October 2021 - Linux-kselftest-mirror

[PATCH v4 00/10] Add support for synchronous signals on perf events

by Marco Elver

The perf subsystem today unifies various tracing and monitoring features, from both software and hardware. One benefit of the perf subsystem is automatically inheriting events to child tasks, which enables process-wide events monitoring with low overheads. By default perf events are non-intrusive, not affecting behaviour of the tasks being monitored. For certain use-cases, however, it makes sense to leverage the generality of the perf events subsystem and optionally allow the tasks being monitored to receive signals on events they are interested in. This patch series adds the option to synchronously signal user space on events. To better support process-wide synchronous self-monitoring, without events propagating to children that do not share the current process's shared environment, two pre-requisite patches are added to optionally restrict inheritance to CLONE_THREAD, and remove events on exec (without affecting the parent). Examples how to use these features can be found in the tests added at the end of the series. In addition to the tests added, the series has also been subjected to syzkaller fuzzing (focus on 'kernel/events/' coverage). Motivation and Example Uses --------------------------- 1. Our immediate motivation is low-overhead sampling-based race detection for user space [1]. By using perf_event_open() at process initialization, we can create hardware breakpoint/watchpoint events that are propagated automatically to all threads in a process. As far as we are aware, today no existing kernel facility (such as ptrace) allows us to set up process-wide watchpoints with minimal overheads (that are comparable to mprotect() of whole pages). 2. Other low-overhead error detectors that rely on detecting accesses to certain memory locations or code, process-wide and also only in a specific set of subtasks or threads. [1] https://llvm.org/devmtg/2020-09/slides/Morehouse-GWP-Tsan.pdf Other ideas for use-cases we found interesting, but should only illustrate the range of potential to further motivate the utility (we're sure there are more): 3. Code hot patching without full stop-the-world. Specifically, by setting a code breakpoint to entry to the patched routine, then send signals to threads and check that they are not in the routine, but without stopping them further. If any of the threads will enter the routine, it will receive SIGTRAP and pause. 4. Safepoints without mprotect(). Some Java implementations use "load from a known memory location" as a safepoint. When threads need to be stopped, the page containing the location is mprotect()ed and threads get a signal. This could be replaced with a watchpoint, which does not require a whole page nor DTLB shootdowns. 5. Threads receiving signals on performance events to throttle/unthrottle themselves. 6. Tracking data flow globally. Changelog --------- v4: * Fix for parent and child racing to exit in sync_child_event(). * Fix race between irq_work running and task's sighand being released by release_task(). * Generalize setting si_perf and si_addr independent of event type; introduces perf_event_attr::sig_data, which can be set by user space to be propagated to si_perf. * Warning in perf_sigtrap() if ctx->task and current mismatch; we expect this on architectures that do not properly implement arch_irq_work_raise(). * Require events that want sigtrap to be associated with a task. * Dropped "perf: Add breakpoint information to siginfo on SIGTRAP" in favor of more generic solution (perf_event_attr::sig_data). v3: * Add patch "perf: Rework perf_event_exit_event()" to beginning of series, courtesy of Peter Zijlstra. * Rework "perf: Add support for event removal on exec" based on the added "perf: Rework perf_event_exit_event()". * Fix kselftests to work with more recent libc, due to the way it forces using the kernel's own siginfo_t. * Add basic perf-tool built-in test. v2/RFC: https://lkml.kernel.org/r/20210310104139.679618-1-elver@google.com * Patch "Support only inheriting events if cloned with CLONE_THREAD" added to series. * Patch "Add support for event removal on exec" added to series. * Patch "Add kselftest for process-wide sigtrap handling" added to series. * Patch "Add kselftest for remove_on_exec" added to series. * Implicitly restrict inheriting events if sigtrap, but the child was cloned with CLONE_CLEAR_SIGHAND, because it is not generally safe if the child cleared all signal handlers to continue sending SIGTRAP. * Various minor fixes (see details in patches). v1/RFC: https://lkml.kernel.org/r/20210223143426.2412737-1-elver@google.com Pre-series: The discussion at [2] led to the changes in this series. The approach taken in "Add support for SIGTRAP on perf events" to trigger the signal was suggested by Peter Zijlstra in [3]. [2] https://lore.kernel.org/lkml/CACT4Y+YPrXGw+AtESxAgPyZ84TYkNZdP0xpocX2jwVAbZ… [3] https://lore.kernel.org/lkml/YBv3rAT566k+6zjg@hirez.programming.kicks-ass.n… Marco Elver (9): perf: Apply PERF_EVENT_IOC_MODIFY_ATTRIBUTES to children perf: Support only inheriting events if cloned with CLONE_THREAD perf: Add support for event removal on exec signal: Introduce TRAP_PERF si_code and si_perf to siginfo perf: Add support for SIGTRAP on perf events selftests/perf_events: Add kselftest for process-wide sigtrap handling selftests/perf_events: Add kselftest for remove_on_exec tools headers uapi: Sync tools/include/uapi/linux/perf_event.h perf test: Add basic stress test for sigtrap handling Peter Zijlstra (1): perf: Rework perf_event_exit_event() arch/m68k/kernel/signal.c | 3 + arch/x86/kernel/signal_compat.c | 5 +- fs/signalfd.c | 4 + include/linux/compat.h | 2 + include/linux/perf_event.h | 9 +- include/linux/signal.h | 1 + include/uapi/asm-generic/siginfo.h | 6 +- include/uapi/linux/perf_event.h | 12 +- include/uapi/linux/signalfd.h | 4 +- kernel/events/core.c | 302 +++++++++++++----- kernel/fork.c | 2 +- kernel/signal.c | 11 + tools/include/uapi/linux/perf_event.h | 12 +- tools/perf/tests/Build | 1 + tools/perf/tests/builtin-test.c | 5 + tools/perf/tests/sigtrap.c | 150 +++++++++ tools/perf/tests/tests.h | 1 + .../testing/selftests/perf_events/.gitignore | 3 + tools/testing/selftests/perf_events/Makefile | 6 + tools/testing/selftests/perf_events/config | 1 + .../selftests/perf_events/remove_on_exec.c | 260 +++++++++++++++ tools/testing/selftests/perf_events/settings | 1 + .../selftests/perf_events/sigtrap_threads.c | 210 ++++++++++++ 23 files changed, 924 insertions(+), 87 deletions(-) create mode 100644 tools/perf/tests/sigtrap.c create mode 100644 tools/testing/selftests/perf_events/.gitignore create mode 100644 tools/testing/selftests/perf_events/Makefile create mode 100644 tools/testing/selftests/perf_events/config create mode 100644 tools/testing/selftests/perf_events/remove_on_exec.c create mode 100644 tools/testing/selftests/perf_events/settings create mode 100644 tools/testing/selftests/perf_events/sigtrap_threads.c -- 2.31.0.208.g409f899ff0-goog

