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Elixir Cross Referencer

====================
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 clear
the message buffer between individual tests.)


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 set_dynamic_debug() 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.)