[PATCH v2 5/6] selftests: livepatch: Check if replace 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 | 39 +++++++++++++++----------
 1 file changed, 23 insertions(+), 16 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index a2d649404a63..0cdaeef00983 100755
--- a/tools/testing/selftests/livepatch/test-sysfs.sh
+++ b/tools/testing/selftests/livepatch/test-sysfs.sh
@@ -9,6 +9,7 @@ MOD_LIVEPATCH2=test_klp_callbacks_demo
 MOD_LIVEPATCH3=test_klp_syscall
 
 HAS_PATCH_ATTR=0
+HAS_REPLACE_ATTR=0
 
 setup_config
 
@@ -22,7 +23,6 @@ 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 "$MOD_LIVEPATCH" "replace" "-r--r--r--"
 check_sysfs_rights "$MOD_LIVEPATCH" "stack_order" "-r--r--r--"
 check_sysfs_value  "$MOD_LIVEPATCH" "stack_order" "1"
 check_sysfs_rights "$MOD_LIVEPATCH" "transition" "-r--r--r--"
@@ -34,6 +34,11 @@ if does_sysfs_exists "$MOD_LIVEPATCH/vmlinux" "patched"; then
 	HAS_PATCH_ATTR=1
 fi
 
+if does_sysfs_exists "$MOD_LIVEPATCH" "replace"; then
+	check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
+	HAS_REPLACE_ATTR=1
+fi
+
 disable_lp $MOD_LIVEPATCH
 
 unload_lp $MOD_LIVEPATCH
@@ -96,18 +101,19 @@ livepatch: 'test_klp_callbacks_demo': unpatching complete
 % rmmod test_klp_callbacks_demo"
 fi
 
-start_test "sysfs test replace enabled"
+if [[ "$HAS_REPLACE_ATTR" == "1" ]]; then
+	start_test "sysfs test replace enabled"
 
-MOD_LIVEPATCH=test_klp_atomic_replace
-load_lp $MOD_LIVEPATCH replace=1
+	MOD_LIVEPATCH=test_klp_atomic_replace
+	load_lp $MOD_LIVEPATCH replace=1
 
-check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
-check_sysfs_value  "$MOD_LIVEPATCH" "replace" "1"
+	check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
+	check_sysfs_value  "$MOD_LIVEPATCH" "replace" "1"
 
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
+	disable_lp $MOD_LIVEPATCH
+	unload_lp $MOD_LIVEPATCH
 
-check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=1
+	check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=1
 livepatch: enabling patch '$MOD_LIVEPATCH'
 livepatch: '$MOD_LIVEPATCH': initializing patching transition
 livepatch: '$MOD_LIVEPATCH': starting patching transition
@@ -120,17 +126,17 @@ livepatch: '$MOD_LIVEPATCH': completing unpatching transition
 livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
 
-start_test "sysfs test replace disabled"
+	start_test "sysfs test replace disabled"
 
-load_lp $MOD_LIVEPATCH replace=0
+	load_lp $MOD_LIVEPATCH replace=0
 
-check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
-check_sysfs_value  "$MOD_LIVEPATCH" "replace" "0"
+	check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
+	check_sysfs_value  "$MOD_LIVEPATCH" "replace" "0"
 
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
+	disable_lp $MOD_LIVEPATCH
+	unload_lp $MOD_LIVEPATCH
 
-check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=0
+	check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=0
 livepatch: enabling patch '$MOD_LIVEPATCH'
 livepatch: '$MOD_LIVEPATCH': initializing patching transition
 livepatch: '$MOD_LIVEPATCH': starting patching transition
@@ -142,6 +148,7 @@ livepatch: '$MOD_LIVEPATCH': starting unpatching transition
 livepatch: '$MOD_LIVEPATCH': completing unpatching transition
 livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
+fi
 
 start_test "sysfs test stack_order value"
 

-- 
2.52.0