kernel.ftrace_enabled=0 is now refused on kernels that deprecate the
knob, so the old disable/reload flow no longer applies there. Probe
for this with ftrace_disable_supported() and keep the full original
scenario (disable, fail to load a livepatch, re-enable, load, confirm
disable is refused while loaded) on kernels where it still works;
otherwise just confirm the write is refused.
Link: https://patch.msgid.link/[email protected]
Suggested-by: Steven Rostedt <[email protected]>
Suggested-by: Joe Lawrence <[email protected]>
Assisted-by: Claude:claude-sonnet-5
Signed-off-by: Andrey Grodzovsky <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
When executing the command
"make -C tools/testing/selftests TARGETS=livepatch run_tests",
the following error message was reported.
TEST: livepatch interaction with ftrace_enabled sysctl ... not ok
...
livepatch: sysctlo
: setting key "kernel.ftrace_enabled": Device or resource busy
livepatch: sysctl: setting key "kernel.ftrace_enabled": 设备或资源忙
...
ERROR: livepatch kselftest(s) failed
not ok 5 selftests: livepatch: test-ftrace.sh # exit=1
To fix it, set LC_ALL=C.
Signed-off-by: Qiang Ma <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Acked-by: Petr Mladek <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
The commit 3dae09de40 ("livepatch: Add stack_order sysfs attribute"),
merged in v6.14, introduced a new sysfs attribute.
In order to run the selftests on older kernels, check if given kernel
has support for the attribute. If the attribute is not supported, skip
the checks.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
The commit adb68ed26a ("livepatch: Add "replace" sysfs attribute"),
merged in v6.11, introduced a new sysfs attribute.
In order to run the selftests on older kernels, check if given kernel
has support for the attribute. If the attribute is not supported, skip
the checks.
While at it, create a local variable to hold the module name to be
tested, instead of overwriting MOD_LIVEPATCH.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
The commit bb26cfd9e7
("livepatch: add sysfs entry "patched" for each klp_object") was merged
in v6.1, introducing a new sysfs attribute.
In order to run the selftests on older kernels, check if given kernel
has support for the attribute. If the attribute is not supported, skip
the checks.
Along with this change, use MOD_LIVEPATCH2 variable instead of
reassigning a new value to MOD_LIVEPATCH, and also use the variable
names in the check_result, to avoid using the module names.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
Older kernels don't support true/false for boolean module parameters
because they lack commit 0d6ea3ac94
("lib/kstrtox.c: add "false"/"true" support to kstrtobool()"). Replace
true/false by y/n so the test module can be loaded on older kernels.
No functional changes.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
Older kernels that lack CONFIG_ARCH_HAS_SYSCALL_WRAPPER config don't
have any prefixes for their syscalls. The same applies to current
powerpc and loongarch, covering all currently supported architectures
that support livepatch.
The other supported architectures have specific prefixes, so error out
when a new architecture adds livepatch support with wrappers but didn't
update the test to include it.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
Add a target module and livepatch pair that verify module function
patching via a proc entry. Two test cases cover both the
klp_enable_patch path (target loaded before livepatch) and the
klp_module_coming path (livepatch loaded before target).
Signed-off-by: Pablo Alessandro Santos Hugen <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Tested-by: Petr Mladek <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
Since v4.1 kernel, a new interface for ftrace called "tracefs" was
introduced, which is usually mounted in /sys/kernel/tracing. Therefore,
tracing files can now be accessed via either the legacy path
/sys/kernel/debug/tracing or the newer path /sys/kernel/tracing.
Signed-off-by: Fushuai Wang <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Tested-by: Petr Mladek <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Pull livepatching updates from Petr Mladek:
- Add a selftest for tracing of a livepatched function
- Skip a selftest when kprobes are not using ftrace
- Some documentation clean up
* tag 'livepatching-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
selftests: livepatch: test if ftrace can trace a livepatched function
selftests: livepatch: add new ftrace helpers functions
selftest/livepatch: Only run test-kprobe with CONFIG_KPROBES_ON_FTRACE
docs: livepatch: move text out of code block
livepatch: Add comment to clarify klp_add_nops()
The test proves that a function that is being kprobed and uses a
post_handler cannot be livepatched.
Only one ftrace_ops with FTRACE_OPS_FL_IPMODIFY set may be registered
to any given function at a time.
Note that the conflicting kprobe could not be created using the
tracefs interface, see Documentation/trace/kprobetrace.rst.
This interface uses only the pre_handler(), see alloc_trace_kprobe().
But FTRACE_OPS_FL_IPMODIFY is used only when the kprobe is using a
post_handler, see arm_kprobe_ftrace().
Signed-off-by: Michael Vetter <[email protected]>
Reviewed-by: Miroslav Benes <[email protected]>
Reviewed-by: Joe Lawrence <[email protected]>
Tested-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Tested-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Mladek <[email protected]>
Pull kselftest update from Shuah Khan:
- livepatch restructuring to move the module out of lib to be built as
a out-of-tree modules during kselftest build. This makes it easier
change, debug and rebuild the tests by running make on the
selftests/livepatch directory, which is not currently possible since
the modules on lib/livepatch are build and installed using the main
makefile modules target.
- livepatch restructuring fixes for problems found by kernel test
robot. The change skips the test if kernel-devel isn't installed
(default value of KDIR), or if KDIR variable passed doesn't exists.
- resctrl test restructuring and new non-contiguous CBMs CAT test
- new ktap_helpers to print diagnostic messages, pass/fail tests based
on exit code, abort test, and finish the test.
