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

[PATCH v4 0/3] selftests: cgroup: Enhance robustness with polling helpers

by Guopeng Zhang

Hi all, This patch series introduces improvements to the cgroup selftests by adding helper functions to better handle asynchronous updates in cgroup statistics. These changes are especially useful for managing cgroup stats like memory.stat and cgroup.stat, which can be affected by delays (e.g., RCPU callbacks and asynchronous rstat flushing). v4: - Patch 1/3: Adds the `cg_read_key_long_poll()` helper to poll cgroup keys with retries and configurable intervals. - Patch 2/3: Updates `test_memcg_sock()` to use `cg_read_key_long_poll()` for handling delayed "sock" counter updates in memory.stat. - Patch 3/3: Replaces `sleep` and retry logic in `test_kmem_dead_cgroups()` with `cg_read_key_long_poll()` for waiting on `nr_dying_descendants`. v3: - Move `MEMCG_SOCKSTAT_WAIT_*` defines after the `#include` block as suggested. v2: - Clarify the rationale for the 3s timeout and mention the periodic rstat flush interval (FLUSH_TIME = 2*HZ) in the comment. - Replace hardcoded retry count and wait interval with macros to avoid magic numbers and make the timeout calculation explicit. Thanks to Michal Koutný for the suggestion to introduce the polling helper, and to Lance Yang for the review. Guopeng Zhang (3): selftests: cgroup: Add cg_read_key_long_poll() to poll a cgroup key with retries selftests: cgroup: make test_memcg_sock robust against delayed sock stats selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on nr_dying_descendants .../selftests/cgroup/lib/cgroup_util.c | 21 +++++++++++++ .../cgroup/lib/include/cgroup_util.h | 5 +++ tools/testing/selftests/cgroup/test_kmem.c | 31 ++++++++----------- .../selftests/cgroup/test_memcontrol.c | 20 +++++++++++- 4 files changed, 58 insertions(+), 19 deletions(-) -- 2.25.1

4 days, 12 hours

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[PATCH] selftests: gpio: correctly check the type of /dev/gpiochipX

by Guixin Liu

/dev/gpiochipX is a character device, not a directory, so we should use "test -c" instead of "test -d" to check for its existence; otherwise, the current check will not work correctly when /dev/gpiochipX is left over (e.g., as a stale device node). Signed-off-by: Guixin Liu <kanie(a)linux.alibaba.com> --- tools/testing/selftests/gpio/gpio-aggregator.sh | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/gpio/gpio-aggregator.sh b/tools/testing/selftests/gpio/gpio-aggregator.sh index 9b6f80ad9f8a..13d8e1607571 100755 --- a/tools/testing/selftests/gpio/gpio-aggregator.sh +++ b/tools/testing/selftests/gpio/gpio-aggregator.sh @@ -351,7 +351,7 @@ test "$(agg_get_chip_num_lines _sysfs.0)" = "1" || fail "number of lines is not test "$(agg_get_line_name _sysfs.0 0)" = "" || fail "line name is unset" echo "$(agg_configfs_dev_name _sysfs.0)" > "$SYSFS_AGG_DIR/delete_device" test -d $CONFIGFS_AGG_DIR/_sysfs.0 && fail "_sysfs.0 unexpectedly remains" -test -d /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" +test -c /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" echo "1.2.2. Complex creation/deletion" echo "chip0bank0_0 chip1_bank1 10-11" > "$SYSFS_AGG_DIR/new_device" @@ -365,7 +365,7 @@ test "$(agg_get_line_name _sysfs.0 1)" = "" || fail "line name is unset" test "$(agg_get_line_name _sysfs.0 2)" = "" || fail "line name is unset" echo "$(agg_configfs_dev_name _sysfs.0)" > "$SYSFS_AGG_DIR/delete_device" test -d $CONFIGFS_AGG_DIR/_sysfs.0 && fail "_sysfs.0 unexpectedly remains" -test -d /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" +test -c /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" echo "1.2.3. Asynchronous creation with deferred probe" sim_disable_chip chip0 @@ -382,7 +382,7 @@ test "$(agg_get_chip_num_lines _sysfs.0)" = "1" || fail "number of lines is not test "$(agg_get_line_name _sysfs.0 0)" = "" || fail "line name unexpectedly set" echo "$(agg_configfs_dev_name _sysfs.0)" > "$SYSFS_AGG_DIR/delete_device" test -d $CONFIGFS_AGG_DIR/_sysfs.0 && fail "_sysfs.0 unexpectedly remains" -test -d /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" +test -c /dev/${CHIPNAME} && fail "/dev/${CHIPNAME} unexpectedly remains" echo "1.2.4. Can't instantiate a chip with invalid configuration" echo "xyz 0" > "$SYSFS_AGG_DIR/new_device" -- 2.43.0

