[PATCH v5 0/6] kselftests: livepatch: Adapt tests to be executed on 4.12 kernels

[PATCH v5 0/6] kselftests: livepatch: Adapt tests to be executed on 4.12 kernels

[Marcos Paulo de Souza]

This is the fifth version of the patchset, which fixes the last Sashiko
comment, about overwriting MOD_LIVEPATCH global variable and using a
local variable to avoid module load clashing when an older kernel
don't support some sysfs attributes.

Original cover-letter:
These patches don't really change how the patches are run, just skip
some tests on kernels that don't support a feature (like kprobe and
livepatched living together) or when a livepatch sysfs attribute is
missing.

These patches are based on printk/for-next branch.

Please review! Thanks!

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
Changes in v5:
- Edit the last three patches to avoid overwriting MOD_LIVEPATCH
  variable, using a local variable. This fixed the last Sashiko report.
- Link to v4: https://patch.msgid.link/20260429-lp-tests-old-fixes-v4-0-59b9741989d0@suse.com

Changes in v4:
- Patch 5 was changed in order to address a comment made by Sashiko, where
  subsequent tests rewrite the variables that contain the modules being loaded.
- Link to v3: https://patch.msgid.link/20260427-lp-tests-old-fixes-v3-0-ccf3c90f744c@suse.com

Changes in v3:
- Patch 1 was changed to reorganize the ifdeffery to handle multiple archs syscall wrapper (Miroslav)
- Patch 3 was changed to rework the commit message and to address function naming (Joe)
- Patches 4, 5 and 6 where had the commit messages to include the kernel version where
  the given sysfs attributes were included (Petr Mladek)
- Link to v2: https://patch.msgid.link/20260413-lp-tests-old-fixes-v2-0-367c7cb5006f@suse.com

Changes in v2:
- Patch descriptions were changed to remove "test-X", since it was polluting the commit subjects (Miroslav Benes)
- Patch 8 was dropped since it was checking for a message from an out-of-tree patch. (Petr Mladek)
- Patch 3 was dropped as should be treated as expected failure for older kernels. (Petr Mladek)
- Patch 2 was changed to use y/n instead of 1/0, since it's more natural to use it.
- Patch 1 was changed to handle ppc and loongson, and error out if dealing with a different architecture that sets
  CONFIG_ARCH_HAS_SYSCALL_WRAPPER and haven't changed the test to include the proper wrapper prefix.
- Patch 4 was changed to invert the return of the bash function to return 1 in failure, like
  a normal bash function (Joe Lawrence)
- Patches 5, 6 an 7 were changed to not split the tests, but to only run the tests
  when the attribute were present (Miroslav Benes)
- Link to v1: https://patch.msgid.link/20260313-lp-tests-old-fixes-v1-0-71ac6dfb3253@suse.com

---
Marcos Paulo de Souza (6):
      selftests: livepatch: Check for ARCH_HAS_SYSCALL_WRAPPER config
      selftests: livepatch: Replace true/false module parameter by y/n
      selftests: livepatch: Introduce does_sysfs_exist function
      selftests: livepatch: Check if patched sysfs attribute exists
      selftests: livepatch: Check if replace sysfs attribute exists
      selftests: livepatch: Check if stack_order sysfs attribute exists

 tools/testing/selftests/livepatch/functions.sh     |  10 +
 tools/testing/selftests/livepatch/test-kprobe.sh   |   8 +-
 tools/testing/selftests/livepatch/test-sysfs.sh    | 219 +++++++++++----------
 .../livepatch/test_modules/test_klp_syscall.c      |  27 ++-
 4 files changed, 153 insertions(+), 111 deletions(-)
---
base-commit: 712c0756828becbfc629ff8d8b82deff5d1115e4
change-id: 20260309-lp-tests-old-fixes-f955abc8ec27

Best regards,
--  
Marcos Paulo de Souza <mpdesouza@suse.com>

[PATCH v5 1/6] selftests: livepatch: Check for ARCH_HAS_SYSCALL_WRAPPER config

[Marcos Paulo de Souza]

Older kernels that lack CONFIG_ARCH_HAS_SYSCALL_WRAPPER config don't
have any prefixes for their syscalls. The same applies to current
powerpc and loongarch, covering all currently supported architectures
that support livepatch.

