[PATCH v7 for-next 6/8] selftests/livepatch: Add provides/obsoletes test scenarios
From: Yafang Shao <hidden>
Date: 2026-08-25 11:47:31
Subsystem:
kernel selftest framework, live patching, the rest · Maintainers:
Shuah Khan, Shuah Khan, Josh Poimboeuf, Jiri Kosina, Miroslav Benes, Petr Mladek, Linus Torvalds
Now that the legacy "replace" field has been replaced by the provides/obsoletes mechanism, add test scenarios to verify the new behavior. Fill in the #else branches of the test modules that were left as TODO placeholders in the previous patch: - test_klp_atomic_replace.c gains provides and obsoletes module parameters for the provides/obsoletes based tests. - test_klp_callbacks_demo2.c gains a provides module parameter. - test_klp_livepatch.c gains a provides module parameter so that it can be loaded with a specific provides id for coexistence tests. - test_klp_state.c and test_klp_state2.c add a comment in the #else branch noting that provides=0 (the default) is equivalent to the previous .replace=true behavior. Add test-provides.sh with four test scenarios: 1. provides=0 replaces provides=0: two livepatches with provides=0 that modify different functions; the second replaces the first. 2. Same provides replaces: two livepatches with provides=1 that modify different functions; the second replaces the first. 3. Obsoletes replaces: a livepatch with provides=2 and obsoletes=[1] replaces a livepatch with provides=1. The provides/obsoletes sysfs values are verified. 4. provides=0 coexists with provides=1: two livepatches with different provides ids that modify different functions coexist, verifying that provides=0 does not replace a patch with a different provides id. The provides/obsoletes based tests only run on kernels that no longer support the legacy "replace" attribute. Assisted-by: Comagic:DeepSeek-V4-Flash Signed-off-by: Yafang Shao <redacted> --- tools/testing/selftests/livepatch/Makefile | 3 +- .../livepatch/test-provides-obsoletes.sh | 174 ++++++++++++++++++ .../test_modules/test_klp_atomic_replace.c | 22 ++- .../test_modules/test_klp_callbacks_demo2.c | 12 +- .../test_modules/test_klp_livepatch.c | 9 + .../livepatch/test_modules/test_klp_state.c | 5 +- .../livepatch/test_modules/test_klp_state2.c | 5 +- 7 files changed, 205 insertions(+), 25 deletions(-) create mode 100755 tools/testing/selftests/livepatch/test-provides-obsoletes.sh
diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
index a080eb54a215..38f98594d883 100644
--- a/tools/testing/selftests/livepatch/Makefile
+++ b/tools/testing/selftests/livepatch/Makefile@@ -11,7 +11,8 @@ TEST_PROGS := \ test-ftrace.sh \ test-sysfs.sh \ test-syscall.sh \ - test-kprobe.sh + test-kprobe.sh \ + test-provides-obsoletes.sh TEST_FILES := settings
diff --git a/tools/testing/selftests/livepatch/test-provides-obsoletes.sh b/tools/testing/selftests/livepatch/test-provides-obsoletes.sh
new file mode 100755
index 000000000000..2707457b9133
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test-provides-obsoletes.sh@@ -0,0 +1,174 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2026 Yafang Shao <laoar.shao@gmail.com> + +. $(dirname $0)/functions.sh + +MOD_ATOMIC=test_klp_atomic_replace +MOD_LIVEPATCH=test_klp_livepatch + +setup_config + +detect_replace_attr + +# The provides/obsoletes based tests only run on kernels that no longer +# support the legacy "replace" attribute. +if [[ "$HAS_REPLACE_ATTR" == "1" ]]; then + echo "SKIP: kernel still supports the legacy replace attribute" + exit $ksft_skip +fi + + +# - load a livepatch with provides=0 (cmdline), then another with +# provides=0 (meminfo). The second replaces the first (same provides). +# - unload the remaining livepatch + +start_test "provides 0 replaces provides 0" + +load_lp $MOD_LIVEPATCH provides=0 +load_lp $MOD_ATOMIC provides=0 + +check_sysfs_value "$MOD_ATOMIC" "enabled" "1" + +disable_lp $MOD_ATOMIC +unload_lp $MOD_ATOMIC +unload_lp $MOD_LIVEPATCH + +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko provides=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: '$MOD_LIVEPATCH': patching complete +% insmod test_modules/$MOD_ATOMIC.ko provides=0 +livepatch: enabling