On Wed, Jul 15, 2020 at 11:11 AM Vitor Massaru Iha vitor@massaru.org wrote:
Currently, KUnit does not allow the use of tests as a module. This prevents the implementation of tests that require userspace.
If this is what I think it is, thanks! I'll hopefully get a chance to play with it over the next few days.
Can we clarify what this means: the current description is a little misleading, as KUnit tests can already be built and run as modules, and "tests that require userspace" is a bit broad.
As I understand it, this patchset does three things: - Let kunit_tool install modules to a root filesystem and boot UML with that filesystem. - Have tests inherit the mm of the process that started them, which (if the test is in a module), provides a user-space memory context so that copy_{from,to}_user() works. - Port the test_user_copy.c tests to KUnit, using this new feature.
A few comments from my quick glance over it: - The rootfs support is useful: I'm curious how it'll interact with non-UML architectures in [1]. It'd be nice for this to be extensible and to not explicitly state UML where possible. - The inheriting of the mm stuff still means that copy_{from,to}_user() will only work if loaded as a module. This really needs to be documented. (Ideally, we'd find a way of having this work even for built-in tests, but I don't have any real ideas as to how that could be done). - It'd be nice to split the test_user_copy.c test port into a separate commit. In fact, it may make sense to also split the kunit_tool changes and the mm changes into separate series, as they're both quite useful independently.
Cheers, -- David
This patchset makes this possible by introducing the use of the root filesystem in KUnit. And it allows the use of tests that can be compiled as a module
Vitor Massaru Iha (3): kunit: tool: Add support root filesystem in kunit-tool lib: Allows to borrow mm in userspace on KUnit lib: Convert test_user_copy to KUnit test
include/kunit/test.h | 1 + lib/Kconfig.debug | 17 ++ lib/Makefile | 2 +- lib/kunit/try-catch.c | 15 +- lib/{test_user_copy.c => user_copy_kunit.c} | 196 +++++++++----------- tools/testing/kunit/kunit.py | 37 +++- tools/testing/kunit/kunit_kernel.py | 105 +++++++++-- 7 files changed, 238 insertions(+), 135 deletions(-) rename lib/{test_user_copy.c => user_copy_kunit.c} (55%)
base-commit: 725aca9585956676687c4cb803e88f770b0df2b2 prerequisite-patch-id: 582b6d9d28ce4b71628890ec832df6522ca68de0 -- 2.26.2