[PATCH v5 6/6] selftests: livepatch: Check if stack_order sysfs attribute exists

[Marcos Paulo de Souza]

The commit 3dae09de4061 ("livepatch: Add stack_order sysfs attribute"),
merged in v6.14, introduced a new sysfs attribute.

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 fed656021271..3b16285c6e67 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_exist "$MOD_LIVEPATCH" "replace"; then
 	HAS_REPLACE_ATTR=1
 fi
 
+if does_sysfs_exist "$MOD_LIVEPATCH" "stack_order"; then
+	check_sysfs_rights "$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 $MOD_LIVEPATCH
@@ -149,33 +154,34 @@ livepatch: '$MOD_ATOMIC_REPLACE': unpatching complete
 % rmmod $MOD_ATOMIC_REPLACE"
 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: '$MOD_LIVEPATCH': starting patching transition
@@ -215,5 +221,6 @@ livepatch: '$MOD_LIVEPATCH': starting unpatching transition
 livepatch: '$MOD_LIVEPATCH': completing unpatching transition
 livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
+fi
 
 exit 0

-- 
2.54.0