2023-10-31 21:11:36

by Marcos Paulo de Souza

Subject: [PATCH v3 0/3] livepatch: Move modules to selftests and add a new test

This patchset moves the current kernel testing livepatch modules from
lib/livepatches to tools/testing/selftest/livepatch/test_modules, and compiles
them as out-of-tree modules before testing.

There is also a new test being added. This new test exercises multiple processes
calling a syscall, while a livepatch patched the syscall.

Why this move is an improvement:
* The modules are now compiled as out-of-tree modules against the current
running kernel, making them capable of being tested on different systems with
newer or older kernels.
* Such approach now needs kernel-devel package to be installed, since they are
out-of-tree modules. These can be generated by running "make rpm-pkg" in the
kernel source.

What needs to be solved:
* Currently gen_tar only packages the resulting binaries of the tests, and not
the sources. For the current approach, the newly added modules would be
compiled and then packaged. It works when testing on a system with the same
kernel version. But it will fail when running on a machine with different kernel
version, since module was compiled against the kernel currently running.

This is not a new problem, just aligning the expectations. For the current
approach to be truly system agnostic gen_tar would need to include the module
and program sources to be compiled in the target systems.

I'm sending the patches now so it can be discussed before Plumbers.

Thanks in advance!
Marcos

To: Shuah Khan <[email protected]>
To: Jonathan Corbet <[email protected]>
To: Heiko Carstens <[email protected]>
To: Vasily Gorbik <[email protected]>
To: Alexander Gordeev <[email protected]>
To: Christian Borntraeger <[email protected]>
To: Sven Schnelle <[email protected]>
To: Josh Poimboeuf <[email protected]>
To: Jiri Kosina <[email protected]>
To: Miroslav Benes <[email protected]>
To: Petr Mladek <[email protected]>
To: Joe Lawrence <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Marcos Paulo de Souza <[email protected]>

Changes in v3:
* Rebased on top of v6.6-rc5
* The commits messages were improved (Thanks Petr!)
* Created TEST_GEN_MODS_DIR variable to point to a directly that contains kernel
modules, and adapt selftests to build it before running the test.
* Moved test_klp-call_getpid out of test_programs, since the gen_tar
would just copy the generated test programs to the livepatches dir,
and so scripts relying on test_programs/test_klp-call_getpid will fail.
* Added a module_param for klp_pids, describing it's usage.
* Simplified the call_getpid program to ignore the return of getpid syscall,
since we only want to make sure the process transitions correctly to the
patched stated
* The test-syscall.sh not prints a log message showing the number of remaining
processes to transition into to livepatched state, and check_output expects it
to be 0.
* Added MODULE_AUTHOR and MODULE_DESCRIPTION to test_klp_syscall.c

The v2 can be seen here:
https://lore.kernel.org/linux-kselftest/[email protected]/

---
Marcos Paulo de Souza (3):
kselftests: lib.mk: Add TEST_GEN_MODS_DIR variable
livepatch: Move tests from lib/livepatch to selftests/livepatch
selftests: livepatch: Test livepatching a heavily called syscall

Documentation/dev-tools/kselftest.rst | 4 +
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
lib/Kconfig.debug | 22 ----
lib/Makefile | 2 -
lib/livepatch/Makefile | 14 ---
tools/testing/selftests/lib.mk | 20 +++-
tools/testing/selftests/livepatch/Makefile | 5 +-
tools/testing/selftests/livepatch/README | 17 +--
tools/testing/selftests/livepatch/config | 1 -
tools/testing/selftests/livepatch/functions.sh | 34 +++---
.../testing/selftests/livepatch/test-callbacks.sh | 50 ++++-----
tools/testing/selftests/livepatch/test-ftrace.sh | 6 +-
.../testing/selftests/livepatch/test-livepatch.sh | 10 +-
.../selftests/livepatch/test-shadow-vars.sh | 2 +-
tools/testing/selftests/livepatch/test-state.sh | 18 ++--
tools/testing/selftests/livepatch/test-syscall.sh | 53 ++++++++++
tools/testing/selftests/livepatch/test-sysfs.sh | 6 +-
.../selftests/livepatch/test_klp-call_getpid.c | 44 ++++++++
.../selftests/livepatch/test_modules/Makefile | 20 ++++
.../test_modules}/test_klp_atomic_replace.c | 0
.../test_modules}/test_klp_callbacks_busy.c | 0
.../test_modules}/test_klp_callbacks_demo.c | 0
.../test_modules}/test_klp_callbacks_demo2.c | 0
.../test_modules}/test_klp_callbacks_mod.c | 0
.../livepatch/test_modules}/test_klp_livepatch.c | 0
.../livepatch/test_modules}/test_klp_shadow_vars.c | 0
.../livepatch/test_modules}/test_klp_state.c | 0
.../livepatch/test_modules}/test_klp_state2.c | 0
.../livepatch/test_modules}/test_klp_state3.c | 0
.../livepatch/test_modules/test_klp_syscall.c | 116 +++++++++++++++++++++
31 files changed, 325 insertions(+), 121 deletions(-)
---
base-commit: 6489bf2e1df1c84e9bcd4694029ff35b39fd3397
change-id: 20231031-send-lp-kselftests-4c917dcd4565

Best regards,
--
Marcos Paulo de Souza <[email protected]>

2023-10-31 21:12:25

by Marcos Paulo de Souza

Subject: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

The modules are being moved from lib/livepatch to
tools/testing/selftests/livepatch/test_modules.

This code moving will allow writing more complex tests, like for example an
userspace C code that will call a livepatched kernel function.

The modules are now built as out-of-tree
modules, but being part of the kernel source means they will be maintained.

Another advantage of the code moving is to be able to easily change,
debug and rebuild the tests by running make on the selftests/livepatch directory,
which is not currently possible since the modules on lib/livepatch are
build and installed using the "modules" target.

The current approach also keeps the ability to execute the tests manually by
executing the scripts inside selftests/livepatch directory, as it's currently
supported. If the modules are modified, they needed to be rebuilt before running
the scripts though.

The modules are built before running the selftests when using the
kselftest invocations:

make kselftest TARGETS=livepatch
or
make -C tools/testing/selftests/livepatch run_tests

Having the modules being built as out-of-modules requires changing the currently
used 'modprobe' by 'insmod' and adapt the test scripts that check for the kernel
message buffer.

As there aren't any modules being built on lib/livepatch, remove the
TEST_LIVEPATCH Kconfig and it's references.

Note: "make gen_tar" packages the pre-built binaries into the tarball.
It means that it will store the test modules pre-built for
the kernel running on the build host.

Note that these modules need not binary compatible with
the kernel built from the same sources. But the same
is true for other packaged selftest binaries.

The entire kernel sources are needed for rebuilding
the selftests on another system.

Signed-off-by: Marcos Paulo de Souza <[email protected]>
---
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
lib/Kconfig.debug | 22 ----------
lib/Makefile | 2 -
lib/livepatch/Makefile | 14 ------
tools/testing/selftests/livepatch/Makefile | 1 +
tools/testing/selftests/livepatch/README | 17 +++++---
tools/testing/selftests/livepatch/config | 1 -
tools/testing/selftests/livepatch/functions.sh | 34 ++++++---------
.../testing/selftests/livepatch/test-callbacks.sh | 50 +++++++++++-----------
tools/testing/selftests/livepatch/test-ftrace.sh | 6 +--
.../testing/selftests/livepatch/test-livepatch.sh | 10 ++---
.../selftests/livepatch/test-shadow-vars.sh | 2 +-
tools/testing/selftests/livepatch/test-state.sh | 18 ++++----
tools/testing/selftests/livepatch/test-sysfs.sh | 6 +--
.../selftests/livepatch/test_modules/Makefile | 19 ++++++++
.../test_modules}/test_klp_atomic_replace.c | 0
.../test_modules}/test_klp_callbacks_busy.c | 0
.../test_modules}/test_klp_callbacks_demo.c | 0
.../test_modules}/test_klp_callbacks_demo2.c | 0
.../test_modules}/test_klp_callbacks_mod.c | 0
.../livepatch/test_modules}/test_klp_livepatch.c | 0
.../livepatch/test_modules}/test_klp_shadow_vars.c | 0
.../livepatch/test_modules}/test_klp_state.c | 0
.../livepatch/test_modules}/test_klp_state2.c | 0
.../livepatch/test_modules}/test_klp_state3.c | 0
26 files changed, 89 insertions(+), 115 deletions(-)

diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index 438cd92e6080..9672b9f31710 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -885,4 +885,3 @@ CONFIG_ATOMIC64_SELFTEST=y
CONFIG_STRING_SELFTEST=y
CONFIG_TEST_BITOPS=m
CONFIG_TEST_BPF=m
-CONFIG_TEST_LIVEPATCH=m
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 1b8150e50f6a..a8a66264a72d 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -813,4 +813,3 @@ CONFIG_KPROBES_SANITY_TEST=m
CONFIG_PERCPU_TEST=m
CONFIG_ATOMIC64_SELFTEST=y
CONFIG_TEST_BPF=m
-CONFIG_TEST_LIVEPATCH=m
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index fa307f93fa2e..af67c5f5d031 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2862,28 +2862,6 @@ config TEST_MEMCAT_P

If unsure, say N.

-config TEST_LIVEPATCH
- tristate "Test livepatching"
- default n
- depends on DYNAMIC_DEBUG
- depends on LIVEPATCH
- depends on m
- help
- Test kernel livepatching features for correctness. The tests will
- load test modules that will be livepatched in various scenarios.
-
- To run all the livepatching tests:
-
- make -C tools/testing/selftests TARGETS=livepatch run_tests
-
- Alternatively, individual tests may be invoked:
-
- tools/testing/selftests/livepatch/test-callbacks.sh
- tools/testing/selftests/livepatch/test-livepatch.sh
- tools/testing/selftests/livepatch/test-shadow-vars.sh
-
- If unsure, say N.
-
config TEST_OBJAGG
tristate "Perform selftest on object aggreration manager"
default n
diff --git a/lib/Makefile b/lib/Makefile
index 740109b6e2c8..b96b280787ca 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -132,8 +132,6 @@ endif
obj-$(CONFIG_TEST_FPU) += test_fpu.o
CFLAGS_test_fpu.o += $(FPU_CFLAGS)

-obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/
-
# Some KUnit files (hooks.o) need to be built-in even when KUnit is a module,
# so we can't just use obj-$(CONFIG_KUNIT).
ifdef CONFIG_KUNIT
diff --git a/lib/livepatch/Makefile b/lib/livepatch/Makefile
deleted file mode 100644
index dcc912b3478f..000000000000
--- a/lib/livepatch/Makefile
+++ /dev/null
@@ -1,14 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-#
-# Makefile for livepatch test code.
-
-obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \
- test_klp_callbacks_demo.o \
- test_klp_callbacks_demo2.o \
- test_klp_callbacks_busy.o \
- test_klp_callbacks_mod.o \
- test_klp_livepatch.o \
- test_klp_shadow_vars.o \
- test_klp_state.o \
- test_klp_state2.o \
- test_klp_state3.o
diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
index 02fadc9d55e0..119e2bbebe5d 100644
--- a/tools/testing/selftests/livepatch/Makefile
+++ b/tools/testing/selftests/livepatch/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0

+TEST_GEN_MODS_DIR := test_modules
TEST_PROGS_EXTENDED := functions.sh
TEST_PROGS := \
test-livepatch.sh \
diff --git a/tools/testing/selftests/livepatch/README b/tools/testing/selftests/livepatch/README
index 0942dd5826f8..c5eb3cb67b66 100644
--- a/tools/testing/selftests/livepatch/README
+++ b/tools/testing/selftests/livepatch/README
@@ -13,23 +13,26 @@ the message buffer for only the duration of each individual test.)
Config
------

-Set these config options and their prerequisites:
-
-CONFIG_LIVEPATCH=y
-CONFIG_TEST_LIVEPATCH=m
+Set CONFIG_LIVEPATCH=y option and it's prerequisites.


Running the tests
-----------------

-Test kernel modules are built as part of lib/ (make modules) and need to
-be installed (make modules_install) as the test scripts will modprobe
-them.
+Test kernel modules are built before running the livepatch selftests. The
+modules are located under test_modules directory, and are built as out-of-tree
+modules. This is specially useful since the same sources can be built and
+tested on systems with different kABI, ensuring they the tests are backwards
+compatible. The modules will be loaded by the test scripts using insmod.

To run the livepatch selftests, from the top of the kernel source tree:

% make -C tools/testing/selftests TARGETS=livepatch run_tests

+or
+
+ % make kselftest TARGETS=livepatch
+

Adding tests
------------
diff --git a/tools/testing/selftests/livepatch/config b/tools/testing/selftests/livepatch/config
index ad23100cb27c..e88bf518a23a 100644
--- a/tools/testing/selftests/livepatch/config
+++ b/tools/testing/selftests/livepatch/config
@@ -1,3 +1,2 @@
CONFIG_LIVEPATCH=y
CONFIG_DYNAMIC_DEBUG=y
-CONFIG_TEST_LIVEPATCH=m
diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
index c8416c54b463..e60cf09491a6 100644
--- a/tools/testing/selftests/livepatch/functions.sh
+++ b/tools/testing/selftests/livepatch/functions.sh
@@ -127,16 +127,14 @@ function loop_until() {
done
}

-function assert_mod() {
- local mod="$1"
-
- modprobe --dry-run "$mod" &>/dev/null
-}
-
function is_livepatch_mod() {
local mod="$1"

- if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then
+ if [[ ! -f "test_modules/$mod.ko" ]]; then
+ die "Can't find \"test_modules/$mod.ko\", try \"make\""
+ fi
+
+ if [[ $(modinfo "test_modules/$mod.ko" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then
return 0
fi

@@ -146,9 +144,9 @@ function is_livepatch_mod() {
function __load_mod() {
local mod="$1"; shift

- local msg="% modprobe $mod $*"
+ local msg="% insmod test_modules/$mod.ko $*"
log "${msg%% }"
- ret=$(modprobe "$mod" "$@" 2>&1)
+ ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
if [[ "$ret" != "" ]]; then
die "$ret"
fi
@@ -161,13 +159,10 @@ function __load_mod() {

# load_mod(modname, params) - load a kernel module
# modname - module name to load
-# params - module parameters to pass to modprobe
+# params - module parameters to pass to insmod
function load_mod() {
local mod="$1"; shift

- assert_mod "$mod" ||
- skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
-
is_livepatch_mod "$mod" &&
die "use load_lp() to load the livepatch module $mod"

@@ -177,13 +172,10 @@ function load_mod() {
# load_lp_nowait(modname, params) - load a kernel module with a livepatch
# but do not wait on until the transition finishes
# modname - module name to load
-# params - module parameters to pass to modprobe
+# params - module parameters to pass to insmod
function load_lp_nowait() {
local mod="$1"; shift

- assert_mod "$mod" ||
- skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
-
is_livepatch_mod "$mod" ||
die "module $mod is not a livepatch"

@@ -196,7 +188,7 @@ function load_lp_nowait() {

# load_lp(modname, params) - load a kernel module with a livepatch
# modname - module name to load
-# params - module parameters to pass to modprobe
+# params - module parameters to pass to insmod
function load_lp() {
local mod="$1"; shift

@@ -209,13 +201,13 @@ function load_lp() {

# load_failing_mod(modname, params) - load a kernel module, expect to fail
# modname - module name to load
-# params - module parameters to pass to modprobe
+# params - module parameters to pass to insmod
function load_failing_mod() {
local mod="$1"; shift

- local msg="% modprobe $mod $*"
+ local msg="% insmod test_modules/$mod.ko $*"
log "${msg%% }"
- ret=$(modprobe "$mod" "$@" 2>&1)
+ ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
if [[ "$ret" == "" ]]; then
die "$mod unexpectedly loaded"
fi
diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh
index 90b26dbb2626..32b150e25b10 100755
--- a/tools/testing/selftests/livepatch/test-callbacks.sh
+++ b/tools/testing/selftests/livepatch/test-callbacks.sh
@@ -34,9 +34,9 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
unload_mod $MOD_TARGET

-check_result "% modprobe $MOD_TARGET
+check_result "% insmod test_modules/$MOD_TARGET.ko
$MOD_TARGET: ${MOD_TARGET}_init
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -81,7 +81,7 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
unload_mod $MOD_TARGET

