[PATCH v2 6/6] selftests: livepatch: Check if stack_order sysfs attribute exists

[Marcos Paulo de Souza]

In order to run the selftests on older kernels, check if given kernel
has support for the attribute. If the attribute is not supported, skip
the checks.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@xxxxxxxx>
---
 tools/testing/selftests/livepatch/test-sysfs.sh | 43 ++++++++++++++-----------
 1 file changed, 25 insertions(+), 18 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index 0cdaeef00983..77f515529646 100755
--- a/tools/testing/selftests/livepatch/test-sysfs.sh
+++ b/tools/testing/selftests/livepatch/test-sysfs.sh
@@ -10,6 +10,7 @@ MOD_LIVEPATCH3=test_klp_syscall
 
 HAS_PATCH_ATTR=0
 HAS_REPLACE_ATTR=0
+HAS_STACK_ORDER_ATTR=0
 
 setup_config
 
@@ -23,8 +24,6 @@ check_sysfs_rights "$MOD_LIVEPATCH" "" "drwxr-xr-x"
 check_sysfs_rights "$MOD_LIVEPATCH" "enabled" "-rw-r--r--"
 check_sysfs_value  "$MOD_LIVEPATCH" "enabled" "1"
 check_sysfs_rights "$MOD_LIVEPATCH" "force" "--w-------"
-check_sysfs_rights "$MOD_LIVEPATCH" "stack_order" "-r--r--r--"
-check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
 check_sysfs_rights "$MOD_LIVEPATCH" "transition" "-r--r--r--"
 check_sysfs_value  "$MOD_LIVEPATCH" "transition" "0"
 
@@ -39,6 +38,12 @@ if does_sysfs_exists "$MOD_LIVEPATCH" "replace"; then
 	HAS_REPLACE_ATTR=1
 fi
 
+if does_sysfs_exists "$MOD_LIVEPATCH" "stack_order"; then
+	check_sysfs_rights "$MOD_LIVEPATCH" "stack_order" "-r--r--r--"
+	check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
+	HAS_STACK_ORDER_ATTR=1
+fi
+
 disable_lp $MOD_LIVEPATCH
 
 unload_lp $MOD_LIVEPATCH
@@ -150,33 +155,34 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
 fi
 
-start_test "sysfs test stack_order value"
+if [[ "$HAS_STACK_ORDER_ATTR" == "1" ]]; then
+	start_test "sysfs test stack_order value"
 
-load_lp $MOD_LIVEPATCH
+	load_lp $MOD_LIVEPATCH
 
-check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
+	check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
 
-load_lp $MOD_LIVEPATCH2
+	load_lp $MOD_LIVEPATCH2
 
-check_sysfs_value  "$MOD_LIVEPATCH2" "stack_order" "2"
+	check_sysfs_value  "$MOD_LIVEPATCH2" "stack_order" "2"
 
-load_lp $MOD_LIVEPATCH3
+	load_lp $MOD_LIVEPATCH3
 
-check_sysfs_value  "$MOD_LIVEPATCH3" "stack_order" "3"
+	check_sysfs_value  "$MOD_LIVEPATCH3" "stack_order" "3"
 
-disable_lp $MOD_LIVEPATCH2
-unload_lp $MOD_LIVEPATCH2
+	disable_lp $MOD_LIVEPATCH2
+	unload_lp $MOD_LIVEPATCH2
 
-check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
-check_sysfs_value  "$MOD_LIVEPATCH3" "stack_order" "2"
+	check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
+	check_sysfs_value  "$MOD_LIVEPATCH3" "stack_order" "2"
 
-disable_lp $MOD_LIVEPATCH3
-unload_lp $MOD_LIVEPATCH3
+	disable_lp $MOD_LIVEPATCH3
+	unload_lp $MOD_LIVEPATCH3
 
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
+	disable_lp $MOD_LIVEPATCH
+	unload_lp $MOD_LIVEPATCH
 
-check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
+	check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
 livepatch: enabling patch '$MOD_LIVEPATCH'
 livepatch: '$MOD_LIVEPATCH': initializing patching transition
 livepatch: '$MOD_LIVEPATCH': starting patching transition
@@ -216,5 +222,6 @@ livepatch: '$MOD_LIVEPATCH': starting unpatching transition
 livepatch: '$MOD_LIVEPATCH': completing unpatching transition
 livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
+fi
 
 exit 0

-- 
2.52.0