1 files changed, 56 insertions, 6 deletions

diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
index 30195449c63c..31eb09e38729 100644
--- a/tools/testing/selftests/livepatch/functions.sh
+++ b/tools/testing/selftests/livepatch/functions.sh
@@ -13,6 +13,14 @@ function log() {
 	echo "$1" > /dev/kmsg
 }
 
+# skip(msg) - testing can't proceed
+#	msg - explanation
+function skip() {
+	log "SKIP: $1"
+	echo "SKIP: $1" >&2
+	exit 4
+}
+
 # die(msg) - game over, man
 #	msg - dying words
 function die() {
@@ -21,13 +29,43 @@ function die() {
 	exit 1
 }
 
-# set_dynamic_debug() - setup kernel dynamic debug
-#	TODO - push and pop this config?
+function push_config() {
+	DYNAMIC_DEBUG=$(grep '^kernel/livepatch' /sys/kernel/debug/dynamic_debug/control | \
+			awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}')
+	FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled)
+}
+
+function pop_config() {
+	if [[ -n "$DYNAMIC_DEBUG" ]]; then
+		echo -n "$DYNAMIC_DEBUG" > /sys/kernel/debug/dynamic_debug/control
+	fi
+	if [[ -n "$FTRACE_ENABLED" ]]; then
+		sysctl kernel.ftrace_enabled="$FTRACE_ENABLED" &> /dev/null
+	fi
+}
+
 function set_dynamic_debug() {
-	cat << EOF > /sys/kernel/debug/dynamic_debug/control
-file kernel/livepatch/* +p
-func klp_try_switch_task -p
-EOF
+        cat <<-EOF > /sys/kernel/debug/dynamic_debug/control
+		file kernel/livepatch/* +p
+		func klp_try_switch_task -p
+		EOF
+}
+
+function set_ftrace_enabled() {
+	local sysctl="$1"
+	result=$(sysctl kernel.ftrace_enabled="$1" 2>&1 | paste --serial --delimiters=' ')
+	echo "livepatch: $result" > /dev/kmsg
+}
+
+# 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
+#		 the ftrace_enabled sysctl.
+function setup_config() {
+	push_config
+	set_dynamic_debug
+	set_ftrace_enabled 1
+	trap pop_config EXIT INT TERM HUP
 }
 
 # loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES,
@@ -43,6 +81,12 @@ function loop_until() {
 	done
 }
 
+function assert_mod() {
+	local mod="$1"
+
+	modprobe --dry-run "$mod" &>/dev/null
+}
+
 function is_livepatch_mod() {
 	local mod="$1"
 
@@ -75,6 +119,9 @@ function __load_mod() {
 function load_mod() {
 	local mod="$1"; shift
 
+	assert_mod "$mod" ||
+		skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
+
 	is_livepatch_mod "$mod" &&
 		die "use load_lp() to load the livepatch module $mod"
 
@@ -88,6 +135,9 @@ function load_mod() {
 function load_lp_nowait() {
 	local mod="$1"; shift
 
+	assert_mod "$mod" ||
+		skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
+
 	is_livepatch_mod "$mod" ||
 		die "module $mod is not a livepatch"