[PATCH v5 4/6] selftests: livepatch: Check if patched sysfs attribute exists

[Marcos Paulo de Souza <mpdesouza@suse.com>]

The commit bb26cfd9e77e
("livepatch: add sysfs entry "patched" for each klp_object") was merged
in v6.1, introducing 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.

Along with this change, use MOD_LIVEPATCH2 variable instead of
reassigning a new value to MOD_LIVEPATCH, and also use the variable
names in the check_result, to avoid using the module names.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 tools/testing/selftests/livepatch/test-sysfs.sh | 87 +++++++++++++------------
 1 file changed, 47 insertions(+), 40 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index 58fe1d96997c..7fa2223f9533 100755
--- a/tools/testing/selftests/livepatch/test-sysfs.sh
+++ b/tools/testing/selftests/livepatch/test-sysfs.sh
@@ -8,6 +8,8 @@ MOD_LIVEPATCH=test_klp_livepatch
 MOD_LIVEPATCH2=test_klp_callbacks_demo
 MOD_LIVEPATCH3=test_klp_syscall
 
+HAS_PATCH_ATTR=0
+
 setup_config
 
 # - load a livepatch and verifies the sysfs entries work as expected
@@ -25,8 +27,12 @@ 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"
-check_sysfs_rights "$MOD_LIVEPATCH" "vmlinux/patched" "-r--r--r--"
-check_sysfs_value  "$MOD_LIVEPATCH" "vmlinux/patched" "1"
+
+if does_sysfs_exist "$MOD_LIVEPATCH/vmlinux" "patched"; then
+	check_sysfs_rights "$MOD_LIVEPATCH" "vmlinux/patched" "-r--r--r--"
+	check_sysfs_value  "$MOD_LIVEPATCH" "vmlinux/patched" "1"
+	HAS_PATCH_ATTR=1
+fi
 
 disable_lp $MOD_LIVEPATCH
 
@@ -45,48 +51,49 @@ livepatch: '$MOD_LIVEPATCH': completing unpatching transition
 livepatch: '$MOD_LIVEPATCH': unpatching complete
 % rmmod $MOD_LIVEPATCH"
 
-start_test "sysfs test object/patched"
+if [[ "$HAS_PATCH_ATTR" == "1" ]]; then
+	start_test "sysfs test object/patched"
 
-MOD_LIVEPATCH=test_klp_callbacks_demo
-MOD_TARGET=test_klp_callbacks_mod
-load_lp $MOD_LIVEPATCH
+	MOD_TARGET=test_klp_callbacks_mod
+	load_lp $MOD_LIVEPATCH2
 
-# check the "patch" file changes as target module loads/unloads
-check_sysfs_value  "$MOD_LIVEPATCH" "$MOD_TARGET/patched" "0"
-load_mod $MOD_TARGET
-check_sysfs_value  "$MOD_LIVEPATCH" "$MOD_TARGET/patched" "1"
-unload_mod $MOD_TARGET
-check_sysfs_value  "$MOD_LIVEPATCH" "$MOD_TARGET/patched" "0"
+	# check the "patch" file changes as target module loads/unloads
+	check_sysfs_value  "$MOD_LIVEPATCH2" "$MOD_TARGET/patched" "0"
+	load_mod $MOD_TARGET
+	check_sysfs_value  "$MOD_LIVEPATCH2" "$MOD_TARGET/patched" "1"
+	unload_mod $MOD_TARGET
+	check_sysfs_value  "$MOD_LIVEPATCH2" "$MOD_TARGET/patched" "0"
 
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
+	disable_lp $MOD_LIVEPATCH2
+	unload_lp $MOD_LIVEPATCH2
 
-check_result "% insmod test_modules/test_klp_callbacks_demo.ko
-livepatch: enabling patch 'test_klp_callbacks_demo'
-livepatch: 'test_klp_callbacks_demo': initializing patching transition
-test_klp_callbacks_demo: pre_patch_callback: vmlinux
-livepatch: 'test_klp_callbacks_demo': starting patching transition
-livepatch: 'test_klp_callbacks_demo': completing patching transition
-test_klp_callbacks_demo: post_patch_callback: vmlinux
-livepatch: 'test_klp_callbacks_demo': patching complete
-% insmod test_modules/test_klp_callbacks_mod.ko
-livepatch: applying patch 'test_klp_callbacks_demo' to loading module 'test_klp_callbacks_mod'
-test_klp_callbacks_demo: pre_patch_callback: test_klp_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init
-test_klp_callbacks_demo: post_patch_callback: test_klp_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init
-test_klp_callbacks_mod: test_klp_callbacks_mod_init
-% rmmod test_klp_callbacks_mod
-test_klp_callbacks_mod: test_klp_callbacks_mod_exit
-test_klp_callbacks_demo: pre_unpatch_callback: test_klp_callbacks_mod -> [MODULE_STATE_GOING] Going away
-livepatch: reverting patch 'test_klp_callbacks_demo' on unloading module 'test_klp_callbacks_mod'
-test_klp_callbacks_demo: post_unpatch_callback: test_klp_callbacks_mod -> [MODULE_STATE_GOING] Going away
-% echo 0 > $SYSFS_KLP_DIR/test_klp_callbacks_demo/enabled
-livepatch: 'test_klp_callbacks_demo': initializing unpatching transition
-test_klp_callbacks_demo: pre_unpatch_callback: vmlinux
-livepatch: 'test_klp_callbacks_demo': starting unpatching transition
-livepatch: 'test_klp_callbacks_demo': completing unpatching transition
-test_klp_callbacks_demo: post_unpatch_callback: vmlinux
-livepatch: 'test_klp_callbacks_demo': unpatching complete
-% rmmod test_klp_callbacks_demo"
+	check_result "% insmod test_modules/$MOD_LIVEPATCH2.ko
+livepatch: enabling patch '$MOD_LIVEPATCH2'
+livepatch: '$MOD_LIVEPATCH2': initializing patching transition
+$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
+livepatch: '$MOD_LIVEPATCH2': starting patching transition
+livepatch: '$MOD_LIVEPATCH2': completing patching transition
+$MOD_LIVEPATCH2: post_patch_callback: vmlinux
+livepatch: '$MOD_LIVEPATCH2': patching complete
+% insmod test_modules/$MOD_TARGET.ko
+livepatch: applying patch '$MOD_LIVEPATCH2' to loading module '$MOD_TARGET'
+$MOD_LIVEPATCH2: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
+$MOD_LIVEPATCH2: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
+$MOD_TARGET: test_klp_callbacks_mod_init
+% rmmod $MOD_TARGET
+$MOD_TARGET: test_klp_callbacks_mod_exit
+$MOD_LIVEPATCH2: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away
+livepatch: reverting patch '$MOD_LIVEPATCH2' on unloading module '$MOD_TARGET'
+$MOD_LIVEPATCH2: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away
+% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH2/enabled
+livepatch: '$MOD_LIVEPATCH2': initializing unpatching transition
+$MOD_LIVEPATCH2: pre_unpatch_callback: vmlinux
+livepatch: '$MOD_LIVEPATCH2': starting unpatching transition
+livepatch: '$MOD_LIVEPATCH2': completing unpatching transition
+$MOD_LIVEPATCH2: post_unpatch_callback: vmlinux
+livepatch: '$MOD_LIVEPATCH2': unpatching complete
+% rmmod $MOD_LIVEPATCH2"
+fi
 
 start_test "sysfs test replace enabled"
 

-- 
2.54.0