- Linux-kselftest-mirror - lists.linaro.org

[PATCH v2 0/4] KVM: selftests: add powerpc support

by Nicholas Piggin

This series adds initial KVM selftests support for powerpc (64-bit, BookS, radix MMU). Since v1: - Update MAINTAINERS KVM PPC entry to include kvm selftests. - Fixes and cleanups from Sean's review including new patch 1. - Add 4K guest page support requiring new patch 2. Thanks, Nick Nicholas Piggin (4): KVM: selftests: Move pgd_created check into virt_pgd_alloc KVM: selftests: Add aligned guest physical page allocator KVM: PPC: selftests: add support for powerpc KVM: PPC: selftests: add selftests sanity tests MAINTAINERS | 2 + tools/testing/selftests/kvm/Makefile | 15 + .../selftests/kvm/include/kvm_util_base.h | 27 ++ .../selftests/kvm/include/powerpc/hcall.h | 21 + .../selftests/kvm/include/powerpc/ppc_asm.h | 32 ++ .../selftests/kvm/include/powerpc/processor.h | 33 ++ .../selftests/kvm/lib/aarch64/processor.c | 4 - tools/testing/selftests/kvm/lib/guest_modes.c | 3 + tools/testing/selftests/kvm/lib/kvm_util.c | 56 ++- .../selftests/kvm/lib/powerpc/handlers.S | 93 ++++ .../testing/selftests/kvm/lib/powerpc/hcall.c | 45 ++ .../selftests/kvm/lib/powerpc/processor.c | 429 ++++++++++++++++++ .../testing/selftests/kvm/lib/powerpc/ucall.c | 30 ++ .../selftests/kvm/lib/riscv/processor.c | 4 - .../selftests/kvm/lib/s390x/processor.c | 4 - .../selftests/kvm/lib/x86_64/processor.c | 7 +- tools/testing/selftests/kvm/powerpc/helpers.h | 46 ++ .../testing/selftests/kvm/powerpc/null_test.c | 166 +++++++ .../selftests/kvm/powerpc/rtas_hcall.c | 146 ++++++ 19 files changed, 1129 insertions(+), 34 deletions(-) create mode 100644 tools/testing/selftests/kvm/include/powerpc/hcall.h create mode 100644 tools/testing/selftests/kvm/include/powerpc/ppc_asm.h create mode 100644 tools/testing/selftests/kvm/include/powerpc/processor.h create mode 100644 tools/testing/selftests/kvm/lib/powerpc/handlers.S create mode 100644 tools/testing/selftests/kvm/lib/powerpc/hcall.c create mode 100644 tools/testing/selftests/kvm/lib/powerpc/processor.c create mode 100644 tools/testing/selftests/kvm/lib/powerpc/ucall.c create mode 100644 tools/testing/selftests/kvm/powerpc/helpers.h create mode 100644 tools/testing/selftests/kvm/powerpc/null_test.c create mode 100644 tools/testing/selftests/kvm/powerpc/rtas_hcall.c -- 2.40.0