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -89,7 +89,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_TARGET
+% insmod test_modules/$MOD_TARGET.ko
livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
@@ -129,9 +129,9 @@ unload_mod $MOD_TARGET
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_TARGET
+check_result "% insmod test_modules/$MOD_TARGET.ko
$MOD_TARGET: ${MOD_TARGET}_init
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -177,7 +177,7 @@ unload_mod $MOD_TARGET
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -185,7 +185,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_TARGET
+% insmod test_modules/$MOD_TARGET.ko
livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
@@ -219,7 +219,7 @@ load_lp $MOD_LIVEPATCH
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -254,9 +254,9 @@ load_mod $MOD_TARGET
load_failing_mod $MOD_LIVEPATCH pre_patch_ret=-19
unload_mod $MOD_TARGET

-check_result "% modprobe $MOD_TARGET
+check_result "% insmod test_modules/$MOD_TARGET.ko
$MOD_TARGET: ${MOD_TARGET}_init
-% modprobe $MOD_LIVEPATCH pre_patch_ret=-19
+% insmod test_modules/$MOD_LIVEPATCH.ko pre_patch_ret=-19
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
test_klp_callbacks_demo: pre_patch_callback: vmlinux
@@ -265,7 +265,7 @@ livepatch: failed to enable patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': canceling patching transition, going to unpatch
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
livepatch: '$MOD_LIVEPATCH': unpatching complete
-modprobe: ERROR: could not insert '$MOD_LIVEPATCH': No such device
+insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: No such device
% rmmod $MOD_TARGET
$MOD_TARGET: ${MOD_TARGET}_exit"

@@ -295,7 +295,7 @@ load_failing_mod $MOD_TARGET
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -304,12 +304,12 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
livepatch: '$MOD_LIVEPATCH': patching complete
% echo -19 > /sys/module/$MOD_LIVEPATCH/parameters/pre_patch_ret
-% modprobe $MOD_TARGET
+% insmod test_modules/$MOD_TARGET.ko
livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
livepatch: pre-patch callback failed for object '$MOD_TARGET'
livepatch: patch '$MOD_LIVEPATCH' failed for module '$MOD_TARGET', refusing to load module '$MOD_TARGET'
-modprobe: ERROR: could not insert '$MOD_TARGET': No such device
+insmod: ERROR: could not insert module test_modules/$MOD_TARGET.ko: No such device
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux
@@ -340,11 +340,11 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
unload_mod $MOD_TARGET_BUSY

-check_result "% modprobe $MOD_TARGET_BUSY block_transition=N
+check_result "% insmod test_modules/$MOD_TARGET_BUSY.ko block_transition=N
$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init
$MOD_TARGET_BUSY: busymod_work_func enter
$MOD_TARGET_BUSY: busymod_work_func exit
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -354,7 +354,7 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_TARGET
+% insmod test_modules/$MOD_TARGET.ko
livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
@@ -421,16 +421,16 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
unload_mod $MOD_TARGET_BUSY

-check_result "% modprobe $MOD_TARGET_BUSY block_transition=Y
+check_result "% insmod test_modules/$MOD_TARGET_BUSY.ko block_transition=Y
$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init
$MOD_TARGET_BUSY: busymod_work_func enter
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state
livepatch: '$MOD_LIVEPATCH': starting patching transition
-% modprobe $MOD_TARGET
+% insmod test_modules/$MOD_TARGET.ko
livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
$MOD_TARGET: ${MOD_TARGET}_init
@@ -467,7 +467,7 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -475,7 +475,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_LIVEPATCH2
+% insmod test_modules/$MOD_LIVEPATCH2.ko
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
@@ -523,7 +523,7 @@ disable_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -531,7 +531,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_LIVEPATCH2 replace=1
+% insmod test_modules/$MOD_LIVEPATCH2.ko replace=1
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh
index 825540a5194d..730218bce99c 100755
--- a/tools/testing/selftests/livepatch/test-ftrace.sh
+++ b/tools/testing/selftests/livepatch/test-ftrace.sh
@@ -35,7 +35,7 @@ disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

check_result "livepatch: kernel.ftrace_enabled = 0
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: failed to register ftrace handler for function 'cmdline_proc_show' (-16)
@@ -44,9 +44,9 @@ livepatch: failed to enable patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': canceling patching transition, going to unpatch
livepatch: '$MOD_LIVEPATCH': completing unpatching transition
livepatch: '$MOD_LIVEPATCH': unpatching complete
-modprobe: ERROR: could not insert '$MOD_LIVEPATCH': Device or resource busy
+insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: Device or resource busy
livepatch: kernel.ftrace_enabled = 1
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: '$MOD_LIVEPATCH': starting patching transition
diff --git a/tools/testing/selftests/livepatch/test-livepatch.sh b/tools/testing/selftests/livepatch/test-livepatch.sh
index 5fe79ac34be1..e3455a6b1158 100755
--- a/tools/testing/selftests/livepatch/test-livepatch.sh
+++ b/tools/testing/selftests/livepatch/test-livepatch.sh
@@ -31,7 +31,7 @@ if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH: this has been live patched" ]]
die "livepatch kselftest(s) failed"
fi

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: '$MOD_LIVEPATCH': starting patching transition
@@ -75,14 +75,14 @@ unload_lp $MOD_LIVEPATCH
grep 'live patched' /proc/cmdline > /dev/kmsg
grep 'live patched' /proc/meminfo > /dev/kmsg

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
livepatch: '$MOD_LIVEPATCH': patching complete
$MOD_LIVEPATCH: this has been live patched
-% modprobe $MOD_REPLACE replace=0
+% insmod test_modules/$MOD_REPLACE.ko replace=0
livepatch: enabling patch '$MOD_REPLACE'
livepatch: '$MOD_REPLACE': initializing patching transition
livepatch: '$MOD_REPLACE': starting patching transition
@@ -135,14 +135,14 @@ unload_lp $MOD_REPLACE
grep 'live patched' /proc/cmdline > /dev/kmsg
grep 'live patched' /proc/meminfo > /dev/kmsg

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: '$MOD_LIVEPATCH': starting patching transition
livepatch: '$MOD_LIVEPATCH': completing patching transition
livepatch: '$MOD_LIVEPATCH': patching complete
$MOD_LIVEPATCH: this has been live patched
-% modprobe $MOD_REPLACE replace=1
+% insmod test_modules/$MOD_REPLACE.ko replace=1
livepatch: enabling patch '$MOD_REPLACE'
livepatch: '$MOD_REPLACE': initializing patching transition
livepatch: '$MOD_REPLACE': starting patching transition
diff --git a/tools/testing/selftests/livepatch/test-shadow-vars.sh b/tools/testing/selftests/livepatch/test-shadow-vars.sh
index e04cb354f56b..1218c155bffe 100755
--- a/tools/testing/selftests/livepatch/test-shadow-vars.sh
+++ b/tools/testing/selftests/livepatch/test-shadow-vars.sh
@@ -16,7 +16,7 @@ start_test "basic shadow variable API"
load_mod $MOD_TEST
unload_mod $MOD_TEST

-check_result "% modprobe $MOD_TEST
+check_result "% insmod test_modules/$MOD_TEST.ko
$MOD_TEST: klp_shadow_get(obj=PTR1, id=0x1234) = PTR0
$MOD_TEST: got expected NULL result
$MOD_TEST: shadow_ctor: PTR3 -> PTR2
diff --git a/tools/testing/selftests/livepatch/test-state.sh b/tools/testing/selftests/livepatch/test-state.sh
index 38656721c958..10a52ac06185 100755
--- a/tools/testing/selftests/livepatch/test-state.sh
+++ b/tools/testing/selftests/livepatch/test-state.sh
@@ -19,7 +19,7 @@ load_lp $MOD_LIVEPATCH
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -51,7 +51,7 @@ unload_lp $MOD_LIVEPATCH
disable_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH2

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
$MOD_LIVEPATCH: pre_patch_callback: vmlinux
@@ -61,7 +61,7 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
$MOD_LIVEPATCH: post_patch_callback: vmlinux
$MOD_LIVEPATCH: fix_console_loglevel: fixing console_loglevel
livepatch: '$MOD_LIVEPATCH': patching complete
-% modprobe $MOD_LIVEPATCH2
+% insmod test_modules/$MOD_LIVEPATCH2.ko
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
@@ -96,7 +96,7 @@ disable_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH3

-check_result "% modprobe $MOD_LIVEPATCH2
+check_result "% insmod test_modules/$MOD_LIVEPATCH2.ko
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
@@ -106,7 +106,7 @@ livepatch: '$MOD_LIVEPATCH2': completing patching transition
$MOD_LIVEPATCH2: post_patch_callback: vmlinux
$MOD_LIVEPATCH2: fix_console_loglevel: fixing console_loglevel
livepatch: '$MOD_LIVEPATCH2': patching complete
-% modprobe $MOD_LIVEPATCH3
+% insmod test_modules/$MOD_LIVEPATCH3.ko
livepatch: enabling patch '$MOD_LIVEPATCH3'
livepatch: '$MOD_LIVEPATCH3': initializing patching transition
$MOD_LIVEPATCH3: pre_patch_callback: vmlinux
@@ -117,7 +117,7 @@ $MOD_LIVEPATCH3: post_patch_callback: vmlinux
$MOD_LIVEPATCH3: fix_console_loglevel: taking over the console_loglevel change
livepatch: '$MOD_LIVEPATCH3': patching complete
% rmmod $MOD_LIVEPATCH2
-% modprobe $MOD_LIVEPATCH2
+% insmod test_modules/$MOD_LIVEPATCH2.ko
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
@@ -149,7 +149,7 @@ load_failing_mod $MOD_LIVEPATCH
disable_lp $MOD_LIVEPATCH2
unload_lp $MOD_LIVEPATCH2

-check_result "% modprobe $MOD_LIVEPATCH2
+check_result "% insmod test_modules/$MOD_LIVEPATCH2.ko
livepatch: enabling patch '$MOD_LIVEPATCH2'
livepatch: '$MOD_LIVEPATCH2': initializing patching transition
$MOD_LIVEPATCH2: pre_patch_callback: vmlinux
@@ -159,9 +159,9 @@ livepatch: '$MOD_LIVEPATCH2': completing patching transition
$MOD_LIVEPATCH2: post_patch_callback: vmlinux
$MOD_LIVEPATCH2: fix_console_loglevel: fixing console_loglevel
livepatch: '$MOD_LIVEPATCH2': patching complete
-% modprobe $MOD_LIVEPATCH
+% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: Livepatch patch ($MOD_LIVEPATCH) is not compatible with the already installed livepatches.
-modprobe: ERROR: could not insert '$MOD_LIVEPATCH': Invalid argument
+insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: Invalid parameters
% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH2/enabled
livepatch: '$MOD_LIVEPATCH2': initializing unpatching transition
$MOD_LIVEPATCH2: pre_unpatch_callback: vmlinux
diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
index 7f76f280189a..6c646afa7395 100755
--- a/tools/testing/selftests/livepatch/test-sysfs.sh
+++ b/tools/testing/selftests/livepatch/test-sysfs.sh
@@ -27,7 +27,7 @@ disable_lp $MOD_LIVEPATCH

unload_lp $MOD_LIVEPATCH

-check_result "% modprobe $MOD_LIVEPATCH
+check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
livepatch: enabling patch '$MOD_LIVEPATCH'
livepatch: '$MOD_LIVEPATCH': initializing patching transition
livepatch: '$MOD_LIVEPATCH': starting patching transition
@@ -56,7 +56,7 @@ check_sysfs_value "$MOD_LIVEPATCH" "$MOD_TARGET/patched" "0"
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH

-check_result "% modprobe test_klp_callbacks_demo
+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
@@ -64,7 +64,7 @@ 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
-% modprobe test_klp_callbacks_mod
+% 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
diff --git a/tools/testing/selftests/livepatch/test_modules/Makefile b/tools/testing/selftests/livepatch/test_modules/Makefile
new file mode 100644
index 000000000000..6f7c2103d27d
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test_modules/Makefile
@@ -0,0 +1,19 @@
+TESTMODS_DIR := $(realpath $(dir $(abspath $(lastword $(MAKEFILE_LIST)))))
+KDIR ?= /lib/modules/$(shell uname -r)/build
+
+obj-m += test_klp_atomic_replace.o \
+ test_klp_callbacks_busy.o \
+ test_klp_callbacks_demo.o \
+ test_klp_callbacks_demo2.o \
+ test_klp_callbacks_mod.o \
+ test_klp_livepatch.o \
+ test_klp_state.o \
+ test_klp_state2.o \
+ test_klp_state3.o \
+ test_klp_shadow_vars.o
+
+modules:
+ $(Q)$(MAKE) -C $(KDIR) modules KBUILD_EXTMOD=$(TESTMODS_DIR)
+
+clean:
+ $(Q)$(MAKE) -C $(KDIR) clean KBUILD_EXTMOD=$(TESTMODS_DIR)
diff --git a/lib/livepatch/test_klp_atomic_replace.c b/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
similarity index 100%
rename from lib/livepatch/test_klp_atomic_replace.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
diff --git a/lib/livepatch/test_klp_callbacks_busy.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_busy.c
similarity index 100%
rename from lib/livepatch/test_klp_callbacks_busy.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_busy.c
diff --git a/lib/livepatch/test_klp_callbacks_demo.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
similarity index 100%
rename from lib/livepatch/test_klp_callbacks_demo.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
diff --git a/lib/livepatch/test_klp_callbacks_demo2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
similarity index 100%
rename from lib/livepatch/test_klp_callbacks_demo2.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
diff --git a/lib/livepatch/test_klp_callbacks_mod.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_mod.c
similarity index 100%
rename from lib/livepatch/test_klp_callbacks_mod.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_mod.c
diff --git a/lib/livepatch/test_klp_livepatch.c b/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
similarity index 100%
rename from lib/livepatch/test_klp_livepatch.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
diff --git a/lib/livepatch/test_klp_shadow_vars.c b/tools/testing/selftests/livepatch/test_modules/test_klp_shadow_vars.c
similarity index 100%
rename from lib/livepatch/test_klp_shadow_vars.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_shadow_vars.c
diff --git a/lib/livepatch/test_klp_state.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
similarity index 100%
rename from lib/livepatch/test_klp_state.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_state.c
diff --git a/lib/livepatch/test_klp_state2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
similarity index 100%
rename from lib/livepatch/test_klp_state2.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
diff --git a/lib/livepatch/test_klp_state3.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state3.c
similarity index 100%
rename from lib/livepatch/test_klp_state3.c
rename to tools/testing/selftests/livepatch/test_modules/test_klp_state3.c

--
2.42.0

2023-10-31 21:12:48

by Marcos Paulo de Souza

Subject: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

The test proves that a syscall can be livepatched. It is interesting
because syscalls are called a tricky way. Also the process gets
livepatched either when sleeping in the userspace or when entering
or leaving the kernel space.

The livepatch is a bit tricky:
1. The syscall function name is architecture specific. Also
ARCH_HAS_SYSCALL_WRAPPER must be taken in account.

2. The syscall must stay working the same way for other processes
on the system. It is solved by decrementing a counter only
for PIDs of the test processes. It means that the test processes
has to call the livepatched syscall at least once.

The test creates one userspace process per online cpu. The processes
are calling getpid in a busy loop. The intention is to create random
locations when the livepatch gets enabled. Nothing is guarantted.
The magic is in the randomness.