The other supported architectures have specific prefixes, so error out
when a new architecture adds livepatch support with wrappers but didn't
update the test to include it.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 .../livepatch/test_modules/test_klp_syscall.c      | 27 +++++++++++++++-------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
index dd802783ea84..0630ffd9d9a1 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
@@ -12,15 +12,26 @@
 #include <linux/slab.h>
 #include <linux/livepatch.h>
 
-#if defined(__x86_64__)
-#define FN_PREFIX __x64_
-#elif defined(__s390x__)
-#define FN_PREFIX __s390x_
-#elif defined(__aarch64__)
-#define FN_PREFIX __arm64_
+/*
+ * Before CONFIG_ARCH_HAS_SYSCALL_WRAPPER was introduced there were no
+ * prefixes for system calls.
+ * powerpc set this config based on configs, so it can be enabled or not.
+ */
+#if defined(CONFIG_ARCH_HAS_SYSCALL_WRAPPER)
+  #if defined(__x86_64__)
+    #define FN_PREFIX __x64_
+  #elif defined(__s390x__)
+    #define FN_PREFIX __s390x_
+  #elif defined(__aarch64__)
+    #define FN_PREFIX __arm64_
+  #elif defined(__powerpc__)
+    #define FN_PREFIX
+  #else
+    #error "Missing syscall wrapper for the given architecture."
+  #endif
 #else
-/* powerpc does not select ARCH_HAS_SYSCALL_WRAPPER */
-#define FN_PREFIX
+  /* Do not set a prefix for architectures that do not enable wrappers. */
+  #define FN_PREFIX
 #endif
 
 /* Protects klp_pids */

-- 
2.54.0

[PATCH v5 2/6] selftests: livepatch: Replace true/false module parameter by y/n

[Marcos Paulo de Souza]

Older kernels don't support true/false for boolean module parameters
because they lack commit 0d6ea3ac94ca
("lib/kstrtox.c: add "false"/"true" support to kstrtobool()"). Replace
true/false by y/n so the test module can be loaded on older kernels.

No functional changes.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 tools/testing/selftests/livepatch/test-kprobe.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test-kprobe.sh b/tools/testing/selftests/livepatch/test-kprobe.sh
index b67dfad03d97..7ced4082cff3 100755
--- a/tools/testing/selftests/livepatch/test-kprobe.sh
+++ b/tools/testing/selftests/livepatch/test-kprobe.sh
@@ -20,11 +20,11 @@ start_test "livepatch interaction with kprobed function with post_handler"
 
 echo 1 > "$SYSFS_KPROBES_DIR/enabled"
 
-load_mod $MOD_KPROBE has_post_handler=true
+load_mod $MOD_KPROBE has_post_handler=y
 load_failing_mod $MOD_LIVEPATCH
 unload_mod $MOD_KPROBE
 
-check_result "% insmod test_modules/test_klp_kprobe.ko has_post_handler=true
+check_result "% insmod test_modules/test_klp_kprobe.ko has_post_handler=y
 % insmod test_modules/$MOD_LIVEPATCH.ko
 livepatch: enabling patch '$MOD_LIVEPATCH'
 livepatch: '$MOD_LIVEPATCH': initializing patching transition
@@ -39,14 +39,14 @@ insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: Device or
 
 start_test "livepatch interaction with kprobed function without post_handler"
 
-load_mod $MOD_KPROBE has_post_handler=false
+load_mod $MOD_KPROBE has_post_handler=n
 load_lp $MOD_LIVEPATCH
 
 unload_mod $MOD_KPROBE
 disable_lp $MOD_LIVEPATCH
 unload_lp $MOD_LIVEPATCH
 
-check_result "% insmod test_modules/test_klp_kprobe.ko has_post_handler=false
+check_result "% insmod test_modules/test_klp_kprobe.ko has_post_handler=n
 % insmod test_modules/$MOD_LIVEPATCH.ko
 livepatch: enabling patch '$MOD_LIVEPATCH'
 livepatch: '$MOD_LIVEPATCH': initializing patching transition

-- 
2.54.0

[PATCH v5 3/6] selftests: livepatch: Introduce does_sysfs_exist function

[Marcos Paulo de Souza]

Returns true if the livepatch sysfs attribute exists, and false otherwise.
This new function will be used in the next patches.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 tools/testing/selftests/livepatch/functions.sh | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
index 8ec0cb64ad94..2bc50271729c 100644
--- a/tools/testing/selftests/livepatch/functions.sh
+++ b/tools/testing/selftests/livepatch/functions.sh
@@ -339,6 +339,16 @@ function check_result {
 	fi
 }
 
