Re: [PATCH RESEND v4 1/3] kselftests: lib.mk: Add TEST_GEN_MODS_DIR variable

Shuah Khan
2024-01-03T22:09:22Z

On 1/2/24 15:31, Joe Lawrence wrote:
> On Wed, Dec 20, 2023 at 01:53:12PM -0300, Marcos Paulo de Souza wrote:
>> 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 <mpdesouza@suse.com>
>> ---
>> 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 ab376b316c36..7f3582a67318 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)
>
> Hi Marcos,
>
> Sorry for the late reply on this, but I'm reviewing this version by
> trying to retrofit it into our selftest packaging (pre-build the test
> module .ko's and stash those into an rpm rather than building on the
> test host).
>
> Since $TEST_GEN_MODS_DIR is treated as a directory, I found that the
> selftest install target copies a bunch of intermediate object and kbuild
> files:
>
> $ mkdir /tmp/test-install
> $ make KDIR=$(pwd) INSTALL_PATH=/tmp/test-install TARGETS=livepatch \
> -C tools/testing/selftests/ install
>
> [ ... builds livepatch selftests ... ]
>
> the rsync in question:
>
> rsync -a --copy-unsafe-links /home/jolawren/src/kernel/tools/testing/selftests/livepatch/test_modules /tmp/test-install/livepatch/
> ...
>
> and then looking at the destination:
>
> $ tree -a /tmp/test-install/
> /tmp/test-install/
> ├── kselftest
> │   ├── module.sh
> │   ├── prefix.pl
> │   └── runner.sh
> ├── kselftest-list.txt
> ├── livepatch
> │   ├── config
> │   ├── functions.sh
> │   ├── settings
> │   ├── test-callbacks.sh
> │   ├── test-ftrace.sh
> │   ├── test_klp-call_getpid
> │   ├── test-livepatch.sh
> │   ├── test_modules
> │   │   ├── Makefile
> │   │   ├── modules.order
> │   │   ├── .modules.order.cmd
> │   │   ├── Module.symvers
> │   │   ├── .Module.symvers.cmd
> │   │   ├── test_klp_atomic_replace.c
> │   │   ├── test_klp_atomic_replace.ko
> │   │   ├── .test_klp_atomic_replace.ko.cmd
> │   │   ├── test_klp_atomic_replace.mod
> │   │   ├── test_klp_atomic_replace.mod.c
> │   │   ├── .test_klp_atomic_replace.mod.cmd
> │   │   ├── test_klp_atomic_replace.mod.o
> │   │   ├── .test_klp_atomic_replace.mod.o.cmd
> │   │   ├── test_klp_atomic_replace.o
> │   │   ├── .test_klp_atomic_replace.o.cmd
> ...
>
> On the other hand, variables like $TEST_GEN_FILES specify individual
> files, so only final binaries like test_klp-call_getpid (and not
> test_klp-call_getpid.c) are copied to $INSTALL_PATH.

Thank you Joe for finding this problem.

Copying source files and object files doesn't sound right. This isn't
how the ksleftest installs work. Let's fix this.

thanks,
--Shuah