Signed-off-by: Marcos Paulo de Souza <[email protected]>
---
tools/testing/selftests/livepatch/Makefile | 4 +-
tools/testing/selftests/livepatch/test-syscall.sh | 53 ++++++++++
.../selftests/livepatch/test_klp-call_getpid.c | 44 ++++++++
.../selftests/livepatch/test_modules/Makefile | 3 +-
.../livepatch/test_modules/test_klp_syscall.c | 116 +++++++++++++++++++++
5 files changed, 218 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
index 119e2bbebe5d..35418a4790be 100644
--- a/tools/testing/selftests/livepatch/Makefile
+++ b/tools/testing/selftests/livepatch/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0

+TEST_GEN_FILES := test_klp-call_getpid
TEST_GEN_MODS_DIR := test_modules
TEST_PROGS_EXTENDED := functions.sh
TEST_PROGS := \
@@ -8,7 +9,8 @@ TEST_PROGS := \
test-shadow-vars.sh \
test-state.sh \
test-ftrace.sh \
- test-sysfs.sh
+ test-sysfs.sh \
+ test-syscall.sh

TEST_FILES := settings

diff --git a/tools/testing/selftests/livepatch/test-syscall.sh b/tools/testing/selftests/livepatch/test-syscall.sh
new file mode 100755
index 000000000000..b76a881d4013
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test-syscall.sh
@@ -0,0 +1,53 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2023 SUSE
+# Author: Marcos Paulo de Souza <[email protected]>
+
+. $(dirname $0)/functions.sh
+
+MOD_SYSCALL=test_klp_syscall
+
+setup_config
+
+# - Start _NRPROC processes calling getpid and load a livepatch to patch the
+# getpid syscall. Check if all the processes transitioned to the livepatched
+# state.
+
+start_test "patch getpid syscall while being heavily hammered"
+
+for i in $(seq 1 $(getconf _NPROCESSORS_ONLN)); do
+ ./test_klp-call_getpid &
+ pids[$i]="$!"
+done
+
+pid_list=$(echo ${pids[@]} | tr ' ' ',')
+load_lp $MOD_SYSCALL klp_pids=$pid_list
+
+# wait for all tasks to transition to patched state
+loop_until 'grep -q '^0$' /sys/kernel/test_klp_syscall/npids'
+
+pending_pids=$(cat /sys/kernel/test_klp_syscall/npids)
+log "$MOD_SYSCALL: Remaining not livepatched processes: $pending_pids"
+
+for pid in ${pids[@]}; do
+ kill $pid || true
+done
+
+disable_lp $MOD_SYSCALL
+unload_lp $MOD_SYSCALL
+
+check_result "% insmod test_modules/$MOD_SYSCALL.ko klp_pids=$pid_list
+livepatch: enabling patch '$MOD_SYSCALL'
+livepatch: '$MOD_SYSCALL': initializing patching transition
+livepatch: '$MOD_SYSCALL': starting patching transition
+livepatch: '$MOD_SYSCALL': completing patching transition
+livepatch: '$MOD_SYSCALL': patching complete
+$MOD_SYSCALL: Remaining not livepatched processes: 0
+% echo 0 > /sys/kernel/livepatch/$MOD_SYSCALL/enabled
+livepatch: '$MOD_SYSCALL': initializing unpatching transition
+livepatch: '$MOD_SYSCALL': starting unpatching transition
+livepatch: '$MOD_SYSCALL': completing unpatching transition
+livepatch: '$MOD_SYSCALL': unpatching complete
+% rmmod $MOD_SYSCALL"
+
+exit 0
diff --git a/tools/testing/selftests/livepatch/test_klp-call_getpid.c b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
new file mode 100644
index 000000000000..ce321a2d7308
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023 SUSE
+ * Authors: Libor Pechacek <[email protected]>
+ * Marcos Paulo de Souza <[email protected]>
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <signal.h>
+
+static int stop;
+static int sig_int;
+
+void hup_handler(int signum)
+{
+ stop = 1;
+}
+
+void int_handler(int signum)
+{
+ stop = 1;
+ sig_int = 1;
+}
+
+int main(int argc, char *argv[])
+{
+ long count = 0;
+
+ signal(SIGHUP, &hup_handler);
+ signal(SIGINT, &int_handler);
+
+ while (!stop) {
+ (void)syscall(SYS_getpid);
+ count++;
+ }
+
+ if (sig_int)
+ printf("%ld iterations done\n", count);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/livepatch/test_modules/Makefile b/tools/testing/selftests/livepatch/test_modules/Makefile
index 6f7c2103d27d..f5e880269bff 100644
--- a/tools/testing/selftests/livepatch/test_modules/Makefile
+++ b/tools/testing/selftests/livepatch/test_modules/Makefile
@@ -10,7 +10,8 @@ obj-m += test_klp_atomic_replace.o \
test_klp_state.o \
test_klp_state2.o \
test_klp_state3.o \
- test_klp_shadow_vars.o
+ test_klp_shadow_vars.o \
+ test_klp_syscall.o

modules:
$(Q)$(MAKE) -C $(KDIR) modules KBUILD_EXTMOD=$(TESTMODS_DIR)
diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
new file mode 100644
index 000000000000..619496cc3481
--- /dev/null
+++ b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017-2023 SUSE
+ * Authors: Libor Pechacek <[email protected]>
+ * Nicolai Stange <[email protected]>
+ * Marcos Paulo de Souza <[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#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_
+#else
+/* powerpc does not select ARCH_HAS_SYSCALL_WRAPPER */
+#define FN_PREFIX
+#endif
+
+/* Protects klp_pids */
+static DEFINE_MUTEX(kpid_mutex);
+
+static unsigned int npids, npids_pending;
+static int klp_pids[NR_CPUS];
+module_param_array(klp_pids, int, &npids_pending, 0);
+MODULE_PARM_DESC(klp_pids, "Array of pids to be transitioned to livepatched state.");
+
+static ssize_t npids_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", npids_pending);
+}
+
+static struct kobj_attribute klp_attr = __ATTR_RO(npids);
+static struct kobject *klp_kobj;
+
+asmlinkage long lp_sys_getpid(void)
+{
+ int i;
+
+ mutex_lock(&kpid_mutex);
+ if (npids_pending > 0) {
+ for (i = 0; i < npids; i++) {
+ if (current->pid == klp_pids[i]) {
+ klp_pids[i] = 0;
+ npids_pending--;
+ break;
+ }
+ }
+ }
+ mutex_unlock(&kpid_mutex);
+
+ return task_tgid_vnr(current);
+}
+
+static struct klp_func vmlinux_funcs[] = {
+ {
+ .old_name = __stringify(FN_PREFIX) "sys_getpid",
+ .new_func = lp_sys_getpid,
+ }, {}
+};
+
+static struct klp_object objs[] = {
+ {
+ /* name being NULL means vmlinux */
+ .funcs = vmlinux_funcs,
+ }, {}
+};
+
+static struct klp_patch patch = {
+ .mod = THIS_MODULE,
+ .objs = objs,
+};
+
+static int livepatch_init(void)
+{
+ int ret;
+
+ klp_kobj = kobject_create_and_add("test_klp_syscall", kernel_kobj);
+ if (!klp_kobj)
+ return -ENOMEM;
+
+ ret = sysfs_create_file(klp_kobj, &klp_attr.attr);
+ if (ret) {
+ kobject_put(klp_kobj);
+ return ret;
+ }
+
+ /*
+ * Save the number pids to transition to livepatched state before the
+ * number of pending pids is decremented.
+ */
+ npids = npids_pending;
+
+ return klp_enable_patch(&patch);
+}
+
+static void livepatch_exit(void)
+{
+ kobject_put(klp_kobj);
+}
+
+module_init(livepatch_init);
+module_exit(livepatch_exit);
+MODULE_LICENSE("GPL");
+MODULE_INFO(livepatch, "Y");
+MODULE_AUTHOR("Libor Pechacek <[email protected]>");
+MODULE_AUTHOR("Nicolai Stange <[email protected]>");
+MODULE_AUTHOR("Marcos Paulo de Souza <[email protected]>");
+MODULE_DESCRIPTION("Livepatch test: syscall transition");

--
2.42.0

2023-10-31 21:12:48

by Marcos Paulo de Souza

Subject: [PATCH v3 1/3] kselftests: lib.mk: Add TEST_GEN_MODS_DIR variable

Add TEST_GEN_MODS_DIR variable for kselftests. It can point to
a directory containing kernel modules that will be used by
selftest scripts.

The modules are built as external modules for the running kernel.
As a result they are always binary compatible and the same tests
can be used for older or newer kernels.

The build requires "kernel-devel" package to be installed.
For example, in the upstream sources, the rpm devel package
is produced by "make rpm-pkg"

The modules can be built independently by

make -C tools/testing/selftests/livepatch/

or they will be automatically built before running the tests via

make -C tools/testing/selftests/livepatch/ run_tests

Note that they are _not_ built when running the standalone
tests by calling, for example, ./test-state.sh.

Signed-off-by: Marcos Paulo de Souza <[email protected]>
---
Documentation/dev-tools/kselftest.rst | 4 ++++
tools/testing/selftests/lib.mk | 20 +++++++++++++++-----
2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst
index deede972f254..736c671c47b6 100644
--- a/Documentation/dev-tools/kselftest.rst
+++ b/Documentation/dev-tools/kselftest.rst
@@ -245,6 +245,10 @@ Contributing new tests (details)
TEST_PROGS, TEST_GEN_PROGS mean it is the executable tested by
default.

+ TEST_GEN_MODS_DIR should be used by tests that require modules to be built
+ before the test starts. The variable will contain the name of the directory
+ containing the modules.
+
TEST_CUSTOM_PROGS should be used by tests that require custom build
rules and prevent common build rule use.

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index 118e0964bda9..6c7c5a0112cf 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -70,12 +70,15 @@ KHDR_INCLUDES := -isystem $(KHDR_DIR)
# TEST_PROGS are for test shell scripts.
# TEST_CUSTOM_PROGS and TEST_PROGS will be run by common run_tests
# and install targets. Common clean doesn't touch them.
+# TEST_GEN_MODS_DIR is used to specify a directory with modules to be built
+# before the test executes. These modules are cleaned on the clean target as well.
TEST_GEN_PROGS := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS))
TEST_GEN_PROGS_EXTENDED := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS_EXTENDED))
TEST_GEN_FILES := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_FILES))
+TEST_GEN_MODS_DIR := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_MODS_DIR))

all: kernel_header_files $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) \
- $(TEST_GEN_FILES)
+ $(TEST_GEN_FILES) $(if $(TEST_GEN_MODS_DIR),gen_mods_dir)

kernel_header_files:
@ls $(KHDR_DIR)/linux/*.h >/dev/null 2>/dev/null; \
@@ -105,8 +108,8 @@ endef

run_tests: all
ifdef building_out_of_srctree
- @if [ "X$(TEST_PROGS)$(TEST_PROGS_EXTENDED)$(TEST_FILES)" != "X" ]; then \
- rsync -aq --copy-unsafe-links $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(OUTPUT); \
+ @if [ "X$(TEST_PROGS)$(TEST_PROGS_EXTENDED)$(TEST_FILES)$(TEST_GEN_MODS_DIR)" != "X" ]; then \
+ rsync -aq --copy-unsafe-links $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(TEST_GEN_MODS_DIR) $(OUTPUT); \
fi
@if [ "X$(TEST_PROGS)" != "X" ]; then \
$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) \
@@ -118,6 +121,12 @@ else
@$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_PROGS))
endif

+gen_mods_dir:
+ $(Q)$(MAKE) -C $(TEST_GEN_MODS_DIR)
+
+clean_mods_dir:
+ $(Q)$(MAKE) -C $(TEST_GEN_MODS_DIR) clean
+
define INSTALL_SINGLE_RULE
$(if $(INSTALL_LIST),@mkdir -p $(INSTALL_PATH))
$(if $(INSTALL_LIST),rsync -a --copy-unsafe-links $(INSTALL_LIST) $(INSTALL_PATH)/)
@@ -131,6 +140,7 @@ define INSTALL_RULE
$(eval INSTALL_LIST = $(TEST_CUSTOM_PROGS)) $(INSTALL_SINGLE_RULE)
$(eval INSTALL_LIST = $(TEST_GEN_PROGS_EXTENDED)) $(INSTALL_SINGLE_RULE)
$(eval INSTALL_LIST = $(TEST_GEN_FILES)) $(INSTALL_SINGLE_RULE)
+ $(eval INSTALL_LIST = $(TEST_GEN_MODS_DIR)) $(INSTALL_SINGLE_RULE)
$(eval INSTALL_LIST = $(wildcard config settings)) $(INSTALL_SINGLE_RULE)
endef

@@ -156,7 +166,7 @@ define CLEAN
$(RM) -r $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(EXTRA_CLEAN)
endef

-clean:
+clean: $(if $(TEST_GEN_MODS_DIR),clean_mods_dir)
$(CLEAN)

# Enables to extend CFLAGS and LDFLAGS from command line, e.g.
@@ -187,4 +197,4 @@ $(OUTPUT)/%:%.S
$(LINK.S) $^ $(LDLIBS) -o $@
endif

-.PHONY: run_tests all clean install emit_tests
+.PHONY: run_tests all clean install emit_tests gen_mods_dir clean_mods_dir

--
2.42.0

2023-11-30 13:42:34

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 0/3] livepatch: Move modules to selftests and add a new test

Humble ping :)

On Tue, Oct 31, 2023 at 06:10:50PM -0300, Marcos Paulo de Souza wrote:
> This patchset moves the current kernel testing livepatch modules from
> lib/livepatches to tools/testing/selftest/livepatch/test_modules, and compiles
> them as out-of-tree modules before testing.
>
> There is also a new test being added. This new test exercises multiple processes
> calling a syscall, while a livepatch patched the syscall.
>
> Why this move is an improvement:
> * The modules are now compiled as out-of-tree modules against the current
> running kernel, making them capable of being tested on different systems with
> newer or older kernels.
> * Such approach now needs kernel-devel package to be installed, since they are
> out-of-tree modules. These can be generated by running "make rpm-pkg" in the
> kernel source.
>
> What needs to be solved:
> * Currently gen_tar only packages the resulting binaries of the tests, and not
> the sources. For the current approach, the newly added modules would be
> compiled and then packaged. It works when testing on a system with the same
> kernel version. But it will fail when running on a machine with different kernel
> version, since module was compiled against the kernel currently running.
>
> This is not a new problem, just aligning the expectations. For the current
> approach to be truly system agnostic gen_tar would need to include the module
> and program sources to be compiled in the target systems.
>
> I'm sending the patches now so it can be discussed before Plumbers.
>
> Thanks in advance!
> Marcos
>
> To: Shuah Khan <[email protected]>
> To: Jonathan Corbet <[email protected]>
> To: Heiko Carstens <[email protected]>
> To: Vasily Gorbik <[email protected]>
> To: Alexander Gordeev <[email protected]>
> To: Christian Borntraeger <[email protected]>
> To: Sven Schnelle <[email protected]>
> To: Josh Poimboeuf <[email protected]>
> To: Jiri Kosina <[email protected]>
> To: Miroslav Benes <[email protected]>
> To: Petr Mladek <[email protected]>
> To: Joe Lawrence <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Marcos Paulo de Souza <[email protected]>
>
> Changes in v3:
> * Rebased on top of v6.6-rc5
> * The commits messages were improved (Thanks Petr!)
> * Created TEST_GEN_MODS_DIR variable to point to a directly that contains kernel
> modules, and adapt selftests to build it before running the test.
> * Moved test_klp-call_getpid out of test_programs, since the gen_tar
> would just copy the generated test programs to the livepatches dir,
> and so scripts relying on test_programs/test_klp-call_getpid will fail.
> * Added a module_param for klp_pids, describing it's usage.
> * Simplified the call_getpid program to ignore the return of getpid syscall,
> since we only want to make sure the process transitions correctly to the
> patched stated
> * The test-syscall.sh not prints a log message showing the number of remaining
> processes to transition into to livepatched state, and check_output expects it
> to be 0.
> * Added MODULE_AUTHOR and MODULE_DESCRIPTION to test_klp_syscall.c
>
> The v2 can be seen here:
> https://lore.kernel.org/linux-kselftest/[email protected]/
>
> ---
> Marcos Paulo de Souza (3):
> kselftests: lib.mk: Add TEST_GEN_MODS_DIR variable
> livepatch: Move tests from lib/livepatch to selftests/livepatch
> selftests: livepatch: Test livepatching a heavily called syscall
>
> Documentation/dev-tools/kselftest.rst | 4 +
> arch/s390/configs/debug_defconfig | 1 -
> arch/s390/configs/defconfig | 1 -
> lib/Kconfig.debug | 22 ----
> lib/Makefile | 2 -
> lib/livepatch/Makefile | 14 ---
> tools/testing/selftests/lib.mk | 20 +++-
> tools/testing/selftests/livepatch/Makefile | 5 +-
> tools/testing/selftests/livepatch/README | 17 +--
> tools/testing/selftests/livepatch/config | 1 -
> tools/testing/selftests/livepatch/functions.sh | 34 +++---
> .../testing/selftests/livepatch/test-callbacks.sh | 50 ++++-----
> tools/testing/selftests/livepatch/test-ftrace.sh | 6 +-
> .../testing/selftests/livepatch/test-livepatch.sh | 10 +-
> .../selftests/livepatch/test-shadow-vars.sh | 2 +-
> tools/testing/selftests/livepatch/test-state.sh | 18 ++--
> tools/testing/selftests/livepatch/test-syscall.sh | 53 ++++++++++
> tools/testing/selftests/livepatch/test-sysfs.sh | 6 +-
> .../selftests/livepatch/test_klp-call_getpid.c | 44 ++++++++
> .../selftests/livepatch/test_modules/Makefile | 20 ++++
> .../test_modules}/test_klp_atomic_replace.c | 0
> .../test_modules}/test_klp_callbacks_busy.c | 0
> .../test_modules}/test_klp_callbacks_demo.c | 0
> .../test_modules}/test_klp_callbacks_demo2.c | 0
> .../test_modules}/test_klp_callbacks_mod.c | 0
> .../livepatch/test_modules}/test_klp_livepatch.c | 0
> .../livepatch/test_modules}/test_klp_shadow_vars.c | 0
> .../livepatch/test_modules}/test_klp_state.c | 0
> .../livepatch/test_modules}/test_klp_state2.c | 0
> .../livepatch/test_modules}/test_klp_state3.c | 0
> .../livepatch/test_modules/test_klp_syscall.c | 116 +++++++++++++++++++++
> 31 files changed, 325 insertions(+), 121 deletions(-)
> ---
> base-commit: 6489bf2e1df1c84e9bcd4694029ff35b39fd3397
> change-id: 20231031-send-lp-kselftests-4c917dcd4565
>
> Best regards,
> --
> Marcos Paulo de Souza <[email protected]>
>