patch '$MOD_ATOMIC' +livepatch: '$MOD_ATOMIC': initializing patching transition +livepatch: '$MOD_ATOMIC': starting patching transition +livepatch: '$MOD_ATOMIC': completing patching transition +livepatch: '$MOD_ATOMIC': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_ATOMIC/enabled +livepatch: '$MOD_ATOMIC': initializing unpatching transition +livepatch: '$MOD_ATOMIC': starting unpatching transition +livepatch: '$MOD_ATOMIC': completing unpatching transition +livepatch: '$MOD_ATOMIC': unpatching complete +% rmmod $MOD_ATOMIC +% rmmod $MOD_LIVEPATCH" + + +# - load a livepatch with provides=1 (cmdline), then another with +# provides=1 (meminfo). The second replaces the first (same provides). +# - unload the remaining livepatch + +start_test "same provides replaces" + +load_lp $MOD_LIVEPATCH provides=1 +load_lp $MOD_ATOMIC provides=1 + +check_sysfs_value "$MOD_ATOMIC" "enabled" "1" + +disable_lp $MOD_ATOMIC +unload_lp $MOD_ATOMIC +unload_lp $MOD_LIVEPATCH + +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko provides=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: '$MOD_LIVEPATCH': patching complete +% insmod test_modules/$MOD_ATOMIC.ko provides=1 +livepatch: enabling patch '$MOD_ATOMIC' +livepatch: '$MOD_ATOMIC': initializing patching transition +livepatch: '$MOD_ATOMIC': starting patching transition +livepatch: '$MOD_ATOMIC': completing patching transition +livepatch: '$MOD_ATOMIC': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_ATOMIC/enabled +livepatch: '$MOD_ATOMIC': initializing unpatching transition +livepatch: '$MOD_ATOMIC': starting unpatching transition +livepatch: '$MOD_ATOMIC': completing unpatching transition +livepatch: '$MOD_ATOMIC': unpatching complete +% rmmod $MOD_ATOMIC +% rmmod $MOD_LIVEPATCH" + + +# - load a livepatch with provides=1 (cmdline), then another with +# provides=2 and obsoletes=[1] (meminfo). The second replaces the +# first (obsoletes contains the first patch's provides id). +# - verify the provides/obsoletes sysfs values +# - unload the remaining livepatch + +start_test "obsoletes replaces" + +load_lp $MOD_LIVEPATCH provides=1 +load_lp $MOD_ATOMIC provides=2 obsoletes=1 + +check_sysfs_value "$MOD_ATOMIC" "provides" "2" +check_sysfs_value "$MOD_ATOMIC" "obsoletes" "1" + +disable_lp $MOD_ATOMIC +unload_lp $MOD_ATOMIC +unload_lp $MOD_LIVEPATCH + +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko provides=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: '$MOD_LIVEPATCH': patching complete +% insmod test_modules/$MOD_ATOMIC.ko provides=2 obsoletes=1 +livepatch: enabling patch '$MOD_ATOMIC' +livepatch: '$MOD_ATOMIC': initializing patching transition +livepatch: '$MOD_ATOMIC': starting patching transition +livepatch: '$MOD_ATOMIC': completing patching transition +livepatch: '$MOD_ATOMIC': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_ATOMIC/enabled +livepatch: '$MOD_ATOMIC': initializing unpatching transition +livepatch: '$MOD_ATOMIC': starting unpatching transition +livepatch: '$MOD_ATOMIC': completing unpatching transition +livepatch: '$MOD_ATOMIC': unpatching complete +% rmmod $MOD_ATOMIC +% rmmod $MOD_LIVEPATCH" + + +# - load two livepatches with different provides ids that modify +# different functions and verify that they coexist +# - in particular, verify that provides=0 does NOT replace a patch +# with a different provides id +# - unload both livepatches + +start_test "provides 0 coexists with provides 1" + +load_lp $MOD_LIVEPATCH provides=0 +load_lp $MOD_ATOMIC provides=1 + +disable_lp $MOD_LIVEPATCH +unload_lp $MOD_LIVEPATCH +disable_lp $MOD_ATOMIC +unload_lp $MOD_ATOMIC + +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko provides=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: '$MOD_LIVEPATCH': patching complete +% insmod test_modules/$MOD_ATOMIC.ko provides=1 +livepatch: enabling patch '$MOD_ATOMIC' +livepatch: '$MOD_ATOMIC': initializing patching transition +livepatch: '$MOD_ATOMIC': starting patching transition +livepatch: '$MOD_ATOMIC': completing patching transition +livepatch: '$MOD_ATOMIC': patching complete +% echo 0 > /sys/kernel/livepatch/$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 $MOD_LIVEPATCH +% echo 0 > /sys/kernel/livepatch/$MOD_ATOMIC/enabled +livepatch: '$MOD_ATOMIC': initializing unpatching transition +livepatch: '$MOD_ATOMIC': starting unpatching transition +livepatch: '$MOD_ATOMIC': completing unpatching transition +livepatch: '$MOD_ATOMIC': unpatching complete +% rmmod $MOD_ATOMIC" + +exit 0