2 years

3
7
0 0

[linux-next:master] BUILD REGRESSION 5c875096d59010cee4e00da1f9c7bdb07a025dc2

by kernel test robot

tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master branch HEAD: 5c875096d59010cee4e00da1f9c7bdb07a025dc2 Add linux-next specific files for 20230628 Error/Warning reports: https://lore.kernel.org/oe-kbuild-all/202306122223.HHER4zOo-lkp@intel.com https://lore.kernel.org/oe-kbuild-all/202306282012.sPQAuAN7-lkp@intel.com Error/Warning: (recently discovered and may have been fixed) ERROR: modpost: "clk_register_fixed_rate" [drivers/regulator/raa215300.ko] undefined! ERROR: modpost: "clk_unregister_fixed_rate" [drivers/regulator/raa215300.ko] undefined! arch/parisc/kernel/pdt.c:66:6: warning: no previous prototype for 'arch_report_meminfo' [-Wmissing-prototypes] drivers/char/mem.c:164:25: error: implicit declaration of function 'unxlate_dev_mem_ptr'; did you mean 'xlate_dev_mem_ptr'? [-Werror=implicit-function-declaration] lib/kunit/executor_test.c:138:4: warning: cast from 'void (*)(const void *)' to 'kunit_action_t *' (aka 'void (*)(void *)') converts to incompatible function type [-Wcast-function-type-strict] lib/kunit/test.c:775:38: warning: cast from 'void (*)(const void *)' to 'kunit_action_t *' (aka 'void (*)(void *)') converts to incompatible function type [-Wcast-function-type-strict] Unverified Error/Warning (likely false positive, please contact us if interested): drivers/usb/cdns3/cdns3-starfive.c:23: warning: expecting prototype for cdns3(). Prototype was for USB_STRAP_HOST() instead fs/btrfs/volumes.c:6407 btrfs_map_block() error: we previously assumed 'mirror_num_ret' could be null (see line 6244) net/wireless/scan.c:373 cfg80211_gen_new_ie() warn: potential spectre issue 'sub->data' [r] net/wireless/scan.c:397 cfg80211_gen_new_ie() warn: possible spectre second half. 'ext_id' {standard input}: Error: local label `"2" (instance number 9 of a fb label)' is not defined {standard input}:1097: Error: pcrel too far Error/Warning ids grouped by kconfigs: gcc_recent_errors |-- i386-randconfig-m021-20230628 | `-- fs-btrfs-volumes.c-btrfs_map_block()-error:we-previously-assumed-mirror_num_ret-could-be-null-(see-line-) |-- m68k-randconfig-r054-20230628 | |-- ERROR:clk_register_fixed_rate-drivers-regulator-raa215300.ko-undefined | `-- ERROR:clk_unregister_fixed_rate-drivers-regulator-raa215300.ko-undefined |-- parisc-allyesconfig | `-- arch-parisc-kernel-pdt.c:warning:no-previous-prototype-for-arch_report_meminfo |-- parisc-defconfig | `-- arch-parisc-kernel-pdt.c:warning:no-previous-prototype-for-arch_report_meminfo |-- parisc-randconfig-r026-20230628 | `-- arch-parisc-kernel-pdt.c:warning:no-previous-prototype-for-arch_report_meminfo |-- parisc64-defconfig | `-- arch-parisc-kernel-pdt.c:warning:no-previous-prototype-for-arch_report_meminfo |-- riscv-allmodconfig | `-- drivers-usb-cdns3-cdns3-starfive.c:warning:expecting-prototype-for-cdns3().-Prototype-was-for-USB_STRAP_HOST()-instead |-- riscv-allyesconfig | `-- drivers-usb-cdns3-cdns3-starfive.c:warning:expecting-prototype-for-cdns3().-Prototype-was-for-USB_STRAP_HOST()-instead |-- sh-allmodconfig | |-- drivers-char-mem.c:error:implicit-declaration-of-function-unxlate_dev_mem_ptr | |-- standard-input:Error:local-label-(instance-number-of-a-fb-label)-is-not-defined | `-- standard-input:Error:pcrel-too-far |-- sh-randconfig-r025-20230628 | `-- drivers-char-mem.c:error:implicit-declaration-of-function-unxlate_dev_mem_ptr |-- sh-rsk7203_defconfig | `-- drivers-char-mem.c:error:implicit-declaration-of-function-unxlate_dev_mem_ptr `-- x86_64-randconfig-m001-20230628 |-- net-wireless-scan.c-cfg80211_gen_new_ie()-warn:possible-spectre-second-half.-ext_id `-- net-wireless-scan.c-cfg80211_gen_new_ie()-warn:potential-spectre-issue-sub-data-r clang_recent_errors |-- arm-randconfig-r012-20230628 | `-- lib-kunit-test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type |-- hexagon-randconfig-r045-20230628 | |-- lib-kunit-executor_test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type | `-- lib-kunit-test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type |-- s390-randconfig-r001-20230628 | `-- lib-kunit-test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type `-- s390-randconfig-r003-20230628 |-- lib-kunit-executor_test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type `-- lib-kunit-test.c:warning:cast-from-void-(-)(const-void-)-to-kunit_action_t-(aka-void-(-)(void-)-)-converts-to-incompatible-function-type elapsed time: 731m configs tested: 124 configs skipped: 3 tested configs: alpha allyesconfig gcc alpha defconfig gcc alpha randconfig-r014-20230628 gcc alpha randconfig-r023-20230628 gcc alpha randconfig-r035-20230628 gcc arc allyesconfig gcc arc defconfig gcc arc nsimosci_defconfig gcc arc randconfig-r034-20230628 gcc arc randconfig-r043-20230628 gcc arm allmodconfig gcc arm allyesconfig gcc arm defconfig gcc arm imx_v4_v5_defconfig clang arm neponset_defconfig clang arm randconfig-r004-20230628 gcc arm randconfig-r005-20230628 gcc arm randconfig-r006-20230628 gcc arm randconfig-r012-20230628 clang arm randconfig-r046-20230628 clang arm versatile_defconfig clang arm vf610m4_defconfig gcc arm64 allyesconfig gcc arm64 defconfig gcc csky defconfig gcc hexagon randconfig-r041-20230628 clang hexagon randconfig-r045-20230628 clang i386 allyesconfig gcc i386 buildonly-randconfig-r004-20230628 clang i386 buildonly-randconfig-r005-20230628 clang i386 buildonly-randconfig-r006-20230628 clang i386 debian-10.3 gcc i386 defconfig gcc i386 randconfig-i001-20230628 clang i386 randconfig-i002-20230628 clang i386 randconfig-i003-20230628 clang i386 randconfig-i004-20230628 clang i386 randconfig-i005-20230628 clang i386 randconfig-i006-20230628 clang i386 randconfig-i011-20230628 gcc i386 randconfig-i012-20230628 gcc i386 randconfig-i013-20230628 gcc i386 randconfig-i014-20230628 gcc i386 randconfig-i015-20230628 gcc i386 randconfig-i016-20230628 gcc loongarch allmodconfig gcc loongarch allnoconfig gcc loongarch defconfig gcc m68k allmodconfig gcc m68k allyesconfig gcc m68k defconfig gcc m68k m5407c3_defconfig gcc microblaze randconfig-r002-20230628 gcc mips allmodconfig gcc mips allyesconfig gcc mips gcw0_defconfig gcc mips xway_defconfig gcc nios2 defconfig gcc nios2 randconfig-r031-20230628 gcc parisc allyesconfig gcc parisc defconfig gcc parisc randconfig-r026-20230628 gcc parisc64 defconfig gcc powerpc adder875_defconfig gcc powerpc allmodconfig gcc powerpc allnoconfig gcc powerpc bamboo_defconfig gcc powerpc currituck_defconfig gcc powerpc gamecube_defconfig clang powerpc mpc512x_defconfig clang powerpc randconfig-r024-20230628 gcc powerpc tqm8xx_defconfig gcc riscv allmodconfig gcc riscv allnoconfig gcc riscv allyesconfig gcc riscv defconfig gcc riscv randconfig-r042-20230628 gcc riscv rv32_defconfig gcc s390 allmodconfig gcc s390 allyesconfig gcc s390 defconfig gcc s390 randconfig-r001-20230628 clang s390 randconfig-r003-20230628 clang s390 randconfig-r021-20230628 gcc s390 randconfig-r044-20230628 gcc sh allmodconfig gcc sh randconfig-r025-20230628 gcc sh rsk7203_defconfig gcc sh sh7757lcr_defconfig gcc sparc allyesconfig gcc sparc defconfig gcc sparc randconfig-r011-20230628 gcc sparc randconfig-r032-20230628 gcc sparc64 randconfig-r033-20230628 gcc sparc64 randconfig-r036-20230628 gcc um allmodconfig clang um allnoconfig clang um allyesconfig clang um defconfig gcc um i386_defconfig gcc um x86_64_defconfig gcc x86_64 allyesconfig gcc x86_64 buildonly-randconfig-r001-20230628 clang x86_64 buildonly-randconfig-r002-20230628 clang x86_64 buildonly-randconfig-r003-20230628 clang x86_64 defconfig gcc x86_64 kexec gcc x86_64 randconfig-r015-20230628 gcc x86_64 randconfig-x001-20230628 gcc x86_64 randconfig-x002-20230628 gcc x86_64 randconfig-x003-20230628 gcc x86_64 randconfig-x004-20230628 gcc x86_64 randconfig-x005-20230628 gcc x86_64 randconfig-x006-20230628 gcc x86_64 randconfig-x011-20230628 clang x86_64 randconfig-x012-20230628 clang x86_64 randconfig-x013-20230628 clang x86_64 randconfig-x014-20230628 clang x86_64 randconfig-x015-20230628 clang x86_64 randconfig-x016-20230628 clang x86_64 rhel-8.3-rust clang x86_64 rhel-8.3 gcc xtensa randconfig-r016-20230628 gcc xtensa randconfig-r022-20230628 gcc -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki

