+ selftests-mm-skip-guard-hole-punch-test-if-madv_remove-is-unsupported.patch added to mm-new branch

The patch titled
     Subject: selftests/mm: skip guard hole-punch test if MADV_REMOVE is unsupported
has been added to the -mm mm-new branch.  Its filename is
     selftests-mm-skip-guard-hole-punch-test-if-madv_remove-is-unsupported.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-skip-guard-hole-punch-test-if-madv_remove-is-unsupported.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Muhammad Usama Anjum <[email protected]>
Subject: selftests/mm: skip guard hole-punch test if MADV_REMOVE is unsupported
Date: Mon, 27 Jul 2026 10:52:18 +0100

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.

Link: https://lore.kernel.org/[email protected]
Signed-off-by: Muhammad Usama Anjum <[email protected]>
Tested-by: Sarthak Sharma <[email protected]>
Acked-by: Usama Arif <[email protected]>
Cc: Baolin Wang <[email protected]>
Cc: Barry Song <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Dev Jain <[email protected]>
Cc: Lance Yang <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Miaohe Lin <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Nico Pache <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 tools/testing/selftests/mm/guard-regions.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/tools/testing/selftests/mm/guard-regions.c~selftests-mm-skip-guard-hole-punch-test-if-madv_remove-is-unsupported
+++ a/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);
 
 	/* Ensure guard regions remain. */
 	for (i = 0; i < 10; i++) {
_

Patches currently in -mm which might be from [email protected] are

selftests-mm-unpoison-pages-in-memory-failure-teardown.patch
selftests-mm-skip-cow-tmpfile-cases-when-fallocate-is-unsupported.patch
selftests-mm-skip-guard-hole-punch-test-if-madv_remove-is-unsupported.patch
selftests-mm-skip-khugepaged-swap-tests-without-swap.patch
selftests-mm-skip-hard-dirty-page-cache-test-on-nfs.patch
selftests-mm-retry-migration-failures-for-the-full-runtime.patch