1 month, 2 weeks

5
29
0 0

[PATCH v6] lib: add basic KUnit test for lib/math

by Daniel Latypov

Add basic test coverage for files that don't require any config options: * part of math.h (what seem to be the most commonly used macros) * gcd.c * lcm.c * int_sqrt.c * reciprocal_div.c (Ignored int_pow.c since it's a simple textbook algorithm.) These tests aren't particularly interesting, but they * provide short and simple examples of parameterized tests * provide a place to add tests for any new files in this dir * are written so adding new test cases to cover edge cases should be easy * looking at code coverage, we hit all the branches in the .c files Signed-off-by: Daniel Latypov <dlatypov(a)google.com> Reviewed-by: David Gow <davidgow(a)google.com> --- Changes since v5: * add in test cases for roundup/rounddown * address misc comments from David Changes since v4: * add in test cases for some math.h macros (abs, round_up/round_down, div_round_down/closest) * use parameterized testing less to keep things terser Changes since v3: * fix `checkpatch.pl --strict` warnings * add test cases for gcd(0,0) and lcm(0,0) * minor: don't test both gcd(a,b) and gcd(b,a) when a == b Changes since v2: mv math_test.c => math_kunit.c Changes since v1: * Rebase and rewrite to use the new parameterized testing support. * misc: fix overflow in literal and inline int_sqrt format string. * related: commit 1f0e943df68a ("Documentation: kunit: provide guidance for testing many inputs") was merged explaining the patterns shown here. * there's an in-flight patch to update it for parameterized testing. --- lib/math/Kconfig | 12 ++ lib/math/Makefile | 2 + lib/math/math_kunit.c | 291 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 305 insertions(+) create mode 100644 lib/math/math_kunit.c diff --git a/lib/math/Kconfig b/lib/math/Kconfig index f19bc9734fa7..a974d4db0f9c 100644 --- a/lib/math/Kconfig +++ b/lib/math/Kconfig @@ -15,3 +15,15 @@ config PRIME_NUMBERS config RATIONAL bool + +config MATH_KUNIT_TEST + tristate "KUnit test for lib/math and math.h" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds unit tests for lib/math and math.h. + + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. diff --git a/lib/math/Makefile b/lib/math/Makefile index be6909e943bd..30abb7a8d564 100644 --- a/lib/math/Makefile +++ b/lib/math/Makefile @@ -4,3 +4,5 @@ obj-y += div64.o gcd.o lcm.o int_pow.o int_sqrt.o reciprocal_div.o obj-$(CONFIG_CORDIC) += cordic.o obj-$(CONFIG_PRIME_NUMBERS) += prime_numbers.o obj-$(CONFIG_RATIONAL) += rational.o + +obj-$(CONFIG_MATH_KUNIT_TEST) += math_kunit.o diff --git a/lib/math/math_kunit.c b/lib/math/math_kunit.c new file mode 100644 index 000000000000..556c23b17c3c --- /dev/null +++ b/lib/math/math_kunit.c @@ -0,0 +1,291 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Simple KUnit suite for math helper funcs that are always enabled. + * + * Copyright (C) 2020, Google LLC. + * Author: Daniel Latypov <dlatypov(a)google.com> + */ + +#include <kunit/test.h> +#include <linux/gcd.h> +#include <linux/kernel.h> +#include <linux/lcm.h> +#include <linux/reciprocal_div.h> + +static void abs_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, abs((char)0), (char)0); + KUNIT_EXPECT_EQ(test, abs((char)42), (char)42); + KUNIT_EXPECT_EQ(test, abs((char)-42), (char)42); + + /* The expression in the macro is actually promoted to an int. */ + KUNIT_EXPECT_EQ(test, abs((short)0), 0); + KUNIT_EXPECT_EQ(test, abs((short)42), 42); + KUNIT_EXPECT_EQ(test, abs((short)-42), 42); + + KUNIT_EXPECT_EQ(test, abs(0), 0); + KUNIT_EXPECT_EQ(test, abs(42), 42); + KUNIT_EXPECT_EQ(test, abs(-42), 42); + + KUNIT_EXPECT_EQ(test, abs(0L), 0L); + KUNIT_EXPECT_EQ(test, abs(42L), 42L); + KUNIT_EXPECT_EQ(test, abs(-42L), 42L); + + KUNIT_EXPECT_EQ(test, abs(0LL), 0LL); + KUNIT_EXPECT_EQ(test, abs(42LL), 42LL); + KUNIT_EXPECT_EQ(test, abs(-42LL), 42LL); + + /* Unsigned types get casted to signed. */ + KUNIT_EXPECT_EQ(test, abs(0ULL), 0LL); + KUNIT_EXPECT_EQ(test, abs(42ULL), 42LL); +} + +static void int_sqrt_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, int_sqrt(0UL), 0UL); + KUNIT_EXPECT_EQ(test, int_sqrt(1UL), 1UL); + KUNIT_EXPECT_EQ(test, int_sqrt(4UL), 2UL); + KUNIT_EXPECT_EQ(test, int_sqrt(5UL), 2UL); + KUNIT_EXPECT_EQ(test, int_sqrt(8UL), 2UL); + KUNIT_EXPECT_EQ(test, int_sqrt(1UL << 30), 1UL << 15); +} + +static void round_up_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, round_up(0, 1), 0); + KUNIT_EXPECT_EQ(test, round_up(1, 2), 2); + KUNIT_EXPECT_EQ(test, round_up(3, 2), 4); + KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 2), 1 << 30); + KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 1 << 29), 1 << 30); +} + +static void round_down_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, round_down(0, 1), 0); + KUNIT_EXPECT_EQ(test, round_down(1, 2), 0); + KUNIT_EXPECT_EQ(test, round_down(3, 2), 2); + KUNIT_EXPECT_EQ(test, round_down((1 << 30) - 1, 2), (1 << 30) - 2); + KUNIT_EXPECT_EQ(test, round_down((1 << 30) - 1, 1 << 29), 1 << 29); +} + +/* These versions can round to numbers that aren't a power of two */ +static void roundup_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, roundup(0, 1), 