2 years

1
0
0 0

SSVE selftests failing unexpectedly

by Will Deacon

Hi Mark, While debugging the SME issue reported in CI, I noticed that the streaming SVE tests are failing on the fastmodel because of an unexpected SIGILL. For example: will:arm64/signal$ ./ssve_za_regs # Streaming SVE registers :: Check that we get the right Streaming SVE registers reported Registered handlers for all signals. Detected MINSTKSIGSZ:4720 Required Features: [ SME ] supported Incompatible Features: [] absent Testcase initialized. Testing VL 64 -- RX UNEXPECTED SIGNAL: 4 ==>> completed. FAIL(0) The signal is injected because we get an SME trap due to an fpsimd, sve or sve2 instruction being used in streaming mode (ESR is 0x76000001). I did a bit of digging and it looks like this is my libc using a vector DUP instruction in memset: #0 __memset_generic () at ../sysdeps/aarch64/memset.S:37 #1 0x0000aaaaaaaa1170 in get_current_context (dest_sz=131072, dest_uc=0xaaaaaeab6ba0 <context>, td=0xaaaaaaab50f0 <tde>) at ./test_signals_utils.h:69 #2 do_one_sme_vl (si=<optimized out>, uc=<optimized out>, vl=64, td=0xaaaaaaab50f0 <tde>) at testcases/ssve_za_regs.c:90 #3 sme_regs (td=0xaaaaaaab50f0 <tde>, si=<optimized out>, uc=<optimized out>) at testcases/ssve_za_regs.c:145 #4 0x0000aaaaaaaa0ed0 in main (argc=<optimized out>, argv=<optimized out>) at test_signals.c:21 Dump of assembler code for function __memset_generic: => 0x0000fffff7edfb00 <+0>: dup v0.16b, w1 The easy option would be to require FA64 for these tests, but I guess it would be better to exit streaming mode. Please can you have a look? Thanks, Will

