [7]: https://github.com/martinkarsten/irqsuspend [8]: https://github.com/martinkarsten/irqsuspend/tree/main/results v9: - Addresses Willem's feedback on the selftests in patch 5 by fixing the SPDX-License-Identifier, moving constants into variables in the test script, reducing code duplication, shortening long lines, and renaming variables to be more reader friendly. In the C test file, added a comment explaining the if def blob and changed a few types for strtoul. v8: https://lore.kernel.org/netdev/20241108045337.292905-1-jdamato@fastly.com/ - Update patch 2 to drop the exports, as requested by Jakub. v7: https://lore.kernel.org/netdev/20241108023912.98416-1-jdamato@fastly.com/ - Jakub noted that patch 2 adds unnecessary complexity by checking the suspend timeout in the NAPI loop. This makes the code more complicated and difficult to reason about. He's right; we've dropped patch 2 which simplifies this series. - Updated the cover letter with a full re-run of all test cases. - Updated FAQ #2. v6: https://lore.kernel.org/netdev/20241104215542.215919-1-jdamato@fastly.com/ - Updated the cover letter with a full re-run of all test cases, including a new case suspend0, as requested by Sridhar previously. - Updated the kernel documentation in patch 7 as suggested by Bagas Sanjaya, which improved the htmldoc output. v5: https://lore.kernel.org/netdev/20241103052421.518856-1-jdamato@fastly.com/ - Adjusted patch 5 to only suspend IRQs when ep_send_events returns a positive return value. This issue was pointed out by Hillf Danton. - Updated the commit message of patch 6 which still mentioned netcat, despite the code being updated in v4 to replace it with socat and fixed misspelling of netdevsim. - Fixed a minor typo in patch 7 and removed an unnecessary paragraph. - Added Sridhar Samudrala's Reviewed-by to patch 1-5 and 7. v4: https://lore.kernel.org/netdev/20241102005214.32443-1-jdamato@fastly.com/ - Added a new FAQ item to cover letter. - Updated patch 6 to use socat instead of nc in busy_poll_test.sh and updated busy_poller.c to use netlink directly to configure napi params. - Updated the kernel documentation in patch 7 to include more details. - Dropped Stanislav's Acked-by and Bagas' Reviewed-by from patch 7 since the documentation was updated. v3: https://lore.kernel.org/netdev/20241101004846.32532-1-jdamato@fastly.com/ - Added Stanislav Fomichev's Acked-by to every patch except the newly added selftest. - Added Bagas Sanjaya's Reviewed-by to the documentation patch. - Fixed the commit message of patch 2 to remove a reference to the now non-existent sysfs setting. - Added a self test which tests both "regular" busy poll and busy poll with suspend enabled. This was added as patch 6 as requested by Paolo. netdevsim was chosen instead of veth due to netdevsim's pre-existing support for netdev-genl. See the commit message of patch 6 for more details. v2: https://lore.kernel.org/bpf/20241021015311.95468-1-jdamato@fastly.com/ - Cover letter updated, including a re-run of test data. - Patch 1 rewritten to use netdev-genl instead of sysfs. - Patch 3 updated with a comment added to napi_resume_irqs. - Patch 4 rebased to apply now that commit b9ca079dd6b0 ("eventpoll: Annotate data-race of busy_poll_usecs") has been picked up from VFS. - Patch 6 updated the kernel documentation. rfc -> v1: - Cover letter updated to include more details. - Patch 1 updated to remove the documentation added. This was moved to patch 6 with the rest of the docs (see below). - Patch 5 updated to fix an error uncovered by the kernel build robot. See patch 5's changelog for more details. - Patch 6 added which updates kernel documentation. Joe Damato (2): selftests: net: Add busy_poll_test docs: networking: Describe irq suspension Martin Karsten (4): net: Add napi_struct parameter irq_suspend_timeout net: Add control functions for irq suspension eventpoll: Trigger napi_busy_loop, if prefer_busy_poll is set eventpoll: Control irq suspension for prefer_busy_poll Documentation/netlink/specs/netdev.yaml | 7 + Documentation/networking/napi.rst | 170 ++++++++- fs/eventpoll.c | 36 +- include/linux/netdevice.h | 2 + include/net/busy_poll.h | 3 + include/uapi/linux/netdev.h | 1 + net/core/dev.c | 39 ++ net/core/dev.h | 25 ++ net/core/netdev-genl-gen.c | 5 +- net/core/netdev-genl.c | 12 + tools/include/uapi/linux/netdev.h | 1 + tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 3 +- tools/testing/selftests/net/busy_poll_test.sh | 165 +++++++++ tools/testing/selftests/net/busy_poller.c | 346 ++++++++++++++++++ 15 files changed, 809 insertions(+), 7 deletions(-) create mode 100755 tools/testing/selftests/net/busy_poll_test.sh create mode 100644 tools/testing/selftests/net/busy_poller.c base-commit: dc7c381bb8649e3701ed64f6c3e55316675904d7 -- 2.25.1

3 weeks, 4 days

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[PATCH 0/3] HID: multitouch: set INPUT_PROP_PRESSUREPAD on compatible touchpads

by Peter Hutterer

Note: this requires INPUT_PROP_PRESSUREPAD [1] which is not yet available in Linus' tree but it is in Dmitry's for-linus tree. Nicely enough MS defines a button type for a pressurepad touchpad [2] and it looks like most touchpad vendors fill this in. The selftests require a bit of prep work (and a hack for the test itself) - hidtools 0.12 requires python-libevdev 0.13 which in turn provides constructors for unknown properties. [1] https://lore.kernel.org/linux-input/20251030011735.GA969565@quokka/T/#m9d9b… [2] https://learn.microsoft.com/en-us/windows-hardware/design/component-guideli… Signed-off-by: Peter Hutterer <peter.hutterer(a)who-t.net> --- Peter Hutterer (3): selftests/hid: require hidtools 0.12 selftests/hid: use a enum class for the different button types HID: multitouch: set INPUT_PROP_PRESSUREPAD based on Digitizer/Button Type drivers/hid/hid-multitouch.c | 12 ++++- tools/testing/selftests/hid/tests/conftest.py | 14 +++++ .../testing/selftests/hid/tests/test_multitouch.py | 61 +++++++++++++++++----- 3 files changed, 73 insertions(+), 14 deletions(-) --- base-commit: 2bc4c50a42f8b83f611d0475598dc72740e87640 change-id: 20251111-wip-hid-pressurepad-8a800cdf1813 Best regards, -- Peter Hutterer <peter.hutterer(a)who-t.net>

3 weeks, 4 days

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[RFC PATCH] rust: doctests: Number tests by line numerically, not lexicographically.

by David Gow

The rust doctests are numbered -- instead of named with the line number -- in order to keep them moderately consistent even as the source file changes. However, the test numbers are generated by sorting the file/line strings, and so the line numbers were sorted as strings, not integers. So, for instance, a test on line 7 would sort in-between one on line 65 and one on line 75. Instead, parse the numbers as an integer, and sort based on that. This is a bit slower, uglier, and will break things once, but I suspect is worth it (at least until we have a better solution). Signed-off-by: David Gow <davidgow(a)google.com> --- This is a pretty unpolished, likely-unidiomatic patch to work around the test numbering being horrible. I have three questions before I decide if this is worth continuing with: 1. Is it worth renumbering all of the tests (hopefully just once), or would that break too many people's test histories? 2. Is there a better way of doing this in Rust? I can think of ways which might be nicer if the whole thing is refactored somewhat seriously, but if there's an easy numeric sort on strings, that'd be much easier. 3. Should we wait until after all or some of the changes to the test generation? Does the new --output-format=doctest option make this easier/harder/different? Does anyone have opinions/advice on those (or, indeed, on anything else)? Cheers, -- David --- scripts/rustdoc_test_gen.rs | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs index be0561049660..60b0bbfb1896 100644 --- a/scripts/rustdoc_test_gen.rs +++ b/scripts/rustdoc_test_gen.rs @@ -116,7 +116,19 @@ fn main() { .collect::<Vec<_>>(); // Sort paths. - paths.sort(); + paths.sort_by(|a, b|{ + let a_name = a.file_name().unwrap().to_str().unwrap().to_string(); + let (a_file, a_line) = a_name.rsplit_once('_').unwrap().0.rsplit_once('_').unwrap(); + let a_line_no = a_line.parse::<u64>().unwrap(); + let b_name = b.file_name().unwrap().to_str().unwrap().to_string(); + let (b_file, b_line) = b_name.rsplit_once('_').unwrap().0.rsplit_once('_').unwrap(); + let b_line_no = b_line.parse::<u64>().unwrap(); + + match a_file.cmp(b_file) { + std::cmp::Ordering::Equal => a_line_no.cmp(&b_line_no), + order => order, + } + }); let mut rust_tests = String::new(); let mut c_test_declarations = String::new(); -- 2.52.0.322.g1dd061c0dc-goog

3 weeks, 4 days

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[PATCH] kunit: Enforce task execution in {soft,hard}irq contexts

by David Gow

The kunit_run_irq_test() helper allows a function to be run in hardirq and softirq contexts (in addition to the task context). It does this by running the user-provided function concurrently in the three contexts, until either a timeout has expired or a number of iterations have completed in the normal task context. However, on setups where the initialisation of the hardirq and softirq contexts (or, indeed, the scheduling of those tasks) is significantly slower than the function execution, it's possible for that number of iterations to be exceeded before any runs in irq contexts actually occur. This occurs with the polyval.test_polyval_preparekey_in_irqs test, which runs 20000 iterations of the relatively fast preparekey function, and therefore fails often under many UML, 32-bit arm, m68k and other environments. Instead, ensure that the max_iterations limit counts executions in all three contexts, and requires at least one of each. This will cause the test to continue iterating until at least the irq contexts have been tested, or the 1s wall-clock limit has been exceeded. This causes the test to pass in all of my environments. In so doing, we also update the task counters to atomic ints, to better match both the 'int' max_iterations input, and to ensure they are correctly updated across contexts. Finally, we also fix a few potential assertion messages to be less-specific to the original crypto usecases. Fixes: b41dc83f0790 ("kunit, lib/crypto: Move run_irq_test() to common header") Signed-off-by: David Gow <davidgow(a)google.com> --- include/kunit/run-in-irq-context.h | 41 ++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 13 deletions(-) diff --git a/include/kunit/run-in-irq-context.h b/include/kunit/run-in-irq-context.h index 108e96433ea4..4d25aee0de6e 100644 --- a/include/kunit/run-in-irq-context.h +++ b/include/kunit/run-in-irq-context.h @@ -20,8 +20,8 @@ struct kunit_irq_test_state { bool task_func_reported_failure; bool hardirq_func_reported_failure; bool softirq_func_reported_failure; - unsigned long hardirq_func_calls; - unsigned long softirq_func_calls; + atomic_t hardirq_func_calls; + atomic_t softirq_func_calls; struct hrtimer timer; struct work_struct bh_work; }; @@ -32,7 +32,7 @@ static enum hrtimer_restart kunit_irq_test_timer_func(struct hrtimer *timer) container_of(timer, typeof(*state), timer); WARN_ON_ONCE(!in_hardirq()); - state->hardirq_func_calls++; + atomic_inc(&state->hardirq_func_calls); if (!state->func(state->test_specific_state)) state->hardirq_func_reported_failure = true; @@ -48,7 +48,7 @@ static void kunit_irq_test_bh_work_func(struct work_struct *work) container_of(work, typeof(*state), bh_work); WARN_ON_ONCE(!in_serving_softirq()); - state->softirq_func_calls++; + atomic_inc(&state->softirq_func_calls); if (!state->func(state->test_specific_state)) state->softirq_func_reported_failure = true; @@ -59,7 +59,10 @@ static void kunit_irq_test_bh_work_func(struct work_struct *work) * hardirq context concurrently, and reports a failure to KUnit if any * invocation of @func in any context returns false. @func is passed * @test_specific_state as its argument. At most 3 invocations of @func will - * run concurrently: one in each of task, softirq, and hardirq context. + * run concurrently: one in each of task, softirq, and hardirq context. @func + * will continue running until either @max_iterations calls have been made (so + * long as at least one each runs in task, softirq, and hardirq contexts), or + * one second has passed. * * The main purpose of this interrupt context testing is to validate fallback * code paths that run in contexts where the normal code path cannot be used, @@ -85,6 +88,10 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), .test_specific_state = test_specific_state, }; unsigned long end_jiffies; + int hardirq_calls, softirq_calls; + bool allctx = false; + + max_iterations = 1; /* * Set up a hrtimer (the way we access hardirq context) and a work @@ -94,14 +101,22 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); INIT_WORK_ONSTACK(&state.bh_work, kunit_irq_test_bh_work_func); - /* Run for up to max_iterations or 1 second, whichever comes first. */ + /* Run for up to max_iterations (including at least one task, softirq, + * and hardirq), or 1 second, whichever comes first. + */ end_jiffies = jiffies + HZ; hrtimer_start(&state.timer, KUNIT_IRQ_TEST_HRTIMER_INTERVAL, HRTIMER_MODE_REL_HARD); - for (int i = 0; i < max_iterations && !time_after(jiffies, end_jiffies); - i++) { + for (int task_calls = 0, calls = 0; + ((calls < max_iterations) || !allctx) && !time_after(jiffies, end_jiffies); + task_calls++) { if (!func(test_specific_state)) state.task_func_reported_failure = true; + + hardirq_calls = atomic_read(&state.hardirq_func_calls); + softirq_calls = atomic_read(&state.softirq_func_calls); + calls = task_calls + hardirq_calls + softirq_calls; + allctx = (task_calls > 0) && (hardirq_calls > 0) && (softirq_calls > 0); } /* Cancel the timer and work. */ @@ -109,21 +124,21 @@ static inline void kunit_run_irq_test(struct kunit *test, bool (*func)(void *), flush_work(&state.bh_work); /* Sanity check: the timer and BH functions should have been run. */ - KUNIT_EXPECT_GT_MSG(test, state.hardirq_func_calls, 0, + KUNIT_EXPECT_GT_MSG(test, atomic_read(&state.hardirq_func_calls), 0, "Timer function was not called"); - KUNIT_EXPECT_GT_MSG(test, state.softirq_func_calls, 0, + KUNIT_EXPECT_GT_MSG(test, atomic_read(&state.softirq_func_calls), 0, "BH work function was not called"); /* Check for incorrect hash values reported from any context. */ KUNIT_EXPECT_FALSE_MSG( test, state.task_func_reported_failure, - "Incorrect hash values reported from task context"); + "Failure reported from task context"); KUNIT_EXPECT_FALSE_MSG( test, state.hardirq_func_reported_failure, - "Incorrect hash values reported from hardirq context"); + "Failure reported from hardirq context"); KUNIT_EXPECT_FALSE_MSG( test, state.softirq_func_reported_failure, - "Incorrect hash values reported from softirq context"); + "Failure reported from softirq context"); } #endif /* _KUNIT_RUN_IN_IRQ_CONTEXT_H */ -- 2.52.0.322.g1dd061c0dc-goog

3 weeks, 4 days

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[PATCH RESEND] x86: checksum: Fix unaligned checksums on < i686

by David Gow

The checksum_32 code was originally written to only handle 2-byte aligned buffers, but was later extended to support arbitrary alignment. However, the non-PPro variant doesn't apply the carry before jumping to the 2- or 4-byte aligned versions, which clear CF. This causes the new checksum_kunit test to fail, as it runs with a large number of different possible alignments and both with and without carries. For example: ./tools/testing/kunit/kunit.py run --arch i386 --kconfig_add CONFIG_M486=y checksum Gives: KTAP version 1 # Subtest: checksum 1..3 ok 1 test_csum_fixed_random_inputs # test_csum_all_carry_inputs: ASSERTION FAILED at lib/checksum_kunit.c:267 Expected result == expec, but result == 65281 (0xff01) expec == 65280 (0xff00) not ok 2 test_csum_all_carry_inputs # test_csum_no_carry_inputs: ASSERTION FAILED at lib/checksum_kunit.c:314 Expected result == expec, but result == 65535 (0xffff) expec == 65534 (0xfffe) not ok 3 test_csum_no_carry_inputs With this patch, it passes. KTAP version 1 # Subtest: checksum 1..3 ok 1 test_csum_fixed_random_inputs ok 2 test_csum_all_carry_inputs ok 3 test_csum_no_carry_inputs I also tested it on a real 486DX2, with the same results. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: David Gow <davidgow(a)google.com> --- Re-sending this from [1]. While there's an argument that the whole 32-bit checksum code could do with rewriting, it's: (a) worth fixing before someone takes the time to rewrite it, and (b) worth any future rewrite starting from a point where the tests pass I don't think there should be any downside to this fix: it only affects ancient computers, and adds a single instruction which isn't in a loop. Cheers, -- David [1]: https://lore.kernel.org/lkml/20230704083206.693155-2-davidgow@google.com/ --- arch/x86/lib/checksum_32.S | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/lib/checksum_32.S b/arch/x86/lib/checksum_32.S index 68f7fa3e1322..a5123b29b403 100644 --- a/arch/x86/lib/checksum_32.S +++ b/arch/x86/lib/checksum_32.S @@ -62,6 +62,7 @@ SYM_FUNC_START(csum_partial) jl 8f movzbl (%esi), %ebx adcl %ebx, %eax + adcl $0, %eax roll $8, %eax inc %esi testl $2, %esi -- 2.45.2.1089.g2a221341d9-goog