0); + KUNIT_EXPECT_EQ(test, roundup(1, 2), 2); + KUNIT_EXPECT_EQ(test, roundup(3, 2), 4); + KUNIT_EXPECT_EQ(test, roundup((1 << 30) - 1, 2), 1 << 30); + KUNIT_EXPECT_EQ(test, roundup((1 << 30) - 1, 1 << 29), 1 << 30); + + KUNIT_EXPECT_EQ(test, roundup(3, 2), 4); + KUNIT_EXPECT_EQ(test, roundup(4, 3), 6); +} + +static void rounddown_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, rounddown(0, 1), 0); + KUNIT_EXPECT_EQ(test, rounddown(1, 2), 0); + KUNIT_EXPECT_EQ(test, rounddown(3, 2), 2); + KUNIT_EXPECT_EQ(test, rounddown((1 << 30) - 1, 2), (1 << 30) - 2); + KUNIT_EXPECT_EQ(test, rounddown((1 << 30) - 1, 1 << 29), 1 << 29); + + KUNIT_EXPECT_EQ(test, rounddown(3, 2), 2); + KUNIT_EXPECT_EQ(test, rounddown(4, 3), 3); +} + +static void div_round_up_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(0, 1), 0); + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(20, 10), 2); + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 10), 3); + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 20), 2); + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 99), 1); +} + +static void div_round_closest_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(0, 1), 0); + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(20, 10), 2); + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(21, 10), 2); + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(25, 10), 3); +} + +/* Generic test case for unsigned long inputs. */ +struct test_case { + unsigned long a, b; + unsigned long result; +}; + +static struct test_case gcd_cases[] = { + { + .a = 0, .b = 0, + .result = 0, + }, + { + .a = 0, .b = 1, + .result = 1, + }, + { + .a = 2, .b = 2, + .result = 2, + }, + { + .a = 2, .b = 4, + .result = 2, + }, + { + .a = 3, .b = 5, + .result = 1, + }, + { + .a = 3 * 9, .b = 3 * 5, + .result = 3, + }, + { + .a = 3 * 5 * 7, .b = 3 * 5 * 11, + .result = 15, + }, + { + .a = 1 << 21, + .b = (1 << 21) - 1, + .result = 1, + }, +}; + +KUNIT_ARRAY_PARAM(gcd, gcd_cases, NULL); + +static void gcd_test(struct kunit *test) +{ + const char *message_fmt = "gcd(%lu, %lu)"; + const struct test_case *test_param = test->param_value; + + KUNIT_EXPECT_EQ_MSG(test, test_param->result, + gcd(test_param->a, test_param->b), + message_fmt, test_param->a, + test_param->b); + + if (test_param->a == test_param->b) + return; + + /* gcd(a,b) == gcd(b,a) */ + KUNIT_EXPECT_EQ_MSG(test, test_param->result, + gcd(test_param->b, test_param->a), + message_fmt, test_param->b, + test_param->a); +} + +static struct test_case lcm_cases[] = { + { + .a = 0, .b = 0, + .result = 0, + }, + { + .a = 0, .b = 1, + .result = 0, + }, + { + .a = 1, .b = 2, + .result = 2, + }, + { + .a = 2, .b = 2, + .result = 2, + }, + { + .a = 3 * 5, .b = 3 * 7, + .result = 3 * 5 * 7, + }, +}; + +KUNIT_ARRAY_PARAM(lcm, lcm_cases, NULL); + +static void lcm_test(struct kunit *test) +{ + const char *message_fmt = "lcm(%lu, %lu)"; + const struct test_case *test_param = test->param_value; + + KUNIT_EXPECT_EQ_MSG(test, test_param->result, + lcm(test_param->a, test_param->b), + message_fmt, test_param->a, + test_param->b); + + if (test_param->a == test_param->b) + return; + + /* lcm(a,b) == lcm(b,a) */ + KUNIT_EXPECT_EQ_MSG(test, test_param->result, + lcm(test_param->b, test_param->a), + message_fmt, test_param->b, + test_param->a); +} + +struct u32_test_case { + u32 a, b; + u32 result; +}; + +static struct u32_test_case reciprocal_div_cases[] = { + { + .a = 0, .b = 1, + .result = 0, + }, + { + .a = 42, .b = 20, + .result = 2, + }, + { + .a = 42, .b = 9999, + .result = 0, + }, + { + .a = (1 << 16), .b = (1 << 14), + .result = 1 << 2, + }, +}; + +KUNIT_ARRAY_PARAM(reciprocal_div, reciprocal_div_cases, NULL); + +static void reciprocal_div_test(struct kunit *test) +{ + const struct u32_test_case *test_param = test->param_value; + struct reciprocal_value rv = reciprocal_value(test_param->b); + + KUNIT_EXPECT_EQ_MSG(test, test_param->result, + reciprocal_divide(test_param->a, rv), + "reciprocal_divide(%u, %u)", + test_param->a, test_param->b); +} + +static void reciprocal_scale_test(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, reciprocal_scale(0u, 100), 0u); + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u, 100), 0u); + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u << 4, 1 << 28), 1u); + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u << 16, 1 << 28), 1u << 12); + KUNIT_EXPECT_EQ(test, reciprocal_scale(~0u, 1 << 28), (1u << 28) - 1); +} + +static struct kunit_case math_test_cases[] = { + KUNIT_CASE(abs_test), + KUNIT_CASE(int_sqrt_test), + KUNIT_CASE(round_up_test), + KUNIT_CASE(round_down_test), + KUNIT_CASE(roundup_test), + KUNIT_CASE(rounddown_test), + KUNIT_CASE(div_round_up_test), + KUNIT_CASE(div_round_closest_test), + KUNIT_CASE_PARAM(gcd_test, gcd_gen_params), + KUNIT_CASE_PARAM(lcm_test, lcm_gen_params), + KUNIT_CASE_PARAM(reciprocal_div_test, reciprocal_div_gen_params), + KUNIT_CASE(reciprocal_scale_test), + {} +}; + +static struct kunit_suite math_test_suite = { + .name = "lib-math", + .test_cases = math_test_cases, +}; + +kunit_test_suites(&math_test_suite); + +MODULE_LICENSE("GPL v2"); base-commit: 7e25f40eab52c57ff6772d27d2aef3640a3237d7 -- 2.31.1.368.gbe11c130af-goog