+# does_sysfs_exist(modname, attr) - check sysfs attribute existence
+#	modname - livepatch module creating the sysfs interface
+#	attr - attribute name to be checked
+function does_sysfs_exist() {
+	local mod="$1"; shift
+	local attr="$1"; shift
+
+	[[ -f "$SYSFS_KLP_DIR/$mod/$attr" ]]
+}
+
 # check_sysfs_rights(modname, rel_path, expected_rights) - check sysfs
 # path permissions
 #	modname - livepatch module creating the sysfs interface

-- 
2.54.0

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

[Marcos Paulo de Souza]

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

[PATCH v5 5/6] selftests: livepatch: Check if replace sysfs attribute exists

[Marcos Paulo de Souza]

The commit adb68ed26a3e ("livepatch: Add "replace" sysfs attribute"),
merged in v6.11, 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.

While at it, create a local variable to hold the module name to be
tested, instead of overwriting MOD_LIVEPATCH.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 tools/testing/selftests/livepatch/test-sysfs.sh | 101 +++++++++++++-----------
 1 file changed, 54 insertions(+), 47 deletions(-)

diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index 7fa2223f9533..fed656021271 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_exist "$MOD_LIVEPATCH/vmlinux" "patched"; then
 	HAS_PATCH_ATTR=1
 fi
 
+if does_sysfs_exist "$MOD_LIVEPATCH" "replace"; then
+	check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
+	HAS_REPLACE_ATTR=1
+fi
+
 disable_lp $MOD_LIVEPATCH
 
 unload_lp $MOD_LIVEPATCH
@@ -95,52 +100,54 @@ livepatch: '$MOD_LIVEPATCH2': unpatching complete
 % rmmod $MOD_LIVEPATCH2"
 fi
 
-start_test "sysfs test replace enabled"
-
-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"
-
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
-
-check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=1
-livepatch: enabling patch '$MOD_LIVEPATCH'
-livepatch: '$MOD_LIVEPATCH': initializing patching transition
-livepatch: '$MOD_LIVEPATCH': starting patching transition
-livepatch: '$MOD_LIVEPATCH': completing patching transition
-livepatch: '$MOD_LIVEPATCH': patching complete
-% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH/enabled
-livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
-livepatch: '$MOD_LIVEPATCH': starting unpatching transition
-livepatch: '$MOD_LIVEPATCH': completing unpatching transition
-livepatch: '$MOD_LIVEPATCH': unpatching complete
-% rmmod $MOD_LIVEPATCH"
-
-start_test "sysfs test replace disabled"
-
-load_lp $MOD_LIVEPATCH replace=0
-
-check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
-check_sysfs_value  "$MOD_LIVEPATCH" "replace" "0"
-
-disable_lp $MOD_LIVEPATCH
-unload_lp $MOD_LIVEPATCH
-
-check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=0
-livepatch: enabling patch '$MOD_LIVEPATCH'
-livepatch: '$MOD_LIVEPATCH': initializing patching transition
-livepatch: '$MOD_LIVEPATCH': starting patching transition
-livepatch: '$MOD_LIVEPATCH': completing patching transition
-livepatch: '$MOD_LIVEPATCH': patching complete
-% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH/enabled
-livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
-livepatch: '$MOD_LIVEPATCH': starting unpatching transition
-livepatch: '$MOD_LIVEPATCH': completing unpatching transition
-livepatch: '$MOD_LIVEPATCH': unpatching complete
-% rmmod $MOD_LIVEPATCH"
+if [[ "$HAS_REPLACE_ATTR" == "1" ]]; then
+	start_test "sysfs test replace enabled"
+
+	MOD_ATOMIC_REPLACE=test_klp_atomic_replace
+	load_lp $MOD_ATOMIC_REPLACE replace=1
+
+	check_sysfs_rights "$MOD_ATOMIC_REPLACE" "replace" "-r--r--r--"
+	check_sysfs_value  "$MOD_ATOMIC_REPLACE" "replace" "1"
+
+	disable_lp $MOD_ATOMIC_REPLACE
+	unload_lp $MOD_ATOMIC_REPLACE
+
+	check_result "% insmod test_modules/$MOD_ATOMIC_REPLACE.ko replace=1
+livepatch: enabling patch '$MOD_ATOMIC_REPLACE'
+livepatch: '$MOD_ATOMIC_REPLACE': initializing patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': starting patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': completing patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': patching complete
+% echo 0 > $SYSFS_KLP_DIR/$MOD_ATOMIC_REPLACE/enabled
+livepatch: '$MOD_ATOMIC_REPLACE': initializing unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': starting unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': completing unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': unpatching complete
+% rmmod $MOD_ATOMIC_REPLACE"
+
+	start_test "sysfs test replace disabled"
+
+	load_lp $MOD_ATOMIC_REPLACE replace=0
+
+	check_sysfs_rights "$MOD_ATOMIC_REPLACE" "replace" "-r--r--r--"
+	check_sysfs_value  "$MOD_ATOMIC_REPLACE" "replace" "0"
+
+	disable_lp $MOD_ATOMIC_REPLACE
+	unload_lp $MOD_ATOMIC_REPLACE
+
+	check_result "% insmod test_modules/$MOD_ATOMIC_REPLACE.ko replace=0
+livepatch: enabling patch '$MOD_ATOMIC_REPLACE'
+livepatch: '$MOD_ATOMIC_REPLACE': initializing patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': starting patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': completing patching transition
+livepatch: '$MOD_ATOMIC_REPLACE': patching complete
+% echo 0 > $SYSFS_KLP_DIR/$MOD_ATOMIC_REPLACE/enabled
+livepatch: '$MOD_ATOMIC_REPLACE': initializing unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': starting unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': completing unpatching transition
+livepatch: '$MOD_ATOMIC_REPLACE': unpatching complete
+% rmmod $MOD_ATOMIC_REPLACE"
+fi
 