3 weeks, 4 days

2
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[PATCH v12] exec: Fix dead-lock in de_thread with ptrace_attach

by Bernd Edlinger

This introduces signal->exec_bprm, which is used to fix the case when at least one of the sibling threads is traced, and therefore the trace process may dead-lock in ptrace_attach, but de_thread will need to wait for the tracer to continue execution. The solution is to detect this situation and allow ptrace_attach to continue by temporarily releasing the cred_guard_mutex, while de_thread() is still waiting for traced zombies to be eventually released by the tracer. In the case of the thread group leader we only have to wait for the thread to become a zombie, which may also need co-operation from the tracer due to PTRACE_O_TRACEEXIT. When a tracer wants to ptrace_attach a task that already is in execve, we simply retry the ptrace_may_access check while temporarily installing the new credentials and dumpability which are about to be used after execve completes. If the ptrace_attach happens on a thread that is a sibling-thread of the thread doing execve, it is sufficient to check against the old credentials, as this thread will be waited for, before the new credentials are installed. Other threads die quickly since the cred_guard_mutex is released, but a deadly signal is already pending. In case the mutex_lock_killable misses the signal, the non-zero current->signal->exec_bprm makes sure they release the mutex immediately and return with -ERESTARTNOINTR. This means there is no API change, unlike the previous version of this patch which was discussed here: https://lore.kernel.org/lkml/b6537ae6-31b1-5c50-f32b-8b8332ace882@hotmail.d… See tools/testing/selftests/ptrace/vmaccess.c for a test case that gets fixed by this change. Note that since the test case was originally designed to test the ptrace_attach returning an error in this situation, the test expectation needed to be adjusted, to allow the API to succeed at the first attempt. Signed-off-by: Bernd Edlinger <bernd.edlinger(a)hotmail.de> --- fs/exec.c | 69 ++++++++++++++++------- fs/proc/base.c | 6 ++ include/linux/cred.h | 1 + include/linux/sched/signal.h | 18 ++++++ kernel/cred.c | 28 +++++++-- kernel/ptrace.c | 32 +++++++++++ kernel/seccomp.c | 12 +++- tools/testing/selftests/ptrace/vmaccess.c | 23 +++++--- 8 files changed, 155 insertions(+), 34 deletions(-) v10: Changes to previous version, make the PTRACE_ATTACH retun -EAGAIN, instead of execve return -ERESTARTSYS. Added some lessions learned to the description. v11: Check old and new credentials in PTRACE_ATTACH again without changing the API. Note: I got actually one response from an automatic checker to the v11 patch, https://lore.kernel.org/lkml/202107121344.wu68hEPF-lkp@intel.com/ which is complaining about: >> kernel/ptrace.c:425:26: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct cred const *old_cred @@ got struct cred const [noderef] __rcu *real_cred @@ 417 struct linux_binprm *bprm = task->signal->exec_bprm; 418 const struct cred *old_cred; 419 struct mm_struct *old_mm; 420 421 retval = down_write_killable(&task->signal->exec_update_lock); 422 if (retval) 423 goto unlock_creds; 424 task_lock(task); > 425 old_cred = task->real_cred; v12: Essentially identical to v11. - Fixed a minor merge conflict in linux v5.17, and fixed the above mentioned nit by adding __rcu to the declaration. - re-tested the patch with all linux versions from v5.11 to v6.6 v10 was an alternative approach which did imply an API change. But I would prefer to avoid such an API change. The difficult part is getting the right dumpability flags assigned before de_thread starts, hope you like this version. If not, the v10 is of course also acceptable. Thanks Bernd. diff --git a/fs/exec.c b/fs/exec.c index 2f2b0acec4f0..902d3b230485 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1041,11 +1041,13 @@ static int exec_mmap(struct mm_struct *mm) return 0; } -static int de_thread(struct task_struct *tsk) +static int de_thread(struct task_struct *tsk, struct linux_binprm *bprm) { struct signal_struct *sig = tsk->signal; struct sighand_struct *oldsighand = tsk->sighand; spinlock_t *lock = &oldsighand->siglock; + struct task_struct *t = tsk; + bool unsafe_execve_in_progress = false; if (thread_group_empty(tsk)) goto no_thread_group; @@ -1068,6 +1070,19 @@ static int de_thread(struct task_struct *tsk) if (!thread_group_leader(tsk)) sig->notify_count--; + while_each_thread(tsk, t) { + if (unlikely(t->ptrace) + && (t != tsk->group_leader || !t->exit_state)) + unsafe_execve_in_progress = true; + } + + if (unlikely(unsafe_execve_in_progress)) { + spin_unlock_irq(lock); + sig->exec_bprm = bprm; + mutex_unlock(&sig->cred_guard_mutex); + spin_lock_irq(lock); + } + while (sig->notify_count) { __set_current_state(TASK_KILLABLE); spin_unlock_irq(lock); @@ -1158,6 +1173,11 @@ static int de_thread(struct task_struct *tsk) release_task(leader); } + if (unlikely(unsafe_execve_in_progress)) { + mutex_lock(&sig->cred_guard_mutex); + sig->exec_bprm = NULL; + } + sig->group_exec_task = NULL; sig->notify_count = 0; @@ -1169,6 +1189,11 @@ static int de_thread(struct task_struct *tsk) return 0; killed: + if (unlikely(unsafe_execve_in_progress)) { + mutex_lock(&sig->cred_guard_mutex); + sig->exec_bprm = NULL; + } + /* protects against exit_notify() and __exit_signal() */ read_lock(&tasklist_lock); sig->group_exec_task = NULL; @@ -1253,6 +1278,24 @@ int begin_new_exec(struct linux_binprm * bprm) if (retval) return retval; + /* If the binary is not readable then enforce mm->dumpable=0 */ + would_dump(bprm, bprm->file); + if (bprm->have_execfd) + would_dump(bprm, bprm->executable); + + /* + * Figure out dumpability. Note that this checking only of current + * is wrong, but userspace depends on it. This should be testing + * bprm->secureexec instead. + */ + if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP || + is_dumpability_changed(current_cred(), bprm->cred) || + !(uid_eq(current_euid(), current_uid()) && + gid_eq(current_egid(), current_gid()))) + set_dumpable(bprm->mm, suid_dumpable); + else + set_dumpable(bprm->mm, SUID_DUMP_USER); + /* * Ensure all future errors are fatal. */ @@ -1261,7 +1304,7 @@ int begin_new_exec(struct linux_binprm * bprm) /* * Make this the only thread in the thread group. */ - retval = de_thread(me); + retval = de_thread(me, bprm); if (retval) goto out; @@ -1284,11 +1327,6 @@ int begin_new_exec(struct linux_binprm * bprm) if (retval) goto out; - /* If the binary is not readable then enforce mm->dumpable=0 */ - would_dump(bprm, bprm->file); - if (bprm->have_execfd) - would_dump(bprm, bprm->executable); - /* * Release all of the old mmap stuff */ @@ -1350,18 +1388,6 @@ int begin_new_exec(struct linux_binprm * bprm) me->sas_ss_sp = me->sas_ss_size = 0; - /* - * Figure out dumpability. Note that this checking only of current - * is wrong, but userspace depends on it. This should be testing - * bprm->secureexec instead. - */ - if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP || - !(uid_eq(current_euid(), current_uid()) && - gid_eq(current_egid(), current_gid()))) - set_dumpable(current->mm, suid_dumpable); - else - set_dumpable(current->mm, SUID_DUMP_USER); - perf_event_exec(); __set_task_comm(me, kbasename(bprm->filename), true); @@ -1480,6 +1506,11 @@ static int prepare_bprm_creds(struct linux_binprm *bprm) if (mutex_lock_interruptible(&current->signal->cred_guard_mutex)) return -ERESTARTNOINTR; + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + return -ERESTARTNOINTR; + } + bprm->cred = prepare_exec_creds(); if (likely(bprm->cred)) return 0; diff --git a/fs/proc/base.c b/fs/proc/base.c index ffd54617c354..0da9adfadb48 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2788,6 +2788,12 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, if (rv < 0) goto out_free; + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + rv = -ERESTARTNOINTR; + goto out_free; + } + rv = security_setprocattr(PROC_I(inode)->op.lsm, file->f_path.dentry->d_name.name, page, count); diff --git a/include/linux/cred.h b/include/linux/cred.h index f923528d5cc4..b01e309f5686 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -159,6 +159,7 @@ extern const struct cred *get_task_cred(struct task_struct *); extern struct cred *cred_alloc_blank(void); extern struct cred *prepare_creds(void); extern struct cred *prepare_exec_creds(void); +extern bool is_dumpability_changed(const struct cred *, const struct cred *); extern int commit_creds(struct cred *); extern void abort_creds(struct cred *); extern const struct cred *override_creds(const struct cred *); diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 0014d3adaf84..14df7073a0a8 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -234,9 +234,27 @@ struct signal_struct { struct mm_struct *oom_mm; /* recorded mm when the thread group got * killed by the oom killer */ + struct linux_binprm *exec_bprm; /* Used to check ptrace_may_access + * against new credentials while + * de_thread is waiting for other + * traced threads to terminate. + * Set while de_thread is executing. + * The cred_guard_mutex is released + * after de_thread() has called + * zap_other_threads(), therefore + * a fatal signal is guaranteed to be + * already pending in the unlikely + * event, that + * current->signal->exec_bprm happens + * to be non-zero after the + * cred_guard_mutex was acquired. + */ + struct mutex cred_guard_mutex; /* guard against foreign influences on * credential calculations * (notably. ptrace) + * Held while execve runs, except when + * a sibling thread is being traced. * Deprecated do not use in new code. * Use exec_update_lock instead. */ diff --git a/kernel/cred.c b/kernel/cred.c index 98cb4eca23fb..586cb6c7cf6b 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -433,6 +433,28 @@ static bool cred_cap_issubset(const struct cred *set, const struct cred *subset) return false; } +/** + * is_dumpability_changed - Will changing creds from old to new + * affect the dumpability in commit_creds? + * + * Return: false - dumpability will not be changed in commit_creds. + * Return: true - dumpability will be changed to non-dumpable. + * + * @old: The old credentials + * @new: The new credentials + */ +bool is_dumpability_changed(const struct cred *old, const struct cred *new) +{ + if (!uid_eq(old->euid, new->euid) || + !gid_eq(old->egid, new->egid) || + !uid_eq(old->fsuid, new->fsuid) || + !gid_eq(old->fsgid, new->fsgid) || + !cred_cap_issubset(old, new)) + return true; + + return false; +} + /** * commit_creds - Install new credentials upon the current task * @new: The credentials to be assigned @@ -467,11 +489,7 @@ int commit_creds(struct cred *new) get_cred(new); /* we will require a ref for the subj creds too */ /* dumpability changes */ - if (!uid_eq(old->euid, new->euid) || - !gid_eq(old->egid, new->egid) || - !uid_eq(old->fsuid, new->fsuid) || - !gid_eq(old->fsgid, new->fsgid) || - !cred_cap_issubset(old, new)) { + if (is_dumpability_changed(old, new)) { if (task->mm) set_dumpable(task->mm, suid_dumpable); task->pdeath_signal = 0; diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 443057bee87c..eb1c450bb7d7 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -20,6 +20,7 @@ #include <linux/pagemap.h> #include <linux/ptrace.h> #include <linux/security.h> +#include <linux/binfmts.h> #include <linux/signal.h> #include <linux/uio.h> #include <linux/audit.h> @@ -435,6 +436,28 @@ static int ptrace_attach(struct task_struct *task, long request, if (retval) goto unlock_creds; + if (unlikely(task->in_execve)) { + struct linux_binprm *bprm = task->signal->exec_bprm; + const struct cred __rcu *old_cred; + struct mm_struct *old_mm; + + retval = down_write_killable(&task->signal->exec_update_lock); + if (retval) + goto unlock_creds; + task_lock(task); + old_cred = task->real_cred; + old_mm = task->mm; + rcu_assign_pointer(task->real_cred, bprm->cred); + task->mm = bprm->mm; + retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS); + rcu_assign_pointer(task->real_cred, old_cred); + task->mm = old_mm; + task_unlock(task); + up_write(&task->signal->exec_update_lock); + if (retval) + goto unlock_creds; + } + write_lock_irq(&tasklist_lock); retval = -EPERM; if (unlikely(task->exit_state)) @@ -508,6 +531,14 @@ static int ptrace_traceme(void) { int ret = -EPERM; + if (mutex_lock_interruptible(&current->signal->cred_guard_mutex)) + return -ERESTARTNOINTR; + + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + return -ERESTARTNOINTR; + } + write_lock_irq(&tasklist_lock); /* Are we already being traced? */ if (!current->ptrace) { @@ -523,6 +554,7 @@ static int ptrace_traceme(void) } } write_unlock_irq(&tasklist_lock); + mutex_unlock(&current->signal->cred_guard_mutex); return ret; } diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 255999ba9190..b29bbfa0b044 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1955,9 +1955,15 @@ static long seccomp_set_mode_filter(unsigned int flags, * Make sure we cannot change seccomp or nnp state via TSYNC * while another thread is in the middle of calling exec. */ - if (flags & SECCOMP_FILTER_FLAG_TSYNC && - mutex_lock_killable(&current->signal->cred_guard_mutex)) - goto out_put_fd; + if (flags & SECCOMP_FILTER_FLAG_TSYNC) { + if (mutex_lock_killable(&current->signal->cred_guard_mutex)) + goto out_put_fd; + + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + goto out_put_fd; + } + } spin_lock_irq(&current->sighand->siglock); diff --git a/tools/testing/selftests/ptrace/vmaccess.c b/tools/testing/selftests/ptrace/vmaccess.c index 4db327b44586..3b7d81fb99bb 100644 --- a/tools/testing/selftests/ptrace/vmaccess.c +++ b/tools/testing/selftests/ptrace/vmaccess.c @@ -39,8 +39,15 @@ TEST(vmaccess) f = open(mm, O_RDONLY); ASSERT_GE(f, 0); close(f); - f = kill(pid, SIGCONT); - ASSERT_EQ(f, 0); + f = waitpid(-1, NULL, 0); + ASSERT_NE(f, -1); + ASSERT_NE(f, 0); + ASSERT_NE(f, pid); + f = waitpid(-1, NULL, 0); + ASSERT_EQ(f, pid); + f = waitpid(-1, NULL, 0); + ASSERT_EQ(f, -1); + ASSERT_EQ(errno, ECHILD); } TEST(attach) @@ -57,22 +64,24 @@ TEST(attach) sleep(1); k = ptrace(PTRACE_ATTACH, pid, 0L, 0L); - ASSERT_EQ(errno, EAGAIN); - ASSERT_EQ(k, -1); + ASSERT_EQ(k, 0); k = waitpid(-1, &s, WNOHANG); ASSERT_NE(k, -1); ASSERT_NE(k, 0); ASSERT_NE(k, pid); ASSERT_EQ(WIFEXITED(s), 1); ASSERT_EQ(WEXITSTATUS(s), 0); - sleep(1); - k = ptrace(PTRACE_ATTACH, pid, 0L, 0L); + k = waitpid(-1, &s, 0); + ASSERT_EQ(k, pid); + ASSERT_EQ(WIFSTOPPED(s), 1); + ASSERT_EQ(WSTOPSIG(s), SIGTRAP); + k = ptrace(PTRACE_CONT, pid, 0L, 0L); ASSERT_EQ(k, 0); k = waitpid(-1, &s, 0); ASSERT_EQ(k, pid); ASSERT_EQ(WIFSTOPPED(s), 1); ASSERT_EQ(WSTOPSIG(s), SIGSTOP); - k = ptrace(PTRACE_DETACH, pid, 0L, 0L); + k = ptrace(PTRACE_CONT, pid, 0L, 0L); ASSERT_EQ(k, 0); k = waitpid(-1, &s, 0); ASSERT_EQ(k, pid); -- 2.39.2

