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[PATCH 5/8] selftests: livepatch: sysfs: Split tests of replace attribute

Marcos Paulo de Souza posted 8 patches 3 weeks, 3 days ago
[PATCH 5/8] selftests: livepatch: sysfs: Split tests of replace attribute
Posted by Marcos Paulo de Souza 3 weeks, 3 days ago 
In order to run the selftests on older kernels, split the sysfs tests to
another file, making it able to skip the tests when the attributes
don't exists.

No functional changes.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
---
 tools/testing/selftests/livepatch/Makefile         |  1 +
 .../selftests/livepatch/test-sysfs-replace-attr.sh | 75 ++++++++++++++++++++++
 tools/testing/selftests/livepatch/test-sysfs.sh    | 48 --------------
 3 files changed, 76 insertions(+), 48 deletions(-)

diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
index a080eb54a215d..b95aa6e78a273 100644
--- a/tools/testing/selftests/livepatch/Makefile
+++ b/tools/testing/selftests/livepatch/Makefile
@@ -10,6 +10,7 @@ TEST_PROGS := \
 	test-state.sh \
 	test-ftrace.sh \
 	test-sysfs.sh \
+	test-sysfs-replace-attr.sh \
 	test-syscall.sh \
 	test-kprobe.sh
 
diff --git a/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh b/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh
new file mode 100755
index 0000000000000..d1051211fe320
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh
@@ -0,0 +1,75 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2022 Song Liu <song@kernel.org>
+
+. $(dirname $0)/functions.sh
+
+MOD_LIVEPATCH=test_klp_livepatch
+
+setup_config
+
+# - load a livepatch and verifies the sysfs replace attribute exists
+
+start_test "check sysfs replace attribute"
+
+load_lp $MOD_LIVEPATCH
+
+check_sysfs_exists "$MOD_LIVEPATCH" "replace"
+file_exists=$?
+
+disable_lp $MOD_LIVEPATCH
+
+unload_lp $MOD_LIVEPATCH
+
+if [[ "$file_exists" == "0" ]]; then
+	skip "sysfs attribute doesn't exists."
+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 $MOD_LIVEPATCH"
+
+exit 0
diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index 58fe1d96997cd..0865a7959496a 100755
--- a/tools/testing/selftests/livepatch/test-sysfs.sh
+++ b/tools/testing/selftests/livepatch/test-sysfs.sh
@@ -20,7 +20,6 @@ check_sysfs_rights "$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--"
@@ -88,53 +87,6 @@ test_klp_callbacks_demo: post_unpatch_callback: vmlinux
 livepatch: 'test_klp_callbacks_demo': unpatching complete
 % rmmod test_klp_callbacks_demo"
 
-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"
-
 start_test "sysfs test stack_order value"
 
 load_lp $MOD_LIVEPATCH

-- 
2.52.0
Re: [PATCH 5/8] selftests: livepatch: sysfs: Split tests of replace attribute
Posted by Petr Mladek 2 weeks, 3 days ago 
On Fri 2026-03-13 17:58:36, Marcos Paulo de Souza wrote:
> In order to run the selftests on older kernels, split the sysfs tests to
> another file, making it able to skip the tests when the attributes
> don't exists.
> 
> No functional changes.
> 
> Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
> ---
>  tools/testing/selftests/livepatch/Makefile         |  1 +
>  .../selftests/livepatch/test-sysfs-replace-attr.sh | 75 ++++++++++++++++++++++
>  tools/testing/selftests/livepatch/test-sysfs.sh    | 48 --------------
>  3 files changed, 76 insertions(+), 48 deletions(-)
> 
> diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
> index a080eb54a215d..b95aa6e78a273 100644
> --- a/tools/testing/selftests/livepatch/Makefile
> +++ b/tools/testing/selftests/livepatch/Makefile
> @@ -10,6 +10,7 @@ TEST_PROGS := \
>  	test-state.sh \
>  	test-ftrace.sh \
>  	test-sysfs.sh \
> +	test-sysfs-replace-attr.sh \
>  	test-syscall.sh \
>  	test-kprobe.sh
>  
> diff --git a/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh b/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh
> new file mode 100755
> index 0000000000000..d1051211fe320
> --- /dev/null
> +++ b/tools/testing/selftests/livepatch/test-sysfs-replace-attr.sh
> @@ -0,0 +1,75 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (C) 2022 Song Liu <song@kernel.org>
> +
> +. $(dirname $0)/functions.sh
> +
> +MOD_LIVEPATCH=test_klp_livepatch
> +
> +setup_config
> +
> +# - load a livepatch and verifies the sysfs replace attribute exists
> +
> +start_test "check sysfs replace attribute"
> +
> +load_lp $MOD_LIVEPATCH
> +
> +check_sysfs_exists "$MOD_LIVEPATCH" "replace"
> +file_exists=$?
> +
> +disable_lp $MOD_LIVEPATCH
> +
> +unload_lp $MOD_LIVEPATCH
> +
> +if [[ "$file_exists" == "0" ]]; then
> +	skip "sysfs attribute doesn't exists."

Nit: I would write "is not supported by this kernel version"
     instead of "doesn't exist".

     I think that it better describes the situation.
     "doesn't exist" sounds more like an error description.

> +fi

This extra code is repeated in 6th and 7th patch as well.
It would be nice to hide it into some helper function
so that we could use here something like:

	check_sysfs_attr_or_skip "replace"

or

	if has_klp_sysfs_attr "replace" ; then
		skip "sysfs \"replace\" attribute is not supported"
	fi

Best Regards,
Petr
Re: [PATCH 5/8] selftests: livepatch: sysfs: Split tests of replace attribute
Posted by Miroslav Benes 2 weeks, 3 days ago 
On Fri, 13 Mar 2026, Marcos Paulo de Souza wrote:

> In order to run the selftests on older kernels, split the sysfs tests to
> another file, making it able to skip the tests when the attributes
> don't exists.
> 
> No functional changes.

The functional change is that the test does not run older kernels now so I 
would remove the line.

Anyway, I am not entirely happy with carving all three tests out of 
test-sysfs.sh to be honest. Wouldn't it be better to just hide them under 
"if check_sysfs_exists" condition and keep them here? You could make it 
more compact if you check for the sysfs attribute just before checking 
both permissions and values the first time it is accessed.

Miroslav

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