 start_test "sysfs test stack_order value"
 

-- 
2.54.0

[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@suse.com>
---
 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

Re: [PATCH v5 0/6] kselftests: livepatch: Adapt tests to be executed on 4.12 kernels

[Joe Lawrence]

On 5/4/26 2:34 PM, Marcos Paulo de Souza wrote:
> This is the fifth version of the patchset, which fixes the last Sashiko
> comment, about overwriting MOD_LIVEPATCH global variable and using a
> local variable to avoid module load clashing when an older kernel
> don't support some sysfs attributes.
> 
> Original cover-letter:
> These patches don't really change how the patches are run, just skip
> some tests on kernels that don't support a feature (like kprobe and
> livepatched living together) or when a livepatch sysfs attribute is
> missing.
> 
> These patches are based on printk/for-next branch.
> 
> Please review! Thanks!
> 
> Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
> ---
> Changes in v5:
> - Edit the last three patches to avoid overwriting MOD_LIVEPATCH
>   variable, using a local variable. This fixed the last Sashiko report.
> - Link to v4: https://patch.msgid.link/20260429-lp-tests-old-fixes-v4-0-59b9741989d0@suse.com
> 
> Changes in v4:
> - Patch 5 was changed in order to address a comment made by Sashiko, where
>   subsequent tests rewrite the variables that contain the modules being loaded.
> - Link to v3: https://patch.msgid.link/20260427-lp-tests-old-fixes-v3-0-ccf3c90f744c@suse.com
> 
> Changes in v3:
> - Patch 1 was changed to reorganize the ifdeffery to handle multiple archs syscall wrapper (Miroslav)
> - Patch 3 was changed to rework the commit message and to address function naming (Joe)
> - Patches 4, 5 and 6 where had the commit messages to include the kernel version where
>   the given sysfs attributes were included (Petr Mladek)
> - Link to v2: https://patch.msgid.link/20260413-lp-tests-old-fixes-v2-0-367c7cb5006f@suse.com
> 
> Changes in v2:
> - Patch descriptions were changed to remove "test-X", since it was polluting the commit subjects (Miroslav Benes)
> - Patch 8 was dropped since it was checking for a message from an out-of-tree patch. (Petr Mladek)
> - Patch 3 was dropped as should be treated as expected failure for older kernels. (Petr Mladek)
> - Patch 2 was changed to use y/n instead of 1/0, since it's more natural to use it.
> - Patch 1 was changed to handle ppc and loongson, and error out if dealing with a different architecture that sets
>   CONFIG_ARCH_HAS_SYSCALL_WRAPPER and haven't changed the test to include the proper wrapper prefix.
> - Patch 4 was changed to invert the return of the bash function to return 1 in failure, like
>   a normal bash function (Joe Lawrence)
> - Patches 5, 6 an 7 were changed to not split the tests, but to only run the tests
>   when the attribute were present (Miroslav Benes)
> - Link to v1: https://patch.msgid.link/20260313-lp-tests-old-fixes-v1-0-71ac6dfb3253@suse.com
> 
> ---
> Marcos Paulo de Souza (6):
>       selftests: livepatch: Check for ARCH_HAS_SYSCALL_WRAPPER config
>       selftests: livepatch: Replace true/false module parameter by y/n
>       selftests: livepatch: Introduce does_sysfs_exist function
>       selftests: livepatch: Check if patched sysfs attribute exists
>       selftests: livepatch: Check if replace sysfs attribute exists
>       selftests: livepatch: Check if stack_order sysfs attribute exists
> 
>  tools/testing/selftests/livepatch/functions.sh     |  10 +
>  tools/testing/selftests/livepatch/test-kprobe.sh   |   8 +-
>  tools/testing/selftests/livepatch/test-sysfs.sh    | 219 +++++++++++----------
>  .../livepatch/test_modules/test_klp_syscall.c      |  27 ++-
>  4 files changed, 153 insertions(+), 111 deletions(-)
> ---
> base-commit: 712c0756828becbfc629ff8d8b82deff5d1115e4
> change-id: 20260309-lp-tests-old-fixes-f955abc8ec27
> 