3 weeks, 4 days

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[PATCH v8 00/15] Consolidate iommu page table implementations (AMD)

by Jason Gunthorpe

[Joerg, can you put this and vtd in linux-next please. The vtd series is still good at v3 thanks] Currently each of the iommu page table formats duplicates all of the logic to maintain the page table and perform map/unmap/etc operations. There are several different versions of the algorithms between all the different formats. The io-pgtable system provides an interface to help isolate the page table code from the iommu driver, but doesn't provide tools to implement the common algorithms. This makes it very hard to improve the state of the pagetable code under the iommu domains as any proposed improvement needs to alter a large number of different driver code paths. Combined with a lack of software based testing this makes improvement in this area very hard. iommufd wants several new page table operations: - More efficient map/unmap operations, using iommufd's batching logic - unmap that returns the physical addresses into a batch as it progresses - cut that allows splitting areas so large pages can have holes poked in them dynamically (ie guestmemfd hitless shared/private transitions) - More agressive freeing of table memory to avoid waste - Fragmenting large pages so that dirty tracking can be more granular - Reassembling large pages so that VMs can run at full IO performance in migration/dirty tracking error flows - KHO integration for kernel live upgrade Together these are algorithmically complex enough to be a very significant task to go and implement in all the page table formats we support. Just the "server" focused drivers use almost all the formats (ARMv8 S1&S2 / x86 PAE / AMDv1 / VT-d SS / RISCV) Instead of doing the duplicated work, this series takes the first step to consolidate the algorithms into one places. In spirit it is similar to the work Christoph did a few years back to pull the redundant get_user_pages() implementations out of the arch code into core MM. This unlocked a great deal of improvement in that space in the following years. I would like to see the same benefit in iommu as well. My first RFC showed a bigger picture with all most all formats and more algorithms. This series reorganizes that to be narrowly focused on just enough to convert the AMD driver to use the new mechanism. kunit tests are provided that allow good testing of the algorithms and all formats on x86, nothing is arch specific. AMD is one of the simpler options as the HW is quite uniform with few different options/bugs while still requiring the complicated contiguous pages support. The HW also has a very simple range based invalidation approach that is easy to implement. The AMD v1 and AMD v2 page table formats are implemented bit for bit identical to the current code, tested using a compare kunit test that checks against the io-pgtable version (on github, see below). Updating the AMD driver to replace the io-pgtable layer with the new stuff is fairly straightforward now. The layering is fixed up in the new version so that all the invalidation goes through function pointers. Several small fixing patches have come out of this as I've been fixing the problems that the test suite uncovers in the current code, and implementing the fixed version in iommupt. On performance, there is a quite wide variety of implementation designs across all the drivers. Looking at some key performance across the main formats: iommu_map(): pgsz ,avg new,old ns, min new,old ns , min % (+ve is better) 2^12, 53,66 , 51,63 , 19.19 (AMDV1) 256*2^12, 386,1909 , 367,1795 , 79.79 256*2^21, 362,1633 , 355,1556 , 77.77 2^12, 56,62 , 52,59 , 11.11 (AMDv2) 256*2^12, 405,1355 , 357,1292 , 72.72 256*2^21, 393,1160 , 358,1114 , 67.67 2^12, 55,65 , 53,62 , 14.14 (VT-d second stage) 256*2^12, 391,518 , 332,512 , 35.35 256*2^21, 383,635 , 336,624 , 46.46 2^12, 57,65 , 55,63 , 12.12 (ARM 64 bit) 256*2^12, 380,389 , 361,369 , 2.02 256*2^21, 358,419 , 345,400 , 13.13 iommu_unmap(): pgsz ,avg new,old ns, min new,old ns , min % (+ve is better) 2^12, 69,88 , 65,85 , 23.23 (AMDv1) 256*2^12, 353,6498 , 331,6029 , 94.94 256*2^21, 373,6014 , 360,5706 , 93.93 2^12, 71,72 , 66,69 , 4.04 (AMDv2) 256*2^12, 228,891 , 206,871 , 76.76 256*2^21, 254,721 , 245,711 , 65.65 2^12, 69,87 , 65,82 , 20.20 (VT-d second stage) 256*2^12, 210,321 , 200,315 , 36.36 256*2^21, 255,349 , 238,342 , 30.30 2^12, 72,77 , 68,74 , 8.08 (ARM 64 bit) 256*2^12, 521,357 , 447,346 , -29.29 256*2^21, 489,358 , 433,345 , -25.25 * Above numbers include additional patches to remove the iommu_pgsize() overheads. gcc 13.3.0, i7-12700 This version provides fairly consistent performance across formats. ARM unmap performance is quite different because this version supports contiguous pages and uses a very different algorithm for unmapping. Though why it is so worse compared to AMDv1 I haven't figured out yet. The per-format commits include a more detailed chart. There is a second branch: https://github.com/jgunthorpe/linux/commits/iommu_pt_all Containing supporting work and future steps: - ARM short descriptor (32 bit), ARM long descriptor (64 bit) formats - RISCV format and RISCV conversion https://github.com/jgunthorpe/linux/commits/iommu_pt_riscv - Support for a DMA incoherent HW page table walker - VT-d second stage format and VT-d conversion https://github.com/jgunthorpe/linux/commits/iommu_pt_vtd - DART v1 & v2 format - Draft of a iommufd 'cut' operation to break down huge pages - A compare test that checks the iommupt formats against the iopgtable interface, including updating AMD to have a working iopgtable and patches to make VT-d have an iopgtable for testing. - A performance test to micro-benchmark map and unmap against iogptable My strategy is to go one by one for the drivers: - AMD driver conversion - RISCV page table and driver - Intel VT-d driver and VTDSS page table - Flushing improvements for RISCV - ARM SMMUv3 And concurrently work on the algorithm side: - debugfs content dump, like VT-d has - Cut support - Increase/Decrease page size support - map/unmap batching - KHO As we make more algorithm improvements the value to convert the drivers increases. This is on github: https://github.com/jgunthorpe/linux/commits/iommu_pt v8: - Remove unused to_amdv1pt/common_to_amdv1pt/to_x86_64_pt/common_to_x86_64_pt - Fix 32 bit udiv compile failure in the kunit v7: https://patch.msgid.link/r/0-v7-ab019a8791e2+175b8-iommu_pt_jgg@nvidia.com - Rebase to v6.18-rc2 - Improve comments and documentation - Add a few missed __sme_sets() for AMD CC - Rename pt_iommu_flush_ops -> pt_iommu_driver_ops VT-D -> VT-d pt_clear_entry -> pt_clear_entries pt_entry_write_is_dirty -> pt_entry_is_write_dirty pt_entry_set_write_clean -> pt_entry_make_write_clean - Tidy some of the map flow into a new function do_map() - Fix ffz64() v6: https://patch.msgid.link/r/0-v6-0fb54a1d9850+36b-iommu_pt_jgg@nvidia.com - Improve comments and documentation - Rename pt_entry_oa_full -> pt_entry_oa_exact pt_has_system_page -> pt_has_system_page_size pt_max_output_address_lg2 -> pt_max_oa_lg2 log2_f*() -> vaf* / oaf* / f*_t pt_item_fully_covered -> pt_entry_fully_covered - Fix missed constant propogation causing division - Consolidate debugging checks to pt_check_install_leaf_args() - Change collect->ignore_mapped to check_mapped - Shuffle some hunks around to more appropriate patches - Two new mini kunit tests v5: https://patch.msgid.link/r/0-v5-116c4948af3d+68091-iommu_pt_jgg@nvidia.com - Text grammar updates and kdoc fixes v4: https://patch.msgid.link/r/0-v4-0d6a6726a372+18959-iommu_pt_jgg@nvidia.com - Rebase on v6.16-rc3 - Integrate the HATS/HATDis changes - Remove 'default n' from kconfig - Remove unused 'PT_FIXED_TOP_LEVEL' - Improve comments and documentation - Fix some compile warnings from kbuild robots v3: https://patch.msgid.link/r/0-v3-a93aab628dbc+521-iommu_pt_jgg@nvidia.com - Rebase on v6.16-rc2 - s/PT_ENTRY_WORD_SIZE/PT_ITEM_WORD_SIZE/s to follow the language better - Comment and documentation updates - Add PT_TOP_PHYS_MASK to help manage alignment restrictions on the top pointer - Add missed force_aperture = true - Make pt_iommu_deinit() take care of the not-yet-inited error case internally as AMD/RISCV/VTD all shared this logic - Change gather_range() into gather_range_pages() so it also deals with the page list. This makes the following cache flushing series simpler - Fix missed update of unmap->unmapped in some error cases - Change clear_contig() to order the gather more logically - Remove goto from the error handling in __map_range_leaf() - s/log2_/oalog2_/ in places where the argument is an oaddr_t - Pass the pts to pt_table_install64/32() - Do not use SIGN_EXTEND for the AMDv2 page table because of Vasant's information on how PASID 0 works. v2: https://patch.msgid.link/r/0-v2-5c26bde5c22d+58b-iommu_pt_jgg@nvidia.com - AMD driver only, many code changes RFC: https://lore.kernel.org/all/0-v1-01fa10580981+1d-iommu_pt_jgg@nvidia.com/ Cc: Michael Roth <michael.roth(a)amd.com> Cc: Alexey Kardashevskiy <aik(a)amd.com> Cc: Pasha Tatashin <pasha.tatashin(a)soleen.com> Cc: James Gowans <jgowans(a)amazon.com> Signed-off-by: Jason Gunthorpe <jgg(a)nvidia.com> Alejandro Jimenez (1): iommu/amd: Use the generic iommu page table Jason Gunthorpe (14): genpt: Generic Page Table base API genpt: Add Documentation/ files iommupt: Add the basic structure of the iommu implementation iommupt: Add the AMD IOMMU v1 page table format iommupt: Add iova_to_phys op iommupt: Add unmap_pages op iommupt: Add map_pages op iommupt: Add read_and_clear_dirty op iommupt: Add a kunit test for Generic Page Table iommupt: Add a mock pagetable format for iommufd selftest to use iommufd: Change the selftest to use iommupt instead of xarray iommupt: Add the x86 64 bit page table format iommu/amd: Remove AMD io_pgtable support iommupt: Add a kunit test for the IOMMU implementation .clang-format | 1 + Documentation/driver-api/generic_pt.rst | 142 ++ Documentation/driver-api/index.rst | 1 + drivers/iommu/Kconfig | 2 + drivers/iommu/Makefile | 1 + drivers/iommu/amd/Kconfig | 5 +- drivers/iommu/amd/Makefile | 2 +- drivers/iommu/amd/amd_iommu.h | 1 - drivers/iommu/amd/amd_iommu_types.h | 110 +- drivers/iommu/amd/io_pgtable.c | 577 -------- drivers/iommu/amd/io_pgtable_v2.c | 370 ------ drivers/iommu/amd/iommu.c | 538 ++++---- drivers/iommu/generic_pt/.kunitconfig | 13 + drivers/iommu/generic_pt/Kconfig | 68 + drivers/iommu/generic_pt/fmt/Makefile | 26 + drivers/iommu/generic_pt/fmt/amdv1.h | 411 ++++++ drivers/iommu/generic_pt/fmt/defs_amdv1.h | 21 + drivers/iommu/generic_pt/fmt/defs_x86_64.h | 21 + drivers/iommu/generic_pt/fmt/iommu_amdv1.c | 15 + drivers/iommu/generic_pt/fmt/iommu_mock.c | 10 + drivers/iommu/generic_pt/fmt/iommu_template.h | 48 + drivers/iommu/generic_pt/fmt/iommu_x86_64.c | 11 + drivers/iommu/generic_pt/fmt/x86_64.h | 255 ++++ drivers/iommu/generic_pt/iommu_pt.h | 1162 +++++++++++++++++ drivers/iommu/generic_pt/kunit_generic_pt.h | 713 ++++++++++ drivers/iommu/generic_pt/kunit_iommu.h | 183 +++ drivers/iommu/generic_pt/kunit_iommu_pt.h | 487 +++++++ drivers/iommu/generic_pt/pt_common.h | 358 +++++ drivers/iommu/generic_pt/pt_defs.h | 329 +++++ drivers/iommu/generic_pt/pt_fmt_defaults.h | 233 ++++ drivers/iommu/generic_pt/pt_iter.h | 636 +++++++++ drivers/iommu/generic_pt/pt_log2.h | 122 ++ drivers/iommu/io-pgtable.c | 4 - drivers/iommu/iommufd/Kconfig | 1 + drivers/iommu/iommufd/iommufd_test.h | 11 +- drivers/iommu/iommufd/selftest.c | 438 +++---- include/linux/generic_pt/common.h | 167 +++ include/linux/generic_pt/iommu.h | 271 ++++ include/linux/io-pgtable.h | 2 - include/linux/irqchip/riscv-imsic.h | 3 +- tools/testing/selftests/iommu/iommufd.c | 60 +- tools/testing/selftests/iommu/iommufd_utils.h | 12 + 42 files changed, 6229 insertions(+), 1612 deletions(-) create mode 100644 Documentation/driver-api/generic_pt.rst delete mode 100644 drivers/iommu/amd/io_pgtable.c delete mode 100644 drivers/iommu/amd/io_pgtable_v2.c create mode 100644 drivers/iommu/generic_pt/.kunitconfig create mode 100644 drivers/iommu/generic_pt/Kconfig create mode 100644 drivers/iommu/generic_pt/fmt/Makefile create mode 100644 drivers/iommu/generic_pt/fmt/amdv1.h create mode 100644 drivers/iommu/generic_pt/fmt/defs_amdv1.h create mode 100644 drivers/iommu/generic_pt/fmt/defs_x86_64.h create mode 100644 drivers/iommu/generic_pt/fmt/iommu_amdv1.c create mode 100644 drivers/iommu/generic_pt/fmt/iommu_mock.c create mode 100644 drivers/iommu/generic_pt/fmt/iommu_template.h create mode 100644 drivers/iommu/generic_pt/fmt/iommu_x86_64.c create mode 100644 drivers/iommu/generic_pt/fmt/x86_64.h create mode 100644 drivers/iommu/generic_pt/iommu_pt.h create mode 100644 drivers/iommu/generic_pt/kunit_generic_pt.h create mode 100644 drivers/iommu/generic_pt/kunit_iommu.h create mode 100644 drivers/iommu/generic_pt/kunit_iommu_pt.h create mode 100644 drivers/iommu/generic_pt/pt_common.h create mode 100644 drivers/iommu/generic_pt/pt_defs.h create mode 100644 drivers/iommu/generic_pt/pt_fmt_defaults.h create mode 100644 drivers/iommu/generic_pt/pt_iter.h create mode 100644 drivers/iommu/generic_pt/pt_log2.h create mode 100644 include/linux/generic_pt/common.h create mode 100644 include/linux/generic_pt/iommu.h base-commit: 8440410283bb5533b676574211f31f030a18011b -- 2.43.0

3 weeks, 4 days

8
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[PATCH] selftests/ftrace: Add test dependency

by Thibault Ferrante

test_duplicates miss a running dependency and leads to test failures on kernel with specific configuration. Signed-off-by: Thibault Ferrante <thibault.ferrante(a)canonical.com> --- .../testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc b/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc index d3a79da215c8..0b5e4543e70b 100644 --- a/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc +++ b/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc @@ -1,7 +1,7 @@ #!/bin/sh # SPDX-License-Identifier: GPL-2.0 # description: Generic dynamic event - check if duplicate events are caught -# requires: dynamic_events "e[:[<group>/][<event>]] <attached-group>.<attached-event> [<args>]":README +# requires: dynamic_events events/syscalls/sys_enter_openat "e[:[<group>/][<event>]] <attached-group>.<attached-event> [<args>]":README echo 0 > events/enable -- 2.39.2

