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				The test_klp_callbacks_busy module conditionally blocks a future
livepatch transition by busy waiting inside its workqueue function,
busymod_work_func().  After scheduling this work, a test livepatch is
loaded, introducing the transition under test.
Both events are marked in the kernel log for later verification, but
there is no synchronization to ensure that busymod_work_func() logs its
function entry message before subsequent selftest commands log their own
messages.  This can lead to a rare test failure due to unexpected
ordering like:
  --- expected
  +++ result
  @@ -1,7 +1,7 @@
   % modprobe test_klp_callbacks_busy block_transition=Y
   test_klp_callbacks_busy: test_klp_callbacks_busy_init
  -test_klp_callbacks_busy: busymod_work_func enter
   % modprobe test_klp_callbacks_demo
  +test_klp_callbacks_busy: busymod_work_func enter
   livepatch: enabling patch 'test_klp_callbacks_demo'
   livepatch: 'test_klp_callbacks_demo': initializing patching transition
   test_klp_callbacks_demo: pre_patch_callback: vmlinux
Force the module init function to wait until busymod_work_func() has
started (and logged its message), before exiting to the next selftest
steps.
Fixes: 
		
	
					 | 
			||
|---|---|---|
| .. | ||
| Makefile | ||
| test_klp_atomic_replace.c | ||
| test_klp_callbacks_busy.c | ||
| test_klp_callbacks_demo.c | ||
| test_klp_callbacks_demo2.c | ||
| test_klp_callbacks_mod.c | ||
| test_klp_livepatch.c | ||
| test_klp_shadow_vars.c | ||
| test_klp_state.c | ||
| test_klp_state2.c | ||
| test_klp_state3.c | ||