2 years

2
1
0 0

[PATCH] selftests/zram: avoid subshells and bc for ratio calculations

by David Disseldorp

Awk is already called for /sys/block/zram#/mm_stat parsing, so use it to also perform the floating point capacity vs consumption ratio calculations. The test output is unchanged. This allows bc to be dropped as a dependency for the zram selftests. Signed-off-by: David Disseldorp <ddiss(a)suse.de> --- tools/testing/selftests/zram/zram01.sh | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/zram/zram01.sh b/tools/testing/selftests/zram/zram01.sh index 8f4affe34f3e4..df1b1d4158989 100755 --- a/tools/testing/selftests/zram/zram01.sh +++ b/tools/testing/selftests/zram/zram01.sh @@ -33,7 +33,7 @@ zram_algs="lzo" zram_fill_fs() { - for i in $(seq $dev_start $dev_end); do + for ((i = $dev_start; i <= $dev_end && !ERR_CODE; i++)); do echo "fill zram$i..." local b=0 while [ true ]; do @@ -44,15 +44,13 @@ zram_fill_fs() done echo "zram$i can be filled with '$b' KB" - local mem_used_total=`awk '{print $3}' "/sys/block/zram$i/mm_stat"` - local v=$((100 * 1024 * $b / $mem_used_total)) - if [ "$v" -lt 100 ]; then - echo "FAIL compression ratio: 0.$v:1" - ERR_CODE=-1 - return - fi - - echo "zram compression ratio: $(echo "scale=2; $v / 100 " | bc):1: OK" + awk -v b="$b" '{ v = (100 * 1024 * b / $3) } END { + if (v < 100) { + printf "FAIL compression ratio: 0.%u:1\n", v + exit 1 + } + printf "zram compression ratio: %.2f:1: OK\n", v / 100 + }' "/sys/block/zram$i/mm_stat" || ERR_CODE=-1 done } -- 2.35.3

2 years

1
1
0 0

[PATCH v4 00/12] RISCV: Add KVM_GET_REG_LIST API

by Haibo Xu

KVM_GET_REG_LIST will dump all register IDs that are available to KVM_GET/SET_ONE_REG and It's very useful to identify some platform regression issue during VM migration. Patch 1-7 re-structured the get-reg-list test in aarch64 to make some of the code as common test framework that can be shared by riscv. Patch 8 move reject_set check logic to a function so as to check for different errno for different registers. Patch 9 change to do the get/set operation only on present-blessed list. Patch 10 enabled the KVM_GET_REG_LIST API in riscv. patch 11-12 added the corresponding kselftest for checking possible register regressions. The get-reg-list kvm selftest was ported from aarch64 and tested with Linux 6.4-rc6 on a Qemu riscv64 virt machine. --- Changed since v3: * Rebase to Linux 6.4-rc6 * Address Andrew's suggestions and comments: * Move reject_set check logic to a function * Only do get/set tests on present blessed list * Only enable ISA extension for the specified config * For disable-not-allowed registers, move them to the filter-reg-list Andrew Jones (7): KVM: arm64: selftests: Replace str_with_index with strdup_printf KVM: arm64: selftests: Drop SVE cap check in print_reg KVM: arm64: selftests: Remove print_reg's dependency on vcpu_config KVM: arm64: selftests: Rename vcpu_config and add to kvm_util.h KVM: arm64: selftests: Delete core_reg_fixup KVM: arm64: selftests: Split get-reg-list test code KVM: arm64: selftests: Finish generalizing get-reg-list Haibo Xu (5): KVM: arm64: selftests: Move reject_set check logic to a function KVM: selftests: Only do get/set tests on present blessed list KVM: riscv: Add KVM_GET_REG_LIST API support KVM: riscv: selftests: Add finalize_vcpu check in run_test KVM: riscv: selftests: Add get-reg-list test Documentation/virt/kvm/api.rst | 2 +- arch/riscv/kvm/vcpu.c | 375 +++++++++ tools/testing/selftests/kvm/Makefile | 11 +- .../selftests/kvm/aarch64/get-reg-list.c | 538 ++----------- tools/testing/selftests/kvm/get-reg-list.c | 439 ++++++++++ .../selftests/kvm/include/kvm_util_base.h | 16 + .../selftests/kvm/include/riscv/processor.h | 3 + .../testing/selftests/kvm/include/test_util.h | 2 + tools/testing/selftests/kvm/lib/test_util.c | 15 + .../selftests/kvm/riscv/get-reg-list.c | 752 ++++++++++++++++++ 10 files changed, 1658 insertions(+), 495 deletions(-) create mode 100644 tools/testing/selftests/kvm/get-reg-list.c create mode 100644 tools/testing/selftests/kvm/riscv/get-reg-list.c -- 2.34.1

