linux-toradex.git/tools/testing/selftests/livepatch, branch v5.19-rc4

livepatch: Skip livepatch tests if ftrace cannot be configured

2022-02-23T15:42:00+00:00

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

2020-08-27T13:27:24+00:00

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

2020-07-15T06:54:35+00:00

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

2020-07-14T07:32:27+00:00

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

2020-06-19T08:47:18+00:00

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

2020-06-19T08:47:04+00:00

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

selftests/livepatch: Don't clear dmesg when running tests

2020-06-19T08:46:42+00:00

Inspired by commit f131d9edc29d ("selftests/lkdtm: Don't clear dmesg
when running tests"), keep a reference dmesg copy when beginning each
test.  This way check_result() can compare against the initial copy
rather than relying upon an empty log.

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/20200618181040.21132-2-joe.lawrence@redhat.com

selftests/livepatch: more verification in test-klp-shadow-vars

2020-06-08T08:54:29+00:00

This change makes the test feel more familiar with narrowing to a
typical usage by operating on a number of identical structure instances
and populating the same two new shadow variables symmetrically while
keeping the same testing and verification criteria for the extra
variables.

Signed-off-by: Yannick Cote 
Reviewed-by: Kamalesh Babulal 
Reviewed-by: Petr Mladek 
Acked-by: Miroslav Benes 
Acked-by: Joe Lawrence 
Signed-off-by: Petr Mladek 
Link: https://lore.kernel.org/r/20200603182058.109470-4-ycote@redhat.com

selftests/livepatch: simplify test-klp-callbacks busy target tests

2020-06-08T08:36:10+00:00

The test-klp-callbacks script includes a few tests which rely on kernel
task timings that may not always execute as expected under system load.
These may generate out of sequence kernel log messages that result in
test failure.

Instead of using sleep timing windows to orchestrate these tests, add a
block_transition module parameter to communicate the test purpose and
utilize flush_queue() to serialize the test module's task output.

Signed-off-by: Joe Lawrence 
Reviewed-by: Petr Mladek 
Acked-by: Miroslav Benes 
Signed-off-by: Petr Mladek 
Link: https://lore.kernel.org/r/20200603182058.109470-2-ycote@redhat.com

selftests: Install settings files to fix TIMEOUT failures

2020-02-20T15:56:42+00:00

Commit 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second
timeout per test") added a 45 second timeout for tests, and also added
a way for tests to customise the timeout via a settings file.

For example the ftrace tests take multiple minutes to run, so they
were given longer in commit b43e78f65b1d ("tracing/selftests: Turn off
timeout setting").

This works when the tests are run from the source tree. However if the
tests are installed with "make -C tools/testing/selftests install",
the settings files are not copied into the install directory. When the
tests are then run from the install directory the longer timeouts are
not applied and the tests timeout incorrectly.

So add the settings files to TEST_FILES of the appropriate Makefiles
to cause the settings files to be installed using the existing install
logic.

Fixes: 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second timeout per test")
Signed-off-by: Michael Ellerman 
Signed-off-by: Shuah Khan