3 weeks, 4 days

2
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[PATCH v23 0/8] fork: Support shadow stacks in clone3()

by Mark Brown

At this point I think everyone in the on the kernel side is happy with this but there were some questions from the glibc side about the value of controlling the shadow stack placement and size, especially with the current inability to reuse the shadow stack for an exited thread. With support for reuse it would be possible to have a cache of shadow stacks as is currently supported for the normal stack. Since the discussion petered out I'm resending this in order to give people something work with while prototyping. It should be possible to prototype any potential kernel features to help build out shadow stack support in userspace by enabling shadow stack writes, as suggested by Rick Edgecombe this may end up being required anyway for supporting more exotic scenarios. On all current architectures with the feature writes to shadow stack require specific instructions so there are still security benefits even with writes enabled. I did send a change implementing a feature writing a token on thread exit to allow reuse: https://lore.kernel.org/r/20250921-arm64-gcs-exit-token-v1-0-45cf64e648d5@k… but wasn't planning to refresh it without some indication from the userspace side that that'd be useful. Non-process cover letter: The kernel has added support for shadow stacks, currently x86 only using their CET feature but both arm64 and RISC-V have equivalent features (GCS and Zicfiss respectively), I am actively working on GCS[1]. With shadow stacks the hardware maintains an additional stack containing only the return addresses for branch instructions which is not generally writeable by userspace and ensures that any returns are to the recorded addresses. This provides some protection against ROP attacks and making it easier to collect call stacks. These shadow stacks are allocated in the address space of the userspace process. Our API for shadow stacks does not currently offer userspace any flexiblity for managing the allocation of shadow stacks for newly created threads, instead the kernel allocates a new shadow stack with the same size as the normal stack whenever a thread is created with the feature enabled. The stacks allocated in this way are freed by the kernel when the thread exits or shadow stacks are disabled for the thread. This lack of flexibility and control isn't ideal, in the vast majority of cases the shadow stack will be over allocated and the implicit allocation and deallocation is not consistent with other interfaces. As far as I can tell the interface is done in this manner mainly because the shadow stack patches were in development since before clone3() was implemented. Since clone3() is readily extensible let's add support for specifying a shadow stack when creating a new thread or process, keeping the current implicit allocation behaviour if one is not specified either with clone3() or through the use of clone(). The user must provide a shadow stack pointer, this must point to memory mapped for use as a shadow stackby map_shadow_stack() with an architecture specified shadow stack token at the top of the stack. Yuri Khrustalev has raised questions from the libc side regarding discoverability of extended clone3() structure sizes[2], this seems like a general issue with clone3(). There was a suggestion to add a hwcap on arm64 which isn't ideal but is doable there, though architecture specific mechanisms would also be needed for x86 (and RISC-V if it's support gets merged before this does). The idea has, however, had strong pushback from the architecture maintainers and it is possible to detect support for this in clone3() by attempting a call with a misaligned shadow stack pointer specified so no hwcap has been added. [1] https://lore.kernel.org/linux-arm-kernel/20241001-arm64-gcs-v13-0-222b78d87… [2] https://lore.kernel.org/r/aCs65ccRQtJBnZ_5@arm.com Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v23: - Rebase onto v6.19-rc1. - Link to v22: https://lore.kernel.org/r/20251015-clone3-shadow-stack-v22-0-a8c8da011427@k… Changes in v22: - Rebase onto v6.18-rc1. - Cover letter updates. - Link to v21: https://lore.kernel.org/r/20250916-clone3-shadow-stack-v21-0-910493527013@k… Changes in v21: - Rebase onto https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git kernel-6.18.clone3 - Rename shadow_stack_token to shstk_token, since it's a simple rename I've kept the acks and reviews but I dropped the tested-bys just to be safe. - Link to v20: https://lore.kernel.org/r/20250902-clone3-shadow-stack-v20-0-4d9fff1c53e7@k… Changes in v20: - Comment fixes and clarifications in x86 arch_shstk_validate_clone() from Rick Edgecombe. - Spelling fix in documentation. - Link to v19: https://lore.kernel.org/r/20250819-clone3-shadow-stack-v19-0-bc957075479b@k… Changes in v19: - Rebase onto v6.17-rc1. - Link to v18: https://lore.kernel.org/r/20250702-clone3-shadow-stack-v18-0-7965d2b694db@k… Changes in v18: - Rebase onto v6.16-rc3. - Thanks to pointers from Yuri Khrustalev this version has been tested on x86 so I have removed the RFT tag. - Clarify clone3_shadow_stack_valid() comment about the Kconfig check. - Remove redundant GCSB DSYNCs in arm64 code. - Fix token validation on x86. - Link to v17: https://lore.kernel.org/r/20250609-clone3-shadow-stack-v17-0-8840ed97ff6f@k… Changes in v17: - Rebase onto v6.16-rc1. - Link to v16: https://lore.kernel.org/r/20250416-clone3-shadow-stack-v16-0-2ffc9ca3917b@k… Changes in v16: - Rebase onto v6.15-rc2. - Roll in fixes from x86 testing from Rick Edgecombe. - Rework so that the argument is shadow_stack_token. - Link to v15: https://lore.kernel.org/r/20250408-clone3-shadow-stack-v15-0-3fa245c6e3be@k… Changes in v15: - Rebase onto v6.15-rc1. - Link to v14: https://lore.kernel.org/r/20250206-clone3-shadow-stack-v14-0-805b53af73b9@k… Changes in v14: - Rebase onto v6.14-rc1. - Link to v13: https://lore.kernel.org/r/20241203-clone3-shadow-stack-v13-0-93b89a81a5ed@k… Changes in v13: - Rebase onto v6.13-rc1. - Link to v12: https://lore.kernel.org/r/20241031-clone3-shadow-stack-v12-0-7183eb8bee17@k… Changes in v12: - Add the regular prctl() to the userspace API document since arm64 support is queued in -next. - Link to v11: https://lore.kernel.org/r/20241005-clone3-shadow-stack-v11-0-2a6a2bd6d651@k… Changes in v11: - Rebase onto arm64 for-next/gcs, which is based on v6.12-rc1, and integrate arm64 support. - Rework the interface to specify a shadow stack pointer rather than a base and size like we do for the regular stack. - Link to v10: https://lore.kernel.org/r/20240821-clone3-shadow-stack-v10-0-06e8797b9445@k… Changes in v10: - Integrate fixes & improvements for the x86 implementation from Rick Edgecombe. - Require that the shadow stack be VM_WRITE. - Require that the shadow stack base and size be sizeof(void *) aligned. - Clean up trailing newline. - Link to v9: https://lore.kernel.org/r/20240819-clone3-shadow-stack-v9-0-962d74f99464@ke… Changes in v9: - Pull token validation earlier and report problems with an error return to parent rather than signal delivery to the child. - Verify that the top of the supplied shadow stack is VM_SHADOW_STACK. - Rework token validation to only do the page mapping once. - Drop no longer needed support for testing for signals in selftest. - Fix typo in comments. - Link to v8: https://lore.kernel.org/r/20240808-clone3-shadow-stack-v8-0-0acf37caf14c@ke… Changes in v8: - Fix token verification with user specified shadow stack. - Don't track user managed shadow stacks for child processes. - Link to v7: https://lore.kernel.org/r/20240731-clone3-shadow-stack-v7-0-a9532eebfb1d@ke… Changes in v7: - Rebase onto v6.11-rc1. - Typo fixes. - Link to v6: https://lore.kernel.org/r/20240623-clone3-shadow-stack-v6-0-9ee7783b1fb9@ke… Changes in v6: - Rebase onto v6.10-rc3. - Ensure we don't try to free the parent shadow stack in error paths of x86 arch code. - Spelling fixes in userspace API document. - Additional cleanups and improvements to the clone3() tests to support the shadow stack tests. - Link to v5: https://lore.kernel.org/r/20240203-clone3-shadow-stack-v5-0-322c69598e4b@ke… Changes in v5: - Rebase onto v6.8-rc2. - Rework ABI to have the user allocate the shadow stack memory with map_shadow_stack() and a token. - Force inlining of the x86 shadow stack enablement. - Move shadow stack enablement out into a shared header for reuse by other tests. - Link to v4: https://lore.kernel.org/r/20231128-clone3-shadow-stack-v4-0-8b28ffe4f676@ke… Changes in v4: - Formatting changes. - Use a define for minimum shadow stack size and move some basic validation to fork.c. - Link to v3: https://lore.kernel.org/r/20231120-clone3-shadow-stack-v3-0-a7b8ed3e2acc@ke… Changes in v3: - Rebase onto v6.7-rc2. - Remove stale shadow_stack in internal kargs. - If a shadow stack is specified unconditionally use it regardless of CLONE_ parameters. - Force enable shadow stacks in the selftest. - Update changelogs for RISC-V feature rename. - Link to v2: https://lore.kernel.org/r/20231114-clone3-shadow-stack-v2-0-b613f8681155@ke… Changes in v2: - Rebase onto v6.7-rc1. - Remove ability to provide preallocated shadow stack, just specify the desired size. - Link to v1: https://lore.kernel.org/r/20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@ke… --- Mark Brown (8): arm64/gcs: Return a success value from gcs_alloc_thread_stack() Documentation: userspace-api: Add shadow stack API documentation selftests: Provide helper header for shadow stack testing fork: Add shadow stack support to clone3() selftests/clone3: Remove redundant flushes of output streams selftests/clone3: Factor more of main loop into test_clone3() selftests/clone3: Allow tests to flag if -E2BIG is a valid error code selftests/clone3: Test shadow stack support Documentation/userspace-api/index.rst | 1 + Documentation/userspace-api/shadow_stack.rst | 44 +++++ arch/arm64/include/asm/gcs.h | 8 +- arch/arm64/kernel/process.c | 8 +- arch/arm64/mm/gcs.c | 55 +++++- arch/x86/include/asm/shstk.h | 11 +- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 53 ++++- include/asm-generic/cacheflush.h | 11 ++ include/linux/sched/task.h | 17 ++ include/uapi/linux/sched.h | 9 +- kernel/fork.c | 93 +++++++-- tools/testing/selftests/clone3/clone3.c | 226 ++++++++++++++++++---- tools/testing/selftests/clone3/clone3_selftests.h | 65 ++++++- tools/testing/selftests/ksft_shstk.h | 98 ++++++++++ 15 files changed, 620 insertions(+), 81 deletions(-) --- base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 change-id: 20231019-clone3-shadow-stack-15d40d2bf536 Best regards, -- Mark Brown <broonie(a)kernel.org>

3 weeks, 5 days

2
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[PATCH v2] selftests/filesystems: Assume that TIOCGPTPEER is defined

by Mark Brown

The devpts_pts selftest has an ifdef in case an architecture does not define TIOCGPTPEER, but the handling for this is broken since we need errno to be set to EINVAL in order to skip the test as we should. Given that this ioctl() has been defined since v4.15 we may as well just assume it's there rather than write handling code which will probably never get used. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v2: - Rebase onto v6.19-rc1. - Link to v1: https://patch.msgid.link/20251126-selftests-filesystems-devpts-tiocgptpeer-… --- tools/testing/selftests/filesystems/devpts_pts.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/tools/testing/selftests/filesystems/devpts_pts.c b/tools/testing/selftests/filesystems/devpts_pts.c index 54fea349204e..950e8b7f675b 100644 --- a/tools/testing/selftests/filesystems/devpts_pts.c +++ b/tools/testing/selftests/filesystems/devpts_pts.c @@ -100,7 +100,7 @@ static int resolve_procfd_symlink(int fd, char *buf, size_t buflen) static int do_tiocgptpeer(char *ptmx, char *expected_procfd_contents) { int ret; - int master = -1, slave = -1, fret = -1; + int master = -1, slave, fret = -1; master = open(ptmx, O_RDWR | O_NOCTTY | O_CLOEXEC); if (master < 0) { @@ -119,9 +119,7 @@ static int do_tiocgptpeer(char *ptmx, char *expected_procfd_contents) goto do_cleanup; } -#ifdef TIOCGPTPEER slave = ioctl(master, TIOCGPTPEER, O_RDWR | O_NOCTTY | O_CLOEXEC); -#endif if (slave < 0) { if (errno == EINVAL) { fprintf(stderr, "TIOCGPTPEER is not supported. " --- base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 change-id: 20251126-selftests-filesystems-devpts-tiocgptpeer-fbd30e579859 Best regards, -- Mark Brown <broonie(a)kernel.org>

3 weeks, 5 days

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[PATCH v2 0/9] KVM: x86: Improve the handling of debug exceptions during instruction emulation

by Hou Wenlong

During my testing, I found that guest debugging with 'DR6.BD' does not work in instruction emulation, as the current code only considers the guest's DR7. Upon reviewing the code, I also observed that the checks for the userspace guest debugging feature and the guest's own debugging feature are repeated in different places during instruction emulation, but the overall logic is the same. If guest debug is enabled, it needs to exit to userspace; otherwise, a #DB exception needs to be injected into the guest. Therefore, as suggested by Jiangshan Lai, some cleanup has been done for #DB handling in instruction emulation in this patchset. A new function named 'kvm_inject_emulated_db()' is introduced to consolidate all the checking logic. Moreover, I hope we can make the #DB interception path use the same function as well. Additionally, when I looked into the single-step #DB handling in instruction emulation, I noticed that the interrupt shadow is toggled, but it is not considered in the single-step #DB injection. This oversight causes VM entry to fail on VMX (due to pending debug exceptions state checking). As pointed out by Sean, fault-like code #DBs can be coincident with trap-like single-step #DBs at the instruction boundary on the hardware. However it is difficult to emulate this in the emulator, as kvm_vcpu_check_code_breakpoint() is called at the start of the next instruction while the single-step #DB for the previous instruction has already been injected. v1->v2: - cleanup in inject_emulated_exception(). - rename 'set_pending_dbg' callback as 'refresh_pending_dbg_exceptions'. - fold refresh_pending_dbg_exceptions() call into kvm_vcpu_do_singlestep(). - Split the change to move up kvm_set_rflags() into a single patch. - Move the #DB and IRQ handler registration after guest debug testcases. Hou Wenlong (9): KVM: x86: Capture "struct x86_exception" in inject_emulated_exception() KVM: x86: Set guest DR6 by kvm_queue_exception_p() in instruction emulation KVM: x86: Check guest debug in DR access instruction emulation KVM: x86: Only check effective code breakpoint in emulation KVM: x86: Consolidate KVM_GUESTDBG_SINGLESTEP check into the kvm_inject_emulated_db() KVM: x86: Move kvm_set_rflags() up before kvm_vcpu_do_singlestep() KVM: VMX: Refresh 'PENDING_DBG_EXCEPTIONS.BS' bit during instruction emulation KVM: selftests: Verify guest debug DR7.GD checking during instruction emulation KVM: selftests: Verify 'BS' bit checking in pending debug exception during VM entry arch/x86/include/asm/kvm-x86-ops.h | 1 + arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/emulate.c | 14 +-- arch/x86/kvm/kvm_emulate.h | 7 +- arch/x86/kvm/vmx/main.c | 9 ++ arch/x86/kvm/vmx/vmx.c | 15 ++- arch/x86/kvm/vmx/x86_ops.h | 1 + arch/x86/kvm/x86.c | 116 ++++++++++-------- arch/x86/kvm/x86.h | 7 ++ .../selftests/kvm/include/x86/processor.h | 3 +- tools/testing/selftests/kvm/x86/debug_regs.c | 72 ++++++++++- 11 files changed, 178 insertions(+), 68 deletions(-) base-commit: 5d3e2d9ba9ed68576c70c127e4f7446d896f2af2 -- 2.31.1

3 weeks, 5 days

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[PATCH 0/7] KVM: x86: Improve the handling of debug exceptions during instruction emulation

by Hou Wenlong

During my testing, I found that guest debugging with 'DR6.BD' does not work in instruction emulation, as the current code only considers the guest's DR7. Upon reviewing the code, I also observed that the checks for the userspace guest debugging feature and the guest's own debugging feature are repeated in different places during instruction emulation, but the overall logic is the same. If guest debugging is enabled, it needs to exit to userspace; otherwise, a #DB exception needs to be injected into the guest. Therefore, as suggested by Jiangshan Lai, some cleanup has been done for #DB handling in instruction emulation in this patchset. A new function named 'kvm_inject_emulated_db()' is introduced to consolidate all the checking logic. Moreover, I hope we can make the #DB interception path use the same function as well. Additionally, when I looked into the single-step #DB handling in instruction emulation, I noticed that the interrupt shadow is toggled, but it is not considered in the single-step #DB injection. This oversight causes VM entry to fail on VMX (due to pending debug exceptions checking) or breaks the 'MOV SS' suppressed #DB. For the latter, I have kept the behavior for now in my patchset, as I need some suggestions. Hou Wenlong (7): KVM: x86: Set guest DR6 by kvm_queue_exception_p() in instruction emulation KVM: x86: Check guest debug in DR access instruction emulation KVM: x86: Only check effective code breakpoint in emulation KVM: x86: Consolidate KVM_GUESTDBG_SINGLESTEP check into the kvm_inject_emulated_db() KVM: VMX: Set 'BS' bit in pending debug exceptions during instruction emulation KVM: selftests: Verify guest debug DR7.GD checking during instruction emulation KVM: selftests: Verify 'BS' bit checking in pending debug exception during VM entry arch/x86/include/asm/kvm-x86-ops.h | 1 + arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/emulate.c | 14 +-- arch/x86/kvm/kvm_emulate.h | 7 +- arch/x86/kvm/vmx/main.c | 9 ++ arch/x86/kvm/vmx/vmx.c | 14 ++- arch/x86/kvm/vmx/x86_ops.h | 1 + arch/x86/kvm/x86.c | 109 +++++++++++------- arch/x86/kvm/x86.h | 7 ++ .../selftests/kvm/include/x86/processor.h | 3 +- tools/testing/selftests/kvm/x86/debug_regs.c | 64 +++++++++- 11 files changed, 167 insertions(+), 63 deletions(-) base-commit: ecbcc2461839e848970468b44db32282e5059925 -- 2.31.1