2 months, 1 week

5
5
0 0

[PATCH v2] selftests/kselftest/runner/run_one(): Allow running non-executable files

by SeongJae Park

From: SeongJae Park <sjpark(a)amazon.de> When running a test program, 'run_one()' checks if the program has the execution permission and fails if it doesn't. However, it's easy to mistakenly missing the permission, as some common tools like 'diff' don't support the permission change well[1]. Compared to that, making mistakes in the test program's path would only rare, as those are explicitly listed in 'TEST_PROGS'. Therefore, it might make more sense to resolve the situation on our own and run the program. For the reason, this commit makes the test program runner function to still print the warning message but try parsing the interpreter of the program and explicitly run it with the interpreter, in the case. [1] https://lore.kernel.org/mm-commits/YRJisBs9AunccCD4@kroah.com/ Suggested-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: SeongJae Park <sjpark(a)amazon.de> --- Changes from v1 (https://lore.kernel.org/linux-kselftest/20210810140459.23990-1-sj38.park@gm…) - Parse and use the interpreter instead of changing the file tools/testing/selftests/kselftest/runner.sh | 28 +++++++++++++-------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/kselftest/runner.sh b/tools/testing/selftests/kselftest/runner.sh index cc9c846585f0..a9ba782d8ca0 100644 --- a/tools/testing/selftests/kselftest/runner.sh +++ b/tools/testing/selftests/kselftest/runner.sh @@ -33,9 +33,9 @@ tap_timeout() { # Make sure tests will time out if utility is available. if [ -x /usr/bin/timeout ] ; then - /usr/bin/timeout --foreground "$kselftest_timeout" "$1" + /usr/bin/timeout --foreground "$kselftest_timeout" $1 else - "$1" + $1 fi } @@ -65,17 +65,25 @@ run_one() TEST_HDR_MSG="selftests: $DIR: $BASENAME_TEST" echo "# $TEST_HDR_MSG" - if [ ! -x "$TEST" ]; then - echo -n "# Warning: file $TEST is " - if [ ! -e "$TEST" ]; then - echo "missing!" - else - echo "not executable, correct this." - fi + if [ ! -e "$TEST" ]; then + echo "# Warning: file $TEST is missing!" echo "not ok $test_num $TEST_HDR_MSG" else + cmd="./$BASENAME_TEST" + if [ ! -x "$TEST" ]; then + echo "# Warning: file $TEST is not executable" + + if [ $(head -n 1 "$TEST" | cut -c -2) = "#!" ] + then + interpreter=$(head -n 1 "$TEST" | cut -c 3-) + cmd="$interpreter ./$BASENAME_TEST" + else + echo "not ok $test_num $TEST_HDR_MSG" + return + fi + fi cd `dirname $TEST` > /dev/null - ((((( tap_timeout ./$BASENAME_TEST 2>&1; echo $? >&3) | + ((((( tap_timeout "$cmd" 2>&1; echo $? >&3) | tap_prefix >&4) 3>&1) | (read xs; exit $xs)) 4>>"$logfile" && echo "ok $test_num $TEST_HDR_MSG") || -- 2.17.1