4 days, 14 hours

1
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[RFC PATCH 0/3] Memory Controller eBPF support

by Hui Zhu

From: Hui Zhu <zhuhui(a)kylinos.cn> This series proposes adding eBPF support to the Linux memory controller, enabling dynamic and extensible memory management policies at runtime. Background The memory controller (memcg) currently provides fixed memory accounting and reclamation policies through static kernel code. This limits flexibility for specialized workloads and use cases that require custom memory management strategies. By enabling eBPF programs to hook into key memory control operations, administrators can implement custom policies without recompiling the kernel, while maintaining the safety guarantees provided by the BPF verifier. Use Cases 1. Custom memory reclamation strategies for specialized workloads 2. Dynamic memory pressure monitoring and telemetry 3. Memory accounting adjustments based on runtime conditions 4. Integration with container orchestration systems for intelligent resource management 5. Research and experimentation with novel memory management algorithms Design Overview This series introduces: 1. A new BPF struct ops type (`memcg_ops`) that allows eBPF programs to implement custom behavior for memory charging operations. 2. A hook point in the `try_charge_memcg()` fast path that invokes registered eBPF programs to determine if custom memory management should be applied. 3. The eBPF handler can inspect memory cgroup context and optionally modify certain parameters (e.g., `nr_pages` for reclamation size). 4. A reference counting mechanism using `percpu_ref` to safely manage the lifecycle of registered eBPF struct ops instances. 5. Configuration via `CONFIG_MEMCG_BPF` to allow disabling this feature at build time. Implementation Details - Uses BPF struct ops for a cleaner integration model - Leverages static branch keys for minimal overhead when feature is unused - RCU synchronization ensures safe replacement of handlers - Sample eBPF program demonstrates monitoring capabilities - Comprehensive selftest suite validates core functionality Performance Considerations - Zero overhead when feature is disabled or no eBPF program is loaded (static branch is disabled) - Minimal overhead when enabled: one indirect function call per charge attempt - eBPF programs run under the restrictions of the BPF verifier Patch Overview PATCH 1/3: Core kernel implementation - Adds eBPF struct ops support to memcg - Introduces CONFIG_MEMCG_BPF option - Implements safe registration/unregistration mechanism PATCH 2/3: Selftest suite - prog_tests/memcg_ops.c: Test entry points - progs/memcg_ops.bpf.c: Test eBPF program - Validates load, attach, and single-handler constraints PATCH 3/3: Sample userspace program - samples/bpf/memcg_printk.bpf.c: Monitoring eBPF program - samples/bpf/memcg_printk.c: Userspace loader - Demonstrates real-world usage and debugging capabilities Open Questions & Discussion Points 1. Should the eBPF handler have access to additional memory cgroup state? Current design exposes minimal context to reduce attack surface. 2. Are there other memory control operations that would benefit from eBPF extensibility (e.g., uncharge, reclaim)? 3. Should there be permission checks or restrictions on who can load memcg eBPF programs? Currently inherits BPF's CAP_PERFMON/CAP_SYS_ADMIN requirements. 4. How should we handle multiple eBPF programs trying to register? Current implementation allows only one active handler. 5. Is the current exposed context in `try_charge_memcg` struct sufficient, or should additional fields be added? Testing The selftests provide comprehensive coverage of the core functionality. The sample program can be used for manual testing and as a reference for implementing additional monitoring tools. Hui Zhu (3): memcg: add eBPF struct ops support for memory charging selftests/bpf: add memcg eBPF struct ops test samples/bpf: add example memcg eBPF program MAINTAINERS | 5 + init/Kconfig | 38 ++++ mm/Makefile | 1 + mm/memcontrol.c | 26 ++- mm/memcontrol_bpf.c | 200 ++++++++++++++++++ mm/memcontrol_bpf.h | 103 +++++++++ samples/bpf/Makefile | 2 + samples/bpf/memcg_printk.bpf.c | 30 +++ samples/bpf/memcg_printk.c | 82 +++++++ .../selftests/bpf/prog_tests/memcg_ops.c | 117 ++++++++++ tools/testing/selftests/bpf/progs/memcg_ops.c | 20 ++ 11 files changed, 617 insertions(+), 7 deletions(-) create mode 100644 mm/memcontrol_bpf.c create mode 100644 mm/memcontrol_bpf.h create mode 100644 samples/bpf/memcg_printk.bpf.c create mode 100644 samples/bpf/memcg_printk.c create mode 100644 tools/testing/selftests/bpf/prog_tests/memcg_ops.c create mode 100644 tools/testing/selftests/bpf/progs/memcg_ops.c -- 2.43.0

