Merge tag 'livepatching-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching

Pull livepatching updates from Petr Mladek:
 "Improvements and cleanups of livepatching selftests"

* tag 'livepatching-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  selftests/livepatch: adopt to newer sysctl error format
  selftests/livepatch: Use "comm" instead of "diff" for dmesg
  selftests/livepatch: add test delimiter to dmesg
  selftests/livepatch: refine dmesg 'taints' in dmesg comparison
  selftests/livepatch: Don't clear dmesg when running tests
  selftests/livepatch: fix mem leaks in test-klp-shadow-vars
  selftests/livepatch: more verification in test-klp-shadow-vars
  selftests/livepatch: rework test-klp-shadow-vars
  selftests/livepatch: simplify test-klp-callbacks busy target tests

1 files changed, 37 insertions, 3 deletions

diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
index 2aab9791791d..1aba83c87ad3 100644
--- a/tools/testing/selftests/livepatch/functions.sh
+++ b/tools/testing/selftests/livepatch/functions.sh
@@ -41,6 +41,17 @@ function die() {
 	exit 1
 }
 
+# save existing dmesg so we can detect new content
+function save_dmesg() {
+	SAVED_DMESG=$(mktemp --tmpdir -t klp-dmesg-XXXXXX)
+	dmesg > "$SAVED_DMESG"
+}
+
+# cleanup temporary dmesg file from save_dmesg()
+function cleanup_dmesg_file() {
+	rm -f "$SAVED_DMESG"
+}
+
 function push_config() {
 	DYNAMIC_DEBUG=$(grep '^kernel/livepatch' /sys/kernel/debug/dynamic_debug/control | \
 			awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}')
@@ -64,10 +75,16 @@ function set_dynamic_debug() {
 }
 
 function set_ftrace_enabled() {
-	result=$(sysctl kernel.ftrace_enabled="$1" 2>&1 | paste --serial --delimiters=' ')
+	result=$(sysctl -q kernel.ftrace_enabled="$1" 2>&1 && \
+		 sysctl kernel.ftrace_enabled 2>&1)
 	echo "livepatch: $result" > /dev/kmsg
 }
 
+function cleanup() {
+	pop_config
+	cleanup_dmesg_file
+}
+
 # setup_config - save the current config and set a script exit trap that
 #		 restores the original config.  Setup the dynamic debug
 #		 for verbose livepatching output and turn on
@@ -77,7 +94,7 @@ function setup_config() {
 	push_config
 	set_dynamic_debug
 	set_ftrace_enabled 1
-	trap pop_config EXIT INT TERM HUP
+	trap cleanup EXIT INT TERM HUP
 }
 
 # loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES,
@@ -243,13 +260,28 @@ function set_pre_patch_ret {
 		die "failed to set pre_patch_ret parameter for $mod module"
 }
 
+function start_test {
+	local test="$1"
+
+	save_dmesg
+	echo -n "TEST: $test ... "
+	log "===== TEST: $test ====="
+}
+
 # check_result() - verify dmesg output
 #	TODO - better filter, out of order msgs, etc?
 function check_result {
 	local expect="$*"
 	local result
 
-	result=$(dmesg | grep -v 'tainting' | grep -e 'livepatch:' -e 'test_klp' | sed 's/^\[[ 0-9.]*\] //')
+	# Note: when comparing dmesg output, the kernel log timestamps
+	# help differentiate repeated testing runs.  Remove them with a
+	# post-comparison sed filter.
+
+	result=$(dmesg | comm -13 "$SAVED_DMESG" - | \
+		 grep -e 'livepatch:' -e 'test_klp' | \
+		 grep -v '\(tainting\|taints\) kernel' | \
+		 sed 's/^\[[ 0-9.]*\] //')
 
 	if [[ "$expect" == "$result" ]] ; then
 		echo "ok"
@@ -257,4 +289,6 @@ function check_result {
 		echo -e "not ok\n\n$(diff -upr --label expected --label result <(echo "$expect") <(echo "$result"))\n"
 		die "livepatch kselftest(s) failed"
 	fi
+
+	cleanup_dmesg_file
 }