1 year, 3 months

3
6
0 0

[PATCH net-next v2 0/3] net: introduce rps_default_mask

by Paolo Abeni

Real-time setups try hard to ensure proper isolation between time critical applications and e.g. network processing performed by the network stack in softirq and RPS is used to move the softirq activity away from the isolated core. If the network configuration is dynamic, with netns and devices routinely created at run-time, enforcing the correct RPS setting on each newly created device allowing to transient bad configuration became complex. These series try to address the above, introducing a new sysctl knob: rps_default_mask. The new sysctl entry allows configuring a systemwide RPS mask, to be enforced since receive queue creation time without any fourther per device configuration required. Additionally, a simple self-test is introduced to check the rps_default_mask behavior. v1 -> v2: - fix sparse warning in patch 2/3 Paolo Abeni (3): net/sysctl: factor-out netdev_rx_queue_set_rps_mask() helper net/core: introduce default_rps_mask netns attribute self-tests: introduce self-tests for RPS default mask Documentation/admin-guide/sysctl/net.rst | 6 ++ include/linux/netdevice.h | 1 + net/core/net-sysfs.c | 73 +++++++++++-------- net/core/sysctl_net_core.c | 58 +++++++++++++++ tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/config | 3 + .../testing/selftests/net/rps_default_mask.sh | 57 +++++++++++++++ 7 files changed, 169 insertions(+), 30 deletions(-) create mode 100755 tools/testing/selftests/net/rps_default_mask.sh -- 2.26.2

1 year, 5 months

4
12
0 0

[PATCH v2 net-next 0/3] ptp: Add adjust phase to support phase offset.

by vincent.cheng.xh＠renesas.com

From: Vincent Cheng <vincent.cheng.xh(a)renesas.com> This series adds adjust phase to the PTP Hardware Clock device interface. Some PTP hardware clocks have a write phase mode that has a built-in hardware filtering capability. The write phase mode utilizes a phase offset control word instead of a frequency offset control word. Add adjust phase function to take advantage of this capability. Changes since v1: - As suggested by Richard Cochran: 1. ops->adjphase is new so need to check for non-null function pointer. 2. Kernel coding style uses lower_case_underscores. 3. Use existing PTP clock API for delayed worker. Vincent Cheng (3): ptp: Add adjphase function to support phase offset control. ptp: Add adjust_phase to ptp_clock_caps capability. ptp: ptp_clockmatrix: Add adjphase() to support PHC write phase mode. drivers/ptp/ptp_chardev.c | 1 + drivers/ptp/ptp_clock.c | 3 ++ drivers/ptp/ptp_clockmatrix.c | 92 +++++++++++++++++++++++++++++++++++ drivers/ptp/ptp_clockmatrix.h | 8 ++- include/linux/ptp_clock_kernel.h | 6 ++- include/uapi/linux/ptp_clock.h | 4 +- tools/testing/selftests/ptp/testptp.c | 6 ++- 7 files changed, 114 insertions(+), 6 deletions(-) -- 2.7.4

1 year, 11 months

5
8
0 0

Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to, KVM_MAX_VCPU_IDS

by Christian Zigotzky

Hello Juergen, Hello All, Since the RC1 of kernel 5.13, -smp 2 and -smp 4 don't work with a virtual e5500 QEMU KVM-HV machine anymore. [1] I see in the serial console, that the uImage doesn't load. I use the following QEMU command for booting: qemu-system-ppc64 -M ppce500 -cpu e5500 -enable-kvm -m 1024 -kernel uImage -drive format=raw,file=MintPPC32-X5000.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-vga -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -device usb-audio,bus=newusb.0 -smp 4 The kernels boot without KVM-HV. Summary for KVM-HV: -smp 1 -> works -smp 2 -> doesn't work -smp 3 -> works -smp 4 -> doesn't work I used -smp 4 before the RC1 of kernel 5.13 because my FSL P5040 BookE machine [2] has 4 cores. Does this patch solve this issue? [3] Thanks, Christian [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-May/229103.html [2] http://wiki.amiga.org/index.php?title=X5000 [3] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-September/234152.html

