On Tue, Mar 05, 2024 at 10:40:29AM -0800, Guenter Roeck wrote: > [...] > warning = (bug->flags & BUGFLAG_WARNING) != 0; > once = (bug->flags & BUGFLAG_ONCE) != 0; > done = (bug->flags & BUGFLAG_DONE) != 0; > > + if (warning && IS_SUPPRESSED_WARNING(function)) > + return BUG_TRAP_TYPE_WARN; > + I had to re-read __report_bug() more carefully, but yes, this works -- it's basically leaving early, like "once" does. This looks like a reasonable approach! Something very similar to this is checking that a warning happens. i.e. you talk about drm selftests checking function return values, but I've got a bunch of tests (LKDTM) that live outside of KUnit because I haven't had a clean way to check for specific warnings/bugs. I feel like future changes built on top of this series could add counters or something that KUnit could examine. E.g. I did this manually for some fortify tests: https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/commit/?h=for-next/hardening&id=4ce615e798a752d4431fcc52960478906dec2f0e -Kees -- Kees Cook