Acked-by: Joe Lawrence <joe.lawrence@redhat.com>

FWIW, I tried this out on 4.18.0-372.137.1.el8_6.x86_64, the oldest
kernel we're supporting for livepatching at the momement, and the modern
selftests + Marcos's patchset happily ran without any problems.

-- 
Joe

Re: [PATCH v5 0/6] kselftests: livepatch: Adapt tests to be executed on 4.12 kernels

[Petr Mladek]

On Mon 2026-05-04 15:34:41, Marcos Paulo de Souza wrote:
> This is the fifth version of the patchset, which fixes the last Sashiko
> comment, about overwriting MOD_LIVEPATCH global variable and using a
> local variable to avoid module load clashing when an older kernel
> don't support some sysfs attributes.
> 
> Original cover-letter:
> These patches don't really change how the patches are run, just skip
> some tests on kernels that don't support a feature (like kprobe and
> livepatched living together) or when a livepatch sysfs attribute is
> missing.
> 
> ---
> Marcos Paulo de Souza (6):
>       selftests: livepatch: Check for ARCH_HAS_SYSCALL_WRAPPER config
>       selftests: livepatch: Replace true/false module parameter by y/n
>       selftests: livepatch: Introduce does_sysfs_exist function
>       selftests: livepatch: Check if patched sysfs attribute exists
>       selftests: livepatch: Check if replace sysfs attribute exists
>       selftests: livepatch: Check if stack_order sysfs attribute exists
> 
>  tools/testing/selftests/livepatch/functions.sh     |  10 +
>  tools/testing/selftests/livepatch/test-kprobe.sh   |   8 +-
>  tools/testing/selftests/livepatch/test-sysfs.sh    | 219 +++++++++++----------
>  .../livepatch/test_modules/test_klp_syscall.c      |  27 ++-
>  4 files changed, 153 insertions(+), 111 deletions(-)

For the entire patchset:

Reviewed-by: Petr Mladek <pmladek@suse.com>

It seems to be ready for linux-next.

Best Regards,
Petr

Re: [PATCH v5 0/6] kselftests: livepatch: Adapt tests to be executed on 4.12 kernels

[Petr Mladek]

On Mon 2026-05-04 15:34:41, Marcos Paulo de Souza wrote:
> This is the fifth version of the patchset, which fixes the last Sashiko
> comment, about overwriting MOD_LIVEPATCH global variable and using a
> local variable to avoid module load clashing when an older kernel
> don't support some sysfs attributes.
> 
> Original cover-letter:
> These patches don't really change how the patches are run, just skip
> some tests on kernels that don't support a feature (like kprobe and
> livepatched living together) or when a livepatch sysfs attribute is
> missing.
> 
> These patches are based on printk/for-next branch.
> 
> Please review! Thanks!
> 
> Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
> ---
> Changes in v5:
> - Edit the last three patches to avoid overwriting MOD_LIVEPATCH
>   variable, using a local variable. This fixed the last Sashiko report.
> - Link to v4: https://patch.msgid.link/20260429-lp-tests-old-fixes-v4-0-59b9741989d0@suse.com

JFYI, the patchset has been pushed into livepatch.git,
branch for-7.2-selftests.

Best Regards,
Petr