2 years

1
1
0 0

[PATCH v9 0/6] test_sysfs: add new selftest for sysfs

by Luis Chamberlain

On this v9 I've dropped the generic sysfs deadlock fix given Ming Lei has provided alternative fixes for the zram driver without incurring a generic lock *and* we don't yet have full assessment of how wide spread the deadlock case might be in the kernel. A full assessment effort is still underway using Coccinelle with iteration support, however that effort will take a bit more time to complete. We can re-evaluate the value of a generic fix later after the assessment is complete. This series now just adds the test_sysfs selftest and failure injection support for it on kernfs. The most valuable tests are those which confirm that once a kernfs active reference is obtained with kernfs_get_active() the pointers used there are still valid, and so using sysfs ops *are* safe if we race against module removal. Likewise it also confirms how module removal will *wait* for these ops to complete if a kernfs node is already active. This v9 series also addresses feedback mostly provided by Kees Cook and Greg. I also made a few changes to the test_sysfs driver to account for changes in the block layer. I also improved the kernfs failure injection tests with documentation of how they work and to account for the real expected return value of a write before the kernfs active reference is obtained. Upstream commit 8e141f9eb803e ("block: drain file system I/O on del_gendisk") has revealed that small minor induced delays on del_gendisk() can make a few writes succeed if the delays used are small. So we clarify the logic of why writes could either fail or succeed before the kernfs active reference is taken. These changes also availble on this tree: https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?… v9: * rebased onto linux-next tag next-20211029 * add Reviewed-by tags for the SPDX change, and the drivers which get the tag for it * drop the generic sysfs deadlock fix for now as the scope of how wide spread the issue is still needs to be assessed * drop the zram patches as they are replaced by Ming Lei's fixes * drop already merged patches * try_module_get() docs: enhanced using feedback from Kees Cook. I extended the documention to make it clear that if proper care is not taken the use of this routine could crash the kernel. * kernfs: move failure injection knobs under /sys/kernel/debug/fail_kernfs as suggested by Kees Cook * kernfs: rename failure injection file to fault_inject.c as suggested by Kees Cook * kernfs: split up documentation of failure injection knobs as suggested by Kees Cook * kernfs: move the wait into debug call, and use a simple one liner may_wait() calls to make the changes much less intrusive and more readable as suggested by Kees Cook * kernfs: drop __func__ uses as suggested by Kees Cook * test_sysfs: use sizeof() instead of open coded 16 as suggested by Kees Cook * test_sysfs: use sysfs_emit as suggested by Kees Cook * test_sysfs: drop boiler place license as suggested by Greg KH * test_sysfs: use depends instead of select as suggested by Kees Cook * test_sysfs: drop #ifdefery as suggested by Kees Cook * test_sysfs: clarified that the use of a lock on rmmod which causes a deadlock is something drivers should avoid, and its why we leave the test disabled. * test_sysfs: now that device_add_disk() returns an error, use the new error return code, otherwise this is going to prevent us from eventually embracing __must_check() on that call on the block layer. * test_syfs: testdev_submit_bio() needed to change data types as now it returns void. * test_sysfs: enhance kernfs failure injection tests with documenation and correct the expected return value for writes Luis Chamberlain (6): LICENSES: Add the copyleft-next-0.3.1 license testing: use the copyleft-next-0.3.1 SPDX tag selftests: add tests_sysfs module kernfs: add initial failure injection support test_sysfs: add support to use kernfs failure injection kernel/module: add documentation for try_module_get() .../fault-injection/fault-injection.rst | 50 + LICENSES/dual/copyleft-next-0.3.1 | 237 +++ MAINTAINERS | 9 +- fs/kernfs/Makefile | 1 + fs/kernfs/fault_inject.c | 93 ++ fs/kernfs/file.c | 9 + fs/kernfs/kernfs-internal.h | 70 + include/linux/kernfs.h | 5 + include/linux/module.h | 37 +- lib/Kconfig.debug | 23 + lib/Makefile | 1 + lib/test_kmod.c | 12 +- lib/test_sysctl.c | 12 +- lib/test_sysfs.c | 913 +++++++++++ tools/testing/selftests/kmod/kmod.sh | 13 +- tools/testing/selftests/sysctl/sysctl.sh | 12 +- tools/testing/selftests/sysfs/Makefile | 12 + tools/testing/selftests/sysfs/config | 5 + tools/testing/selftests/sysfs/settings | 1 + tools/testing/selftests/sysfs/sysfs.sh | 1411 +++++++++++++++++ 20 files changed, 2878 insertions(+), 48 deletions(-) create mode 100644 LICENSES/dual/copyleft-next-0.3.1 create mode 100644 fs/kernfs/fault_inject.c create mode 100644 lib/test_sysfs.c create mode 100644 tools/testing/selftests/sysfs/Makefile create mode 100644 tools/testing/selftests/sysfs/config create mode 100644 tools/testing/selftests/sysfs/settings create mode 100755 tools/testing/selftests/sysfs/sysfs.sh -- 2.30.2

2 years, 1 month

9
35
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[PATCH v3 0/6] KVM: my debug patch queue