2 years

3
20
0 0

[PATCH v2] selftests/input: add tests for the EVIOCSABS ioctl

by Dana Elfassy

This patch introduces two tests for the EVIOCSABS ioctl. The first one checks that the ioctl fails when the EV_ABS bit was not set, and the second one just checks that the normal workflow for this ioctl succeeds. Signed-off-by: Dana Elfassy <dangel101(a)gmail.com> --- This patch depends on '[v3] selftests/input: Introduce basic tests for evdev ioctls' [1] sent to the ML. [1] https://patchwork.kernel.org/project/linux-input/patch/20230607153214.15933… tools/testing/selftests/input/evioc-test.c | 23 ++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/tools/testing/selftests/input/evioc-test.c b/tools/testing/selftests/input/evioc-test.c index 4c0c8ebed378..7afd537f0b24 100644 --- a/tools/testing/selftests/input/evioc-test.c +++ b/tools/testing/selftests/input/evioc-test.c @@ -279,4 +279,27 @@ TEST(eviocgrep_get_repeat_settings) selftest_uinput_destroy(uidev); } +TEST(eviocsabs_set_abs_value_limits) +{ + struct selftest_uinput *uidev; + struct input_absinfo absinfo; + int rc; + + // fail test on dev->absinfo + rc = selftest_uinput_create_device(&uidev), -1; + ASSERT_EQ(0, rc); + ASSERT_NE(NULL, uidev); + rc = ioctl(uidev->evdev_fd, EVIOCSABS(0), &absinfo); + ASSERT_EQ(-1, rc); + selftest_uinput_destroy(uidev); + + // ioctl normal flow + rc = selftest_uinput_create_device(&uidev, EV_ABS, -1); + ASSERT_EQ(0, rc); + ASSERT_NE(NULL, uidev); + rc = ioctl(uidev->evdev_fd, EVIOCSABS(0), &absinfo); + ASSERT_EQ(0, rc); + selftest_uinput_destroy(uidev); +} + TEST_HARNESS_MAIN -- 2.41.0