3 weeks, 5 days

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[PATCH v3 0/3] selftests/filelock: Make output more kselftestish

by Mark Brown

This series makes the output from the ofdlocks test a bit easier for tooling to work with, and also ignores the generated file while we're here. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v3: - Rebase onto v6.19-rc1. - Link to v2: https://lore.kernel.org/r/20251015-selftest-filelock-ktap-v2-0-f5fd21b75c3a… Changes in v2: - Rebase onto v6.18-rc1. - Link to v1: https://lore.kernel.org/r/20250818-selftest-filelock-ktap-v1-0-d41af77f1396… --- Mark Brown (3): kselftest/filelock: Use ksft_perror() kselftest/filelock: Report each test in oftlocks separately kselftest/filelock: Add a .gitignore file tools/testing/selftests/filelock/.gitignore | 1 + tools/testing/selftests/filelock/ofdlocks.c | 94 +++++++++++++---------------- 2 files changed, 42 insertions(+), 53 deletions(-) --- base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 change-id: 20250604-selftest-filelock-ktap-f2ae998a0de0 Best regards, -- Mark Brown <broonie(a)kernel.org>

3 weeks, 5 days

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Issue in parsing of tests that use KUNIT_CASE_PARAM

by Ojaswin Mujoo

Hello, While writing some Kunit tests for ext4 filesystem, I'm encountering an issue in the way we display the diagnostic logs upon failures, when using KUNIT_CASE_PARAM() to write the tests. This can be observed by patching fs/ext4/mballoc-test.c to fail and print one of the params: --- a/fs/ext4/mballoc-test.c +++ b/fs/ext4/mballoc-test.c @@ -350,6 +350,8 @@ static int mbt_kunit_init(struct kunit *test) struct super_block *sb; int ret; + KUNIT_FAIL(test, "Failed: blocksize_bits=%d", layout->blocksize_bits); + sb = mbt_ext4_alloc_super_block(); if (sb == NULL) return -ENOMEM; With the above change, we can observe the following output (snipped): [18:50:25] ============== ext4_mballoc_test (7 subtests) ============== [18:50:25] ================= test_new_blocks_simple ================== [18:50:25] [FAILED] block_bits=10 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 [18:50:25] # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 [18:50:25] Failed: blocksize_bits=12 [18:50:25] [FAILED] block_bits=12 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 [18:50:25] # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 [18:50:25] Failed: blocksize_bits=16 [18:50:25] [FAILED] block_bits=16 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 [18:50:25] # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 [18:50:25] Failed: blocksize_bits=10 [18:50:25] # test_new_blocks_simple: pass:0 fail:3 skip:0 total:3 [18:50:25] ============= [FAILED] test_new_blocks_simple ============== <snip> Note that the diagnostic logs don't show up correctly. Ideally they should be before test result but here the first [FAILED] test has no logs printed above whereas the last "Failed: blocksize_bits=10" print comes after the last subtest, when it actually corresponds to the first subtest. The KTAP file itself seems to have diagnostic logs in the right place: KTAP version 1 1..2 KTAP version 1 # Subtest: ext4_mballoc_test # module: ext4 1..7 KTAP version 1 # Subtest: test_new_blocks_simple # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 Failed: blocksize_bits=10 not ok 1 block_bits=10 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 Failed: blocksize_bits=12 not ok 2 block_bits=12 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 # test_new_blocks_simple: EXPECTATION FAILED at fs/ext4/mballoc-test.c:364 Failed: blocksize_bits=16 not ok 3 block_bits=16 cluster_bits=3 blocks_per_group=8192 group_count=4 desc_size=64 # test_new_blocks_simple: pass:0 fail:3 skip:0 total:3 not ok 1 test_new_blocks_simple <snip> By tracing kunit_parser.py script, I could see the issue here is in the parsing of the "Subtest: test_new_blocks_simple". We end up associating everything below the subtest till "not ok 1 block_bits=10..." as diagnostic logs of the subtest, while these lons actually belong to the first of the 3 subtests under this test. I tired to figure out a way to fix the parsing but fixing one thing broke something else. Im starting to think that the issue is that there are 3 subtests under test_new_block_simple (array of 3 params passed to KUNIT_CASE_PARAM), but instead of creating 3 structured subtests, the KTAP output dumps the results of all 3 directly under subtest:test_new_blocks_simple. Which makes it tricky to determine where the diagnostic log/attributes of test_new_blocks_simple ends and that of its children begins. I'm not very familiar with KUnit framework so I though I'd reach out here for some pointers. I can dedicate some time fixing this but I'd like to know if this is something we need to somehow fix in parsing or during generation of the KTAP file itself? Any pointers would be appreciated. Thanks, Ojaswin

3 weeks, 5 days

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[PATCH][v2] watchdog: softlockup: panic when lockup duration exceeds N thresholds

by lirongqing

From: Li RongQing <lirongqing(a)baidu.com> The softlockup_panic sysctl is currently a binary option: panic immediately or never panic on soft lockups. Panicking on any soft lockup, regardless of duration, can be overly aggressive for brief stalls that may be caused by legitimate operations. Conversely, never panicking may allow severe system hangs to persist undetected. Extend softlockup_panic to accept an integer threshold, allowing the kernel to panic only when the normalized lockup duration exceeds N watchdog threshold periods. This provides finer-grained control to distinguish between transient delays and persistent system failures. The accepted values are: - 0: Don't panic (unchanged) - 1: Panic when duration >= 1 * threshold (20s default, original behavior) - N > 1: Panic when duration >= N * threshold (e.g., 2 = 40s, 3 = 60s.) The original behavior is preserved for values 0 and 1, maintaining full backward compatibility while allowing systems to tolerate brief lockups while still catching severe, persistent hangs. Signed-off-by: Li RongQing <lirongqing(a)baidu.com> Cc: Eduard Zingerman <eddyz87(a)gmail.com> Cc: Hao Luo <haoluo(a)google.com> Cc: Jiri Olsa <jolsa(a)kernel.org> Cc: John Fastabend <john.fastabend(a)gmail.com> Cc: KP Singh <kpsingh(a)kernel.org> Cc: Lance Yang <lance.yang(a)linux.dev> Cc: Martin KaFai Lau <martin.lau(a)linux.dev> Cc: Nicholas Piggin <npiggin(a)gmail.com> Cc: Song Liu <song(a)kernel.org> Cc: Stanislav Fomichev <sdf(a)fomichev.me> Cc: Yonghong Song <yonghong.song(a)linux.dev> Cc: Andrew Morton <akpm(a)linux-foundation.org> --- Diff with v1: add a temp variable thresh_count chang config to 0 in kernel/configs/debug.config Documentation/admin-guide/kernel-parameters.txt | 10 +++++----- arch/arm/configs/aspeed_g5_defconfig | 2 +- arch/arm/configs/pxa3xx_defconfig | 2 +- arch/openrisc/configs/or1klitex_defconfig | 2 +- arch/powerpc/configs/skiroot_defconfig | 2 +- drivers/gpu/drm/ci/arm.config | 2 +- drivers/gpu/drm/ci/arm64.config | 2 +- drivers/gpu/drm/ci/x86_64.config | 2 +- kernel/configs/debug.config | 2 +- kernel/watchdog.c | 10 ++++++---- lib/Kconfig.debug | 13 +++++++------ tools/testing/selftests/bpf/config | 2 +- tools/testing/selftests/wireguard/qemu/kernel.config | 2 +- 13 files changed, 28 insertions(+), 25 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a8d0afd..27c5f96 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6934,12 +6934,12 @@ Kernel parameters softlockup_panic= [KNL] Should the soft-lockup detector generate panics. - Format: 0 | 1 + Format: <int> - A value of 1 instructs the soft-lockup detector - to panic the machine when a soft-lockup occurs. It is - also controlled by the kernel.softlockup_panic sysctl - and CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, which is the + A value of non-zero instructs the soft-lockup detector + to panic the machine when a soft-lockup duration exceeds + N thresholds. It is also controlled by the kernel.softlockup_panic + sysctl and CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, which is the respective build-time switch to that functionality. softlockup_all_cpu_backtrace= diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig index 2e6ea13..ec558e5 100644 --- a/arch/arm/configs/aspeed_g5_defconfig +++ b/arch/arm/configs/aspeed_g5_defconfig @@ -306,7 +306,7 @@ CONFIG_SCHED_STACK_END_CHECK=y CONFIG_PANIC_ON_OOPS=y CONFIG_PANIC_TIMEOUT=-1 CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1 CONFIG_WQ_WATCHDOG=y # CONFIG_SCHED_DEBUG is not set diff --git a/arch/arm/configs/pxa3xx_defconfig b/arch/arm/configs/pxa3xx_defconfig index 07d422f..fb272e3 100644 --- a/arch/arm/configs/pxa3xx_defconfig +++ b/arch/arm/configs/pxa3xx_defconfig @@ -100,7 +100,7 @@ CONFIG_PRINTK_TIME=y CONFIG_DEBUG_KERNEL=y CONFIG_MAGIC_SYSRQ=y CONFIG_DEBUG_SHIRQ=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 # CONFIG_SCHED_DEBUG is not set CONFIG_DEBUG_SPINLOCK=y CONFIG_DEBUG_SPINLOCK_SLEEP=y diff --git a/arch/openrisc/configs/or1klitex_defconfig b/arch/openrisc/configs/or1klitex_defconfig index fb1eb9a..984b0e3 100644 --- a/arch/openrisc/configs/or1klitex_defconfig +++ b/arch/openrisc/configs/or1klitex_defconfig @@ -52,5 +52,5 @@ CONFIG_LSM="lockdown,yama,loadpin,safesetid,integrity,bpf" CONFIG_PRINTK_TIME=y CONFIG_PANIC_ON_OOPS=y CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BUG_ON_DATA_CORRUPTION=y diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig index 2b71a6d..a4114fc 100644 --- a/arch/powerpc/configs/skiroot_defconfig +++ b/arch/powerpc/configs/skiroot_defconfig @@ -289,7 +289,7 @@ CONFIG_SCHED_STACK_END_CHECK=y CONFIG_DEBUG_STACKOVERFLOW=y CONFIG_PANIC_ON_OOPS=y CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_HARDLOCKUP_DETECTOR=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y CONFIG_WQ_WATCHDOG=y diff --git a/drivers/gpu/drm/ci/arm.config b/drivers/gpu/drm/ci/arm.config index 411e814..d7c5167 100644 --- a/drivers/gpu/drm/ci/arm.config +++ b/drivers/gpu/drm/ci/arm.config @@ -52,7 +52,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=n -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=n +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=0 CONFIG_FW_LOADER_COMPRESS=y diff --git a/drivers/gpu/drm/ci/arm64.config b/drivers/gpu/drm/ci/arm64.config index fddfbd4..ea0e307 100644 --- a/drivers/gpu/drm/ci/arm64.config +++ b/drivers/gpu/drm/ci/arm64.config @@ -161,7 +161,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_DETECT_HUNG_TASK=y diff --git a/drivers/gpu/drm/ci/x86_64.config b/drivers/gpu/drm/ci/x86_64.config index 8eaba388..7ac98a7 100644 --- a/drivers/gpu/drm/ci/x86_64.config +++ b/drivers/gpu/drm/ci/x86_64.config @@ -47,7 +47,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_DETECT_HUNG_TASK=y diff --git a/kernel/configs/debug.config b/kernel/configs/debug.config index 9f6ab7d..774702591 100644 --- a/kernel/configs/debug.config +++ b/kernel/configs/debug.config @@ -84,7 +84,7 @@ CONFIG_SLUB_DEBUG_ON=y # Debug Oops, Lockups and Hangs # CONFIG_BOOTPARAM_HUNG_TASK_PANIC=0 -# CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC is not set +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=0 CONFIG_DEBUG_ATOMIC_SLEEP=y CONFIG_DETECT_HUNG_TASK=y CONFIG_PANIC_ON_OOPS=y diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 0685e3a..8168e0d 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -363,7 +363,7 @@ static struct cpumask watchdog_allowed_mask __read_mostly; /* Global variables, exported for sysctl */ unsigned int __read_mostly softlockup_panic = - IS_ENABLED(CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC); + CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC; static bool softlockup_initialized __read_mostly; static u64 __read_mostly sample_period; @@ -774,8 +774,8 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) { unsigned long touch_ts, period_ts, now; struct pt_regs *regs = get_irq_regs(); - int duration; int softlockup_all_cpu_backtrace; + int duration, thresh_count; unsigned long flags; if (!watchdog_enabled) @@ -879,7 +879,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) add_taint(TAINT_SOFTLOCKUP, LOCKDEP_STILL_OK); sys_info(softlockup_si_mask & ~SYS_INFO_ALL_BT); - if (softlockup_panic) + thresh_count = duration / get_softlockup_thresh(); + + if (softlockup_panic && thresh_count >= softlockup_panic) panic("softlockup: hung tasks"); } @@ -1228,7 +1230,7 @@ static const struct ctl_table watchdog_sysctls[] = { .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .extra2 = SYSCTL_INT_MAX, }, { .procname = "softlockup_sys_info", diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index ba36939..17a7a77 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1110,13 +1110,14 @@ config SOFTLOCKUP_DETECTOR_INTR_STORM the CPU stats and the interrupt counts during the "soft lockups". config BOOTPARAM_SOFTLOCKUP_PANIC - bool "Panic (Reboot) On Soft Lockups" + int "Panic (Reboot) On Soft Lockups" depends on SOFTLOCKUP_DETECTOR + default 0 help - Say Y here to enable the kernel to panic on "soft lockups", - which are bugs that cause the kernel to loop in kernel - mode for more than 20 seconds (configurable using the watchdog_thresh - sysctl), without giving other tasks a chance to run. + Set to a non-zero value N to enable the kernel to panic on "soft + lockups", which are bugs that cause the kernel to loop in kernel + mode for more than (N * 20 seconds) (configurable using the + watchdog_thresh sysctl), without giving other tasks a chance to run. The panic can be used in combination with panic_timeout, to cause the system to reboot automatically after a @@ -1124,7 +1125,7 @@ config BOOTPARAM_SOFTLOCKUP_PANIC high-availability systems that have uptime guarantees and where a lockup must be resolved ASAP. - Say N if unsure. + Say 0 if unsure. config HAVE_HARDLOCKUP_DETECTOR_BUDDY bool diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 558839e..2485538 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -1,6 +1,6 @@ CONFIG_BLK_DEV_LOOP=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BPF=y CONFIG_BPF_EVENTS=y CONFIG_BPF_JIT=y diff --git a/tools/testing/selftests/wireguard/qemu/kernel.config b/tools/testing/selftests/wireguard/qemu/kernel.config index 0504c11..bb89d2d 100644 --- a/tools/testing/selftests/wireguard/qemu/kernel.config +++ b/tools/testing/selftests/wireguard/qemu/kernel.config @@ -80,7 +80,7 @@ CONFIG_HARDLOCKUP_DETECTOR=y CONFIG_WQ_WATCHDOG=y CONFIG_DETECT_HUNG_TASK=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1 CONFIG_PANIC_TIMEOUT=-1 CONFIG_STACKTRACE=y -- 2.9.4