4 days, 14 hours

6
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[PATCH] selftests/mm/uffd: initialize char variable to Null

by Ankit Khushwaha

In "uffd-stress.c" & "uffd-unit-tests.c". address of char variable having garbage value (uninitialized) is passed to 'write' syscall triggers warning. uffd-stress.c:246:39: warning: variable 'c' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer] uffd-unit-tests.c:581:31: warning: variable 'c' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer] so the fix is to assign char variable to '\0' to prevent writing of garbage value. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- this warning is raised with clang version 21.1.5 (Fedora 21.1.5-1.fc43). --- tools/testing/selftests/mm/uffd-stress.c | 2 +- tools/testing/selftests/mm/uffd-unit-tests.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c index b51c89e1cd1a..700fbaa18d44 100644 --- a/tools/testing/selftests/mm/uffd-stress.c +++ b/tools/testing/selftests/mm/uffd-stress.c @@ -241,7 +241,7 @@ static int stress(struct uffd_args *args) return 1; for (cpu = 0; cpu < gopts->nr_parallel; cpu++) { - char c; + char c = '\0'; if (bounces & BOUNCE_POLL) { if (write(gopts->pipefd[cpu*2+1], &c, 1) != 1) err("pipefd write error"); diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c index f917b4c4c943..f4807242c5b2 100644 --- a/tools/testing/selftests/mm/uffd-unit-tests.c +++ b/tools/testing/selftests/mm/uffd-unit-tests.c @@ -543,7 +543,7 @@ static void uffd_minor_test_common(uffd_global_test_opts_t *gopts, bool test_col { unsigned long p; pthread_t uffd_mon; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -759,7 +759,7 @@ static void uffd_sigbus_test_common(uffd_global_test_opts_t *gopts, bool wp) pthread_t uffd_mon; pid_t pid; int err; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -819,7 +819,7 @@ static void uffd_events_test_common(uffd_global_test_opts_t *gopts, bool wp) pthread_t uffd_mon; pid_t pid; int err; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -1125,7 +1125,7 @@ uffd_move_test_common(uffd_global_test_opts_t *gopts, { unsigned long nr; pthread_t uffd_mon; - char c; + char c = '\0'; unsigned long long count; struct uffd_args args = { 0 }; char *orig_area_src = NULL, *orig_area_dst = NULL; -- 2.52.0

4 days, 18 hours

2
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[PATCH] [PATCH v4] selftests/seccomp: Fix indentation and rebase error logging patch

