On Mon, 27 Jul 2026 10:52:18 +0100 Muhammad Usama Anjum <[email protected]> wrote:
> The hole_punch case verifies that guard regions survive MADV_REMOVE and > that the backing range is punched out. MADV_REMOVE delegates the hole > punch to the backing filesystem, which may reject the operation with > EOPNOTSUPP. > > That result means the test cannot establish the state whose guard > semantics it intends to validate. Treating the missing filesystem > capability as a guard-region failure creates a false regression. > > Unmap the range and skip only when MADV_REMOVE fails with EOPNOTSUPP. > Preserve the assertion for all other errors so failures on supported > configurations remain visible. > > Tested-by: Sarthak Sharma <[email protected]> > Signed-off-by: Muhammad Usama Anjum <[email protected]> > --- > tools/testing/selftests/mm/guard-regions.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/tools/testing/selftests/mm/guard-regions.c > b/tools/testing/selftests/mm/guard-regions.c > index b21df3040b1c7..5c8ec3ca75d7d 100644 > --- a/tools/testing/selftests/mm/guard-regions.c > +++ b/tools/testing/selftests/mm/guard-regions.c > @@ -1912,7 +1912,7 @@ TEST_F(guard_regions, hole_punch) > { > const unsigned long page_size = self->page_size; > char *ptr; > - int i; > + int i, ret; > > if (variant->backing == ANON_BACKED) > SKIP(return, "Truncation test specific to file-backed"); > @@ -1944,8 +1944,12 @@ TEST_F(guard_regions, hole_punch) > } > > /* Now hole punch the guarded region. */ > - ASSERT_EQ(madvise(&ptr[3 * page_size], 4 * page_size, > - MADV_REMOVE), 0); > + ret = madvise(&ptr[3 * page_size], 4 * page_size, MADV_REMOVE); > + if (ret == -1 && errno == EOPNOTSUPP) { > + ASSERT_EQ(munmap(ptr, 10 * page_size), 0); > + SKIP(return, "MADV_REMOVE not supported by filesystem"); > + } > + ASSERT_EQ(ret, 0); Correctly treats MADV_REMOVE EOPNOTSUPP as a missing prerequisite and unmaps before skipping Acked-by: Usama Arif <[email protected]> > > /* Ensure guard regions remain. */ > for (i = 0; i < 10; i++) { > -- > 2.47.3 > >
