linux/tools/testing/selftests/livepatch, branch v6.8

selftests/livepatch: fix and refactor new dmesg message code

2024-01-30T15:55:42Z

The livepatching kselftests rely on comparing expected vs. observed dmesg output. After each test, new dmesg entries are determined by the 'comm' utility comparing a saved, pre-test copy of dmesg to post-test dmesg output. Alexander reports that the 'comm --nocheck-order -13' invocation used by the tests can be confused when dmesg entry timestamps vary in magnitude (ie, "[ 98.820331]" vs. "[ 100.031067]"), in which case, additional messages are reported as new. The unexpected entries then spoil the test results. Instead of relying on 'comm' or 'diff' to determine new testing dmesg entries, refactor the code: - pre-test : log a unique canary dmesg entry - test : run tests, log messages - post-test : filter dmesg starting from pre-test message Reported-by: Alexander Gordeev Closes: https://lore.kernel.org/live-patching/ZYAimyPYhxVA9wKg@li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com/ Signed-off-by: Joe Lawrence Acked-by: Alexander Gordeev Tested-by: Marcos Paulo de Souza Reviewed-by: Marcos Paulo de Souza Acked-by: Miroslav Benes Signed-off-by: Shuah Khan

Merge branch 'for-6.1/sysfs-patched-object' into for-linus

2022-10-05T11:00:03Z

selftests/livepatch: add sysfs test

2022-09-23T14:06:38Z

Add a test for livepatch sysfs entries. Signed-off-by: Song Liu Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220902205208.3117798-3-song@kernel.org

selftests/livepatch: normalize sysctl error message

2022-09-23T13:16:48Z

The livepatch kselftests rely on comparing expected and actual output from such commands as sysctl. A recent commit in procps-ng v4.0.0 [1] changed sysctl's output to emit key pathnames like: sysctl: setting key "/proc/sys/kernel/ftrace_enabled": Device or resource busy versus previous dotted output: sysctl: setting key "kernel.ftrace_enabled": Device or resource busy The modification in output was later reverted [2], but since the change has been tagged in procps-ng v4.0.0, update the livepatch kselftest to handle either case. [1] https://gitlab.com/procps-ng/procps/-/commit/6389deca5bf667f5fab5912acde78ba8e0febbc7 [2] https://gitlab.com/procps-ng/procps/-/commit/b159c198c9160a8eb13254e2b631d0035b9b542c Reported-by: Dennis(Zhuoheng) Li Signed-off-by: Joe Lawrence Reviewed-by: Kamalesh Babulal Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220811212138.182575-1-joe.lawrence@redhat.com

livepatch: Skip livepatch tests if ftrace cannot be configured

2022-02-23T15:42:00Z

livepatch has a set of selftests that are used to validate the behavior of the livepatching subsystem. One of the testcases in the livepatch testsuite is test-ftrace.sh, which among other things, validates that livepatching gracefully fails when ftrace is disabled. In the event that ftrace cannot be disabled using 'sysctl kernel.ftrace_enabled=0', the test will fail later due to it unexpectedly successfully loading the test_klp_livepatch module. While the livepatch selftests are careful to remove any of the livepatch test modules between testcases to avoid this situation, ftrace may still fail to be disabled if another trace is active on the system that was enabled with FTRACE_OPS_FL_PERMANENT. For example, any active BPF programs that use trampolines will cause this test to fail due to the trampoline being implemented with register_ftrace_direct(). The following is an example of such a trace: tcp_drop (1) R I D tramp: ftrace_regs_caller+0x0/0x58 (call_direct_funcs+0x0/0x30) direct-->bpf_trampoline_6442550536_0+0x0/0x1000 In order to make the test more resilient to system state that is out of its control, this patch updates set_ftrace_enabled() to detect sysctl failures, and skip the testrun when appropriate. Suggested-by: Petr Mladek Signed-off-by: David Vernet Acked-by: Miroslav Benes Reviewed-by: Petr Mladek Tested-by: Petr Mladek Acked-by: Joe Lawrence Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220216161100.3243100-1-void@manifault.com

selftests/livepatch: Do not check order when using "comm" for dmesg checking

2020-08-27T13:27:24Z

check_result() uses "comm" to check expected results of selftests output in dmesg. Everything works fine if timestamps in dmesg are unique. If not, like in this example [ 86.844422] test_klp_callbacks_demo: pre_unpatch_callback: test_klp_callbacks_mod -> [MODULE_STATE_LIVE] Normal state [ 86.844422] livepatch: 'test_klp_callbacks_demo': starting unpatching transition , "comm" fails with "comm: file 2 is not in sorted order". Suppress the order checking with --nocheck-order option. Fixes: 2f3f651f3756 ("selftests/livepatch: Use "comm" instead of "diff" for dmesg") Signed-off-by: Miroslav Benes Acked-by: Joe Lawrence Signed-off-by: Jiri Kosina

selftests/livepatch: adopt to newer sysctl error format

2020-07-15T06:54:35Z

With procfs v3.3.16, the sysctl command doesn't print the set key and value on error. This change breaks livepatch selftest test-ftrace.sh, that tests the interaction of sysctl ftrace_enabled: Make it work with all sysctl versions using '-q' option. Explicitly print the final status on success so that it can be verified in the log. The error message is enough on failure. Reported-by: Kamalesh Babulal Signed-off-by: Petr Mladek Reviewed-by: Kamalesh Babulal Reviewed-by: Joe Lawrence Acked-by: Miroslav Benes Link: https://lore.kernel.org/r/20200714091030.1611-1-pmladek@suse.com

selftests/livepatch: Use "comm" instead of "diff" for dmesg

2020-07-14T07:32:27Z

BusyBox diff doesn't support the GNU diff '--LTYPE-line-format' options that were used in the selftests to filter older kernel log messages from dmesg output. Use "comm" which is more available in smaller boot environments. Reported-by: Naresh Kamboju Signed-off-by: Joe Lawrence Reviewed-by: Yannick Cote Reviewed-by: Kamalesh Babulal Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20200710183745.19730-1-joe.lawrence@redhat.com

selftests/livepatch: add test delimiter to dmesg

2020-06-19T08:47:18Z

Make it bit easier to parse the kernel logs during the selftests by adding a "===== TEST: $test =====" delimiter when each individual test begins. Suggested-by: Petr Mladek Signed-off-by: Joe Lawrence Reviewed-by: Kamalesh Babulal Reviewed-by: Yannick Cote Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20200618181040.21132-4-joe.lawrence@redhat.com

selftests/livepatch: refine dmesg 'taints' in dmesg comparison

2020-06-19T08:47:04Z

The livepatch selftests currently grep on "taints" to filter out "tainting kernel with TAINT_LIVEPATCH" messages which may be logged when loading livepatch modules. Further filter the log to drop "loading out-of-tree module taints kernel" in the rare case the klp_test modules have been built out-of-tree. Look for the longer "taints kernel" or "tainting kernel" strings to avoid inadvertent partial matching. Signed-off-by: Joe Lawrence Reviewed-by: Kamalesh Babulal Reviewed-by: Yannick Cote Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20200618181040.21132-3-joe.lawrence@redhat.com