by Sameeksha Sankpal

v4: - Resending v3 after reviewer feedback (Shuah Khan). - No code changes. - Fixes email formatting and broken threading in earlier versions. v3: - Rebased against upstream seccomp tree. - Fixed indentation to use tabs instead of spaces. - Used scripts/checkpatch.pl to fix warnings. - Removed blank line before Signed-off-by. v2: - Used TH_LOG instead of printf for error logging. - Moved variable declaration to the top of the function. - Applied review suggestions from Kees Cook. v1: - Initial patch to improve error logging in get_proc_stat(). Suggested-by: Kees Cook <kees(a)kernel.org> Signed-off-by: Sameeksha Sankpal <sameekshasankpal(a)gmail.com> --- tools/testing/selftests/seccomp/seccomp_bpf.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index 61acbd45ffaa..dbd7e705a2af 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -4508,9 +4508,14 @@ static char get_proc_stat(struct __test_metadata *_metadata, pid_t pid) char proc_path[100] = {0}; char status; char *line; + int rc; snprintf(proc_path, sizeof(proc_path), "/proc/%d/stat", pid); ASSERT_EQ(get_nth(_metadata, proc_path, 3, &line), 1); + rc = get_nth(_metadata, proc_path, 3, &line); + ASSERT_EQ(rc, 1) { + TH_LOG("user_notification_fifo: failed to read stat for PID %d (rc=%d)", pid, rc); + } status = *line; free(line); -- 2.43.0

4 days, 20 hours

1
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[PATCH net-next v2] selftests/net: initialize char variable to null

by Ankit Khushwaha

char variable in 'so_txtime.c' & 'txtimestamp.c' were left uninitilized when switch default case taken. which raises following warning. txtimestamp.c:240:2: warning: variable 'tsname' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized] so_txtime.c:210:3: warning: variable 'reason' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized] initializing these variables to NULL to fix this. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- changelog: v2: change patch name to net-next. v1: https://lore.kernel.org/all/20251124161324.16901-1-ankitkhushwaha.linux@gma… --- tools/testing/selftests/net/so_txtime.c | 2 +- tools/testing/selftests/net/txtimestamp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/so_txtime.c b/tools/testing/selftests/net/so_txtime.c index 8457b7ccbc09..b76df1efc2ef 100644 --- a/tools/testing/selftests/net/so_txtime.c +++ b/tools/testing/selftests/net/so_txtime.c @@ -174,7 +174,7 @@ static int do_recv_errqueue_timeout(int fdt) msg.msg_controllen = sizeof(control); while (1) { - const char *reason; + const char *reason = NULL; ret = recvmsg(fdt, &msg, MSG_ERRQUEUE); if (ret == -1 && errno == EAGAIN) diff --git a/tools/testing/selftests/net/txtimestamp.c b/tools/testing/selftests/net/txtimestamp.c index dae91eb97d69..bcc14688661d 100644 --- a/tools/testing/selftests/net/txtimestamp.c +++ b/tools/testing/selftests/net/txtimestamp.c @@ -217,7 +217,7 @@ static void print_timestamp_usr(void) static void print_timestamp(struct scm_timestamping *tss, int tstype, int tskey, int payload_len) { - const char *tsname; + const char *tsname = NULL; validate_key(tskey, tstype); -- 2.52.0

4 days, 23 hours

3
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[PATCH bpf-next v12 0/7] bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags for percpu maps