by Maxim Levitsky

Hi! I would like to publish two debug features which were needed for other stuff I work on. One is the reworked lx-symbols script which now actually works on at least gdb 9.1 (gdb 9.2 was reported to fail to load the debug symbols from the kernel for some reason, not related to this patch) and upstream qemu. The other feature is the ability to trap all guest exceptions (on SVM for now) and see them in kvmtrace prior to potential merge to double/triple fault. This can be very useful and I already had to manually patch KVM a few times for this. I will, once time permits, implement this feature on Intel as well. V2: * Some more refactoring and workarounds for lx-symbols script * added KVM_GUESTDBG_BLOCKIRQ flag to enable 'block interrupts on single step' together with KVM_CAP_SET_GUEST_DEBUG2 capability to indicate which guest debug flags are supported. This is a replacement for unconditional block of interrupts on single step that was done in previous version of this patch set. Patches to qemu to use that feature will be sent soon. * Reworked the the 'intercept all exceptions for debug' feature according to the review feedback: - renamed the parameter that enables the feature and moved it to common kvm module. (only SVM part is currently implemented though) - disable the feature for SEV guests as was suggested during the review - made the vmexit table const again, as was suggested in the review as well. V3: * Modified a selftest to cover the KVM_GUESTDBG_BLOCKIRQ * Rebased on kvm/queue Best regards, Maxim Levitsky Maxim Levitsky (6): KVM: SVM: split svm_handle_invalid_exit KVM: x86: add force_intercept_exceptions_mask KVM: SVM: implement force_intercept_exceptions_mask scripts/gdb: rework lx-symbols gdb script KVM: x86: implement KVM_GUESTDBG_BLOCKIRQ KVM: selftests: test KVM_GUESTDBG_BLOCKIRQ Documentation/virt/kvm/api.rst | 1 + arch/x86/include/asm/kvm_host.h | 5 +- arch/x86/include/uapi/asm/kvm.h | 1 + arch/x86/kvm/svm/svm.c | 87 +++++++- arch/x86/kvm/svm/svm.h | 6 +- arch/x86/kvm/x86.c | 12 +- arch/x86/kvm/x86.h | 2 + kernel/module.c | 8 +- scripts/gdb/linux/symbols.py | 203 ++++++++++++------ .../testing/selftests/kvm/x86_64/debug_regs.c | 24 ++- 10 files changed, 266 insertions(+), 83 deletions(-) -- 2.26.3

2 years, 4 months

4
27
0 0

RFC - kernel test result specification (KTAP)

by Rae Moar

We are looking to further standardise the output format used by kernel test frameworks like kselftest and KUnit. Thus far we have used the TAP (Test Anything Protocol) specification, but it has been extended in many different ways, so we would like to agree on a common "Kernel TAP" (KTAP) format to resolve these differences. Thus, below is a draft of a specification of KTAP. Note that this specification is largely based on the current format of test results for KUnit tests. Additionally, this specification was heavily inspired by the KTAP specification draft by Tim Bird (https://lore.kernel.org/linux-kselftest/CY4PR13MB1175B804E31E502221BC8163FD…). However, there are some notable differences to his specification. One such difference is the format of nested tests is more fully specified in the following specification. However, they are specified in a way which may not be compatible with many kselftest nested tests. ===================== Specification of KTAP ===================== TAP, or the Test Anything Protocol is a format for specifying test results used by a number of projects. It's website and specification are found at: https://testanything.org/. The Linux Kernel uses TAP output for test results. However, KUnit (and other Kernel testing frameworks such as kselftest) have some special needs for test results which don't gel perfectly with the original TAP specification. Thus, a "Kernel TAP" (KTAP) format is specified to extend and alter TAP to support these use-cases. KTAP Output consists of 5 major elements (all line-based): - The version line - Plan lines - Test case result lines - Diagnostic lines - A bail out line An important component in this specification of KTAP is the specification of the format of nested tests. This can be found in the section on nested tests below. The version line ---------------- The first line of KTAP output must be the version line. As this specification documents the first version of KTAP, the recommended version line is "KTAP version 1". However, since all kernel testing frameworks use TAP version lines, "TAP version 14" and "TAP version 13" are all acceptable version lines. Version lines with other versions of TAP or KTAP will not cause the parsing of the test results to fail but it will produce an error. Plan lines ---------- Plan lines must follow the format of "1..N" where N is the number of subtests. The second line of KTAP output must be a plan line, which indicates the number of tests at the highest level, such that the tests do not have a parent. Also, in the instance of a test having subtests, the second line of the test after the subtest header must be a plan line which indicates the number of subtests within that test. Test case result lines ---------------------- Test case result lines must have the format: <result> <number> [-] [<description>] [<directive>] [<diagnostic data>] The result can be either "ok", which indicates the test case passed, or "not ok", which indicates that the test case failed. The number represents the number of the test case or suite being performed. The first test case or suite must have the number 1 and the number must increase by 1 for each additional test case or result at the same level and within the same testing suite. The "-" character is optional. The description is a description of the test, generally the name of the test, and can be any string of words (can't include #). The description is optional. The directive is used to indicate if a test was skipped. The format for the directive is: "# SKIP [<skip_description>]". The skip_description is optional and can be any string of words to describe why the test was skipped. The result of the test case result line can be either "ok" or "not ok" if the skip directive is used. Finally, note that TAP 14 specification includes TODO directives but these are not supported for KTAP. Examples of test case result lines: Test passed: ok 1 - test_case_name Test was skipped: not ok 1 - test_case_name # SKIP test_case_name should be skipped Test failed: not_ok 1 - test_case_name Diagnostic lines ---------------- Diagnostic lines are used for description of testing operations. Diagnostic lines are generally formatted as "# <diagnostic_description>", where the description can be any string. However, in practice, diagnostic lines are all lines that don't follow the format of any other KTAP line format. Diagnostic lines can be anywhere in the test output after the first two lines. There are a few special diagnostic lines. Diagnostic lines of the format "# Subtest: <test_name>" indicate the start of a test with subtests. Also, diagnostic lines of the format "# <test_name>: <description>" refer to a specific test and tend to occur before the test result line of that test but are optional. Bail out line ------------- A bail out line can occur anywhere in the KTAP output and will indicate that a test has crashed. The format of a bail out line is "Bail out! [<description>]", where the description can give information on why the bail out occurred and can be any string. Nested tests ------------ The new specification for KTAP will support an arbitrary number of nested subtests. Thus, tests can now have subtests and those subtests can have subtests. This can be useful to further categorize tests and organize test results. The new required format for a test with subtests consists of: a subtest header line, a plan line, all subtests, and a final test result line. The first line of the test must be the subtest header line with the format: "# Subtest: <test_name>". The second line of the test must be the plan line, which is formatted as "1..N", where N is the number of subtests. Following the plan line, all lines pertaining to the subtests will follow. Finally, the last line of the test is a final test result line with the format: "(ok|not ok) <number> [-] [<description>] [<directive>] [<diagnostic data>]", which follows the same format as the general test result lines described in this section. The result line should indicate the result of the subtests. Thus, if one of the subtests fail, the test should fail. The description in the final test result line should match the name of the test in the subtest header. An example format: KTAP version 1 1..1 # Subtest: test_suite 1..2 ok 1 - test_1 ok 2 - test_2 ok 1 - test_suite An example format with multiple levels of nested testing: KTAP version 1 1..1 # Subtest: test_suite 1..2 # Subtest: sub_test_suite 1..2 ok 1 - test_1 ok 2 test_2 ok 1 - sub_test_suite ok 2 - test ok 1 - test_suite In the instance that the plan line is missing, the end of the test will be denoted by the final result line containing a description that matches the name of the test given in the subtest header. Note that thus, if the plan line is missing and one of the subtests have a matching name to the test suite this will cause errors. Lastly, indentation is also recommended for improved readability. Major differences between TAP 14 and KTAP specification ------------------------------------------------------- Note that the major differences between TAP 14 and KTAP specification: - yaml and json are not allowed in diagnostic messages - TODO directive not allowed - KTAP allows for an arbitrary number of tests to be nested with specified nested test format Example of KTAP --------------- KTAP version 1 1..1 # Subtest: test_suite 1..1 # Subtest: sub_test_suite 1..2 ok 1 - test_1 ok 2 test_2 ok 1 - sub_test_suite ok 1 - test_suite ========================================= Note on incompatibilities with kselftests ========================================= To my knowledge, the above specification seems to generally accept the TAP format of many non-nested test results of kselftests. An example of a common kselftests TAP format for non-nested test results that are accepted by the above specification: TAP version 13 1..2 # selftests: vDSO: vdso_test_gettimeofday # The time is 1628024856.096879 ok 1 selftests: vDSO: vdso_test_gettimeofday # selftests: vDSO: vdso_test_getcpu # Could not find __vdso_getcpu ok 2 selftests: vDSO: vdso_test_getcpu # SKIP However, one major difference noted with kselftests is the use of more directives than the "# SKIP" directive. kselftest also supports XPASS and XFAIL directives. Some additional examples found in kselftests: not ok 5 selftests: netfilter: nft_concat_range.sh # TIMEOUT 45 seconds not ok 45 selftests: kvm: kvm_binary_stats_test # exit=127 Should the specification be expanded to include these directives? However, the general format for kselftests with nested test results seems to differ from the above specification. It seems that a general format for nested tests is as follows: TAP version 13 1..2 # selftests: membarrier: membarrier_test_single_thread # TAP version 13 # 1..2 # ok 1 sys_membarrier available # ok 2 sys membarrier invalid command test: command = -1, flags = 0, errno = 22. Failed as expected ok 1 selftests: membarrier: membarrier_test_single_thread # selftests: membarrier: membarrier_test_multi_thread # TAP version 13 # 1..2 # ok 1 sys_membarrier available # ok 2 sys membarrier invalid command test: command = -1, flags = 0, errno = 22. Failed as expected ok 2 selftests: membarrier: membarrier_test_multi_thread The major differences here, that do not match the above specification, are use of "# " as an indentation and using a TAP version line to denote a new test with subtests rather than the subtest header line described above. If these are widely utilized formats in kselftests, should we include both versions in the specification or should we attempt to agree on a single format for nested tests? I personally believe we should try to agree on a single format for nested tests. This would allow for a cleaner specification of KTAP and would reduce possible confusion. ==== So what do people think about the above specification? How should we handle the differences with kselftests? If this specification is accepted, where should the specification be documented?