3 weeks, 5 days

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[PATCHSET v11 sched_ext/for-6.20] Add a deadline server for sched_ext tasks

by Andrea Righi

sched_ext tasks can be starved by long-running RT tasks, especially since RT throttling was replaced by deadline servers to boost only SCHED_NORMAL tasks. Several users in the community have reported issues with RT stalling sched_ext tasks. This is fairly common on distributions or environments where applications like video compositors, audio services, etc. run as RT tasks by default. Example trace (showing a per-CPU kthread stalled due to the sway Wayland compositor running as an RT task): runnable task stall (kworker/0:0[106377] failed to run for 5.043s) ... CPU 0 : nr_run=3 flags=0xd cpu_rel=0 ops_qseq=20646200 pnt_seq=45388738 curr=sway[994] class=rt_sched_class R kworker/0:0[106377] -5043ms scx_state/flags=3/0x1 dsq_flags=0x0 ops_state/qseq=0/0 sticky/holding_cpu=-1/-1 dsq_id=0x8000000000000002 dsq_vtime=0 slice=20000000 cpus=01 This is often perceived as a bug in the BPF schedulers, but in reality they can't do much: RT tasks run outside their control and can potentially consume 100% of the CPU bandwidth. Fix this by adding a sched_ext deadline server, so that sched_ext tasks are also boosted and do not suffer starvation. Two kselftests are also provided to verify the starvation fixes and bandwidth allocation is correct. == Design == - The EXT server is initialized at boot time and remains configured throughout the system's lifetime - It starts automatically when the first sched_ext task is enqueued (rq->scx.nr_running == 1) - The server's pick function (ext_server_pick_task) always selects sched_ext tasks when active - Runtime accounting happens in update_curr_scx() during task execution and update_curr_idle() when idle - Bandwidth accounting includes both fair and ext servers in root domain calculations - A debugfs interface (/sys/kernel/debug/sched/ext_server/) allows runtime tuning of server parameters == Highlights in this version == As discussed at the sched_ext microconference at LPC Tokyo, the plan is to start with a simpler approach, avoiding automatically creating or tearing down the EXT server bandwidth reservation when a BPF scheduler is loaded or unloaded. Instead, the reservation is kept permanently active. This significantly simplifies the logic while still addressing the starvation issue. Any fine-tuning of the bandwidth reservation is delegated to the system administrator, who can adjust it via the debugfs interface. In the future, a more suitable interface can be introduced and automatic removal of the reservation when the BPF scheduler is unloaded can be revisited. This patchset is also available in the following git branch: git://git.kernel.org/pub/scm/linux/kernel/git/arighi/linux.git scx-dl-server Changes in v11: - do not create/remove the bandwidth reservation for the ext server when a BPF scheduler is loaded/unloaded, but keep the reservation bandwdith always active - change rt_stall kselftest to validate both FAIR and EXT DL servers - Link to v10: https://lore.kernel.org/all/20250903095008.162049-1-arighi@nvidia.com/ Changes in v10: - reordered patches to better isolate sched_ext changes vs sched/deadline changes (Andrea Righi) - define ext_server only with CONFIG_SCHED_CLASS_EXT=y (Andrea Righi) - add WARN_ON_ONCE(!cpus) check in dl_server_apply_params() (Andrea Righi) - wait for inactive_task_timer to fire before removing the bandwidth reservation (Juri Lelli) - remove explicit dl_server_stop() in dequeue_task_scx() to reduce timer reprogramming overhead (Juri Lelli) - do not restart pick_task() when invoked by the dl_server (Tejun Heo) - rename rq_dl_server to dl_server (Peter Zijlstra) - fixed a missing dl_server start in dl_server_on() (Christian Loehle) - add a comment to the rt_stall selftest to better explain the 4% threshold (Emil Tsalapatis) - Link to v9: https://lore.kernel.org/all/20251017093214.70029-1-arighi@nvidia.com/ Changes in v9: - Drop the ->balance() logic as its functionality is now integrated into ->pick_task(), allowing dl_server to call pick_task_scx() directly - Link to v8: https://lore.kernel.org/all/20250903095008.162049-1-arighi@nvidia.com/ Changes in v8: - Add tj's patch to de-couple balance and pick_task and avoid changing sched/core callbacks to propagate @rf - Simplify dl_se->dl_server check (suggested by PeterZ) - Small coding style fixes in the kselftests - Link to v7: https://lore.kernel.org/all/20250809184800.129831-1-joelagnelf@nvidia.com/ Changes in v7: - Rebased to Linus master - Link to v6: https://lore.kernel.org/all/20250702232944.3221001-1-joelagnelf@nvidia.com/ Changes in v6: - Added Acks to few patches - Fixes to few nits suggested by Tejun - Link to v5: https://lore.kernel.org/all/20250620203234.3349930-1-joelagnelf@nvidia.com/ Changes in v5: - Added a kselftest (total_bw) to sched_ext to verify bandwidth values from debugfs - Address comment from Andrea about redundant rq clock invalidation - Link to v4: https://lore.kernel.org/all/20250617200523.1261231-1-joelagnelf@nvidia.com/ Changes in v4: - Fixed issues with hotplugged CPUs having their DL server bandwidth altered due to loading SCX - Fixed other issues - Rebased on Linus master - All sched_ext kselftests reliably pass now, also verified that the total_bw in debugfs (CONFIG_SCHED_DEBUG) is conserved with these patches - Link to v3: https://lore.kernel.org/all/20250613051734.4023260-1-joelagnelf@nvidia.com/ Changes in v3: - Removed code duplication in debugfs. Made ext interface separate - Fixed issue where rq_lock_irqsave was not used in the relinquish patch - Fixed running bw accounting issue in dl_server_remove_params - Link to v2: https://lore.kernel.org/all/20250602180110.816225-1-joelagnelf@nvidia.com/ Changes in v2: - Fixed a hang related to using rq_lock instead of rq_lock_irqsave - Added support to remove BW of DL servers when they are switched to/from EXT - Link to v1: https://lore.kernel.org/all/20250315022158.2354454-1-joelagnelf@nvidia.com/ Andrea Righi (2): sched_ext: Add a DL server for sched_ext tasks selftests/sched_ext: Add test for sched_ext dl_server Joel Fernandes (5): sched/deadline: Clear the defer params sched/debug: Fix updating of ppos on server write ops sched/debug: Stop and start server based on if it was active sched/debug: Add support to change sched_ext server params selftests/sched_ext: Add test for DL server total_bw consistency kernel/sched/core.c | 6 + kernel/sched/deadline.c | 87 +++++-- kernel/sched/debug.c | 171 +++++++++++--- kernel/sched/ext.c | 42 ++++ kernel/sched/idle.c | 3 + kernel/sched/sched.h | 2 + kernel/sched/topology.c | 5 + tools/testing/selftests/sched_ext/Makefile | 2 + tools/testing/selftests/sched_ext/rt_stall.bpf.c | 23 ++ tools/testing/selftests/sched_ext/rt_stall.c | 240 +++++++++++++++++++ tools/testing/selftests/sched_ext/total_bw.c | 281 +++++++++++++++++++++++ 11 files changed, 811 insertions(+), 51 deletions(-) create mode 100644 tools/testing/selftests/sched_ext/rt_stall.bpf.c create mode 100644 tools/testing/selftests/sched_ext/rt_stall.c create mode 100644 tools/testing/selftests/sched_ext/total_bw.c

3 weeks, 5 days

2
11
0 0

[PATCH] kunit: fix up const mis-match in many assert functions

by Greg Kroah-Hartman

In many kunit assert functions a const pointer is passed to container_of() and out pops a non-const pointer, which really isn't the correct thing to do at all. Fix this up by correctly marking the casted-to pointer as const to preserve the marking. Cc: Brendan Higgins <brendan.higgins(a)linux.dev> Cc: David Gow <davidgow(a)google.com> Cc: Rae Moar <raemoar63(a)gmail.com> Cc: linux-kselftest(a)vger.kernel.org Cc: kunit-dev(a)googlegroups.com Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- lib/kunit/assert.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/lib/kunit/assert.c b/lib/kunit/assert.c index 867aa5c4bccf..4c751ad8506a 100644 --- a/lib/kunit/assert.c +++ b/lib/kunit/assert.c @@ -51,7 +51,7 @@ void kunit_unary_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_unary_assert *unary_assert; + const struct kunit_unary_assert *unary_assert; unary_assert = container_of(assert, struct kunit_unary_assert, assert); @@ -71,7 +71,7 @@ void kunit_ptr_not_err_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_ptr_not_err_assert *ptr_assert; + const struct kunit_ptr_not_err_assert *ptr_assert; ptr_assert = container_of(assert, struct kunit_ptr_not_err_assert, assert); @@ -117,7 +117,7 @@ void kunit_binary_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_binary_assert *binary_assert; + const struct kunit_binary_assert *binary_assert; binary_assert = container_of(assert, struct kunit_binary_assert, assert); @@ -145,7 +145,7 @@ void kunit_binary_ptr_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_binary_ptr_assert *binary_assert; + const struct kunit_binary_ptr_assert *binary_assert; binary_assert = container_of(assert, struct kunit_binary_ptr_assert, assert); @@ -185,7 +185,7 @@ void kunit_binary_str_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_binary_str_assert *binary_assert; + const struct kunit_binary_str_assert *binary_assert; binary_assert = container_of(assert, struct kunit_binary_str_assert, assert); @@ -237,7 +237,7 @@ void kunit_mem_assert_format(const struct kunit_assert *assert, const struct va_format *message, struct string_stream *stream) { - struct kunit_mem_assert *mem_assert; + const struct kunit_mem_assert *mem_assert; mem_assert = container_of(assert, struct kunit_mem_assert, assert); -- 2.52.0

3 weeks, 5 days

2
1
0 0

[PATCH v5 00/24] ARM64 PMU Partitioning

by Colton Lewis

This series creates a new PMU scheme on ARM, a partitioned PMU that allows reserving a subset of counters for more direct guest access, significantly reducing overhead. More details, including performance benchmarks, can be read in the v1 cover letter linked below. An overview of what this series accomplishes was presented at KVM Forum 2025. Slides [1] and video [2] are linked below. The long duration between v4 and v5 is due to time spent on this project being monopolized preparing this feature for internal production. As a result, there are too many improvements to fully list here, but I will cover the notable ones. v5: * Rebase onto v6.18-rc7. This required pulling some reorganization patches from Anish and Sean that were dependencies from previous versions based on kvm/queue but never made it to upstream. * Ensure FGTs (fine-grained traps) are correctly programmed at vCPU load using kvm_vcpu_load_fgt() and helpers introduced by Oliver Upton. * Cleanly separate concerns of whether the partitioned PMU is enabled for the guest and whether FGT should be enabled. This allows that the capability can be VM-scoped while the implementation detail of whether FGT and context switching are in effect can remain vCPU-scoped. * Shrink the uAPI change. Instead of a cap and corresponding ioctl, the feature can be controlled by just a cap with an argument. The cap is now also VM-scoped and enforces ordering that it should be decided before vCPUs are created. Whether the cap is enabled is now tracked by the new flag KVM_ARCH_ARM_PARTITIONED_PMU_ENABLED. * Improve log messages when partitioning in the PMUv3 driver. * Introduce a global variable armv8pmu_hpmn_max in the PMUv3 driver so KVM code can read if a value was set before the PMU is probed. This is needed to properly test if we have the capability before vCPUs are created. * Make it possible for a VMM to filter the HPMN0 feature bit. * Fix event filter problems with PMEVTYPER handling in writethrough_pmevtyper() and kvm_pmu_apply_event_filter() by using kvm_pmu_event_mask() in the right spots. And if an event is filtered, write the physical register with the appropriate exclude bits set but keep the virtual register exactly what the guest wrote. * Fix register access problems with the PMU register fast path handler by lifting some static PMU access checks from sys_regs.c to use them in the fast path too and make bit masking more strict for better ARM compliance. * Fix the readability and logic of programming the MDCR_EL2 register when entering the guest. Make sure to set the HPME bit to allow host counters to count guest events. Set TPM and TPMCR by default and clear them if partitioning is enabled rather than the previous inverted logic of leaving them clear and setting them if partitioning is not enabled. Make the HPMN field computation more clear. * As part of lazy context switching, do a load when the guest is switching to physical access to ensure any previous writes that only reached the virtual registers reach the physical ones as well and are not clobbered by the next vcpu_put(). * Other fixes and improvements that are too small to mention or left out from my personal notes. v4: https://lore.kernel.org/kvmarm/20250714225917.1396543-1-coltonlewis@google.… v3: https://lore.kernel.org/kvm/20250626200459.1153955-1-coltonlewis@google.com/ v2: https://lore.kernel.org/kvm/20250620221326.1261128-1-coltonlewis@google.com/ v1: https://lore.kernel.org/kvm/20250602192702.2125115-1-coltonlewis@google.com/ [1] https://gitlab.com/qemu-project/kvm-forum/-/raw/main/_attachments/2025/Opti… [2] https://www.youtube.com/watch?v=YRzZ8jMIA6M&list=PLW3ep1uCIRfxwmllXTOA2txfD… Anish Ghulati (1): KVM: arm64: Move arm_{psci,hypercalls}.h to an internal KVM path Colton Lewis (20): arm64: cpufeature: Add cpucap for HPMN0 KVM: arm64: Reorganize PMU functions perf: arm_pmuv3: Introduce method to partition the PMU perf: arm_pmuv3: Generalize counter bitmasks perf: arm_pmuv3: Keep out of guest counter partition KVM: arm64: Set up FGT for Partitioned PMU KVM: arm64: Writethrough trapped PMEVTYPER register KVM: arm64: Use physical PMSELR for PMXEVTYPER if partitioned KVM: arm64: Writethrough trapped PMOVS register KVM: arm64: Write fast path PMU register handlers KVM: arm64: Setup MDCR_EL2 to handle a partitioned PMU KVM: arm64: Account for partitioning in PMCR_EL0 access KVM: arm64: Context swap Partitioned PMU guest registers KVM: arm64: Enforce PMU event filter at vcpu_load() KVM: arm64: Implement lazy PMU context swaps perf: arm_pmuv3: Handle IRQs for Partitioned PMU guest counters KVM: arm64: Inject recorded guest interrupts KVM: arm64: Add KVM_CAP to partition the PMU KVM: selftests: Add find_bit to KVM library KVM: arm64: selftests: Add test case for partitioned PMU Marc Zyngier (1): KVM: arm64: Reorganize PMU includes Sean Christopherson (2): KVM: arm64: Include KVM headers to get forward declarations KVM: arm64: Move ARM specific headers in include/kvm to arch directory Documentation/virt/kvm/api.rst | 24 + arch/arm/include/asm/arm_pmuv3.h | 28 + arch/arm64/include/asm/arm_pmuv3.h | 61 +- .../arm64/include/asm/kvm_arch_timer.h | 2 + arch/arm64/include/asm/kvm_host.h | 24 +- .../arm64/include/asm/kvm_pmu.h | 142 ++++ arch/arm64/include/asm/kvm_types.h | 7 +- .../arm64/include/asm/kvm_vgic.h | 0 arch/arm64/kernel/cpufeature.c | 8 + arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/arch_timer.c | 5 +- arch/arm64/kvm/arm.c | 23 +- {include => arch/arm64}/kvm/arm_hypercalls.h | 0 {include => arch/arm64}/kvm/arm_psci.h | 0 arch/arm64/kvm/config.c | 34 +- arch/arm64/kvm/debug.c | 31 +- arch/arm64/kvm/guest.c | 2 +- arch/arm64/kvm/handle_exit.c | 2 +- arch/arm64/kvm/hyp/Makefile | 6 +- arch/arm64/kvm/hyp/include/hyp/switch.h | 211 ++++- arch/arm64/kvm/hyp/nvhe/switch.c | 4 +- arch/arm64/kvm/hyp/vhe/switch.c | 4 +- arch/arm64/kvm/hypercalls.c | 4 +- arch/arm64/kvm/pmu-direct.c | 464 +++++++++++ arch/arm64/kvm/pmu-emul.c | 678 +--------------- arch/arm64/kvm/pmu.c | 726 ++++++++++++++++++ arch/arm64/kvm/psci.c | 4 +- arch/arm64/kvm/pvtime.c | 2 +- arch/arm64/kvm/reset.c | 3 +- arch/arm64/kvm/sys_regs.c | 110 +-- arch/arm64/kvm/trace_arm.h | 2 +- arch/arm64/kvm/trng.c | 2 +- arch/arm64/kvm/vgic/vgic-debug.c | 2 +- arch/arm64/kvm/vgic/vgic-init.c | 2 +- arch/arm64/kvm/vgic/vgic-irqfd.c | 2 +- arch/arm64/kvm/vgic/vgic-kvm-device.c | 2 +- arch/arm64/kvm/vgic/vgic-mmio-v2.c | 2 +- arch/arm64/kvm/vgic/vgic-mmio-v3.c | 2 +- arch/arm64/kvm/vgic/vgic-mmio.c | 4 +- arch/arm64/kvm/vgic/vgic-v2.c | 2 +- arch/arm64/kvm/vgic/vgic-v3-nested.c | 3 +- arch/arm64/kvm/vgic/vgic-v3.c | 2 +- arch/arm64/kvm/vgic/vgic-v5.c | 2 +- arch/arm64/tools/cpucaps | 1 + arch/arm64/tools/sysreg | 6 +- drivers/perf/arm_pmuv3.c | 137 +++- include/linux/perf/arm_pmu.h | 1 + include/linux/perf/arm_pmuv3.h | 14 +- include/uapi/linux/kvm.h | 1 + tools/include/uapi/linux/kvm.h | 1 + tools/testing/selftests/kvm/Makefile.kvm | 1 + .../selftests/kvm/arm64/vpmu_counter_access.c | 77 +- tools/testing/selftests/kvm/lib/find_bit.c | 1 + 53 files changed, 2049 insertions(+), 831 deletions(-) rename include/kvm/arm_arch_timer.h => arch/arm64/include/asm/kvm_arch_timer.h (98%) rename include/kvm/arm_pmu.h => arch/arm64/include/asm/kvm_pmu.h (61%) rename include/kvm/arm_vgic.h => arch/arm64/include/asm/kvm_vgic.h (100%) rename {include => arch/arm64}/kvm/arm_hypercalls.h (100%) rename {include => arch/arm64}/kvm/arm_psci.h (100%) create mode 100644 arch/arm64/kvm/pmu-direct.c create mode 100644 tools/testing/selftests/kvm/lib/find_bit.c base-commit: ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d -- 2.52.0.239.gd5f0c6e74e-goog