by Leon Hwang

This patch set introduces the BPF_F_CPU and BPF_F_ALL_CPUS flags for percpu maps, as the requirement of BPF_F_ALL_CPUS flag for percpu_array maps was discussed in the thread of "[PATCH bpf-next v3 0/4] bpf: Introduce global percpu data"[1]. The goal of BPF_F_ALL_CPUS flag is to reduce data caching overhead in light skeletons by allowing a single value to be reused to update values across all CPUs. This avoids the M:N problem where M cached values are used to update a map on N CPUs kernel. The BPF_F_CPU flag is accompanied by *flags*-embedded cpu info, which specifies the target CPU for the operation: * For lookup operations: the flag field alongside cpu info enable querying a value on the specified CPU. * For update operations: the flag field alongside cpu info enable updating value for specified CPU. Links: [1] https://lore.kernel.org/bpf/20250526162146.24429-1-leon.hwang@linux.dev/ Changes: v11 -> v12: * Dropped the v11 changes. * Stabilized the lru_percpu_hash map test by keeping an extra spare entry, which can be used temporarily during updates to avoid unintended LRU evictions. v10 -> v11: * Support the combination of BPF_EXIST and BPF_F_CPU/BPF_F_ALL_CPUS for update operations. * Fix unstable lru_percpu_hash map test using the combination of BPF_EXIST and BPF_F_CPU/BPF_F_ALL_CPUS to avoid LRU eviction (reported by Alexei). v9 -> v10: * Add tests to verify array and hash maps do not support BPF_F_CPU and BPF_F_ALL_CPUS flags. * Address comment from Andrii: * Copy map value using copy_map_value_long for percpu_cgroup_storage maps in a separate patch. v8 -> v9: * Change value type from u64 to u32 in selftests. * Address comments from Andrii: * Keep value_size unaligned and update everywhere for consistency when cpu flags are specified. * Update value by getting pointer for percpu hash and percpu cgroup_storage maps. v7 -> v8: * Address comments from Andrii: * Check BPF_F_LOCK when update percpu_array, percpu_hash and lru_percpu_hash maps. * Refactor flags check in __htab_map_lookup_and_delete_batch(). * Keep value_size unaligned and copy value using copy_map_value() in __htab_map_lookup_and_delete_batch() when BPF_F_CPU is specified. * Update warn message in libbpf's validate_map_op(). * Update comment of libbpf's bpf_map__lookup_elem(). v6 -> v7: * Get correct value size for percpu_hash and lru_percpu_hash in update_batch API. * Set 'count' as 'max_entries' in test cases for lookup_batch API. * Address comment from Alexei: * Move cpu flags check into bpf_map_check_op_flags(). v5 -> v6: * Move bpf_map_check_op_flags() from 'bpf.h' to 'syscall.c'. * Address comments from Alexei: * Drop the refactoring code of data copying logic for percpu maps. * Drop bpf_map_check_op_flags() wrappers. v4 -> v5: * Address comments from Andrii: * Refactor data copying logic for all percpu maps. * Drop this_cpu_ptr() micro-optimization. * Drop cpu check in libbpf's validate_map_op(). * Enhance bpf_map_check_op_flags() using *allowed flags* instead of 'extra_flags_mask'. v3 -> v4: * Address comments from Andrii: * Remove unnecessary map_type check in bpf_map_value_size(). * Reduce code churn. * Remove unnecessary do_delete check in __htab_map_lookup_and_delete_batch(). * Introduce bpf_percpu_copy_to_user() and bpf_percpu_copy_from_user(). * Rename check_map_flags() to bpf_map_check_op_flags() with extra_flags_mask. * Add human-readable pr_warn() explanations in validate_map_op(). * Use flags in bpf_map__delete_elem() and bpf_map__lookup_and_delete_elem(). * Drop "for alignment reasons". v3 link: https://lore.kernel.org/bpf/20250821160817.70285-1-leon.hwang@linux.dev/ v2 -> v3: * Address comments from Alexei: * Use BPF_F_ALL_CPUS instead of BPF_ALL_CPUS magic. * Introduce these two cpu flags for all percpu maps. * Address comments from Jiri: * Reduce some unnecessary u32 cast. * Refactor more generic map flags check function. * A code style issue. v2 link: https://lore.kernel.org/bpf/20250805163017.17015-1-leon.hwang@linux.dev/ v1 -> v2: * Address comments from Andrii: * Embed cpu info as high 32 bits of *flags* totally. * Use ERANGE instead of E2BIG. * Few format issues. Leon Hwang (7): bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_array maps bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_hash and lru_percpu_hash maps bpf: Copy map value using copy_map_value_long for percpu_cgroup_storage maps bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_cgroup_storage maps libbpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu maps selftests/bpf: Add cases to test BPF_F_CPU and BPF_F_ALL_CPUS flags include/linux/bpf-cgroup.h | 4 +- include/linux/bpf.h | 35 +- include/uapi/linux/bpf.h | 2 + kernel/bpf/arraymap.c | 29 +- kernel/bpf/hashtab.c | 94 +++-- kernel/bpf/local_storage.c | 27 +- kernel/bpf/syscall.c | 37 +- tools/include/uapi/linux/bpf.h | 2 + tools/lib/bpf/bpf.h | 8 + tools/lib/bpf/libbpf.c | 26 +- tools/lib/bpf/libbpf.h | 21 +- .../selftests/bpf/prog_tests/percpu_alloc.c | 328 ++++++++++++++++++ .../selftests/bpf/progs/percpu_alloc_array.c | 32 ++ 13 files changed, 560 insertions(+), 85 deletions(-) -- 2.51.2