2023-11-30 23:24:56

by Shuah Khan

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 10/31/23 15:10, Marcos Paulo de Souza wrote:
> The test proves that a syscall can be livepatched. It is interesting
> because syscalls are called a tricky way. Also the process gets
> livepatched either when sleeping in the userspace or when entering
> or leaving the kernel space.
>
> The livepatch is a bit tricky:
> 1. The syscall function name is architecture specific. Also
> ARCH_HAS_SYSCALL_WRAPPER must be taken in account.
>
> 2. The syscall must stay working the same way for other processes
> on the system. It is solved by decrementing a counter only
> for PIDs of the test processes. It means that the test processes
> has to call the livepatched syscall at least once.
>
> The test creates one userspace process per online cpu. The processes
> are calling getpid in a busy loop. The intention is to create random
> locations when the livepatch gets enabled. Nothing is guarantted.
> The magic is in the randomness.
>
> Signed-off-by: Marcos Paulo de Souza <[email protected]>
> ---
> tools/testing/selftests/livepatch/Makefile | 4 +-
> tools/testing/selftests/livepatch/test-syscall.sh | 53 ++++++++++
> .../selftests/livepatch/test_klp-call_getpid.c | 44 ++++++++
> .../selftests/livepatch/test_modules/Makefile | 3 +-
> .../livepatch/test_modules/test_klp_syscall.c | 116 +++++++++++++++++++++
> 5 files changed, 218 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
> index 119e2bbebe5d..35418a4790be 100644
> --- a/tools/testing/selftests/livepatch/Makefile
> +++ b/tools/testing/selftests/livepatch/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
>
> +TEST_GEN_FILES := test_klp-call_getpid
> TEST_GEN_MODS_DIR := test_modules
> TEST_PROGS_EXTENDED := functions.sh
> TEST_PROGS := \
> @@ -8,7 +9,8 @@ TEST_PROGS := \
> test-shadow-vars.sh \
> test-state.sh \
> test-ftrace.sh \
> - test-sysfs.sh
> + test-sysfs.sh \
> + test-syscall.sh
>
> TEST_FILES := settings
>
> diff --git a/tools/testing/selftests/livepatch/test-syscall.sh b/tools/testing/selftests/livepatch/test-syscall.sh
> new file mode 100755
> index 000000000000..b76a881d4013
> --- /dev/null
> +++ b/tools/testing/selftests/livepatch/test-syscall.sh
> @@ -0,0 +1,53 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (C) 2023 SUSE
> +# Author: Marcos Paulo de Souza <[email protected]>
> +
> +. $(dirname $0)/functions.sh
> +
> +MOD_SYSCALL=test_klp_syscall
> +
> +setup_config
> +
> +# - Start _NRPROC processes calling getpid and load a livepatch to patch the
> +# getpid syscall. Check if all the processes transitioned to the livepatched
> +# state.
> +
> +start_test "patch getpid syscall while being heavily hammered"
> +
> +for i in $(seq 1 $(getconf _NPROCESSORS_ONLN)); do
> + ./test_klp-call_getpid &
> + pids[$i]="$!"
> +done
> +
> +pid_list=$(echo ${pids[@]} | tr ' ' ',')
> +load_lp $MOD_SYSCALL klp_pids=$pid_list
> +
> +# wait for all tasks to transition to patched state
> +loop_until 'grep -q '^0$' /sys/kernel/test_klp_syscall/npids'
> +
> +pending_pids=$(cat /sys/kernel/test_klp_syscall/npids)
> +log "$MOD_SYSCALL: Remaining not livepatched processes: $pending_pids"
> +
> +for pid in ${pids[@]}; do
> + kill $pid || true
> +done
> +
> +disable_lp $MOD_SYSCALL
> +unload_lp $MOD_SYSCALL
> +
> +check_result "% insmod test_modules/$MOD_SYSCALL.ko klp_pids=$pid_list
> +livepatch: enabling patch '$MOD_SYSCALL'
> +livepatch: '$MOD_SYSCALL': initializing patching transition
> +livepatch: '$MOD_SYSCALL': starting patching transition
> +livepatch: '$MOD_SYSCALL': completing patching transition
> +livepatch: '$MOD_SYSCALL': patching complete
> +$MOD_SYSCALL: Remaining not livepatched processes: 0
> +% echo 0 > /sys/kernel/livepatch/$MOD_SYSCALL/enabled
> +livepatch: '$MOD_SYSCALL': initializing unpatching transition
> +livepatch: '$MOD_SYSCALL': starting unpatching transition
> +livepatch: '$MOD_SYSCALL': completing unpatching transition
> +livepatch: '$MOD_SYSCALL': unpatching complete
> +% rmmod $MOD_SYSCALL"
> +
> +exit 0
> diff --git a/tools/testing/selftests/livepatch/test_klp-call_getpid.c b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
> new file mode 100644
> index 000000000000..ce321a2d7308
> --- /dev/null
> +++ b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
> @@ -0,0 +1,44 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2023 SUSE
> + * Authors: Libor Pechacek <[email protected]>
> + * Marcos Paulo de Souza <[email protected]>
> + */
> +
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <sys/syscall.h>
> +#include <sys/types.h>
> +#include <signal.h>
> +
> +static int stop;
> +static int sig_int;
> +
> +void hup_handler(int signum)
> +{
> + stop = 1;
> +}
> +
> +void int_handler(int signum)
> +{
> + stop = 1;
> + sig_int = 1;
> +}
> +
> +int main(int argc, char *argv[])
> +{
> + long count = 0;
> +
> + signal(SIGHUP, &hup_handler);
> + signal(SIGINT, &int_handler);
> +
> + while (!stop) {
> + (void)syscall(SYS_getpid);
> + count++;
> + }
> +
> + if (sig_int)
> + printf("%ld iterations done\n", count);
> +
> + return 0;
> +}
> diff --git a/tools/testing/selftests/livepatch/test_modules/Makefile b/tools/testing/selftests/livepatch/test_modules/Makefile
> index 6f7c2103d27d..f5e880269bff 100644
> --- a/tools/testing/selftests/livepatch/test_modules/Makefile
> +++ b/tools/testing/selftests/livepatch/test_modules/Makefile
> @@ -10,7 +10,8 @@ obj-m += test_klp_atomic_replace.o \
> test_klp_state.o \
> test_klp_state2.o \
> test_klp_state3.o \
> - test_klp_shadow_vars.o
> + test_klp_shadow_vars.o \
> + test_klp_syscall.o
>
> modules:
> $(Q)$(MAKE) -C $(KDIR) modules KBUILD_EXTMOD=$(TESTMODS_DIR)
> diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
> new file mode 100644
> index 000000000000..619496cc3481
> --- /dev/null
> +++ b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
> @@ -0,0 +1,116 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2017-2023 SUSE
> + * Authors: Libor Pechacek <[email protected]>
> + * Nicolai Stange <[email protected]>
> + * Marcos Paulo de Souza <[email protected]>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/sched.h>
> +#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_
> +#else
> +/* powerpc does not select ARCH_HAS_SYSCALL_WRAPPER */
> +#define FN_PREFIX
> +#endif
> +
> +/* Protects klp_pids */
> +static DEFINE_MUTEX(kpid_mutex);
> +
> +static unsigned int npids, npids_pending;
> +static int klp_pids[NR_CPUS];
> +module_param_array(klp_pids, int, &npids_pending, 0);
> +MODULE_PARM_DESC(klp_pids, "Array of pids to be transitioned to livepatched state.");
> +
> +static ssize_t npids_show(struct kobject *kobj, struct kobj_attribute *attr,
> + char *buf)
> +{
> + return sprintf(buf, "%u\n", npids_pending);
> +}
> +
> +static struct kobj_attribute klp_attr = __ATTR_RO(npids);
> +static struct kobject *klp_kobj;
> +
> +asmlinkage long lp_sys_getpid(void)
> +{
> + int i;
> +
> + mutex_lock(&kpid_mutex);
> + if (npids_pending > 0) {
> + for (i = 0; i < npids; i++) {
> + if (current->pid == klp_pids[i]) {
> + klp_pids[i] = 0;
> + npids_pending--;
> + break;
> + }
> + }
> + }
> + mutex_unlock(&kpid_mutex);
> +
> + return task_tgid_vnr(current);
> +}
> +
> +static struct klp_func vmlinux_funcs[] = {
> + {
> + .old_name = __stringify(FN_PREFIX) "sys_getpid",
> + .new_func = lp_sys_getpid,
> + }, {}
> +};
> +
> +static struct klp_object objs[] = {
> + {
> + /* name being NULL means vmlinux */
> + .funcs = vmlinux_funcs,
> + }, {}
> +};
> +
> +static struct klp_patch patch = {
> + .mod = THIS_MODULE,
> + .objs = objs,
> +};
> +
> +static int livepatch_init(void)
> +{
> + int ret;
> +
> + klp_kobj = kobject_create_and_add("test_klp_syscall", kernel_kobj);
> + if (!klp_kobj)
> + return -ENOMEM;
> +
> + ret = sysfs_create_file(klp_kobj, &klp_attr.attr);
> + if (ret) {
> + kobject_put(klp_kobj);
> + return ret;
> + }
> +
> + /*
> + * Save the number pids to transition to livepatched state before the
> + * number of pending pids is decremented.
> + */
> + npids = npids_pending;
> +
> + return klp_enable_patch(&patch);
> +}
> +
> +static void livepatch_exit(void)
> +{
> + kobject_put(klp_kobj);
> +}
> +
> +module_init(livepatch_init);
> +module_exit(livepatch_exit);
> +MODULE_LICENSE("GPL");
> +MODULE_INFO(livepatch, "Y");
> +MODULE_AUTHOR("Libor Pechacek <[email protected]>");
> +MODULE_AUTHOR("Nicolai Stange <[email protected]>");
> +MODULE_AUTHOR("Marcos Paulo de Souza <[email protected]>");
> +MODULE_DESCRIPTION("Livepatch test: syscall transition");

Missing module name? Is there a reason to not name this module?

