Files
linux/tools/testing/selftests/livepatch
Joe Lawrence 857300b7d5 selftests/livepatch: normalize sysctl error message
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] 6389deca5b
[2] b159c198c9

Reported-by: Dennis(Zhuoheng) Li <denli@redhat.com>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Reviewed-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220811212138.182575-1-joe.lawrence@redhat.com
2022-09-23 15:16:48 +02:00
..

====================
Livepatch Self Tests
====================

This is a small set of sanity tests for the kernel livepatching.

The test suite loads and unloads several test kernel modules to verify
livepatch behavior.  Debug information is logged to the kernel's message
buffer and parsed for expected messages.  (Note: the tests will compare
the message buffer for only the duration of each individual test.)


Config
------

Set these config options and their prerequisites:

CONFIG_LIVEPATCH=y
CONFIG_TEST_LIVEPATCH=m


Running the tests
-----------------

Test kernel modules are built as part of lib/ (make modules) and need to
be installed (make modules_install) as the test scripts will modprobe
them.

To run the livepatch selftests, from the top of the kernel source tree:

  % make -C tools/testing/selftests TARGETS=livepatch run_tests


Adding tests
------------

See the common functions.sh file for the existing collection of utility
functions, most importantly setup_config(), start_test() and
check_result().  The latter function greps the kernel's ring buffer for
"livepatch:" and "test_klp" strings, so tests be sure to include one of
those strings for result comparison.  Other utility functions include
general module loading and livepatch loading helpers (waiting for patch
transitions, sysfs entries, etc.)