5 days, 1 hour

4
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[PATCH net-next v6 0/5] netconsole: support automatic target recovery

by Andre Carvalho

This patchset introduces target resume capability to netconsole allowing it to recover targets when underlying low-level interface comes back online. The patchset starts by refactoring netconsole state representation in order to allow representing deactivated targets (targets that are disabled due to interfaces going down). It then modifies netconsole to handle NETDEV_UP events for such targets and setups netpoll. Targets are matched with incoming interfaces depending on how they were initially bound in netconsole (by mac or interface name). The patchset includes a selftest that validates netconsole target state transitions and that target is functional after resumed. Signed-off-by: Andre Carvalho <asantostc(a)gmail.com> --- Changes in v6: - Rebase on top of net-next to resolve conflicts, no functional changes. - Link to v5: https://lore.kernel.org/r/20251119-netcons-retrigger-v5-0-2c7dda6055d6@gmai… Changes in v5: - patch 3: Set (de)enslaved target as DISABLED instead of DEACTIVATED to prevent resuming it. - selftest: Fix test cleanup by moving trap line to outside of loop and remove unneeded 'local' keyword - Rename maybe_resume_target to resume_target, add netconsole_ prefix to process_resumable_targets. - Hold device reference before calling __netpoll_setup. - Link to v4: https://lore.kernel.org/r/20251116-netcons-retrigger-v4-0-5290b5f140c2@gmai… Changes in v4: - Simplify selftest cleanup, removing trap setup in loop. - Drop netpoll helper (__setup_netpoll_hold) and manage reference inside netconsole. - Move resume_list processing logic to separate function. - Link to v3: https://lore.kernel.org/r/20251109-netcons-retrigger-v3-0-1654c280bbe6@gmai… Changes in v3: - Resume by mac or interface name depending on how target was created. - Attempt to resume target without holding target list lock, by moving the target to a temporary list. This is required as netpoll may attempt to allocate memory. - Link to v2: https://lore.kernel.org/r/20250921-netcons-retrigger-v2-0-a0e84006237f@gmai… Changes in v2: - Attempt to resume target in the same thread, instead of using workqueue . - Add wrapper around __netpoll_setup (patch 4). - Renamed resume_target to maybe_resume_target and moved conditionals to inside its implementation, keeping code more clear. - Verify that device addr matches target mac address when target was setup using mac. - Update selftest to cover targets bound by mac and interface name. - Fix typo in selftest comment and sort tests alphabetically in Makefile. - Link to v1: https://lore.kernel.org/r/20250909-netcons-retrigger-v1-0-3aea904926cf@gmai… --- Andre Carvalho (3): netconsole: convert 'enabled' flag to enum for clearer state management netconsole: resume previously deactivated target selftests: netconsole: validate target resume Breno Leitao (2): netconsole: add target_state enum netconsole: add STATE_DEACTIVATED to track targets disabled by low level drivers/net/netconsole.c | 155 +++++++++++++++++---- tools/testing/selftests/drivers/net/Makefile | 1 + .../selftests/drivers/net/lib/sh/lib_netcons.sh | 35 ++++- .../selftests/drivers/net/netcons_resume.sh | 97 +++++++++++++ 4 files changed, 254 insertions(+), 34 deletions(-) --- base-commit: e2c20036a8879476c88002730d8a27f4e3c32d4b change-id: 20250816-netcons-retrigger-a4f547bfc867 Best regards, -- Andre Carvalho <asantostc(a)gmail.com>