thanks,
-- Shuah

2023-12-01 13:13:43

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On Thu, Nov 30, 2023 at 04:24:26PM -0700, Shuah Khan wrote:
> On 10/31/23 15:10, Marcos Paulo de Souza wrote:
> > The test proves that a syscall can be livepatched. It is interesting
> > because syscalls are called a tricky way. Also the process gets
> > livepatched either when sleeping in the userspace or when entering
> > or leaving the kernel space.
> >
> > The livepatch is a bit tricky:
> > 1. The syscall function name is architecture specific. Also
> > ARCH_HAS_SYSCALL_WRAPPER must be taken in account.
> >
> > 2. The syscall must stay working the same way for other processes
> > on the system. It is solved by decrementing a counter only
> > for PIDs of the test processes. It means that the test processes
> > has to call the livepatched syscall at least once.
> >
> > The test creates one userspace process per online cpu. The processes
> > are calling getpid in a busy loop. The intention is to create random
> > locations when the livepatch gets enabled. Nothing is guarantted.
> > The magic is in the randomness.
> >
> > Signed-off-by: Marcos Paulo de Souza <[email protected]>
> > ---
> > tools/testing/selftests/livepatch/Makefile | 4 +-
> > tools/testing/selftests/livepatch/test-syscall.sh | 53 ++++++++++
> > .../selftests/livepatch/test_klp-call_getpid.c | 44 ++++++++
> > .../selftests/livepatch/test_modules/Makefile | 3 +-
> > .../livepatch/test_modules/test_klp_syscall.c | 116 +++++++++++++++++++++
> > 5 files changed, 218 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
> > index 119e2bbebe5d..35418a4790be 100644
> > --- a/tools/testing/selftests/livepatch/Makefile
> > +++ b/tools/testing/selftests/livepatch/Makefile
> > @@ -1,5 +1,6 @@
> > # SPDX-License-Identifier: GPL-2.0
> > +TEST_GEN_FILES := test_klp-call_getpid
> > TEST_GEN_MODS_DIR := test_modules
> > TEST_PROGS_EXTENDED := functions.sh
> > TEST_PROGS := \
> > @@ -8,7 +9,8 @@ TEST_PROGS := \
> > test-shadow-vars.sh \
> > test-state.sh \
> > test-ftrace.sh \
> > - test-sysfs.sh
> > + test-sysfs.sh \
> > + test-syscall.sh
> > TEST_FILES := settings
> > diff --git a/tools/testing/selftests/livepatch/test-syscall.sh b/tools/testing/selftests/livepatch/test-syscall.sh
> > new file mode 100755
> > index 000000000000..b76a881d4013
> > --- /dev/null
> > +++ b/tools/testing/selftests/livepatch/test-syscall.sh
> > @@ -0,0 +1,53 @@
> > +#!/bin/bash
> > +# SPDX-License-Identifier: GPL-2.0
> > +# Copyright (C) 2023 SUSE
> > +# Author: Marcos Paulo de Souza <[email protected]>
> > +
> > +. $(dirname $0)/functions.sh
> > +
> > +MOD_SYSCALL=test_klp_syscall
> > +
> > +setup_config
> > +
> > +# - Start _NRPROC processes calling getpid and load a livepatch to patch the
> > +# getpid syscall. Check if all the processes transitioned to the livepatched
> > +# state.
> > +
> > +start_test "patch getpid syscall while being heavily hammered"
> > +
> > +for i in $(seq 1 $(getconf _NPROCESSORS_ONLN)); do
> > + ./test_klp-call_getpid &
> > + pids[$i]="$!"
> > +done
> > +
> > +pid_list=$(echo ${pids[@]} | tr ' ' ',')
> > +load_lp $MOD_SYSCALL klp_pids=$pid_list
> > +
> > +# wait for all tasks to transition to patched state
> > +loop_until 'grep -q '^0$' /sys/kernel/test_klp_syscall/npids'
> > +
> > +pending_pids=$(cat /sys/kernel/test_klp_syscall/npids)
> > +log "$MOD_SYSCALL: Remaining not livepatched processes: $pending_pids"
> > +
> > +for pid in ${pids[@]}; do
> > + kill $pid || true
> > +done
> > +
> > +disable_lp $MOD_SYSCALL
> > +unload_lp $MOD_SYSCALL
> > +
> > +check_result "% insmod test_modules/$MOD_SYSCALL.ko klp_pids=$pid_list
> > +livepatch: enabling patch '$MOD_SYSCALL'
> > +livepatch: '$MOD_SYSCALL': initializing patching transition
> > +livepatch: '$MOD_SYSCALL': starting patching transition
> > +livepatch: '$MOD_SYSCALL': completing patching transition
> > +livepatch: '$MOD_SYSCALL': patching complete
> > +$MOD_SYSCALL: Remaining not livepatched processes: 0
> > +% echo 0 > /sys/kernel/livepatch/$MOD_SYSCALL/enabled
> > +livepatch: '$MOD_SYSCALL': initializing unpatching transition
> > +livepatch: '$MOD_SYSCALL': starting unpatching transition
> > +livepatch: '$MOD_SYSCALL': completing unpatching transition
> > +livepatch: '$MOD_SYSCALL': unpatching complete
> > +% rmmod $MOD_SYSCALL"
> > +
> > +exit 0
> > diff --git a/tools/testing/selftests/livepatch/test_klp-call_getpid.c b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
> > new file mode 100644
> > index 000000000000..ce321a2d7308
> > --- /dev/null
> > +++ b/tools/testing/selftests/livepatch/test_klp-call_getpid.c
> > @@ -0,0 +1,44 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2023 SUSE
> > + * Authors: Libor Pechacek <[email protected]>
> > + * Marcos Paulo de Souza <[email protected]>
> > + */
> > +
> > +#include <stdio.h>
> > +#include <unistd.h>
> > +#include <sys/syscall.h>
> > +#include <sys/types.h>
> > +#include <signal.h>
> > +
> > +static int stop;
> > +static int sig_int;
> > +
> > +void hup_handler(int signum)
> > +{
> > + stop = 1;
> > +}
> > +
> > +void int_handler(int signum)
> > +{
> > + stop = 1;
> > + sig_int = 1;
> > +}
> > +
> > +int main(int argc, char *argv[])
> > +{
> > + long count = 0;
> > +
> > + signal(SIGHUP, &hup_handler);
> > + signal(SIGINT, &int_handler);
> > +
> > + while (!stop) {
> > + (void)syscall(SYS_getpid);
> > + count++;
> > + }
> > +
> > + if (sig_int)
> > + printf("%ld iterations done\n", count);
> > +
> > + return 0;
> > +}
> > diff --git a/tools/testing/selftests/livepatch/test_modules/Makefile b/tools/testing/selftests/livepatch/test_modules/Makefile
> > index 6f7c2103d27d..f5e880269bff 100644
> > --- a/tools/testing/selftests/livepatch/test_modules/Makefile
> > +++ b/tools/testing/selftests/livepatch/test_modules/Makefile
> > @@ -10,7 +10,8 @@ obj-m += test_klp_atomic_replace.o \
> > test_klp_state.o \
> > test_klp_state2.o \
> > test_klp_state3.o \
> > - test_klp_shadow_vars.o
> > + test_klp_shadow_vars.o \
> > + test_klp_syscall.o
> > modules:
> > $(Q)$(MAKE) -C $(KDIR) modules KBUILD_EXTMOD=$(TESTMODS_DIR)
> > diff --git a/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
> > new file mode 100644
> > index 000000000000..619496cc3481
> > --- /dev/null
> > +++ b/tools/testing/selftests/livepatch/test_modules/test_klp_syscall.c
> > @@ -0,0 +1,116 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2017-2023 SUSE
> > + * Authors: Libor Pechacek <[email protected]>
> > + * Nicolai Stange <[email protected]>
> > + * Marcos Paulo de Souza <[email protected]>
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/kernel.h>
> > +#include <linux/sched.h>
> > +#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_
> > +#else
> > +/* powerpc does not select ARCH_HAS_SYSCALL_WRAPPER */
> > +#define FN_PREFIX
> > +#endif
> > +
> > +/* Protects klp_pids */
> > +static DEFINE_MUTEX(kpid_mutex);
> > +
> > +static unsigned int npids, npids_pending;
> > +static int klp_pids[NR_CPUS];
> > +module_param_array(klp_pids, int, &npids_pending, 0);
> > +MODULE_PARM_DESC(klp_pids, "Array of pids to be transitioned to livepatched state.");
> > +
> > +static ssize_t npids_show(struct kobject *kobj, struct kobj_attribute *attr,
> > + char *buf)
> > +{
> > + return sprintf(buf, "%u\n", npids_pending);
> > +}
> > +
> > +static struct kobj_attribute klp_attr = __ATTR_RO(npids);
> > +static struct kobject *klp_kobj;
> > +
> > +asmlinkage long lp_sys_getpid(void)
> > +{
> > + int i;
> > +
> > + mutex_lock(&kpid_mutex);
> > + if (npids_pending > 0) {
> > + for (i = 0; i < npids; i++) {
> > + if (current->pid == klp_pids[i]) {
> > + klp_pids[i] = 0;
> > + npids_pending--;
> > + break;
> > + }
> > + }
> > + }
> > + mutex_unlock(&kpid_mutex);
> > +
> > + return task_tgid_vnr(current);
> > +}
> > +
> > +static struct klp_func vmlinux_funcs[] = {
> > + {
> > + .old_name = __stringify(FN_PREFIX) "sys_getpid",
> > + .new_func = lp_sys_getpid,
> > + }, {}
> > +};
> > +
> > +static struct klp_object objs[] = {
> > + {
> > + /* name being NULL means vmlinux */
> > + .funcs = vmlinux_funcs,
> > + }, {}
> > +};
> > +
> > +static struct klp_patch patch = {
> > + .mod = THIS_MODULE,
> > + .objs = objs,
> > +};
> > +
> > +static int livepatch_init(void)
> > +{
> > + int ret;
> > +
> > + klp_kobj = kobject_create_and_add("test_klp_syscall", kernel_kobj);
> > + if (!klp_kobj)
> > + return -ENOMEM;
> > +
> > + ret = sysfs_create_file(klp_kobj, &klp_attr.attr);
> > + if (ret) {
> > + kobject_put(klp_kobj);
> > + return ret;
> > + }
> > +
> > + /*
> > + * Save the number pids to transition to livepatched state before the
> > + * number of pending pids is decremented.
> > + */
> > + npids = npids_pending;
> > +
> > + return klp_enable_patch(&patch);
> > +}
> > +
> > +static void livepatch_exit(void)
> > +{
> > + kobject_put(klp_kobj);
> > +}
> > +
> > +module_init(livepatch_init);
> > +module_exit(livepatch_exit);
> > +MODULE_LICENSE("GPL");
> > +MODULE_INFO(livepatch, "Y");
> > +MODULE_AUTHOR("Libor Pechacek <[email protected]>");
> > +MODULE_AUTHOR("Nicolai Stange <[email protected]>");
> > +MODULE_AUTHOR("Marcos Paulo de Souza <[email protected]>");
> > +MODULE_DESCRIPTION("Livepatch test: syscall transition");
>
> Missing module name? Is there a reason to not name this module?

Can you please elaborate? This new module use the same MODULE_ macros used by
the current livepatch selftests. What do you mean by module name?

Thanks in advance,
Marcos

>
> thanks,
> -- Shuah

2023-12-01 15:28:43

by Joe Lawrence

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de Souza wrote:
> The modules are being moved from lib/livepatch to
> tools/testing/selftests/livepatch/test_modules.
>
> This code moving will allow writing more complex tests, like for example an
> userspace C code that will call a livepatched kernel function.
>
> The modules are now built as out-of-tree
> modules, but being part of the kernel source means they will be maintained.
>
> Another advantage of the code moving is to be able to easily change,
> debug and rebuild the tests by running make on the selftests/livepatch directory,
> which is not currently possible since the modules on lib/livepatch are
> build and installed using the "modules" target.
>
> The current approach also keeps the ability to execute the tests manually by
> executing the scripts inside selftests/livepatch directory, as it's currently
> supported. If the modules are modified, they needed to be rebuilt before running
> the scripts though.
>
> The modules are built before running the selftests when using the
> kselftest invocations:
>
> make kselftest TARGETS=livepatch
> or
> make -C tools/testing/selftests/livepatch run_tests
>

Quick question:

- We have been building with CONFIG_LIVEPATCH_TEST=m to generate the
test modules at kernel build time

- Our packaging filters out the selftest scripts and supporting modules
from the general kernel RPM package into their subpackages

- Tests are run as part of CKI or other manual tests by installing the
pre-built packages from the previous step


After this patch, we would need to add something like the following to
our kernel build, before packaging:

$ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
^^^^

If this is the correct way to build the test modules for *this* tree and
/lib/modules/$(shell uname -r)/build... it might be useful to document
in the commit message as an alternative use case.