2 years

2
1
0 0

[PATCH v21 0/5] Implement IOCTL to get and optionally clear info about PTEs

by Muhammad Usama Anjum

Changes in v21: - Abort walk instead of returning error if WP is to be performed on partial hugetlb *Changes in v20* - Correct PAGE_IS_FILE and add PAGE_IS_PFNZERO *Changes in v19* - Minor changes and interface updates *Changes in v18* - Rebase on top of next-20230613 - Minor updates *Changes in v17* - Rebase on top of next-20230606 - Minor improvements in PAGEMAP_SCAN IOCTL patch *Changes in v16* - Fix a corner case - Add exclusive PM_SCAN_OP_WP back *Changes in v15* - Build fix (Add missed build fix in RESEND) *Changes in v14* - Fix build error caused by #ifdef added at last minute in some configs *Changes in v13* - Rebase on top of next-20230414 - Give-up on using uffd_wp_range() and write new helpers, flush tlb only once *Changes in v12* - Update and other memory types to UFFD_FEATURE_WP_ASYNC - Rebaase on top of next-20230406 - Review updates *Changes in v11* - Rebase on top of next-20230307 - Base patches on UFFD_FEATURE_WP_UNPOPULATED - Do a lot of cosmetic changes and review updates - Remove ENGAGE_WP + !GET operation as it can be performed with UFFDIO_WRITEPROTECT *Changes in v10* - Add specific condition to return error if hugetlb is used with wp async - Move changes in tools/include/uapi/linux/fs.h to separate patch - Add documentation *Changes in v9:* - Correct fault resolution for userfaultfd wp async - Fix build warnings and errors which were happening on some configs - Simplify pagemap ioctl's code *Changes in v8:* - Update uffd async wp implementation - Improve PAGEMAP_IOCTL implementation *Changes in v7:* - Add uffd wp async - Update the IOCTL to use uffd under the hood instead of soft-dirty flags *Motivation* The real motivation for adding PAGEMAP_SCAN IOCTL is to emulate Windows GetWriteWatch() syscall [1]. The GetWriteWatch{} retrieves the addresses of the pages that are written to in a region of virtual memory. This syscall is used in Windows applications and games etc. This syscall is being emulated in pretty slow manner in userspace. Our purpose is to enhance the kernel such that we translate it efficiently in a better way. Currently some out of tree hack patches are being used to efficiently emulate it in some kernels. We intend to replace those with these patches. So the whole gaming on Linux can effectively get benefit from this. It means there would be tons of users of this code. CRIU use case [2] was mentioned by Andrei and Danylo: > Use cases for migrating sparse VMAs are binaries sanitized with ASAN, > MSAN or TSAN [3]. All of these sanitizers produce sparse mappings of > shadow memory [4]. Being able to migrate such binaries allows to highly > reduce the amount of work needed to identify and fix post-migration > crashes, which happen constantly. Andrei's defines the following uses of this code: * it is more granular and allows us to track changed pages more effectively. The current interface can clear dirty bits for the entire process only. In addition, reading info about pages is a separate operation. It means we must freeze the process to read information about all its pages, reset dirty bits, only then we can start dumping pages. The information about pages becomes more and more outdated, while we are processing pages. The new interface solves both these downsides. First, it allows us to read pte bits and clear the soft-dirty bit atomically. It means that CRIU will not need to freeze processes to pre-dump their memory. Second, it clears soft-dirty bits for a specified region of memory. It means CRIU will have actual info about pages to the moment of dumping them. * The new interface has to be much faster because basic page filtering is happening in the kernel. With the old interface, we have to read pagemap for each page. *Implementation Evolution (Short Summary)* From the definition of GetWriteWatch(), we feel like kernel's soft-dirty feature can be used under the hood with some additions like: * reset soft-dirty flag for only a specific region of memory instead of clearing the flag for the entire process * get and clear soft-dirty flag for a specific region atomically So we decided to use ioctl on pagemap file to read or/and reset soft-dirty flag. But using soft-dirty flag, sometimes we get extra pages which weren't even written. They had become soft-dirty because of VMA merging and VM_SOFTDIRTY flag. This breaks the definition of GetWriteWatch(). We were able to by-pass this short coming by ignoring VM_SOFTDIRTY until David reported that mprotect etc messes up the soft-dirty flag while ignoring VM_SOFTDIRTY [5]. This wasn't happening until [6] got introduced. We discussed if we can revert these patches. But we could not reach to any conclusion. So at this point, I made couple of tries to solve this whole VM_SOFTDIRTY issue by correcting the soft-dirty implementation: * [7] Correct the bug fixed wrongly back in 2014. It had potential to cause regression. We left it behind. * [8] Keep a list of soft-dirty part of a VMA across splits and merges. I got the reply don't increase the size of the VMA by 8 bytes. At this point, we left soft-dirty considering it is too much delicate and userfaultfd [9] seemed like the only way forward. From there onward, we have been basing soft-dirty emulation on userfaultfd wp feature where kernel resolves the faults itself when WP_ASYNC feature is used. It was straight forward to add WP_ASYNC feature in userfautlfd. Now we get only those pages dirty or written-to which are really written in reality. (PS There is another WP_UNPOPULATED userfautfd feature is required which is needed to avoid pre-faulting memory before write-protecting [9].) All the different masks were added on the request of CRIU devs to create interface more generic and better. [1] https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-… [2] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com [3] https://github.com/google/sanitizers [4] https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm#64-bit [5] https://lore.kernel.org/all/bfcae708-db21-04b4-0bbe-712badd03071@redhat.com [6] https://lore.kernel.org/all/20220725142048.30450-1-peterx@redhat.com/ [7] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [8] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [9] https://lore.kernel.org/all/20230306213925.617814-1-peterx@redhat.com [10] https://lore.kernel.org/all/20230125144529.1630917-1-mdanylo@google.com * Original Cover letter from v8* Hello, Note: Soft-dirty pages and pages which have been written-to are synonyms. As kernel already has soft-dirty feature inside which we have given up to use, we are using written-to terminology while using UFFD async WP under the hood. This IOCTL, PAGEMAP_SCAN on pagemap file can be used to get and/or clear the info about page table entries. The following operations are supported in this ioctl: - Get the information if the pages have been written-to (PAGE_IS_WRITTEN), file mapped (PAGE_IS_FILE), present (PAGE_IS_PRESENT) or swapped (PAGE_IS_SWAPPED). - Write-protect the pages (PAGEMAP_WP_ENGAGE) to start finding which pages have been written-to. - Find pages which have been written-to and write protect the pages (atomic PAGE_IS_WRITTEN + PAGEMAP_WP_ENGAGE) It is possible to find and clear soft-dirty pages entirely in userspace. But it isn't efficient: - The mprotect and SIGSEGV handler for bookkeeping - The userfaultfd wp (synchronous) with the handler for bookkeeping Some benchmarks can be seen here[1]. This series adds features that weren't present earlier: - There is no atomic get soft-dirty/Written-to status and clear present in the kernel. - The pages which have been written-to can not be found in accurate way. (Kernel's soft-dirty PTE bit + sof_dirty VMA bit shows more soft-dirty pages than there actually are.) Historically, soft-dirty PTE bit tracking has been used in the CRIU project. The procfs interface is enough for finding the soft-dirty bit status and clearing the soft-dirty bit of all the pages of a process. We have the use case where we need to track the soft-dirty PTE bit for only specific pages on-demand. We need this tracking and clear mechanism of a region of memory while the process is running to emulate the getWriteWatch() syscall of Windows. *(Moved to using UFFD instead of soft-dirtyi feature to find pages which have been written-to from v7 patch series)*: Stop using the soft-dirty flags for finding which pages have been written to. It is too delicate and wrong as it shows more soft-dirty pages than the actual soft-dirty pages. There is no interest in correcting it [2][3] as this is how the feature was written years ago. It shouldn't be updated to changed behaviour. Peter Xu has suggested using the async version of the UFFD WP [4] as it is based inherently on the PTEs. So in this patch series, I've added a new mode to the UFFD which is asynchronous version of the write protect. When this variant of the UFFD WP is used, the page faults are resolved automatically by the kernel. The pages which have been written-to can be found by reading pagemap file (!PM_UFFD_WP). This feature can be used successfully to find which pages have been written to from the time the pages were write protected. This works just like the soft-dirty flag without showing any extra pages which aren't soft-dirty in reality. The information related to pages if the page is file mapped, present and swapped is required for the CRIU project [5][6]. The addition of the required mask, any mask, excluded mask and return masks are also required for the CRIU project [5]. The IOCTL returns the addresses of the pages which match the specific masks. The page addresses are returned in struct page_region in a compact form. The max_pages is needed to support a use case where user only wants to get a specific number of pages. So there is no need to find all the pages of interest in the range when max_pages is specified. The IOCTL returns when the maximum number of the pages are found. The max_pages is optional. If max_pages is specified, it must be equal or greater than the vec_size. This restriction is needed to handle worse case when one page_region only contains info of one page and it cannot be compacted. This is needed to emulate the Windows getWriteWatch() syscall. The patch series include the detailed selftest which can be used as an example for the uffd async wp test and PAGEMAP_IOCTL. It shows the interface usages as well. [1] https://lore.kernel.org/lkml/54d4c322-cd6e-eefd-b161-2af2b56aae24@collabora… [2] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [3] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [4] https://lore.kernel.org/all/Y6Hc2d+7eTKs7AiH@x1n [5] https://lore.kernel.org/all/YyiDg79flhWoMDZB@gmail.com/ [6] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com/ Regards, Muhammad Usama Anjum Muhammad Usama Anjum (4): fs/proc/task_mmu: Implement IOCTL to get and optionally clear info about PTEs tools headers UAPI: Update linux/fs.h with the kernel sources mm/pagemap: add documentation of PAGEMAP_SCAN IOCTL selftests: mm: add pagemap ioctl tests Peter Xu (1): userfaultfd: UFFD_FEATURE_WP_ASYNC Documentation/admin-guide/mm/pagemap.rst | 58 + Documentation/admin-guide/mm/userfaultfd.rst | 35 + fs/proc/task_mmu.c | 560 +++++++ fs/userfaultfd.c | 26 +- include/linux/hugetlb.h | 1 + include/linux/userfaultfd_k.h | 21 +- include/uapi/linux/fs.h | 54 + include/uapi/linux/userfaultfd.h | 9 +- mm/hugetlb.c | 34 +- mm/memory.c | 27 +- tools/include/uapi/linux/fs.h | 54 + tools/testing/selftests/mm/.gitignore | 2 + tools/testing/selftests/mm/Makefile | 3 +- tools/testing/selftests/mm/config | 1 + tools/testing/selftests/mm/pagemap_ioctl.c | 1464 ++++++++++++++++++ tools/testing/selftests/mm/run_vmtests.sh | 4 + 16 files changed, 2329 insertions(+), 24 deletions(-) create mode 100644 tools/testing/selftests/mm/pagemap_ioctl.c mode change 100644 => 100755 tools/testing/selftests/mm/run_vmtests.sh -- 2.39.2