- a new test verify power supply properties.
- a new ftrace to exercise function tracer across cpu hotplug.
- timeout increase for mqueue test to allow the test to run on i3.metal
AWS instances.
- minor spelling corrections in several tests.
- missing gitignore files and changes to existing gitignore files.
* tag 'linux_kselftest-next-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (57 commits)
kselftest: Add basic test for probing the rust sample modules
selftests: lib.mk: Do not process TEST_GEN_MODS_DIR
selftests: livepatch: Avoid running the tests if kernel-devel is missing
selftests: livepatch: Add initial .gitignore
selftests/resctrl: Add non-contiguous CBMs CAT test
selftests/resctrl: Add resource_info_file_exists()
selftests/resctrl: Split validate_resctrl_feature_request()
selftests/resctrl: Add a helper for the non-contiguous test
selftests/resctrl: Add test groups and name L3 CAT test L3_CAT
selftests: sched: Fix spelling mistake "hiearchy" -> "hierarchy"
selftests/mqueue: Set timeout to 180 seconds
selftests/ftrace: Add test to exercize function tracer across cpu hotplug
selftest: ftrace: fix minor typo in log
selftests: thermal: intel: workload_hint: add missing gitignore
selftests: thermal: intel: power_floor: add missing gitignore
selftests: uevent: add missing gitignore
selftests: Add test to verify power supply properties
selftests: ktap_helpers: Add a helper to finish the test
selftests: ktap_helpers: Add a helper to abort the test
selftests: ktap_helpers: Add helper to pass/fail test based on exit code
...
Ignore the binary used to test livepatching a syscall.
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
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 <[email protected]>
Closes: https://lore.kernel.org/live-patching/[email protected]/
Signed-off-by: Joe Lawrence <[email protected]>
Acked-by: Alexander Gordeev <[email protected]>
Tested-by: Marcos Paulo de Souza <[email protected]>
Reviewed-by: Marcos Paulo de Souza <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
The test proves that a syscall can be livepatched. It is interesting
because syscalls are called a tricky way. Also the process gets
livepatched either when sleeping in the userspace or when entering
or leaving the kernel space.
The livepatch is a bit tricky:
1. The syscall function name is architecture specific. Also
ARCH_HAS_SYSCALL_WRAPPER must be taken in account.
2. The syscall must stay working the same way for other processes
on the system. It is solved by decrementing a counter only
for PIDs of the test processes. It means that the test processes
has to call the livepatched syscall at least once.
The test creates one userspace process per online cpu. The processes
are calling getpid in a busy loop. The intention is to create random
locations when the livepatch gets enabled. Nothing is guarantted.
The magic is in the randomness.
Reviewed-by: Joe Lawrence <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
The modules are being moved from lib/livepatch to
tools/testing/selftests/livepatch/test_modules.
This code moving will allow writing more complex tests, like for example an
userspace C code that will call a livepatched kernel function.
The modules are now built as out-of-tree
modules, but being part of the kernel source means they will be maintained.
Another advantage of the code moving is to be able to easily change,
debug and rebuild the tests by running make on the selftests/livepatch
directory, which is not currently possible since the modules on
lib/livepatch are build and installed using the "modules" target.
The current approach also keeps the ability to execute the tests manually
by executing the scripts inside selftests/livepatch directory, as it's
currently supported. If the modules are modified, they needed to be
rebuilt before running the scripts though.
The modules are built before running the selftests when using the
kselftest invocations:
make kselftest TARGETS=livepatch
or
make -C tools/testing/selftests/livepatch run_tests
Having the modules being built as out-of-modules requires changing the
currently used 'modprobe' by 'insmod' and adapt the test scripts that
check for the kernel message buffer.
Now it is possible to only compile the modules by running:
make -C tools/testing/selftests/livepatch/
This way the test modules and other test program can be built in order
to be packaged if so desired.
As there aren't any modules being built on lib/livepatch, remove the
TEST_LIVEPATCH Kconfig and it's references.
Note: "make gen_tar" packages the pre-built binaries into the tarball.
It means that it will store the test modules pre-built for
the kernel running on the build host.
Note that these modules need not binary compatible with
the kernel built from the same sources. But the same
is true for other packaged selftest binaries.
The entire kernel sources are needed for rebuilding
the selftests on another system.
Reviewed-by: Joe Lawrence <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Signed-off-by: Marcos Paulo de Souza <[email protected]>
Acked-by: Alexander Gordeev <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
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 <[email protected]>
Signed-off-by: David Vernet <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Tested-by: Petr Mladek <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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: 2f3f651f37 ("selftests/livepatch: Use "comm" instead of "diff" for dmesg")
Signed-off-by: Miroslav Benes <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>
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 <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Reviewed-by: Kamalesh Babulal <[email protected]>
Reviewed-by: Joe Lawrence <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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 <[email protected]>
Signed-off-by: Joe Lawrence <[email protected]>
Reviewed-by: Yannick Cote <[email protected]>
Reviewed-by: Kamalesh Babulal <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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 <[email protected]>
Reviewed-by: Kamalesh Babulal <[email protected]>
Reviewed-by: Yannick Cote <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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 <[email protected]>
Reviewed-by: Kamalesh Babulal <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Acked-by: Joe Lawrence <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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 <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Miroslav Benes <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Commit 852c8cbf34 ("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 b43e78f65b ("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: 852c8cbf34 ("selftests/kselftest/runner.sh: Add 45 second timeout per test")
Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
Andrey Grodzovsky