-- Joe

> Having the modules being built as out-of-modules requires changing the
> currently
> used 'modprobe' by 'insmod' and adapt the test scripts that check for the kernel
> message buffer.
>
> As there aren't any modules being built on lib/livepatch, remove the
> TEST_LIVEPATCH Kconfig and it's references.
>
> Note: "make gen_tar" packages the pre-built binaries into the tarball.
> It means that it will store the test modules pre-built for
> the kernel running on the build host.
>
> Note that these modules need not binary compatible with
> the kernel built from the same sources. But the same
> is true for other packaged selftest binaries.
>
> The entire kernel sources are needed for rebuilding
> the selftests on another system.
>
> Signed-off-by: Marcos Paulo de Souza <[email protected]>
> ---
> arch/s390/configs/debug_defconfig | 1 -
> arch/s390/configs/defconfig | 1 -
> lib/Kconfig.debug | 22 ----------
> lib/Makefile | 2 -
> lib/livepatch/Makefile | 14 ------
> tools/testing/selftests/livepatch/Makefile | 1 +
> tools/testing/selftests/livepatch/README | 17 +++++---
> tools/testing/selftests/livepatch/config | 1 -
> tools/testing/selftests/livepatch/functions.sh | 34 ++++++---------
> .../testing/selftests/livepatch/test-callbacks.sh | 50 +++++++++++-----------
> tools/testing/selftests/livepatch/test-ftrace.sh | 6 +--
> .../testing/selftests/livepatch/test-livepatch.sh | 10 ++---
> .../selftests/livepatch/test-shadow-vars.sh | 2 +-
> tools/testing/selftests/livepatch/test-state.sh | 18 ++++----
> tools/testing/selftests/livepatch/test-sysfs.sh | 6 +--
> .../selftests/livepatch/test_modules/Makefile | 19 ++++++++
> .../test_modules}/test_klp_atomic_replace.c | 0
> .../test_modules}/test_klp_callbacks_busy.c | 0
> .../test_modules}/test_klp_callbacks_demo.c | 0
> .../test_modules}/test_klp_callbacks_demo2.c | 0
> .../test_modules}/test_klp_callbacks_mod.c | 0
> .../livepatch/test_modules}/test_klp_livepatch.c | 0
> .../livepatch/test_modules}/test_klp_shadow_vars.c | 0
> .../livepatch/test_modules}/test_klp_state.c | 0
> .../livepatch/test_modules}/test_klp_state2.c | 0
> .../livepatch/test_modules}/test_klp_state3.c | 0
> 26 files changed, 89 insertions(+), 115 deletions(-)
>
> diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
> index 438cd92e6080..9672b9f31710 100644
> --- a/arch/s390/configs/debug_defconfig
> +++ b/arch/s390/configs/debug_defconfig
> @@ -885,4 +885,3 @@ CONFIG_ATOMIC64_SELFTEST=y
> CONFIG_STRING_SELFTEST=y
> CONFIG_TEST_BITOPS=m
> CONFIG_TEST_BPF=m
> -CONFIG_TEST_LIVEPATCH=m
> diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
> index 1b8150e50f6a..a8a66264a72d 100644
> --- a/arch/s390/configs/defconfig
> +++ b/arch/s390/configs/defconfig
> @@ -813,4 +813,3 @@ CONFIG_KPROBES_SANITY_TEST=m
> CONFIG_PERCPU_TEST=m
> CONFIG_ATOMIC64_SELFTEST=y
> CONFIG_TEST_BPF=m
> -CONFIG_TEST_LIVEPATCH=m
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index fa307f93fa2e..af67c5f5d031 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2862,28 +2862,6 @@ config TEST_MEMCAT_P
>
> If unsure, say N.
>
> -config TEST_LIVEPATCH
> - tristate "Test livepatching"
> - default n
> - depends on DYNAMIC_DEBUG
> - depends on LIVEPATCH
> - depends on m
> - help
> - Test kernel livepatching features for correctness. The tests will
> - load test modules that will be livepatched in various scenarios.
> -
> - To run all the livepatching tests:
> -
> - make -C tools/testing/selftests TARGETS=livepatch run_tests
> -
> - Alternatively, individual tests may be invoked:
> -
> - tools/testing/selftests/livepatch/test-callbacks.sh
> - tools/testing/selftests/livepatch/test-livepatch.sh
> - tools/testing/selftests/livepatch/test-shadow-vars.sh
> -
> - If unsure, say N.
> -
> config TEST_OBJAGG
> tristate "Perform selftest on object aggreration manager"
> default n
> diff --git a/lib/Makefile b/lib/Makefile
> index 740109b6e2c8..b96b280787ca 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -132,8 +132,6 @@ endif
> obj-$(CONFIG_TEST_FPU) += test_fpu.o
> CFLAGS_test_fpu.o += $(FPU_CFLAGS)
>
> -obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/
> -
> # Some KUnit files (hooks.o) need to be built-in even when KUnit is a module,
> # so we can't just use obj-$(CONFIG_KUNIT).
> ifdef CONFIG_KUNIT
> diff --git a/lib/livepatch/Makefile b/lib/livepatch/Makefile
> deleted file mode 100644
> index dcc912b3478f..000000000000
> --- a/lib/livepatch/Makefile
> +++ /dev/null
> @@ -1,14 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0
> -#
> -# Makefile for livepatch test code.
> -
> -obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \
> - test_klp_callbacks_demo.o \
> - test_klp_callbacks_demo2.o \
> - test_klp_callbacks_busy.o \
> - test_klp_callbacks_mod.o \
> - test_klp_livepatch.o \
> - test_klp_shadow_vars.o \
> - test_klp_state.o \
> - test_klp_state2.o \
> - test_klp_state3.o
> diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile
> index 02fadc9d55e0..119e2bbebe5d 100644
> --- a/tools/testing/selftests/livepatch/Makefile
> +++ b/tools/testing/selftests/livepatch/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
>
> +TEST_GEN_MODS_DIR := test_modules
> TEST_PROGS_EXTENDED := functions.sh
> TEST_PROGS := \
> test-livepatch.sh \
> diff --git a/tools/testing/selftests/livepatch/README b/tools/testing/selftests/livepatch/README
> index 0942dd5826f8..c5eb3cb67b66 100644
> --- a/tools/testing/selftests/livepatch/README
> +++ b/tools/testing/selftests/livepatch/README
> @@ -13,23 +13,26 @@ the message buffer for only the duration of each individual test.)
> Config
> ------
>
> -Set these config options and their prerequisites:
> -
> -CONFIG_LIVEPATCH=y
> -CONFIG_TEST_LIVEPATCH=m
> +Set CONFIG_LIVEPATCH=y option and it's prerequisites.
>
>
> Running the tests
> -----------------
>
> -Test kernel modules are built as part of lib/ (make modules) and need to
> -be installed (make modules_install) as the test scripts will modprobe
> -them.
> +Test kernel modules are built before running the livepatch selftests. The
> +modules are located under test_modules directory, and are built as out-of-tree
> +modules. This is specially useful since the same sources can be built and
> +tested on systems with different kABI, ensuring they the tests are backwards
> +compatible. The modules will be loaded by the test scripts using insmod.
>
> To run the livepatch selftests, from the top of the kernel source tree:
>
> % make -C tools/testing/selftests TARGETS=livepatch run_tests
>
> +or
> +
> + % make kselftest TARGETS=livepatch
> +
>
> Adding tests
> ------------
> diff --git a/tools/testing/selftests/livepatch/config b/tools/testing/selftests/livepatch/config
> index ad23100cb27c..e88bf518a23a 100644
> --- a/tools/testing/selftests/livepatch/config
> +++ b/tools/testing/selftests/livepatch/config
> @@ -1,3 +1,2 @@
> CONFIG_LIVEPATCH=y
> CONFIG_DYNAMIC_DEBUG=y
> -CONFIG_TEST_LIVEPATCH=m
> diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
> index c8416c54b463..e60cf09491a6 100644
> --- a/tools/testing/selftests/livepatch/functions.sh
> +++ b/tools/testing/selftests/livepatch/functions.sh
> @@ -127,16 +127,14 @@ function loop_until() {
> done
> }
>
> -function assert_mod() {
> - local mod="$1"
> -
> - modprobe --dry-run "$mod" &>/dev/null
> -}
> -
> function is_livepatch_mod() {
> local mod="$1"
>
> - if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then
> + if [[ ! -f "test_modules/$mod.ko" ]]; then
> + die "Can't find \"test_modules/$mod.ko\", try \"make\""
> + fi
> +
> + if [[ $(modinfo "test_modules/$mod.ko" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then
> return 0
> fi
>
> @@ -146,9 +144,9 @@ function is_livepatch_mod() {
> function __load_mod() {
> local mod="$1"; shift
>
> - local msg="% modprobe $mod $*"
> + local msg="% insmod test_modules/$mod.ko $*"
> log "${msg%% }"
> - ret=$(modprobe "$mod" "$@" 2>&1)
> + ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
> if [[ "$ret" != "" ]]; then
> die "$ret"
> fi
> @@ -161,13 +159,10 @@ function __load_mod() {
>
> # load_mod(modname, params) - load a kernel module
> # modname - module name to load
> -# params - module parameters to pass to modprobe
> +# params - module parameters to pass to insmod
> function load_mod() {
> local mod="$1"; shift
>
> - assert_mod "$mod" ||
> - skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
> -
> is_livepatch_mod "$mod" &&
> die "use load_lp() to load the livepatch module $mod"
>
> @@ -177,13 +172,10 @@ function load_mod() {
> # load_lp_nowait(modname, params) - load a kernel module with a livepatch
> # but do not wait on until the transition finishes
> # modname - module name to load
> -# params - module parameters to pass to modprobe
> +# params - module parameters to pass to insmod
> function load_lp_nowait() {
> local mod="$1"; shift
>
> - assert_mod "$mod" ||
> - skip "unable to load module ${mod}, verify CONFIG_TEST_LIVEPATCH=m and run self-tests as root"
> -
> is_livepatch_mod "$mod" ||
> die "module $mod is not a livepatch"
>
> @@ -196,7 +188,7 @@ function load_lp_nowait() {
>
> # load_lp(modname, params) - load a kernel module with a livepatch
> # modname - module name to load
> -# params - module parameters to pass to modprobe
> +# params - module parameters to pass to insmod
> function load_lp() {
> local mod="$1"; shift
>
> @@ -209,13 +201,13 @@ function load_lp() {
>
> # load_failing_mod(modname, params) - load a kernel module, expect to fail
> # modname - module name to load
> -# params - module parameters to pass to modprobe
> +# params - module parameters to pass to insmod
> function load_failing_mod() {
> local mod="$1"; shift
>
> - local msg="% modprobe $mod $*"
> + local msg="% insmod test_modules/$mod.ko $*"
> log "${msg%% }"
> - ret=$(modprobe "$mod" "$@" 2>&1)
> + ret=$(insmod "test_modules/$mod.ko" "$@" 2>&1)
> if [[ "$ret" == "" ]]; then
> die "$mod unexpectedly loaded"
> fi
> diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh
> index 90b26dbb2626..32b150e25b10 100755
> --- a/tools/testing/selftests/livepatch/test-callbacks.sh
> +++ b/tools/testing/selftests/livepatch/test-callbacks.sh
> @@ -34,9 +34,9 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
> unload_mod $MOD_TARGET
>
> -check_result "% modprobe $MOD_TARGET
> +check_result "% insmod test_modules/$MOD_TARGET.ko
> $MOD_TARGET: ${MOD_TARGET}_init
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -81,7 +81,7 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
> unload_mod $MOD_TARGET
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -89,7 +89,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_TARGET
> +% insmod test_modules/$MOD_TARGET.ko
> livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> $MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> @@ -129,9 +129,9 @@ unload_mod $MOD_TARGET
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_TARGET
> +check_result "% insmod test_modules/$MOD_TARGET.ko
> $MOD_TARGET: ${MOD_TARGET}_init
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -177,7 +177,7 @@ unload_mod $MOD_TARGET
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -185,7 +185,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_TARGET
> +% insmod test_modules/$MOD_TARGET.ko
> livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> $MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> @@ -219,7 +219,7 @@ load_lp $MOD_LIVEPATCH
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -254,9 +254,9 @@ load_mod $MOD_TARGET
> load_failing_mod $MOD_LIVEPATCH pre_patch_ret=-19
> unload_mod $MOD_TARGET
>
> -check_result "% modprobe $MOD_TARGET
> +check_result "% insmod test_modules/$MOD_TARGET.ko
> $MOD_TARGET: ${MOD_TARGET}_init
> -% modprobe $MOD_LIVEPATCH pre_patch_ret=-19
> +% insmod test_modules/$MOD_LIVEPATCH.ko pre_patch_ret=-19
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> test_klp_callbacks_demo: pre_patch_callback: vmlinux
> @@ -265,7 +265,7 @@ livepatch: failed to enable patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': canceling patching transition, going to unpatch
> livepatch: '$MOD_LIVEPATCH': completing unpatching transition
> livepatch: '$MOD_LIVEPATCH': unpatching complete
> -modprobe: ERROR: could not insert '$MOD_LIVEPATCH': No such device
> +insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: No such device
> % rmmod $MOD_TARGET
> $MOD_TARGET: ${MOD_TARGET}_exit"
>
> @@ -295,7 +295,7 @@ load_failing_mod $MOD_TARGET
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -304,12 +304,12 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> livepatch: '$MOD_LIVEPATCH': patching complete
> % echo -19 > /sys/module/$MOD_LIVEPATCH/parameters/pre_patch_ret
> -% modprobe $MOD_TARGET
> +% insmod test_modules/$MOD_TARGET.ko
> livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> livepatch: pre-patch callback failed for object '$MOD_TARGET'
> livepatch: patch '$MOD_LIVEPATCH' failed for module '$MOD_TARGET', refusing to load module '$MOD_TARGET'
> -modprobe: ERROR: could not insert '$MOD_TARGET': No such device
> +insmod: ERROR: could not insert module test_modules/$MOD_TARGET.ko: No such device
> % echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled
> livepatch: '$MOD_LIVEPATCH': initializing unpatching transition
> $MOD_LIVEPATCH: pre_unpatch_callback: vmlinux
> @@ -340,11 +340,11 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
> unload_mod $MOD_TARGET_BUSY
>
> -check_result "% modprobe $MOD_TARGET_BUSY block_transition=N
> +check_result "% insmod test_modules/$MOD_TARGET_BUSY.ko block_transition=N
> $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init
> $MOD_TARGET_BUSY: busymod_work_func enter
> $MOD_TARGET_BUSY: busymod_work_func exit
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -354,7 +354,7 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> $MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_TARGET
> +% insmod test_modules/$MOD_TARGET.ko
> livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> $MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> @@ -421,16 +421,16 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
> unload_mod $MOD_TARGET_BUSY
>
> -check_result "% modprobe $MOD_TARGET_BUSY block_transition=Y
> +check_result "% insmod test_modules/$MOD_TARGET_BUSY.ko block_transition=Y
> $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init
> $MOD_TARGET_BUSY: busymod_work_func enter
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> -% modprobe $MOD_TARGET
> +% insmod test_modules/$MOD_TARGET.ko
> livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET'
> $MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init
> $MOD_TARGET: ${MOD_TARGET}_init
> @@ -467,7 +467,7 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -475,7 +475,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_LIVEPATCH2
> +% insmod test_modules/$MOD_LIVEPATCH2.ko
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> @@ -523,7 +523,7 @@ disable_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -531,7 +531,7 @@ livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_LIVEPATCH2 replace=1
> +% insmod test_modules/$MOD_LIVEPATCH2.ko replace=1
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh
> index 825540a5194d..730218bce99c 100755
> --- a/tools/testing/selftests/livepatch/test-ftrace.sh
> +++ b/tools/testing/selftests/livepatch/test-ftrace.sh
> @@ -35,7 +35,7 @@ disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> check_result "livepatch: kernel.ftrace_enabled = 0
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: failed to register ftrace handler for function 'cmdline_proc_show' (-16)
> @@ -44,9 +44,9 @@ livepatch: failed to enable patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': canceling patching transition, going to unpatch
> livepatch: '$MOD_LIVEPATCH': completing unpatching transition
> livepatch: '$MOD_LIVEPATCH': unpatching complete
> -modprobe: ERROR: could not insert '$MOD_LIVEPATCH': Device or resource busy
> +insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: Device or resource busy
> livepatch: kernel.ftrace_enabled = 1
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> diff --git a/tools/testing/selftests/livepatch/test-livepatch.sh b/tools/testing/selftests/livepatch/test-livepatch.sh
> index 5fe79ac34be1..e3455a6b1158 100755
> --- a/tools/testing/selftests/livepatch/test-livepatch.sh
> +++ b/tools/testing/selftests/livepatch/test-livepatch.sh
> @@ -31,7 +31,7 @@ if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH: this has been live patched" ]]
> die "livepatch kselftest(s) failed"
> fi
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> @@ -75,14 +75,14 @@ unload_lp $MOD_LIVEPATCH
> grep 'live patched' /proc/cmdline > /dev/kmsg
> grep 'live patched' /proc/meminfo > /dev/kmsg
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> livepatch: '$MOD_LIVEPATCH': patching complete
> $MOD_LIVEPATCH: this has been live patched
> -% modprobe $MOD_REPLACE replace=0
> +% insmod test_modules/$MOD_REPLACE.ko replace=0
> livepatch: enabling patch '$MOD_REPLACE'
> livepatch: '$MOD_REPLACE': initializing patching transition
> livepatch: '$MOD_REPLACE': starting patching transition
> @@ -135,14 +135,14 @@ unload_lp $MOD_REPLACE
> grep 'live patched' /proc/cmdline > /dev/kmsg
> grep 'live patched' /proc/meminfo > /dev/kmsg
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> livepatch: '$MOD_LIVEPATCH': completing patching transition
> livepatch: '$MOD_LIVEPATCH': patching complete
> $MOD_LIVEPATCH: this has been live patched
> -% modprobe $MOD_REPLACE replace=1
> +% insmod test_modules/$MOD_REPLACE.ko replace=1
> livepatch: enabling patch '$MOD_REPLACE'
> livepatch: '$MOD_REPLACE': initializing patching transition
> livepatch: '$MOD_REPLACE': starting patching transition
> diff --git a/tools/testing/selftests/livepatch/test-shadow-vars.sh b/tools/testing/selftests/livepatch/test-shadow-vars.sh
> index e04cb354f56b..1218c155bffe 100755
> --- a/tools/testing/selftests/livepatch/test-shadow-vars.sh
> +++ b/tools/testing/selftests/livepatch/test-shadow-vars.sh
> @@ -16,7 +16,7 @@ start_test "basic shadow variable API"
> load_mod $MOD_TEST
> unload_mod $MOD_TEST
>
> -check_result "% modprobe $MOD_TEST
> +check_result "% insmod test_modules/$MOD_TEST.ko
> $MOD_TEST: klp_shadow_get(obj=PTR1, id=0x1234) = PTR0
> $MOD_TEST: got expected NULL result
> $MOD_TEST: shadow_ctor: PTR3 -> PTR2
> diff --git a/tools/testing/selftests/livepatch/test-state.sh b/tools/testing/selftests/livepatch/test-state.sh
> index 38656721c958..10a52ac06185 100755
> --- a/tools/testing/selftests/livepatch/test-state.sh
> +++ b/tools/testing/selftests/livepatch/test-state.sh
> @@ -19,7 +19,7 @@ load_lp $MOD_LIVEPATCH
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -51,7 +51,7 @@ unload_lp $MOD_LIVEPATCH
> disable_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH2
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> $MOD_LIVEPATCH: pre_patch_callback: vmlinux
> @@ -61,7 +61,7 @@ livepatch: '$MOD_LIVEPATCH': completing patching transition
> $MOD_LIVEPATCH: post_patch_callback: vmlinux
> $MOD_LIVEPATCH: fix_console_loglevel: fixing console_loglevel
> livepatch: '$MOD_LIVEPATCH': patching complete
> -% modprobe $MOD_LIVEPATCH2
> +% insmod test_modules/$MOD_LIVEPATCH2.ko
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> @@ -96,7 +96,7 @@ disable_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH3
>
> -check_result "% modprobe $MOD_LIVEPATCH2
> +check_result "% insmod test_modules/$MOD_LIVEPATCH2.ko
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> @@ -106,7 +106,7 @@ livepatch: '$MOD_LIVEPATCH2': completing patching transition
> $MOD_LIVEPATCH2: post_patch_callback: vmlinux
> $MOD_LIVEPATCH2: fix_console_loglevel: fixing console_loglevel
> livepatch: '$MOD_LIVEPATCH2': patching complete
> -% modprobe $MOD_LIVEPATCH3
> +% insmod test_modules/$MOD_LIVEPATCH3.ko
> livepatch: enabling patch '$MOD_LIVEPATCH3'
> livepatch: '$MOD_LIVEPATCH3': initializing patching transition
> $MOD_LIVEPATCH3: pre_patch_callback: vmlinux
> @@ -117,7 +117,7 @@ $MOD_LIVEPATCH3: post_patch_callback: vmlinux
> $MOD_LIVEPATCH3: fix_console_loglevel: taking over the console_loglevel change
> livepatch: '$MOD_LIVEPATCH3': patching complete
> % rmmod $MOD_LIVEPATCH2
> -% modprobe $MOD_LIVEPATCH2
> +% insmod test_modules/$MOD_LIVEPATCH2.ko
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> @@ -149,7 +149,7 @@ load_failing_mod $MOD_LIVEPATCH
> disable_lp $MOD_LIVEPATCH2
> unload_lp $MOD_LIVEPATCH2
>
> -check_result "% modprobe $MOD_LIVEPATCH2
> +check_result "% insmod test_modules/$MOD_LIVEPATCH2.ko
> livepatch: enabling patch '$MOD_LIVEPATCH2'
> livepatch: '$MOD_LIVEPATCH2': initializing patching transition
> $MOD_LIVEPATCH2: pre_patch_callback: vmlinux
> @@ -159,9 +159,9 @@ livepatch: '$MOD_LIVEPATCH2': completing patching transition
> $MOD_LIVEPATCH2: post_patch_callback: vmlinux
> $MOD_LIVEPATCH2: fix_console_loglevel: fixing console_loglevel
> livepatch: '$MOD_LIVEPATCH2': patching complete
> -% modprobe $MOD_LIVEPATCH
> +% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: Livepatch patch ($MOD_LIVEPATCH) is not compatible with the already installed livepatches.
> -modprobe: ERROR: could not insert '$MOD_LIVEPATCH': Invalid argument
> +insmod: ERROR: could not insert module test_modules/$MOD_LIVEPATCH.ko: Invalid parameters
> % echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH2/enabled
> livepatch: '$MOD_LIVEPATCH2': initializing unpatching transition
> $MOD_LIVEPATCH2: pre_unpatch_callback: vmlinux
> diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh
> index 7f76f280189a..6c646afa7395 100755
> --- a/tools/testing/selftests/livepatch/test-sysfs.sh
> +++ b/tools/testing/selftests/livepatch/test-sysfs.sh
> @@ -27,7 +27,7 @@ disable_lp $MOD_LIVEPATCH
>
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe $MOD_LIVEPATCH
> +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko
> livepatch: enabling patch '$MOD_LIVEPATCH'
> livepatch: '$MOD_LIVEPATCH': initializing patching transition
> livepatch: '$MOD_LIVEPATCH': starting patching transition
> @@ -56,7 +56,7 @@ check_sysfs_value "$MOD_LIVEPATCH" "$MOD_TARGET/patched" "0"
> disable_lp $MOD_LIVEPATCH
> unload_lp $MOD_LIVEPATCH
>
> -check_result "% modprobe test_klp_callbacks_demo
> +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
> @@ -64,7 +64,7 @@ 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
> -% modprobe test_klp_callbacks_mod
> +% 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
> diff --git a/tools/testing/selftests/livepatch/test_modules/Makefile b/tools/testing/selftests/livepatch/test_modules/Makefile
> new file mode 100644
> index 000000000000..6f7c2103d27d
> --- /dev/null
> +++ b/tools/testing/selftests/livepatch/test_modules/Makefile
> @@ -0,0 +1,19 @@
> +TESTMODS_DIR := $(realpath $(dir $(abspath $(lastword $(MAKEFILE_LIST)))))
> +KDIR ?= /lib/modules/$(shell uname -r)/build
> +
> +obj-m += test_klp_atomic_replace.o \
> + test_klp_callbacks_busy.o \
> + test_klp_callbacks_demo.o \
> + test_klp_callbacks_demo2.o \
> + test_klp_callbacks_mod.o \
> + test_klp_livepatch.o \
> + test_klp_state.o \
> + test_klp_state2.o \
> + test_klp_state3.o \
> + test_klp_shadow_vars.o
> +
> +modules:
> + $(Q)$(MAKE) -C $(KDIR) modules KBUILD_EXTMOD=$(TESTMODS_DIR)
> +
> +clean:
> + $(Q)$(MAKE) -C $(KDIR) clean KBUILD_EXTMOD=$(TESTMODS_DIR)
> diff --git a/lib/livepatch/test_klp_atomic_replace.c b/tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
> similarity index 100%
> rename from lib/livepatch/test_klp_atomic_replace.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_atomic_replace.c
> diff --git a/lib/livepatch/test_klp_callbacks_busy.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_busy.c
> similarity index 100%
> rename from lib/livepatch/test_klp_callbacks_busy.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_busy.c
> diff --git a/lib/livepatch/test_klp_callbacks_demo.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
> similarity index 100%
> rename from lib/livepatch/test_klp_callbacks_demo.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo.c
> diff --git a/lib/livepatch/test_klp_callbacks_demo2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
> similarity index 100%
> rename from lib/livepatch/test_klp_callbacks_demo2.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_demo2.c
> diff --git a/lib/livepatch/test_klp_callbacks_mod.c b/tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_mod.c
> similarity index 100%
> rename from lib/livepatch/test_klp_callbacks_mod.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_callbacks_mod.c
> diff --git a/lib/livepatch/test_klp_livepatch.c b/tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
> similarity index 100%
> rename from lib/livepatch/test_klp_livepatch.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_livepatch.c
> diff --git a/lib/livepatch/test_klp_shadow_vars.c b/tools/testing/selftests/livepatch/test_modules/test_klp_shadow_vars.c
> similarity index 100%
> rename from lib/livepatch/test_klp_shadow_vars.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_shadow_vars.c
> diff --git a/lib/livepatch/test_klp_state.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state.c
> similarity index 100%
> rename from lib/livepatch/test_klp_state.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_state.c
> diff --git a/lib/livepatch/test_klp_state2.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
> similarity index 100%
> rename from lib/livepatch/test_klp_state2.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_state2.c
> diff --git a/lib/livepatch/test_klp_state3.c b/tools/testing/selftests/livepatch/test_modules/test_klp_state3.c
> similarity index 100%
> rename from lib/livepatch/test_klp_state3.c
> rename to tools/testing/selftests/livepatch/test_modules/test_klp_state3.c
>
> --
> 2.42.0
>