2 years

3
13
0 0

[GIT PULL] Kselftest update for Linux 6.5-rc1

by Shuah Khan

Hi Linus, Please pull the following Kselftest update for Linux 6.5-rc1. This kselftest update for Linux 6.5-rc1 consists of: - change to allow runners to override the timeout This change is made to avoid future increases of long timeouts - several other spelling and cleanups - a new subtest to video_device_test - enhancements to test coverage in clone3 test - other fixes to ftrace and cpufreq tests diff is attached. thanks, -- Shuah ---------------------------------------------------------------- The following changes since commit 858fd168a95c5b9669aac8db6c14a9aeab446375: Linux 6.4-rc6 (2023-06-11 14:35:30 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest tags/linux-kselftest-next-6.5-rc1 for you to fetch changes up to 8cd0d8633e2de4e6dd9ddae7980432e726220fdb: selftests/ftace: Fix KTAP output ordering (2023-06-12 16:40:22 -0600) ---------------------------------------------------------------- linux-kselftest-next-6.5-rc1 This kselftest update for Linux 6.5-rc1 consists of: - change to allow runners to override the timeout This change is made to avoid future increases of long timeouts - several other spelling and cleanups - a new subtest to video_device_test - enhancements to test coverage in clone3 test - other fixes to ftrace and cpufreq tests ---------------------------------------------------------------- Akanksha J N (1): selftests/ftrace: Add new test case which checks for optimized probes Colin Ian King (2): selftests: prctl: Fix spelling mistake "anonynous" -> "anonymous" kselftest: vDSO: Fix accumulation of uninitialized ret when CLOCK_REALTIME is undefined Ivan Orlov (1): selftests: media_tests: Add new subtest to video_device_test Luis Chamberlain (1): selftests: allow runners to override the timeout Mark Brown (2): selftests/cpufreq: Don't enable generic lock debugging options selftests/ftace: Fix KTAP output ordering Rishabh Bhatnagar (1): kselftests: Sort the collections list to avoid duplicate tests Tobias Klauser (1): selftests/clone3: test clone3 with exit signal in flags Ziqi Zhao (1): selftest: pidfd: Omit long and repeating outputs Documentation/dev-tools/kselftest.rst | 22 ++++ tools/testing/selftests/clone3/clone3.c | 5 +- tools/testing/selftests/cpufreq/config | 8 -- tools/testing/selftests/ftrace/ftracetest | 2 +- .../ftrace/test.d/kprobe/kprobe_opt_types.tc | 34 +++++++ tools/testing/selftests/kselftest/runner.sh | 11 +- .../selftests/media_tests/video_device_test.c | 111 +++++++++++++++------ tools/testing/selftests/pidfd/pidfd.h | 1 - tools/testing/selftests/pidfd/pidfd_fdinfo_test.c | 1 + tools/testing/selftests/pidfd/pidfd_test.c | 3 +- .../selftests/prctl/set-anon-vma-name-test.c | 2 +- tools/testing/selftests/run_kselftest.sh | 7 +- .../selftests/vDSO/vdso_test_clock_getres.c | 4 +- 13 files changed, 166 insertions(+), 45 deletions(-) create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc ----------------------------------------------------------------

