[PATCH] selftests/livepatch: add test skip handling

[Joe Lawrence <joe.lawrence@xxxxxxxxxx>]

Before running a livpeatch self-test, first verify that we've built and
installed the livepatch self-test kernel modules by running a 'modprobe
--dry-run'.  This should catch a few environment issues, including
!CONFIG_LIVEPATCH and !CONFIG_TEST_LIVEPATCH.  In these cases, exit
gracefully with test-skip status rather than test-fail status.

Reported-by: Jiri Benc <jbenc@xxxxxxxxxx>
Suggested-by: Shuah Khan <shuah@xxxxxxxxxx>
Signed-off-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx>
---
 tools/testing/selftests/livepatch/functions.sh | 18 ++++++++++++++++++
 .../selftests/livepatch/test-callbacks.sh      |  5 +++++
 .../selftests/livepatch/test-livepatch.sh      |  3 +++
 .../selftests/livepatch/test-shadow-vars.sh    |  2 ++
 4 files changed, 28 insertions(+)

diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
index 30195449c63c..92d6cfb49365 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() {
@@ -43,6 +51,16 @@ function loop_until() {
 	done
 }
 
+function assert_mod() {
+	local mod="$1"
+
+	if ! modprobe --dry-run "$mod" &>/dev/null ; then
+		skip "Failed modprobe --dry-run of module: $mod"
+	fi
+
+	return 1
+}
+
 function is_livepatch_mod() {
 	local mod="$1"
 
diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh
index e97a9dcb73c7..87a407cee7fd 100755
--- a/tools/testing/selftests/livepatch/test-callbacks.sh
+++ b/tools/testing/selftests/livepatch/test-callbacks.sh
@@ -9,6 +9,11 @@ MOD_LIVEPATCH2=test_klp_callbacks_demo2
 MOD_TARGET=test_klp_callbacks_mod
 MOD_TARGET_BUSY=test_klp_callbacks_busy
 
+assert_mod $MOD_LIVEPATCH
+assert_mod $MOD_LIVEPATCH2
+assert_mod $MOD_TARGET
+assert_mod $MOD_TARGET_BUSY
+
 set_dynamic_debug
 
 
diff --git a/tools/testing/selftests/livepatch/test-livepatch.sh b/tools/testing/selftests/livepatch/test-livepatch.sh
index f05268aea859..8d3b75ceeeff 100755
--- a/tools/testing/selftests/livepatch/test-livepatch.sh
+++ b/tools/testing/selftests/livepatch/test-livepatch.sh
@@ -7,6 +7,9 @@
 MOD_LIVEPATCH=test_klp_livepatch
 MOD_REPLACE=test_klp_atomic_replace
 
+assert_mod $MOD_LIVEPATCH
+assert_mod $MOD_REPLACE
+
 set_dynamic_debug
 
 
diff --git a/tools/testing/selftests/livepatch/test-shadow-vars.sh b/tools/testing/selftests/livepatch/test-shadow-vars.sh
index 04a37831e204..1ab09bc50363 100755
--- a/tools/testing/selftests/livepatch/test-shadow-vars.sh
+++ b/tools/testing/selftests/livepatch/test-shadow-vars.sh
@@ -6,6 +6,8 @@
 
 MOD_TEST=test_klp_shadow_vars
 
+assert_mod $MOD_TEST
+
 set_dynamic_debug
 
 
-- 
2.21.0