2023-12-01 16:39:34

by Shuah Khan

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 12/1/23 06:13, Marcos Paulo de Souza wrote:
> On Thu, Nov 30, 2023 at 04:24:26PM -0700, Shuah Khan wrote:

>>
>> Missing module name? Is there a reason to not name this module?
>
> Can you please elaborate? This new module use the same MODULE_ macros used by
> the current livepatch selftests. What do you mean by module name?
>

Pre-commit checpatch script spdx check complained about the module name.
Please run it to see the message.

thanks,
-- Shuah

2023-12-05 12:53:12

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
> On 12/1/23 06:13, Marcos Paulo de Souza wrote:
> > On Thu, Nov 30, 2023 at 04:24:26PM -0700, Shuah Khan wrote:
>
> > >
> > > Missing module name? Is there a reason to not name this module?
> >
> > Can you please elaborate? This new module use the same MODULE_
> > macros used by
> > the current livepatch selftests. What do you mean by module name?
> >
>
> Pre-commit checpatch script spdx check complained about the module
> name.
> Please run it to see the message.

I've ran checkpatch on all the tree patches, and so far it complained
about MAINTANERS file needing to be updated (since we removed
lib/livepatch and it's mentioned on MAINTAINERS file):

$ ./scripts/checkpatch.pl 000*.patch
-----------------------------------------------------------
0001-kselftests-lib.mk-Add-TEST_GEN_MODS_DIR-variable.patch
-----------------------------------------------------------
total: 0 errors, 0 warnings, 68 lines checked

0001-kselftests-lib.mk-Add-TEST_GEN_MODS_DIR-variable.patch has no
obvious style problems and is ready for submission.
---------------------------------------------------------------
0002-livepatch-Move-tests-from-lib-livepatch-to-selftests.patch
---------------------------------------------------------------
WARNING: Prefer a maximum 75 chars per line (possible unwrapped commit
description?)
#17:
debug and rebuild the tests by running make on the selftests/livepatch
directory,

WARNING: added, moved or deleted file(s), does MAINTAINERS need
updating?
#82:
rename {lib/livepatch =>
tools/testing/selftests/livepatch/test_modules}/test_klp_atomic_replace
.c (100%)

total: 0 errors, 2 warnings, 519 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-
inplace.

0002-livepatch-Move-tests-from-lib-livepatch-to-selftests.patch has
style problems, please review.
---------------------------------------------------------------
0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch
---------------------------------------------------------------
WARNING: added, moved or deleted file(s), does MAINTAINERS need
updating?
#60:
new file mode 100755

total: 0 errors, 1 warnings, 237 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-
inplace.

0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
style problems, please review.

NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

I couldn't find any mention about "missing module name". Is your script
showing more warnings than these ones? Can you please share your
output?

I'll fix MAINTAINERS file but I'll wait until I understand what's
missing in your checkpatch script to resend the patchset.

Thanks,
Marcos

>
> thanks,
> -- Shuah
>

2023-12-05 15:39:40

by Shuah Khan

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 12/5/23 05:52, [email protected] wrote:
> On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:

> 0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
> style problems, please review.
>
> NOTE: If any of the errors are false positives, please report
> them to the maintainer, see CHECKPATCH in MAINTAINERS.
>
> I couldn't find any mention about "missing module name". Is your script
> showing more warnings than these ones? Can you please share your
> output?
>
> I'll fix MAINTAINERS file but I'll wait until I understand what's
> missing in your checkpatch script to resend the patchset.
>

Looks like it is coming a script - still my question stands on
whether or not you would need a module name for this module?

I am not too concerned about MAINTAINERS file warns.

I am assuming you will be sending a new version to address
Joe Lawrence's comments?

thanks,
-- Shuah

2023-12-06 14:39:40

by Miroslav Benes

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

Hi,

On Tue, 5 Dec 2023, Shuah Khan wrote:

> On 12/5/23 05:52, [email protected] wrote:
> > On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
>
> > 0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
> > style problems, please review.
> >
> > NOTE: If any of the errors are false positives, please report
> > them to the maintainer, see CHECKPATCH in MAINTAINERS.
> >
> > I couldn't find any mention about "missing module name". Is your script
> > showing more warnings than these ones? Can you please share your
> > output?
> >
> > I'll fix MAINTAINERS file but I'll wait until I understand what's
> > missing in your checkpatch script to resend the patchset.
> >
>
> Looks like it is coming a script - still my question stands on
> whether or not you would need a module name for this module?

I admit I am also clueless here. The module name is given in Makefile. In
this case in test_modules/Makefile. I do not know of anything else. There
is no MODULE_NAME macro. Could you elaborate, please?

Miroslav

2023-12-06 15:06:03

by Miroslav Benes

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On Fri, 1 Dec 2023, Joe Lawrence wrote:

> On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de Souza wrote:
> > The modules are being moved from lib/livepatch to
> > tools/testing/selftests/livepatch/test_modules.
> >
> > This code moving will allow writing more complex tests, like for example an
> > userspace C code that will call a livepatched kernel function.
> >
> > The modules are now built as out-of-tree
> > modules, but being part of the kernel source means they will be maintained.
> >
> > Another advantage of the code moving is to be able to easily change,
> > debug and rebuild the tests by running make on the selftests/livepatch directory,
> > which is not currently possible since the modules on lib/livepatch are
> > build and installed using the "modules" target.
> >
> > The current approach also keeps the ability to execute the tests manually by
> > executing the scripts inside selftests/livepatch directory, as it's currently
> > supported. If the modules are modified, they needed to be rebuilt before running
> > the scripts though.
> >
> > The modules are built before running the selftests when using the
> > kselftest invocations:
> >
> > make kselftest TARGETS=livepatch
> > or
> > make -C tools/testing/selftests/livepatch run_tests
> >
>
> Quick question:
>
> - We have been building with CONFIG_LIVEPATCH_TEST=m to generate the
> test modules at kernel build time
>
> - Our packaging filters out the selftest scripts and supporting modules
> from the general kernel RPM package into their subpackages
>
> - Tests are run as part of CKI or other manual tests by installing the
> pre-built packages from the previous step
>
>
> After this patch, we would need to add something like the following to
> our kernel build, before packaging:
>
> $ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
> ^^^^
>
> If this is the correct way to build the test modules for *this* tree and
> /lib/modules/$(shell uname -r)/build... it might be useful to document
> in the commit message as an alternative use case.

So if I understand it correctly, you would like to stick to pre-building
the modules (not in-tree but now after the kernel is build using the
proposed way), package them and then install everything on a system
running the respective kernel. A valid use case in my opinion.

My idea is to abandon this way completely, take the selftests and build
and run them on the system right away.

Both should be doable, hopefully, if we wire it all correctly... and
document it.

Miroslav

2023-12-07 15:20:35

by Joe Lawrence

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On 12/6/23 10:05, Miroslav Benes wrote:
> On Fri, 1 Dec 2023, Joe Lawrence wrote:
>
>> On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de Souza wrote:
>>> The modules are being moved from lib/livepatch to
>>> tools/testing/selftests/livepatch/test_modules.
>>>
>>> This code moving will allow writing more complex tests, like for example an
>>> userspace C code that will call a livepatched kernel function.
>>>
>>> The modules are now built as out-of-tree
>>> modules, but being part of the kernel source means they will be maintained.
>>>
>>> Another advantage of the code moving is to be able to easily change,
>>> debug and rebuild the tests by running make on the selftests/livepatch directory,
>>> which is not currently possible since the modules on lib/livepatch are
>>> build and installed using the "modules" target.
>>>
>>> The current approach also keeps the ability to execute the tests manually by
>>> executing the scripts inside selftests/livepatch directory, as it's currently
>>> supported. If the modules are modified, they needed to be rebuilt before running
>>> the scripts though.
>>>
>>> The modules are built before running the selftests when using the
>>> kselftest invocations:
>>>
>>> make kselftest TARGETS=livepatch
>>> or
>>> make -C tools/testing/selftests/livepatch run_tests
>>>
>>
>> Quick question:
>>
>> - We have been building with CONFIG_LIVEPATCH_TEST=m to generate the
>> test modules at kernel build time
>>
>> - Our packaging filters out the selftest scripts and supporting modules
>> from the general kernel RPM package into their subpackages
>>
>> - Tests are run as part of CKI or other manual tests by installing the
>> pre-built packages from the previous step
>>
>>
>> After this patch, we would need to add something like the following to
>> our kernel build, before packaging:
>>
>> $ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
>> ^^^^
>>
>> If this is the correct way to build the test modules for *this* tree and
>> /lib/modules/$(shell uname -r)/build... it might be useful to document
>> in the commit message as an alternative use case.
>
> So if I understand it correctly, you would like to stick to pre-building
> the modules (not in-tree but now after the kernel is build using the
> proposed way), package them and then install everything on a system
> running the respective kernel. A valid use case in my opinion.
>

That would accurate. If this use case can be supported, it wouldn't
require changes to our CKI / testing scripts, only the post-build
packaging bits.

> My idea is to abandon this way completely, take the selftests and build
> and run them on the system right away.
>
> Both should be doable, hopefully, if we wire it all correctly... and
> document it.
>
I can't think of why it shouldn't continue to work, even in a future
where newer livepatching selftests support older kernels. (We would
just have newer selftests sources backported to test older kernel sources.)

Are there any test cases which truly need to be build on-the-fly? Aside
from testing different toolchain pieces?

--
Joe

2023-12-07 19:20:21

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On Thu, 2023-12-07 at 10:20 -0500, Joe Lawrence wrote:
> On 12/6/23 10:05, Miroslav Benes wrote:
> > On Fri, 1 Dec 2023, Joe Lawrence wrote:
> >
> > > On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de Souza
> > > wrote:
> > > > The modules are being moved from lib/livepatch to
> > > > tools/testing/selftests/livepatch/test_modules.
> > > >
> > > > This code moving will allow writing more complex tests, like
> > > > for example an
> > > > userspace C code that will call a livepatched kernel function.
> > > >
> > > > The modules are now built as out-of-tree
> > > > modules, but being part of the kernel source means they will be
> > > > maintained.
> > > >
> > > > Another advantage of the code moving is to be able to easily
> > > > change,
> > > > debug and rebuild the tests by running make on the
> > > > selftests/livepatch directory,
> > > > which is not currently possible since the modules on
> > > > lib/livepatch are
> > > > build and installed using the "modules" target.
> > > >
> > > > The current approach also keeps the ability to execute the
> > > > tests manually by
> > > > executing the scripts inside selftests/livepatch directory, as
> > > > it's currently
> > > > supported. If the modules are modified, they needed to be
> > > > rebuilt before running
> > > > the scripts though.
> > > >
> > > > The modules are built before running the selftests when using
> > > > the
> > > > kselftest invocations:
> > > >
> > > > make kselftest TARGETS=livepatch
> > > > or
> > > > make -C tools/testing/selftests/livepatch run_tests
> > > >
> > >
> > > Quick question:
> > >
> > > - We have been building with CONFIG_LIVEPATCH_TEST=m to generate
> > > the
> > >   test modules at kernel build time
> > >
> > > - Our packaging filters out the selftest scripts and supporting
> > > modules
> > >   from the general kernel RPM package into their subpackages
> > >
> > > - Tests are run as part of CKI or other manual tests by
> > > installing the
> > >   pre-built packages from the previous step
> > >
> > >
> > > After this patch, we would need to add something like the
> > > following to
> > > our kernel build, before packaging:
> > >
> > >   $ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
> > >          ^^^^
> > >
> > > If this is the correct way to build the test modules for *this*
> > > tree and
> > > /lib/modules/$(shell uname -r)/build... it might be useful to
> > > document
> > > in the commit message as an alternative use case.

That's right:

$ make -C tools/testing/selftests/livepatch/

is indeed the way to build the tests without running them. KDIR will be
set to /lib/modules/$(shell uname -r)/build is empty.

Yes, I can definitely add documentation about it inside the
tools/testing/selftests/livepatch/README.

> >
> > So if I understand it correctly, you would like to stick to pre-
> > building
> > the modules (not in-tree but now after the kernel is build using
> > the
> > proposed way), package them and then install everything on a system
> > running the respective kernel. A valid use case in my opinion.
> >
>
> That would accurate.  If this use case can be supported, it wouldn't
> require changes to our CKI / testing scripts, only the post-build
> packaging bits.
>
> > My idea is to abandon this way completely, take the selftests and
> > build
> > and run them on the system right away.
> >
> > Both should be doable, hopefully, if we wire it all correctly...
> > and
> > document it.
> >
> I can't think of why it shouldn't continue to work, even in a future
> where newer livepatching selftests support older kernels.  (We would
> just have newer selftests sources backported to test older kernel
> sources.)
>
> Are there any test cases which truly need to be build on-the-fly? 
> Aside
> from testing different toolchain pieces?

We would like to use the same selftests to trigger testing on different
kernels (adjusting it when necessary as you stated), without having to
rebuild the kernel. Miroslav may have other ideias about it too, IIRC.

>

2023-12-08 08:06:40

by Miroslav Benes

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

> > My idea is to abandon this way completely, take the selftests and build
> > and run them on the system right away.
> >
> > Both should be doable, hopefully, if we wire it all correctly... and
> > document it.
> >
> I can't think of why it shouldn't continue to work, even in a future
> where newer livepatching selftests support older kernels. (We would
> just have newer selftests sources backported to test older kernel sources.)
>
> Are there any test cases which truly need to be build on-the-fly? Aside
> from testing different toolchain pieces?

https://github.com/SUSE/qa_test_klp is what we would like to migrate to
selftests to have just one place for all tests.

There is basically just one live patch template and one supporting kernel
module template which is livepatched. The final result is driven by a set
of macros and function parameters. In some cases more modules are compiled
as parts of a test in a loop.

However, I do not think there is anything which truly needs to be built
on-the-fly in the end. Everything can be worked around. Templates may be
abandoned and we would have a live patch and a module(s) per test. Some
tests are probably not worth it and may be removed. So it is a question of
convenience and maintainability. When we, for example, simplified API and
klp_register_patch() was removed, only one place needed to be amended.
Also, the current state in lib/livepatch/ could be simplified with the
proposed infrastructure as some files could be merged together.