3 weeks, 6 days

4
60
0 0

[PATCH] watchdog: softlockup: panic when lockup duration exceeds N thresholds

by lirongqing

From: Li RongQing <lirongqing(a)baidu.com> The softlockup_panic sysctl is currently a binary option: panic immediately or never panic on soft lockups. Panicking on any soft lockup, regardless of duration, can be overly aggressive for brief stalls that may be caused by legitimate operations. Conversely, never panicking may allow severe system hangs to persist undetected. Extend softlockup_panic to accept an integer threshold, allowing the kernel to panic only when the normalized lockup duration exceeds N watchdog threshold periods. This provides finer-grained control to distinguish between transient delays and persistent system failures. The accepted values are: - 0: Don't panic (unchanged) - 1: Panic when duration >= 1 * threshold (20s default, original behavior) - N > 1: Panic when duration >= N * threshold (e.g., 2 = 40s, 3 = 60s.) The original behavior is preserved for values 0 and 1, maintaining full backward compatibility while allowing systems to tolerate brief lockups while still catching severe, persistent hangs. Signed-off-by: Li RongQing <lirongqing(a)baidu.com> --- Documentation/admin-guide/kernel-parameters.txt | 10 +++++----- arch/arm/configs/aspeed_g5_defconfig | 2 +- arch/arm/configs/pxa3xx_defconfig | 2 +- arch/openrisc/configs/or1klitex_defconfig | 2 +- arch/powerpc/configs/skiroot_defconfig | 2 +- drivers/gpu/drm/ci/arm.config | 2 +- drivers/gpu/drm/ci/arm64.config | 2 +- drivers/gpu/drm/ci/x86_64.config | 2 +- kernel/watchdog.c | 8 +++++--- lib/Kconfig.debug | 13 +++++++------ tools/testing/selftests/bpf/config | 2 +- tools/testing/selftests/wireguard/qemu/kernel.config | 2 +- 12 files changed, 26 insertions(+), 23 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a8d0afd..27c5f96 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6934,12 +6934,12 @@ Kernel parameters softlockup_panic= [KNL] Should the soft-lockup detector generate panics. - Format: 0 | 1 + Format: <int> - A value of 1 instructs the soft-lockup detector - to panic the machine when a soft-lockup occurs. It is - also controlled by the kernel.softlockup_panic sysctl - and CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, which is the + A value of non-zero instructs the soft-lockup detector + to panic the machine when a soft-lockup duration exceeds + N thresholds. It is also controlled by the kernel.softlockup_panic + sysctl and CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, which is the respective build-time switch to that functionality. softlockup_all_cpu_backtrace= diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig index 2e6ea13..ec558e5 100644 --- a/arch/arm/configs/aspeed_g5_defconfig +++ b/arch/arm/configs/aspeed_g5_defconfig @@ -306,7 +306,7 @@ CONFIG_SCHED_STACK_END_CHECK=y CONFIG_PANIC_ON_OOPS=y CONFIG_PANIC_TIMEOUT=-1 CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1 CONFIG_WQ_WATCHDOG=y # CONFIG_SCHED_DEBUG is not set diff --git a/arch/arm/configs/pxa3xx_defconfig b/arch/arm/configs/pxa3xx_defconfig index 07d422f..fb272e3 100644 --- a/arch/arm/configs/pxa3xx_defconfig +++ b/arch/arm/configs/pxa3xx_defconfig @@ -100,7 +100,7 @@ CONFIG_PRINTK_TIME=y CONFIG_DEBUG_KERNEL=y CONFIG_MAGIC_SYSRQ=y CONFIG_DEBUG_SHIRQ=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 # CONFIG_SCHED_DEBUG is not set CONFIG_DEBUG_SPINLOCK=y CONFIG_DEBUG_SPINLOCK_SLEEP=y diff --git a/arch/openrisc/configs/or1klitex_defconfig b/arch/openrisc/configs/or1klitex_defconfig index fb1eb9a..984b0e3 100644 --- a/arch/openrisc/configs/or1klitex_defconfig +++ b/arch/openrisc/configs/or1klitex_defconfig @@ -52,5 +52,5 @@ CONFIG_LSM="lockdown,yama,loadpin,safesetid,integrity,bpf" CONFIG_PRINTK_TIME=y CONFIG_PANIC_ON_OOPS=y CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BUG_ON_DATA_CORRUPTION=y diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig index 2b71a6d..a4114fc 100644 --- a/arch/powerpc/configs/skiroot_defconfig +++ b/arch/powerpc/configs/skiroot_defconfig @@ -289,7 +289,7 @@ CONFIG_SCHED_STACK_END_CHECK=y CONFIG_DEBUG_STACKOVERFLOW=y CONFIG_PANIC_ON_OOPS=y CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_HARDLOCKUP_DETECTOR=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y CONFIG_WQ_WATCHDOG=y diff --git a/drivers/gpu/drm/ci/arm.config b/drivers/gpu/drm/ci/arm.config index 411e814..d7c5167 100644 --- a/drivers/gpu/drm/ci/arm.config +++ b/drivers/gpu/drm/ci/arm.config @@ -52,7 +52,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=n -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=n +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=0 CONFIG_FW_LOADER_COMPRESS=y diff --git a/drivers/gpu/drm/ci/arm64.config b/drivers/gpu/drm/ci/arm64.config index fddfbd4..ea0e307 100644 --- a/drivers/gpu/drm/ci/arm64.config +++ b/drivers/gpu/drm/ci/arm64.config @@ -161,7 +161,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_DETECT_HUNG_TASK=y diff --git a/drivers/gpu/drm/ci/x86_64.config b/drivers/gpu/drm/ci/x86_64.config index 8eaba388..7ac98a7 100644 --- a/drivers/gpu/drm/ci/x86_64.config +++ b/drivers/gpu/drm/ci/x86_64.config @@ -47,7 +47,7 @@ CONFIG_TMPFS=y CONFIG_PROVE_LOCKING=n CONFIG_DEBUG_LOCKDEP=n CONFIG_SOFTLOCKUP_DETECTOR=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_DETECT_HUNG_TASK=y diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 0685e3a..a5fa116 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -363,7 +363,7 @@ static struct cpumask watchdog_allowed_mask __read_mostly; /* Global variables, exported for sysctl */ unsigned int __read_mostly softlockup_panic = - IS_ENABLED(CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC); + CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC; static bool softlockup_initialized __read_mostly; static u64 __read_mostly sample_period; @@ -879,7 +879,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) add_taint(TAINT_SOFTLOCKUP, LOCKDEP_STILL_OK); sys_info(softlockup_si_mask & ~SYS_INFO_ALL_BT); - if (softlockup_panic) + duration = duration / get_softlockup_thresh(); + + if (softlockup_panic && duration >= softlockup_panic) panic("softlockup: hung tasks"); } @@ -1228,7 +1230,7 @@ static const struct ctl_table watchdog_sysctls[] = { .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .extra2 = SYSCTL_INT_MAX, }, { .procname = "softlockup_sys_info", diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index ba36939..17a7a77 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1110,13 +1110,14 @@ config SOFTLOCKUP_DETECTOR_INTR_STORM the CPU stats and the interrupt counts during the "soft lockups". config BOOTPARAM_SOFTLOCKUP_PANIC - bool "Panic (Reboot) On Soft Lockups" + int "Panic (Reboot) On Soft Lockups" depends on SOFTLOCKUP_DETECTOR + default 0 help - Say Y here to enable the kernel to panic on "soft lockups", - which are bugs that cause the kernel to loop in kernel - mode for more than 20 seconds (configurable using the watchdog_thresh - sysctl), without giving other tasks a chance to run. + Set to a non-zero value N to enable the kernel to panic on "soft + lockups", which are bugs that cause the kernel to loop in kernel + mode for more than (N * 20 seconds) (configurable using the + watchdog_thresh sysctl), without giving other tasks a chance to run. The panic can be used in combination with panic_timeout, to cause the system to reboot automatically after a @@ -1124,7 +1125,7 @@ config BOOTPARAM_SOFTLOCKUP_PANIC high-availability systems that have uptime guarantees and where a lockup must be resolved ASAP. - Say N if unsure. + Say 0 if unsure. config HAVE_HARDLOCKUP_DETECTOR_BUDDY bool diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 558839e..2485538 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -1,6 +1,6 @@ CONFIG_BLK_DEV_LOOP=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BPF=y CONFIG_BPF_EVENTS=y CONFIG_BPF_JIT=y diff --git a/tools/testing/selftests/wireguard/qemu/kernel.config b/tools/testing/selftests/wireguard/qemu/kernel.config index 0504c11..bb89d2d 100644 --- a/tools/testing/selftests/wireguard/qemu/kernel.config +++ b/tools/testing/selftests/wireguard/qemu/kernel.config @@ -80,7 +80,7 @@ CONFIG_HARDLOCKUP_DETECTOR=y CONFIG_WQ_WATCHDOG=y CONFIG_DETECT_HUNG_TASK=y CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y -CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y +CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=1 CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1 CONFIG_PANIC_TIMEOUT=-1 CONFIG_STACKTRACE=y -- 2.9.4

3 weeks, 6 days

3
2
0 0

[PATCH v4 0/4] selftests/resctrl: Add Hygon CPUs support and bug fixes

by Xiaochen Shen

The resctrl selftest currently exhibits several failures on Hygon CPUs due to missing vendor detection and edge-case handling specific to Hygon's architecture. This patch series addresses three distinct issues: 1. A division-by-zero crash in SNC detection on some platforms (e.g., Hygon). 2. Missing CPU vendor detection, causing the test to fail with "# Can not get vendor info..." on Hygon CPUs. 3. Incorrect handling of non-contiguous CBM support on Hygon CPUs. These changes enable resctrl selftest to run successfully on Hygon CPUs that support Platform QoS features. Maintainer notes: ----------------- Patch 1: selftests/resctrl: Fix a division by zero error on Hygon - This is a candidate for backport with "Fixes:" tag. Patch 2: selftests/resctrl: Define CPU vendor IDs as bits to match usage - This is *not* a candidate for backport since it is an enhancement and preparatory patch for patch 3. Patch 3: selftests/resctrl: Add CPU vendor detection for Hygon Patch 4: selftests/resctrl: Fix non-contiguous CBM check for Hygon - Even though they are fixes they are *not* candidates for backport since they are based on another patch series (x86/resctrl: Fix Platform QoS issues for Hygon) which is in process of being added to resctrl. ----------------- Changelog: v4: - Cover letter: add maintainer notes outlining how these patches to be handled (Reinette). - Re-organize the patch series to move original patch 3 to the beginning of series. The patch order has changed between v3 and v4 (Reinette): v3 -> v4 patch #3 -> patch #1 patch #1 -> patch #2 patch #2 -> patch #3 patch #4 -> patch #4 - Patch 2: 1. Resolve a conflict against latest upstream kernel (Reinette). 2. Fix a nit to maintain the reverse fir ordering of variables in detect_vendor() (Reinette). - Patch 3: add Reviewed-by: Reinette Chatre <reinette.chatre(a)intel.com> - Patch 4: move the maintainer note into the cover letter (Reinette). v3: - Patch 1: 1. Update the return types of detect_vendor() and get_vendor() from 'int' to 'unsigned int' to align with their usage as bitmask values and to prevent potentially risky type conversions (Fenghua). 2. Split the code changes of "define CPU vendor IDs as bits to match usage" from original patch 1 into a separate patch (this patch, suggested by Fenghua and Reinette). 3. Introduce the flag 'initialized' to simplify the get_vendor() -> detect_vendor() logic (Reinette). - Patch 2 (original patch 1): 1. Move the code changes of "define CPU vendor IDs as bits to match usage" into patch 1. - Patch 3 (original patch 2): 1. Fix a nit of code comment for affected platforms (Fenghua). 2. Add Reviewed-by: Fenghua Yu <fenghuay(a)nvidia.com>. - Patch 4 (original patch 3): 1. Fix a nit to avoid calling get_vendor() twice (Fenghua). 2. Add Reviewed-by: Fenghua Yu <fenghuay(a)nvidia.com>. v2: - Patch 1: switch all of the vendor id bitmasks to use BIT() (Reinette) - Patch 2: add Reviewed-by: Reinette Chatre <reinette.chatre(a)intel.com> - Patch 3: add Reviewed-by: Reinette Chatre <reinette.chatre(a)intel.com> add a maintainer note to highlight it is not a candidate for backport (Reinette) Xiaochen Shen (4): selftests/resctrl: Fix a division by zero error on Hygon selftests/resctrl: Define CPU vendor IDs as bits to match usage selftests/resctrl: Add CPU vendor detection for Hygon selftests/resctrl: Fix non-contiguous CBM check for Hygon tools/testing/selftests/resctrl/cat_test.c | 6 ++-- tools/testing/selftests/resctrl/resctrl.h | 8 ++++-- .../testing/selftests/resctrl/resctrl_tests.c | 28 +++++++++++++------ tools/testing/selftests/resctrl/resctrlfs.c | 10 +++++++ 4 files changed, 39 insertions(+), 13 deletions(-) -- 2.47.3