5 days, 3 hours

2
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[PATCH v2 0/9] Initial DMABUF support for iommufd

by Jason Gunthorpe

This series is the start of adding full DMABUF support to iommufd. Currently it is limited to only work with VFIO's DMABUF exporter. It sits on top of Leon's series to add a DMABUF exporter to VFIO: https://lore.kernel.org/all/20251120-dmabuf-vfio-v9-0-d7f71607f371@nvidia.c… The existing IOMMU_IOAS_MAP_FILE is enhanced to detect DMABUF fd's, but otherwise works the same as it does today for a memfd. The user can select a slice of the FD to map into the ioas and if the underliyng alignment requirements are met it will be placed in the iommu_domain. Though limited, it is enough to allow a VMM like QEMU to connect MMIO BAR memory from VFIO to an iommu_domain controlled by iommufd. This is used for PCI Peer to Peer support in VMs, and is the last feature that the VFIO type 1 container has that iommufd couldn't do. The VFIO type1 version extracts raw PFNs from VMAs, which has no lifetime control and is a use-after-free security problem. Instead iommufd relies on revokable DMABUFs. Whenever VFIO thinks there should be no access to the MMIO it can shoot down the mapping in iommufd which will unmap it from the iommu_domain. There is no automatic remap, this is a safety protocol so the kernel doesn't get stuck. Userspace is expected to know it is doing something that will revoke the dmabuf and map/unmap it around the activity. Eg when QEMU goes to issue FLR it should do the map/unmap to iommufd. Since DMABUF is missing some key general features for this use case it relies on a "private interconnect" between VFIO and iommufd via the vfio_pci_dma_buf_iommufd_map() call. The call confirms the DMABUF has revoke semantics and delivers a phys_addr for the memory suitable for use with iommu_map(). Medium term there is a desire to expand the supported DMABUFs to include GPU drivers to support DPDK/SPDK type use cases so future series will work to add a general concept of revoke and a general negotiation of interconnect to remove vfio_pci_dma_buf_iommufd_map(). I also plan another series to modify iommufd's vfio_compat to transparently pull a dmabuf out of a VFIO VMA to emulate more of the uAPI of type1. The latest series for interconnect negotation to exchange a phys_addr is: https://lore.kernel.org/r/20251027044712.1676175-1-vivek.kasireddy@intel.com And the discussion for design of revoke is here: https://lore.kernel.org/dri-devel/20250114173103.GE5556@nvidia.com/ This is on github: https://github.com/jgunthorpe/linux/commits/iommufd_dmabuf v2: - Rebase on Leon's v9 - Fix mislocking in an iopt_fill_domain() error path - Revise the comments around how the sub page offset works - Remove a useless WARN_ON in iopt_pages_rw_access() - Fixed missed memory free in the selftest v1: https://patch.msgid.link/r/0-v1-64bed2430cdb+31b-iommufd_dmabuf_jgg@nvidia.… Jason Gunthorpe (9): vfio/pci: Add vfio_pci_dma_buf_iommufd_map() iommufd: Add DMABUF to iopt_pages iommufd: Do not map/unmap revoked DMABUFs iommufd: Allow a DMABUF to be revoked iommufd: Allow MMIO pages in a batch iommufd: Have pfn_reader process DMABUF iopt_pages iommufd: Have iopt_map_file_pages convert the fd to a file iommufd: Accept a DMABUF through IOMMU_IOAS_MAP_FILE iommufd/selftest: Add some tests for the dmabuf flow drivers/iommu/iommufd/io_pagetable.c | 78 +++- drivers/iommu/iommufd/io_pagetable.h | 54 ++- drivers/iommu/iommufd/ioas.c | 8 +- drivers/iommu/iommufd/iommufd_private.h | 14 +- drivers/iommu/iommufd/iommufd_test.h | 10 + drivers/iommu/iommufd/main.c | 10 + drivers/iommu/iommufd/pages.c | 414 ++++++++++++++++-- drivers/iommu/iommufd/selftest.c | 143 ++++++ drivers/vfio/pci/vfio_pci_dmabuf.c | 34 ++ include/linux/vfio_pci_core.h | 4 + tools/testing/selftests/iommu/iommufd.c | 43 ++ tools/testing/selftests/iommu/iommufd_utils.h | 44 ++ 12 files changed, 786 insertions(+), 70 deletions(-) base-commit: f836737ed56db9e2d5b047c56a31e05af0f3f116 -- 2.43.0

5 days, 5 hours

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[PATCH] 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> --- 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 b1fc9b916ace..cad7da1bd7ca 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: ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d change-id: 20251126-selftests-filesystems-devpts-tiocgptpeer-fbd30e579859 Best regards, -- Mark Brown <broonie(a)kernel.org>

5 days, 5 hours

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