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c b/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
index 4b3ed17886e7..b0ed924eeeed 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c@@ -12,10 +12,15 @@ static int replace; module_param(replace, int, 0644); MODULE_PARM_DESC(replace, "replace (default=0)"); #else -/* - * TODO: Add provides/obsoletes module parameters for the - * provides/obsoletes based tests (to be added later). - */ +static unsigned int provides; +module_param(provides, uint, 0644); +MODULE_PARM_DESC(provides, "provides id (default=0)"); + +#define KLP_MAX_OBSOLETES 16 +static unsigned int obsoletes[KLP_MAX_OBSOLETES]; +static int nr_obsoletes; +module_param_array(obsoletes, uint, &nr_obsoletes, 0644); +MODULE_PARM_DESC(obsoletes, "obsoletes provides ids"); #endif #include <linux/seq_file.h>
@@ -53,10 +58,11 @@ static int test_klp_atomic_replace_init(void) #ifdef KLP_HAS_REPLACE patch.replace = replace; #else - /* - * TODO: Set provides/obsoletes from the module parameters - * for the provides/obsoletes based tests (to be added later). - */ + patch.provides = provides; + if (nr_obsoletes > 0) { + patch.obsoletes = obsoletes; + patch.nr_obsoletes = nr_obsoletes; + } #endif return klp_enable_patch(&patch); }
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
index 135da6d4d882..a0e7b7d1e198 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c@@ -12,10 +12,9 @@ static int replace; module_param(replace, int, 0644); MODULE_PARM_DESC(replace, "replace (default=0)"); #else -/* - * TODO: Add provides/obsoletes module parameters for the - * provides/obsoletes based tests (to be added later). - */ +static unsigned int provides; +module_param(provides, uint, 0644); +MODULE_PARM_DESC(provides, "provides id (default=0)"); #endif static const char *const module_state[] = {
@@ -89,10 +88,7 @@ static int test_klp_callbacks_demo2_init(void) #ifdef KLP_HAS_REPLACE patch.replace = replace; #else - /* - * TODO: Set provides/obsoletes from the module parameters - * for the provides/obsoletes based tests (to be added later). - */ + patch.provides = provides; #endif return klp_enable_patch(&patch); }
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c b/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
index aff08199de71..fa2bc6ec921d 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c@@ -7,6 +7,12 @@ #include <linux/kernel.h> #include <linux/livepatch.h> +#ifndef KLP_HAS_REPLACE +static unsigned int provides; +module_param(provides, uint, 0644); +MODULE_PARM_DESC(provides, "provides id (default=0)"); +#endif + #include <linux/seq_file.h> static int livepatch_cmdline_proc_show(struct seq_file *m, void *v) {
@@ -36,6 +42,9 @@ static struct klp_patch patch = { static int test_klp_livepatch_init(void) { +#ifndef KLP_HAS_REPLACE + patch.provides = provides; +#endif return klp_enable_patch(&patch); }
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_state.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
index 3492472e5d07..313401a5506e 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c@@ -145,10 +145,7 @@ static struct klp_patch patch = { #ifdef KLP_HAS_REPLACE .replace = true, #else -/* - * TODO: Add provides/obsoletes module parameters for the - * provides/obsoletes based tests (to be added later). - */ + /* provides=0 by default, replaces all provides=0 patches */ #endif };
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
index 8160b565a659..1afc2cabc39d 100644
--- a/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c@@ -174,10 +174,7 @@ static struct klp_patch patch = { #ifdef KLP_HAS_REPLACE .replace = true, #else -/* - * TODO: Add provides/obsoletes module parameters for the - * provides/obsoletes based tests (to be added later). - */ + /* provides=0 by default, replaces all provides=0 patches */ #endif };
--
2.52.0