3 weeks, 6 days

2
6
0 0

[PATCH bpf-next v3 0/6] Add cryptographic hash and signature verification kfuncs to BPF

by Daniel Hodges

This series extends BPF's cryptographic capabilities by adding kfuncs for SHA hashing and ECDSA signature verification. These functions enable BPF programs to perform cryptographic operations for use cases such as content verification, integrity checking, and data authentication. BPF programs increasingly need to verify data integrity and authenticity in networking, security, and observability contexts. While BPF already supports symmetric encryption/decryption, it lacks support for: 1. Cryptographic hashing - needed for content verification, fingerprinting, and preparing message digests for signature operations 2. Asymmetric signature verification - needed to verify signed data without requiring the signing key in the datapath These capabilities enable use cases such as: - Verifying signed network packets or application data in XDP/TC programs - Implementing integrity checks in tracing and security monitoring - Building zero-trust security models where BPF programs verify credentials - Content-addressed storage and deduplication in BPF-based filesystems Implementation: The implementation follows BPF's existing crypto patterns: 1. Uses bpf_dynptr for safe memory access without page fault risks 2. Leverages the kernel's existing crypto library (lib/crypto/sha256.c and crypto/ecdsa.c) rather than reimplementing algorithms 3. Provides context-based API for ECDSA to enable key reuse and support multiple program types (syscall, XDP, TC) 4. Includes comprehensive selftests with NIST test vectors Patch 1: bpf: Extend bpf_crypto_type with hash operations - Adds hash operation callbacks to bpf_crypto_type structure - Adds hash() and digestsize() function pointers - Must come before crypto module to maintain bisectability Patch 2: crypto: Add BPF hash algorithm type registration module - Adds bpf_crypto_shash module in crypto/ subsystem - Registers hash type with BPF crypto infrastructure - Enables hash algorithm access through unified bpf_crypto_type interface - Implements callbacks: alloc_tfm, free_tfm, hash, digestsize, get_flags - Manages shash_desc lifecycle internally Patch 3: bpf: Add SHA hash kfunc for cryptographic hashing - Adds bpf_crypto_hash() kfunc for SHA-256/384/512 - Updates bpf_crypto_ctx_create() to support keyless operations - Protected by CONFIG_CRYPTO_HASH2 guards - Uses kernel's crypto library implementations - Fixed u64 types for dynptr sizes to prevent truncation Patch 4: selftests/bpf: Add tests for bpf_crypto_hash kfunc - Tests basic functionality with NIST "abc" test vectors - Validates error handling for invalid parameters (zero-length input) - Ensures correct hash output for SHA-256, SHA-384, and SHA-512 - Adds CONFIG_CRYPTO_HASH2 and CONFIG_CRYPTO_SHA512 to selftest config - Refactored test setup code to reduce duplication Patch 5: bpf: Add ECDSA signature verification kfuncs - Context-based API: bpf_ecdsa_ctx_create/acquire/release pattern - Supports NIST curves (P-256, P-384, P-521) - Adds bpf_ecdsa_verify() for signature verification - Includes size query functions: keysize, digestsize, maxsize - Enables use in non-sleepable contexts via pre-allocated contexts - Uses crypto_sig API with p1363 format (r || s signatures) Patch 6: selftests/bpf: Add tests for ECDSA signature verification - Tests valid signature acceptance with RFC 6979 test vectors for P-256 - Tests invalid signature rejection - Tests size query functions (keysize, digestsize, maxsize) - Uses well-known NIST test vectors with "sample" message - Adds CONFIG_CRYPTO_ECDSA to selftest config v2: - Fixed redundant __bpf_dynptr_is_rdonly() checks (Vadim) - Added BPF hash algorithm type registration module in crypto/ subsystem - Added CONFIG_CRYPTO_HASH2 guards around bpf_crypto_hash() kfunc and its BTF registration, matching the pattern used for CONFIG_CRYPTO_ECDSA - Added mandatory digestsize validation for hash operations v3: - Fixed patch ordering - header changes now in separate first commit before crypto module to ensure bisectability (bot+bpf-ci) - Fixed type mismatch - changed u32 to u64 for dynptr sizes in bpf_crypto_hash() to match __bpf_dynptr_size() return type (Mykyta) - Added CONFIG_CRYPTO_ECDSA to selftest config (Song) - Refactored test code duplication with setup_skel() helper (Song) - Added copyright notices to all new files Daniel Hodges (6): bpf: Extend bpf_crypto_type with hash operations crypto: Add BPF hash algorithm type registration module bpf: Add SHA hash kfunc for cryptographic hashing selftests/bpf: Add tests for bpf_crypto_hash kfunc bpf: Add ECDSA signature verification kfuncs selftests/bpf: Add tests for ECDSA signature verification kfuncs crypto/Makefile | 3 + crypto/bpf_crypto_shash.c | 95 ++++++ include/linux/bpf_crypto.h | 2 + kernel/bpf/crypto.c | 306 +++++++++++++++++- tools/testing/selftests/bpf/config | 3 + .../selftests/bpf/prog_tests/crypto_hash.c | 147 +++++++++ .../selftests/bpf/prog_tests/ecdsa_verify.c | 75 +++++ .../testing/selftests/bpf/progs/crypto_hash.c | 142 ++++++++ .../selftests/bpf/progs/ecdsa_verify.c | 160 +++++++++ 9 files changed, 925 insertions(+), 8 deletions(-) create mode 100644 crypto/bpf_crypto_shash.c create mode 100644 tools/testing/selftests/bpf/prog_tests/crypto_hash.c create mode 100644 tools/testing/selftests/bpf/prog_tests/ecdsa_verify.c create mode 100644 tools/testing/selftests/bpf/progs/crypto_hash.c create mode 100644 tools/testing/selftests/bpf/progs/ecdsa_verify.c -- 2.51.0

3 weeks, 6 days

5
14
0 0

[PATCH net v3] selftests: net: fix "buffer overflow detected" for tap.c

by Alice C. Munduruca

When the selftest 'tap.c' is compiled with '-D_FORTIFY_SOURCE=3', the strcpy() in rtattr_add_strsz() is replaced with a checked version which causes the test to consistently fail when compiled with toolchains for which this option is enabled by default. TAP version 13 1..3 # Starting 3 tests from 1 test cases. # RUN tap.test_packet_valid_udp_gso ... *** buffer overflow detected ***: terminated # test_packet_valid_udp_gso: Test terminated by assertion # FAIL tap.test_packet_valid_udp_gso not ok 1 tap.test_packet_valid_udp_gso # RUN tap.test_packet_valid_udp_csum ... *** buffer overflow detected ***: terminated # test_packet_valid_udp_csum: Test terminated by assertion # FAIL tap.test_packet_valid_udp_csum not ok 2 tap.test_packet_valid_udp_csum # RUN tap.test_packet_crash_tap_invalid_eth_proto ... *** buffer overflow detected ***: terminated # test_packet_crash_tap_invalid_eth_proto: Test terminated by assertion # FAIL tap.test_packet_crash_tap_invalid_eth_proto not ok 3 tap.test_packet_crash_tap_invalid_eth_proto # FAILED: 0 / 3 tests passed. # Totals: pass:0 fail:3 xfail:0 xpass:0 skip:0 error:0 A buffer overflow is detected by the fortified glibc __strcpy_chk() since the __builtin_object_size() of `RTA_DATA(rta)` is incorrectly reported as 1, even though there is ample space in its bounding buffer `req`. Additionally, given that IFLA_IFNAME also expects a null-terminated string, callers of rtaddr_add_str{,sz}() could simply use the rtaddr_add_strsz() variant. (which has been renamed to remove the trailing `sz`) memset() has been used for this function since it is unchecked and thus circumvents the issue discussed in the previous paragraph. Fixes: 2e64fe4624d1 ("selftests: add few test cases for tap driver") Signed-off-by: Alice C. Munduruca <alice.munduruca(a)canonical.com> Reviewed-by: Cengiz Can <cengiz.can(a)canonical.com> --- tools/testing/selftests/net/tap.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/net/tap.c b/tools/testing/selftests/net/tap.c index 247c3b3ac1c9..51a209014f1c 100644 --- a/tools/testing/selftests/net/tap.c +++ b/tools/testing/selftests/net/tap.c @@ -56,18 +56,12 @@ static void rtattr_end(struct nlmsghdr *nh, struct rtattr *attr) static struct rtattr *rtattr_add_str(struct nlmsghdr *nh, unsigned short type, const char *s) { - struct rtattr *rta = rtattr_add(nh, type, strlen(s)); + unsigned int strsz = strlen(s) + 1; + struct rtattr *rta; - memcpy(RTA_DATA(rta), s, strlen(s)); - return rta; -} - -static struct rtattr *rtattr_add_strsz(struct nlmsghdr *nh, unsigned short type, - const char *s) -{ - struct rtattr *rta = rtattr_add(nh, type, strlen(s) + 1); + rta = rtattr_add(nh, type, strsz); - strcpy(RTA_DATA(rta), s); + memcpy(RTA_DATA(rta), s, strsz); return rta; } @@ -119,7 +113,7 @@ static int dev_create(const char *dev, const char *link_type, link_info = rtattr_begin(&req.nh, IFLA_LINKINFO); - rtattr_add_strsz(&req.nh, IFLA_INFO_KIND, link_type); + rtattr_add_str(&req.nh, IFLA_INFO_KIND, link_type); if (fill_info_data) { info_data = rtattr_begin(&req.nh, IFLA_INFO_DATA); -- 2.48.1

4 weeks

2
1
0 0

[PATCH net 0/2] selftests: drv-net: psp: fix templated test names in psp.py

by Daniel Zahka

The templated test names in psp.py had a bug that was not exposed until 80970e0fc07e ("selftests: net: py: extract the case generation logic") changed the order of test case evaluation and test case name extraction. The test cases created in psp_ip_ver_test_builder() and ipver_test_builder() were only assigning formatted names to the test cases they returned, when the test itself was run. This series moves the test case naming to the point where the test function is created. Using netdevsim psp: Before: ./tools/testing/selftests/drivers/net/psp.py TAP version 13 1..28 ok 1 psp.test_case ok 2 psp.test_case ok 3 psp.test_case ok 4 psp.test_case ok 5 psp.test_case ok 6 psp.test_case ok 7 psp.test_case ok 8 psp.test_case ok 9 psp.test_case ok 10 psp.test_case ok 11 psp.dev_list_devices ... ok 28 psp.removal_device_bi # Totals: pass:28 fail:0 xfail:0 xpass:0 skip:0 error:0 # # Responder logs (0): # STDERR: # Set PSP enable on device 3 to 0xf # Set PSP enable on device 3 to 0x0 After: ./tools/testing/selftests/drivers/net/psp.py TAP version 13 1..28 ok 1 psp.data_basic_send_v0_ip4 ok 2 psp.data_basic_send_v0_ip6 ok 3 psp.data_basic_send_v1_ip4 ok 4 psp.data_basic_send_v1_ip6 ok 5 psp.data_basic_send_v2_ip4 ok 6 psp.data_basic_send_v2_ip6 ok 7 psp.data_basic_send_v3_ip4 ok 8 psp.data_basic_send_v3_ip6 ok 9 psp.data_mss_adjust_ip4 ok 10 psp.data_mss_adjust_ip6 ok 11 psp.dev_list_devices ... ok 28 psp.removal_device_bi # Totals: pass:28 fail:0 xfail:0 xpass:0 skip:0 error:0 # # Responder logs (0): # STDERR: # Set PSP enable on device 3 to 0xf # Set PSP enable on device 3 to 0x0 Signed-off-by: Daniel Zahka <daniel.zahka(a)gmail.com> --- Daniel Zahka (2): selftests: drv-net: psp: fix templated test names in psp_ip_ver_test_builder() selftests: drv-net: psp: fix test names in ipver_test_builder() tools/testing/selftests/drivers/net/psp.py | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- base-commit: 885bebac9909994050bbbeed0829c727e42bd1b7 change-id: 20251212-psp-test-fix-f0816c40a2c1 Best regards, -- Daniel Zahka <daniel.zahka(a)gmail.com>

4 weeks

1
2
0 0

[PATCH] kselftest/anon_inode: replace null pointers with empty arrays

by Clint George

Make use of empty (NULL-terminated) array instead of NULL pointer to avoid compiler errors while maintaining the behavior of the function intact Signed-off-by: Clint George <clintbgeorge(a)gmail.com> --- [] Testing: The diff between before and after of running the kselftest test of the module shows no regression on system with x86 architecture Let me know if any more testing is needed to be done [] Error log: ~/Desktop/kernel-dev/linux-v1/tools/testing/selftests/filesystems$ make LLVM=1 W=1 CC devpts_pts CC file_stressor CC anon_inode_test anon_inode_test.c:45:37: warning: null passed to a callee that requires a non-null argument [-Wnonnull] 45 | ASSERT_LT(execveat(fd_context, "", NULL, NULL, AT_EMPTY_PATH), 0); | ^~~~ /usr/lib/llvm-18/lib/clang/18/include/__stddef_null.h:26:14: note: expanded from macro 'NULL' 26 | #define NULL ((void*)0) | ^~~~~~~~~~ /home/clint/Desktop/kernel-dev/linux-v1/tools/testing/selftests/../../../tools/testing/selftests/kselftest_harness.h:535:11: note: expanded from macro 'ASSERT_LT' 535 | __EXPECT(expected, #expected, seen, #seen, <, 1) | ^~~~~~~~ /home/clint/Desktop/kernel-dev/linux-v1/tools/testing/selftests/../../../tools/testing/selftests/kselftest_harness.h:758:33: note: expanded from macro '__EXPECT' 758 | __typeof__(_expected) __exp = (_expected); \ | ^~~~~~~~~ 1 warning generated. tools/testing/selftests/filesystems/anon_inode_test.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/filesystems/anon_inode_test.c b/tools/testing/selftests/filesystems/anon_inode_test.c index 94c6c81c2..2c4c50500 100644 --- a/tools/testing/selftests/filesystems/anon_inode_test.c +++ b/tools/testing/selftests/filesystems/anon_inode_test.c @@ -42,7 +42,10 @@ TEST(anon_inode_no_exec) fd_context = sys_fsopen("tmpfs", 0); ASSERT_GE(fd_context, 0); - ASSERT_LT(execveat(fd_context, "", NULL, NULL, AT_EMPTY_PATH), 0); + char *const empty_argv[] = {NULL}; + char *const empty_envp[] = {NULL}; + + ASSERT_LT(execveat(fd_context, "", empty_argv, empty_envp, AT_EMPTY_PATH), 0); ASSERT_EQ(errno, EACCES); EXPECT_EQ(close(fd_context), 0); -- 2.43.0

4 weeks

1
0
0 0

[PATCH] kselftest/coredump: use __builtin_trap() instead of null pointer

by Clint George

Use __builtin_trap() to truly crash the program instead of dereferencing null pointer which may be optimized by the compiler preventing the crash from occurring Signed-off-by: Clint George <clintbgeorge(a)gmail.com> --- [] Testing: The diff between before and after of running the kselftest test of the module shows no regression on system with x86 architecture Let me know if any more testing is needed to be done [] Error log: ~/Desktop/kernel-dev/linux-v1/tools/testing/selftests/coredump$ make LLVM=1 W=1 CC stackdump_test coredump_test_helpers.c:59:6: warning: indirection of non-volatile null pointer will be deleted, not trap [-Wnull-dereference] 59 | i = *(int *)NULL; | ^~~~~~~~~~~~ coredump_test_helpers.c:59:6: note: consider using __builtin_trap() or qualifying pointer with 'volatile' 1 warning generated. CC coredump_socket_test coredump_test_helpers.c:59:6: warning: indirection of non-volatile null pointer will be deleted, not trap [-Wnull-dereference] 59 | i = *(int *)NULL; | ^~~~~~~~~~~~ coredump_test_helpers.c:59:6: note: consider using __builtin_trap() or qualifying pointer with 'volatile' 1 warning generated. CC coredump_socket_protocol_test coredump_test_helpers.c:59:6: warning: indirection of non-volatile null pointer will be deleted, not trap [-Wnull-dereference] 59 | i = *(int *)NULL; | ^~~~~~~~~~~~ coredump_test_helpers.c:59:6: note: consider using __builtin_trap() or qualifying pointer with 'volatile' 1 warning generated. tools/testing/selftests/coredump/coredump_test_helpers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/coredump/coredump_test_helpers.c b/tools/testing/selftests/coredump/coredump_test_helpers.c index a6f6d5f2a..5c8adee63 100644 --- a/tools/testing/selftests/coredump/coredump_test_helpers.c +++ b/tools/testing/selftests/coredump/coredump_test_helpers.c @@ -56,7 +56,7 @@ void crashing_child(void) pthread_create(&thread, NULL, do_nothing, NULL); /* crash on purpose */ - i = *(int *)NULL; + __builtin_trap(); } int create_detached_tmpfs(void) -- 2.43.0

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[PATCH] kselftest/kublk: include message in _Static_assert for C11 compatibility

by Clint George

Add descriptive message in the _Static_assert to comply with the C11 standard requirement to prevent compiler from throwing out error. The compiler throws an error when _Static_assert is used without a message as that is a C23 extension. Signed-off-by: Clint George <clintbgeorge(a)gmail.com> --- [] Testing: The diff between before and after of running the kselftest test of the module shows no regression on system with x86 architecture Let me know if any more testing is needed to be done [] Error log: ~/Desktop/kernel-dev/linux-v1/tools/testing/selftests/ublk$ make LLVM=1 W=1 CC kublk In file included from kublk.c:6: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. In file included from null.c:3: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. In file included from file_backed.c:3: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. In file included from common.c:3: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. In file included from stripe.c:3: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. In file included from fault_inject.c:11: ./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions] 220 | _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); | ^ | , "" 1 error generated. make: *** [../lib.mk:225: /home/clint/Desktop/kernel-dev/linux-v1/tools/testing/selftests/ublk/kublk] Error 1 tools/testing/selftests/ublk/kublk.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/ublk/kublk.h b/tools/testing/selftests/ublk/kublk.h index fe42705c6..e5eb5f762 100644 --- a/tools/testing/selftests/ublk/kublk.h +++ b/tools/testing/selftests/ublk/kublk.h @@ -217,7 +217,7 @@ static inline __u64 build_user_data(unsigned tag, unsigned op, unsigned tgt_data, unsigned q_id, unsigned is_target_io) { /* we only have 7 bits to encode q_id */ - _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7); + _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7, "UBLK_MAX_QUEUES_SHIFT must be <= 7"); assert(!(tag >> 16) && !(op >> 8) && !(tgt_data >> 16) && !(q_id >> 7)); return tag | (op << 16) | (tgt_data << 24) | -- 2.43.0

4 weeks

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