On Fri, Mar 20, 2026 at 12:06:52AM +0800, Chunyu Hu wrote: > When thp is not available, just skip the collape tests to avoid the false > negative. > > Without the change, run with a thp disabled kernel: > ./run_vmtests.sh -t madv_guard -n 1 > <snip/> > # RUN guard_regions.anon.collapse ... > # guard-regions.c:2217:collapse:Expected madvise(ptr, size, > MADV_NOHUGEPAGE) (-1) == 0 (0) > # collapse: Test terminated by assertion > # FAIL guard_regions.anon.collapse > not ok 2 guard_regions.anon.collapse > <snip/> > # RUN guard_regions.shmem.collapse ... > # guard-regions.c:2217:collapse:Expected madvise(ptr, size, > MADV_NOHUGEPAGE) (-1) == 0 (0) > # collapse: Test terminated by assertion > # FAIL guard_regions.shmem.collapse > not ok 32 guard_regions.shmem.collapse > <snip/> > # RUN guard_regions.file.collapse ... > # guard-regions.c:2217:collapse:Expected madvise(ptr, size, > MADV_NOHUGEPAGE) (-1) == 0 (0) > # collapse: Test terminated by assertion > # FAIL guard_regions.file.collapse > not ok 62 guard_regions.file.collapse > <snip/> > # FAILED: 87 / 90 tests passed. > # 17 skipped test(s) detected. Consider enabling relevant config options to > improve coverage. > # Totals: pass:70 fail:3 xfail:0 xpass:0 skip:17 error:0 > > With this change, run with thp disabled kernel: > ./run_vmtests.sh -t madv_guard -n 1 > <snip/> > # RUN guard_regions.anon.collapse ... > # SKIP Transparent Hugepages not available > # OK guard_regions.anon.collapse > ok 2 guard_regions.anon.collapse # SKIP Transparent Hugepages not available > <snip/> > # RUN guard_regions.file.collapse ... > # SKIP Transparent Hugepages not available > # OK guard_regions.file.collapse > ok 62 guard_regions.file.collapse # SKIP Transparent Hugepages not available > <snip/> > # RUN guard_regions.shmem.collapse ... > # SKIP Transparent Hugepages not available > # OK guard_regions.shmem.collapse > ok 32 guard_regions.shmem.collapse # SKIP Transparent Hugepages not > available > <snip/> > # PASSED: 90 / 90 tests passed. > # 20 skipped test(s) detected. Consider enabling relevant config options to > improve coverage. > # Totals: pass:70 fail:0 xfail:0 xpass:0 skip:20 error:0 > > CC: Li Wang <[email protected]> > Signed-off-by: Chunyu Hu <[email protected]>
Acked-by: Mike Rapoport (Microsoft) <[email protected]> > --- > Changes in v4: > - use thp_available instead of thp_is_enabled() as when thp is set to > never, madvise(MADV_COLLAPSE) will still succeed by design. So a > failure in madvise(MADV_COLLAPSE) on guard region will verify guard > region denies it. This is suggested from AI. > - removed the 'Reviewed-by' and 'Acked-by' as the code changes. Sorry for > that but it seems the changes is a little huge? (1 out of 2 lines).. > Changes in v3: > - commit message: update the log snippet with where the fail happens and > add the '-n1' to the command. > - fix the 'false positive' to 'false negative' > - add reviwed by from Mike > Changes in v2: > - add reviewed by from Zi and Lorenzo > - add acked-by from David > --- > tools/testing/selftests/mm/guard-regions.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/tools/testing/selftests/mm/guard-regions.c > b/tools/testing/selftests/mm/guard-regions.c > index dbd21d66d383..48e8b1539be3 100644 > --- a/tools/testing/selftests/mm/guard-regions.c > +++ b/tools/testing/selftests/mm/guard-regions.c > @@ -21,6 +21,7 @@ > #include <sys/uio.h> > #include <unistd.h> > #include "vm_util.h" > +#include "thp_settings.h" > > #include "../pidfd/pidfd.h" > > @@ -2195,6 +2196,9 @@ TEST_F(guard_regions, collapse) > char *ptr; > int i; > > + if (!thp_available()) > + SKIP(return, "Transparent Hugepages not available\n"); > + > /* Need file to be correct size for tests for non-anon. */ > if (variant->backing != ANON_BACKED) > ASSERT_EQ(ftruncate(self->fd, size), 0); > > base-commit: 8a30aeb0d1b4e4aaf7f7bae72f20f2ae75385ccb > -- > 2.53.0 > -- Sincerely yours, Mike.
