Den tirs. 25. aug. 2026 kl. 13.00 skrev David Gow <[email protected]>:
>
> Le 24/08/2026 à 21:32, Malte Wechter a écrit :
> > add pre-defined KUnit test suite and test case that asserts both
> > `debug_locks` and `TAINT_WARN` prior to running any (user) KUnit tests.
> > This asserts integrity before tests are run.
> >
> > Signed-off-by: Malte Wechter <[email protected]>
> > ---
>
> I'm not quite as convinced by this as I am by the first patch. While
> ensuring the state of the system is good before tests are run is useful,
> this does seem a bit heavy-handed in some respects.
>
> This could probably use a more detailed description, particularly
> describing why such a test is useful, and why it would need to be
> implemented in a special way.
>
> And I do think the implementation here is a bit _too_ special-cased. One
> other possibility would be to prepend this suite using
> kunit_merge_suite_sets(), so we don't need to have any special handling
> of (e.g.) the test count. This could also allow this special suite to be
> filtered out (which has both advantages and disadvantages).
>
> It might also be nice to have this configurable independently from the
> other checks, and maybe at runtime (via a KUnit module / command-line
> parameter), particularly if this can't be filtered on. And, as before,
> this definitely needs to be documented. People need to know how to
> enable it, and where all of these extra results from tests they didn't
> enable came from.
>
> Thoughts?
I get your point, the purpose of this special test suite is to assert
that the kernel is in a "fine" state before any unit tests are run. If
this
check is left out the false positives could occur if the system is in
a bad state before the tests are run.
The reason that the case was handled differently compared to other was
because this assertion _must_ be run before any other tests,
and when kunit_merge_suite_sets() is called from kunit_run_all_tests()
it also filters the test suites, which would not give any guarentee
that this
special suite gets run first.
I do agree that this initial way is maybe a bit coarse, and i will see
if i can find a better fit for this assertion. But i dont want to
leave it out.
>
> Cheers,
> -- David
>
> > lib/kunit/executor.c | 8 +++++++-
> > lib/kunit/test.c | 30 ++++++++++++++++++++++++++++++
> > 2 files changed, 37 insertions(+), 1 deletion(-)
> >
> > diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
> > index b0f8a41d61d36..0db67fe7f09f9 100644
> > --- a/lib/kunit/executor.c
> > +++ b/lib/kunit/executor.c
> > @@ -290,9 +290,15 @@ void kunit_exec_run_tests(struct kunit_suite_set
> > *suite_set, bool builtin)
> > size_t num_suites = suite_set->end - suite_set->start;
> > bool autorun = kunit_autorun();
> >
> > + #ifdef CONFIG_KUNIT_EXTRA_ASSERTS
>
> Nit: Let's not indent the #ifdefs.
>
> > + size_t num_suites_plus_extra = num_suites+1;
> > + #else
> > + size_t num_suites_plus_extra = num_suites;
> > + #endif
> > +
>
> I'm not particularly happy with this way of adding an extra suite.
>
> > if (autorun && (builtin || num_suites)) {
> > pr_info("KTAP version 1\n");
> > - pr_info("1..%zu\n", num_suites);
> > + pr_info("1..%zu\n", num_suites_plus_extra);
> > }
> >
> > __kunit_test_suites_init(suite_set->start, num_suites, autorun);
> > diff --git a/lib/kunit/test.c b/lib/kunit/test.c
> > index 99773e000e1b7..e64c6d1575280 100644
> > --- a/lib/kunit/test.c
> > +++ b/lib/kunit/test.c
> > @@ -835,6 +835,30 @@ bool kunit_enabled(void)
> > return enable_param;
> > }
> >
> > +#ifdef CONFIG_KUNIT_EXTRA_ASSERTS
> > +#define DEBUG_LOCKS_OK 1
> > +#define TAINT_WARN_OK 0
>
> Not totally sold on these #defines: I think I'd prefer to just have the
> literal 1/0.
>
> > +
> > +static void pre_kunit_assert(struct kunit *test)
> > +{
> > + KUNIT_EXPECT_EQ_MSG(test, debug_locks, DEBUG_LOCKS_OK,
> > + "debug_locks are off before any test ran");
> > + KUNIT_EXPECT_EQ_MSG(test, test_taint(TAINT_WARN), TAINT_WARN_OK,
> > + "kernel already TAINT_WARN tainted before any test ran");
> > +}
>
> If we are going to generate a special suite, let's have the taint and
> lockdep checks as separate tests.
>
> This would also make it easier to have them be configurable separately.
>
> > +
> > +static struct kunit_case pre_kunit_assert_cases[] = {
> > + KUNIT_CASE(pre_kunit_assert),
> > + {}
> > +};
> > +
> > +static struct kunit_suite pre_kunit_assert_clean_state_suite = {
> > + .name = "pre_kunit_extra_asserts",
>
> I think we could probably find a better name for this.
> "initial_system_state" or similar might be better?
>
> > + .test_cases = pre_kunit_assert_cases,
> > +};
> > +
> > +#endif /* CONFIG_RUST_KUNIT_EXTRA_ASSERTS */
> > +
> > int __kunit_test_suites_init(struct kunit_suite * const * const suites,
> > int num_suites,
> > bool run_tests)
> > {
> > @@ -857,6 +881,12 @@ int __kunit_test_suites_init(struct kunit_suite *
> > const * const suites, int num_
> > }
> > static_branch_inc(&kunit_running);
> >
> > + #ifdef CONFIG_KUNIT_EXTRA_ASSERTS
> > + kunit_init_suite(&pre_kunit_assert_clean_state_suite);
> > + if (run_tests)
> > + kunit_run_tests(&pre_kunit_assert_clean_state_suite);
> > + #endif
> > +
> > for (i = 0; i < num_suites; i++) {
> > kunit_init_suite(suites[i]);
> > if (run_tests)
> >
>
Best regards,
Malte :)