Miroslav

2023-12-08 12:43:48

by Petr Mladek

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On Fri 2023-12-08 09:06:30, Miroslav Benes wrote:
> > > My idea is to abandon this way completely, take the selftests and build
> > > and run them on the system right away.
> > >
> > > Both should be doable, hopefully, if we wire it all correctly... and
> > > document it.
> > >
> > I can't think of why it shouldn't continue to work, even in a future
> > where newer livepatching selftests support older kernels. (We would
> > just have newer selftests sources backported to test older kernel sources.)
> >
> > Are there any test cases which truly need to be build on-the-fly? Aside
> > from testing different toolchain pieces?
>
> https://github.com/SUSE/qa_test_klp is what we would like to migrate to
> selftests to have just one place for all tests.
>
> There is basically just one live patch template and one supporting kernel
> module template which is livepatched. The final result is driven by a set
> of macros and function parameters. In some cases more modules are compiled
> as parts of a test in a loop.
>
> However, I do not think there is anything which truly needs to be built
> on-the-fly in the end. Everything can be worked around. Templates may be
> abandoned and we would have a live patch and a module(s) per test. Some
> tests are probably not worth it and may be removed. So it is a question of
> convenience and maintainability. When we, for example, simplified API and
> klp_register_patch() was removed, only one place needed to be amended.
> Also, the current state in lib/livepatch/ could be simplified with the
> proposed infrastructure as some files could be merged together.

In the patchset reworking livepatch states, I solved this problem
by including the same sources in another module source, like:

$> cat lib/livepatch/test_klp_speaker_livepatch2.c
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2023 SUSE

/* Same livepatch with the same features. */
#include "test_klp_speaker_livepatch.c"

=========

$> cat lib/livepatch/test_klp_speaker2.c
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2023 SUSE

/* Use versioned function name for livepatched functions */
#define _VER_NAME(name) name ## 2

/* Same module with the same features. */
#include "test_klp_speaker.c"

==========

And the behavior was changed by module parameters. The test
lookes like:

$> cat tools/testing/selftests/livepatch/test-modules.sh
[...]
start_test "multiple target modules"

load_mod $MOD_TARGET
read_module_param $MOD_TARGET welcome

load_lp $MOD_LIVEPATCH add_applause=1
read_module_param $MOD_TARGET welcome

load_mod $MOD_TARGET2
read_module_param $MOD_TARGET2 welcome

unload_mod $MOD_TARGET2
disable_lp $MOD_LIVEPATCH
read_module_param $MOD_TARGET welcome

unload_lp $MOD_LIVEPATCH
unload_mod $MOD_TARGET

===========

It is a kind of hack. But it would allow to build and package the
test modules. It has several advantages:

+ Less modules are needed. The behavior is modified by
the parameters.

+ The separate parameters are easier to parse in compare
with embedding the behavior into the module name.

+ Build problems would be solved before the packages
reach QA department

+ The package would have lightweight dependencies.

+ Running the tests would be faster.



Regarding disadvantages:

+ The source included in all the other variants would be more
complex.

But the same would happen when building the modules during
the tests. It would also require a more complicated template
and an extra script generating the particular module sources.


I personally prefer the solution with "#include" because it has
all the mentioned advantages. The "#include" is a hack but it is
needed only when we need more modules with all the features.

Best Regards,
Petr

2023-12-11 21:53:27

by Shuah Khan

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 12/6/23 07:39, Miroslav Benes wrote:
> Hi,
>
> On Tue, 5 Dec 2023, Shuah Khan wrote:
>
>> On 12/5/23 05:52, [email protected] wrote:
>>> On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
>>
>>> 0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
>>> style problems, please review.
>>>
>>> NOTE: If any of the errors are false positives, please report
>>> them to the maintainer, see CHECKPATCH in MAINTAINERS.
>>>
>>> I couldn't find any mention about "missing module name". Is your script
>>> showing more warnings than these ones? Can you please share your
>>> output?
>>>
>>> I'll fix MAINTAINERS file but I'll wait until I understand what's
>>> missing in your checkpatch script to resend the patchset.
>>>
>>
>> Looks like it is coming a script - still my question stands on
>> whether or not you would need a module name for this module?
>
> I admit I am also clueless here. The module name is given in Makefile. In
> this case in test_modules/Makefile. I do not know of anything else. There
> is no MODULE_NAME macro. Could you elaborate, please?
>

I see that now.

thanks,
-- Shuah

2023-12-11 21:56:30

by Shuah Khan

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On 12/7/23 12:19, [email protected] wrote:
> On Thu, 2023-12-07 at 10:20 -0500, Joe Lawrence wrote:
>> On 12/6/23 10:05, Miroslav Benes wrote:
>>> On Fri, 1 Dec 2023, Joe Lawrence wrote:
>>>
>>>> On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de Souza
>>>> wrote:
>>>>> The modules are being moved from lib/livepatch to
>>>>> tools/testing/selftests/livepatch/test_modules.
>>>>>
>>>>> This code moving will allow writing more complex tests, like
>>>>> for example an
>>>>> userspace C code that will call a livepatched kernel function.
>>>>>
>>>>> The modules are now built as out-of-tree
>>>>> modules, but being part of the kernel source means they will be
>>>>> maintained.
>>>>>
>>>>> Another advantage of the code moving is to be able to easily
>>>>> change,
>>>>> debug and rebuild the tests by running make on the
>>>>> selftests/livepatch directory,
>>>>> which is not currently possible since the modules on
>>>>> lib/livepatch are
>>>>> build and installed using the "modules" target.
>>>>>
>>>>> The current approach also keeps the ability to execute the
>>>>> tests manually by
>>>>> executing the scripts inside selftests/livepatch directory, as
>>>>> it's currently
>>>>> supported. If the modules are modified, they needed to be
>>>>> rebuilt before running
>>>>> the scripts though.
>>>>>
>>>>> The modules are built before running the selftests when using
>>>>> the
>>>>> kselftest invocations:
>>>>>
>>>>> make kselftest TARGETS=livepatch
>>>>> or
>>>>> make -C tools/testing/selftests/livepatch run_tests
>>>>>
>>>>
>>>> Quick question:
>>>>
>>>> - We have been building with CONFIG_LIVEPATCH_TEST=m to generate
>>>> the
>>>>   test modules at kernel build time
>>>>
>>>> - Our packaging filters out the selftest scripts and supporting
>>>> modules
>>>>   from the general kernel RPM package into their subpackages
>>>>
>>>> - Tests are run as part of CKI or other manual tests by
>>>> installing the
>>>>   pre-built packages from the previous step
>>>>
>>>>
>>>> After this patch, we would need to add something like the
>>>> following to
>>>> our kernel build, before packaging:
>>>>
>>>>   $ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
>>>>          ^^^^
>>>>
>>>> If this is the correct way to build the test modules for *this*
>>>> tree and
>>>> /lib/modules/$(shell uname -r)/build... it might be useful to
>>>> document
>>>> in the commit message as an alternative use case.
>
> That's right:
>
> $ make -C tools/testing/selftests/livepatch/
>
> is indeed the way to build the tests without running them. KDIR will be
> set to /lib/modules/$(shell uname -r)/build is empty.
>
> Yes, I can definitely add documentation about it inside the
> tools/testing/selftests/livepatch/README.
>

How does the default kselftest run work with these changes?

make ksefltest - does this still work as it did before this change?

thanks,
-- Shuah

2023-12-12 02:01:28

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 2/3] livepatch: Move tests from lib/livepatch to selftests/livepatch

On Mon, 2023-12-11 at 14:56 -0700, Shuah Khan wrote:
> On 12/7/23 12:19, [email protected] wrote:
> > On Thu, 2023-12-07 at 10:20 -0500, Joe Lawrence wrote:
> > > On 12/6/23 10:05, Miroslav Benes wrote:
> > > > On Fri, 1 Dec 2023, Joe Lawrence wrote:
> > > >
> > > > > On Tue, Oct 31, 2023 at 06:10:52PM -0300, Marcos Paulo de
> > > > > Souza
> > > > > wrote:
> > > > > > The modules are being moved from lib/livepatch to
> > > > > > tools/testing/selftests/livepatch/test_modules.
> > > > > >
> > > > > > This code moving will allow writing more complex tests,
> > > > > > like
> > > > > > for example an
> > > > > > userspace C code that will call a livepatched kernel
> > > > > > function.
> > > > > >
> > > > > > The modules are now built as out-of-tree
> > > > > > modules, but being part of the kernel source means they
> > > > > > will be
> > > > > > maintained.
> > > > > >
> > > > > > Another advantage of the code moving is to be able to
> > > > > > easily
> > > > > > change,
> > > > > > debug and rebuild the tests by running make on the
> > > > > > selftests/livepatch directory,
> > > > > > which is not currently possible since the modules on
> > > > > > lib/livepatch are
> > > > > > build and installed using the "modules" target.
> > > > > >
> > > > > > The current approach also keeps the ability to execute the
> > > > > > tests manually by
> > > > > > executing the scripts inside selftests/livepatch directory,
> > > > > > as
> > > > > > it's currently
> > > > > > supported. If the modules are modified, they needed to be
> > > > > > rebuilt before running
> > > > > > the scripts though.
> > > > > >
> > > > > > The modules are built before running the selftests when
> > > > > > using
> > > > > > the
> > > > > > kselftest invocations:
> > > > > >
> > > > > > make kselftest TARGETS=livepatch
> > > > > > or
> > > > > > make -C tools/testing/selftests/livepatch
> > > > > > run_tests
> > > > > >
> > > > >
> > > > > Quick question:
> > > > >
> > > > > - We have been building with CONFIG_LIVEPATCH_TEST=m to
> > > > > generate
> > > > > the
> > > > >    test modules at kernel build time
> > > > >
> > > > > - Our packaging filters out the selftest scripts and
> > > > > supporting
> > > > > modules
> > > > >    from the general kernel RPM package into their subpackages
> > > > >
> > > > > - Tests are run as part of CKI or other manual tests by
> > > > > installing the
> > > > >    pre-built packages from the previous step
> > > > >
> > > > >
> > > > > After this patch, we would need to add something like the
> > > > > following to
> > > > > our kernel build, before packaging:
> > > > >
> > > > >    $ make KDIR=$(pwd) -C tools/testing/selftests/livepatch/
> > > > >           ^^^^
> > > > >
> > > > > If this is the correct way to build the test modules for
> > > > > *this*
> > > > > tree and
> > > > > /lib/modules/$(shell uname -r)/build... it might be useful to
> > > > > document
> > > > > in the commit message as an alternative use case.
> >
> > That's right:
> >
> > $ make -C tools/testing/selftests/livepatch/
> >
> > is indeed the way to build the tests without running them. KDIR
> > will be
> > set to  /lib/modules/$(shell uname -r)/build is empty.
> >
> > Yes, I can definitely add documentation about it inside the
> > tools/testing/selftests/livepatch/README.
> >
>
> How does the default kselftest run work with these changes?
>
> make ksefltest - does this still work as it did before this change?

Yes,

make kselftest TARGETS=livepatch

works the same as before. As well the

make -C tools/testing/selftests/livepatch run_tests

Both ways work as before.
>
> thanks,
> -- Shuah
>

2023-12-15 20:36:46

by Joe Lawrence

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 12/11/23 16:53, Shuah Khan wrote:
> On 12/6/23 07:39, Miroslav Benes wrote:
>> Hi,
>>
>> On Tue, 5 Dec 2023, Shuah Khan wrote:
>>
>>> On 12/5/23 05:52, [email protected] wrote:
>>>> On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
>>>
>>>> 0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
>>>> style problems, please review.
>>>>
>>>> NOTE: If any of the errors are false positives, please report
>>>>         them to the maintainer, see CHECKPATCH in MAINTAINERS.
>>>>
>>>> I couldn't find any mention about "missing module name". Is your script
>>>> showing more warnings than these ones? Can you please share your
>>>> output?
>>>>
>>>> I'll fix MAINTAINERS file but I'll wait until I understand what's
>>>> missing in your checkpatch script to resend the patchset.
>>>>
>>>
>>> Looks like it is coming a script - still my question stands on
>>> whether or not you would need a module name for this module?
>>
>> I admit I am also clueless here. The module name is given in Makefile. In
>> this case in test_modules/Makefile. I do not know of anything else. There
>> is no MODULE_NAME macro. Could you elaborate, please?
>>
>
> I see that now.
>

Hi Shuah,

In the other replies to this thread, Marcos noted that he would add some
text to the commit / documentation on running and building the selftests
directly in the kernel tree (that would get my Ack) ... is there
anything else to be updated for a hopefully final v4 (for your Ack)?

Thanks,
--
Joe

2023-12-18 20:48:10

by Shuah Khan

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On 12/15/23 13:36, Joe Lawrence wrote:
> On 12/11/23 16:53, Shuah Khan wrote:
>> On 12/6/23 07:39, Miroslav Benes wrote:
>>> Hi,
>>>
>>> On Tue, 5 Dec 2023, Shuah Khan wrote:
>>>
>>>> On 12/5/23 05:52, [email protected] wrote:
>>>>> On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
>>>>
>>>>> 0003-selftests-livepatch-Test-livepatching-a-heavily-call.patch has
>>>>> style problems, please review.
>>>>>
>>>>> NOTE: If any of the errors are false positives, please report
>>>>>         them to the maintainer, see CHECKPATCH in MAINTAINERS.
>>>>>
>>>>> I couldn't find any mention about "missing module name". Is your script
>>>>> showing more warnings than these ones? Can you please share your
>>>>> output?
>>>>>
>>>>> I'll fix MAINTAINERS file but I'll wait until I understand what's
>>>>> missing in your checkpatch script to resend the patchset.
>>>>>
>>>>
>>>> Looks like it is coming a script - still my question stands on
>>>> whether or not you would need a module name for this module?
>>>
>>> I admit I am also clueless here. The module name is given in Makefile. In
>>> this case in test_modules/Makefile. I do not know of anything else. There
>>> is no MODULE_NAME macro. Could you elaborate, please?
>>>
>>
>> I see that now.
>>
>
> Hi Shuah,
>
> In the other replies to this thread, Marcos noted that he would add some
> text to the commit / documentation on running and building the selftests
> directly in the kernel tree (that would get my Ack) ... is there
> anything else to be updated for a hopefully final v4 (for your Ack)?
>


I am waiting for v4 with your comments are addressed. I can take
this through kselftest tree.

thanks,
-- Shuah

2023-12-20 11:34:01

by Marcos Paulo de Souza

Subject: Re: [PATCH v3 3/3] selftests: livepatch: Test livepatching a heavily called syscall

On Mon, 2023-12-18 at 13:47 -0700, Shuah Khan wrote:
> On 12/15/23 13:36, Joe Lawrence wrote:
> > On 12/11/23 16:53, Shuah Khan wrote:
> > > On 12/6/23 07:39, Miroslav Benes wrote:
> > > > Hi,
> > > >
> > > > On Tue, 5 Dec 2023, Shuah Khan wrote:
> > > >
> > > > > On 12/5/23 05:52, [email protected] wrote:
> > > > > > On Fri, 2023-12-01 at 16:38 +0000, Shuah Khan wrote:
> > > > >
> > > > > > 0003-selftests-livepatch-Test-livepatching-a-heavily-
> > > > > > call.patch has
> > > > > > style problems, please review.
> > > > > >
> > > > > > NOTE: If any of the errors are false positives, please
> > > > > > report
> > > > > >          them to the maintainer, see CHECKPATCH in
> > > > > > MAINTAINERS.
> > > > > >
> > > > > > I couldn't find any mention about "missing module name". Is
> > > > > > your script
> > > > > > showing more warnings than these ones? Can you please share
> > > > > > your
> > > > > > output?
> > > > > >
> > > > > > I'll fix MAINTAINERS file but I'll wait until I understand
> > > > > > what's
> > > > > > missing in your checkpatch script to resend the patchset.
> > > > > >
> > > > >
> > > > > Looks like it is coming a script - still my question stands
> > > > > on
> > > > > whether or not you would need a module name for this module?
> > > >
> > > > I admit I am also clueless here. The module name is given in
> > > > Makefile. In
> > > > this case in test_modules/Makefile. I do not know of anything
> > > > else. There
> > > > is no MODULE_NAME macro. Could you elaborate, please?
> > > >
> > >
> > > I see that now.
> > >
> >
> > Hi Shuah,
> >
> > In the other replies to this thread, Marcos noted that he would add
> > some
> > text to the commit / documentation on running and building the
> > selftests
> > directly in the kernel tree (that would get my Ack) ... is there
> > anything else to be updated for a hopefully final v4 (for your
> > Ack)?
> >
>
>
> I am waiting for v4 with your comments are addressed. I can take
> this through kselftest tree.

Ok. I'm already preparing the v4. The plan is to send in the next few
days.

Thanks,
Marcos

>
> thanks,
> -- Shuah
>