selftests/livepatch: Do not check order when using "comm" for dmesg checking

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: 2f3f651 ("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]>

Author: mirab

tools/testing/selftests/livepatch/functions.sh

@@ -278,7 +278,7 @@ function check_result {
 	# help differentiate repeated testing runs.  Remove them with a
 	# post-comparison sed filter.
 
-	result=$(dmesg | comm -13 "$SAVED_DMESG" - | \
+	result=$(dmesg | comm --nocheck-order -13 "$SAVED_DMESG" - | \
 		 grep -e 'livepatch:' -e 'test_klp' | \
 		 grep -v '\(tainting\|taints\) kernel' | \
 		 sed 's/^\[[ 0-9.]*\] //')