2 years

4
4
0 0

[PATCH 0/2] Restrict address space for sv39,sv48,sv57

by Charlie Jenkins

Make sv39 the default address space for mmap as some applications currently depend on this assumption. The RISC-V specification enforces that bits outside of the virtual address range are not used, so restricting the size of the default address space as such should be temporary. A hint address passed to mmap will cause the largest address space that fits entirely into the hint to be used. If the hint is less than or equal to 1<<38, a 39-bit address will be used. After an address space is completely full, the next smallest address space will be used. Documentation is also added to the RISC-V virtual memory section to explain these changes. Charlie Jenkins (2): RISC-V: mm: Restrict address space for sv39,sv48,sv57 RISC-V: mm: Update documentation and include test Documentation/riscv/vm-layout.rst | 20 ++++++++ arch/riscv/include/asm/elf.h | 2 +- arch/riscv/include/asm/pgtable.h | 21 ++++++-- arch/riscv/include/asm/processor.h | 41 +++++++++++++--- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/mm/Makefile | 22 +++++++++ .../selftests/riscv/mm/testcases/mmap.c | 49 +++++++++++++++++++ 7 files changed, 144 insertions(+), 13 deletions(-) create mode 100644 tools/testing/selftests/riscv/mm/Makefile create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap.c base-commit: eef509789cecdce895020682192d32e8bac790e8 -- 2.34.1

2 years

3
5
0 0

[PATCH v4 0/7] Optimize mremap during mutual alignment within PMD

by Joel Fernandes (Google)

Hello! Here is v4 of the mremap start address optimization / fix for exec warning. It took me a while to write a test that catches the issue me/Linus discussed in the last version. And I verified kernel crashes without the check. See below. The main changes in this series is: Care to be taken to move purely within a VMA, in other words this check in call_align_down(): if (vma->vm_start != addr_masked) return false; As an example of why this is needed: Consider the following range which is 2MB aligned and is a part of a larger 10MB range which is not shown. Each character is 256KB below making the source and destination 2MB each. The lower case letters are moved (s to d) and the upper case letters are not moved. |DDDDddddSSSSssss| If we align down 'ssss' to start from the 'SSSS', we will end up destroying SSSS. The above if statement prevents that and I verified it. I also added a test for this in the last patch. History of patches ================== v3->v4: 1. Make sure to check address to align is beginning of VMA 2. Add test to check this (test fails with a kernel crash if we don't do this). v2->v3: 1. Masked address was stored in int, fixed it to unsigned long to avoid truncation. 2. We now handle moves happening purely within a VMA, a new test is added to handle this. 3. More code comments. v1->v2: 1. Trigger the optimization for mremaps smaller than a PMD. I tested by tracing that it works correctly. 2. Fix issue with bogus return value found by Linus if we broke out of the above loop for the first PMD itself. v1: Initial RFC. Description of patches ====================== These patches optimizes the start addresses in move_page_tables() and tests the changes. It addresses a warning [1] that occurs due to a downward, overlapping move on a mutually-aligned offset within a PMD during exec. By initiating the copy process at the PMD level when such alignment is present, we can prevent this warning and speed up the copying process at the same time. Linus Torvalds suggested this idea. Please check the individual patches for more details. thanks, - Joel [1] https://lore.kernel.org/all/ZB2GTBD%2FLWTrkOiO@dhcp22.suse.cz/ Joel Fernandes (Google) (7): mm/mremap: Optimize the start addresses in move_page_tables() mm/mremap: Allow moves within the same VMA for stack selftests: mm: Fix failure case when new remap region was not found selftests: mm: Add a test for mutually aligned moves > PMD size selftests: mm: Add a test for remapping to area immediately after existing mapping selftests: mm: Add a test for remapping within a range selftests: mm: Add a test for moving from an offset from start of mapping fs/exec.c | 2 +- include/linux/mm.h | 2 +- mm/mremap.c | 63 ++++- tools/testing/selftests/mm/mremap_test.c | 301 +++++++++++++++++++---- 4 files changed, 319 insertions(+), 49 deletions(-) -- 2.41.0.rc2.161.g9c6817b8e7-goog

2 years

5
17
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-kselftest-mirror