2 years, 5 months

7
13
0 0

[PATCH] userfaultfd/selftests: use swap() to make code cleaner

by cgel.zte＠gmail.com

From: Changcheng Deng <deng.changcheng(a)zte.com.cn> Use swap() in order to make code cleaner. Issue found by coccinelle. Reported-by: Zeal Robot <zealci(a)zte.com.cn> Signed-off-by: Changcheng Deng <deng.changcheng(a)zte.com.cn> --- tools/testing/selftests/vm/userfaultfd.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 8a09057d2f22..41dfe6f4ebfb 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -1413,7 +1413,6 @@ static void userfaultfd_pagemap_test(unsigned int test_pgsize) static int userfaultfd_stress(void) { void *area; - char *tmp_area; unsigned long nr; struct uffdio_register uffdio_register; struct uffd_stats uffd_stats[nr_cpus]; @@ -1524,13 +1523,8 @@ static int userfaultfd_stress(void) count_verify[nr], nr); /* prepare next bounce */ - tmp_area = area_src; - area_src = area_dst; - area_dst = tmp_area; - - tmp_area = area_src_alias; - area_src_alias = area_dst_alias; - area_dst_alias = tmp_area; + swap(area_src, area_dst); + swap(area_src_alias, area_dst_alias); uffd_stats_report(uffd_stats, nr_cpus); } -- 2.25.1

2 years, 5 months

3
3
0 0

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Linux-kselftest-mirror October 2021