+ tools-testing-vma-add-tests-for-copy_vma-self-merge.patch added to mm-unstable branch

The patch titled
     Subject: tools/testing/vma: add tests for copy_vma() self-merge
has been added to the -mm mm-unstable branch.  Its filename is
     tools-testing-vma-add-tests-for-copy_vma-self-merge.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/tools-testing-vma-add-tests-for-copy_vma-self-merge.patch

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

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------------------------------------------------------
From: "Lorenzo Stoakes (ARM)" <[email protected]>
Subject: tools/testing/vma: add tests for copy_vma() self-merge
Date: Thu, 13 Aug 2026 18:32:25 +0100

Assert that a VMA can be moved backwards, forwards and between a preceding
VMA and its old self.

In the cases in which the VMA merges only with itself expect that to be
achieved by expanding its old self, so assert that these function
correctly.

However in the case of a merge between a preceding VMA and itself the
original VMA is removed, so assert that the preceding VMA replaces the one
passed in as vmap and the merge is as expected.

Link: https://lore.kernel.org/[email protected]
Signed-off-by: Lorenzo Stoakes (ARM) <[email protected]>
Acked-by: David Hildenbrand (Arm) <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Deucher <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Baolin Wang <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Barry Song <[email protected]>
Cc: Boris Brezillon <[email protected]>
Cc: Byungchul Park <[email protected]>
Cc: Chengming Zhou <[email protected]>
Cc: Chris Li <[email protected]>
Cc: Christan König <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Claudio Imbrenda <[email protected]>
Cc: Dave Airlie <[email protected]>
Cc: Dev Jain <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Gregory Price (Meta) <[email protected]>
Cc: Harry Yoo <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Huang Ray <[email protected]>
Cc: "Huang, Ying" <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Janosch Frank <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Joshua Hahn <[email protected]>
Cc: Kairui Song <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kemeng Shi <[email protected]>
Cc: Lance Yang <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Liviu Dudau <[email protected]>
Cc: Maarten Lankhorst <[email protected]>
Cc: Marc Rutland <[email protected]>
Cc: "Masami Hiramatsu (Google)" <[email protected]>
Cc: Matthew Auld <[email protected]>
Cc: Matthew Brost <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Maxime Ripard <[email protected]>
Cc: Miaohe Lin <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Namhyung kim <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Nhat Pham <[email protected]>
Cc: Nico Pache <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Pedro Falcato <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rakie Kim <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Steven Price <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Thomas Hellström <[email protected]>
Cc: Thomas Zimemrmann <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: xu xin <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 tools/testing/vma/tests/vma.c |   46 +++++++++++++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

--- a/tools/testing/vma/tests/vma.c~tools-testing-vma-add-tests-for-copy_vma-self-merge
+++ a/tools/testing/vma/tests/vma.c
@@ -33,7 +33,51 @@ static bool test_copy_vma(void)
 	struct mm_struct mm = {};
 	bool need_locks = false;
 	VMA_ITERATOR(vmi, &mm, 0);
-	struct vm_area_struct *vma, *vma_new, *vma_next;
+	struct vm_area_struct *vma, *vma_prev, *vma_new, *vma_next, *vma_orig;
+
+	/* Move forwards, adjacent to old self - self-merge. */
+
+	vma = alloc_and_link_vma(&mm, 0x1000, 0x2000, 1, vma_flags);
+	vma_set_anonymous(vma);
+	vma_orig = vma;
+	vma_new = copy_vma(&vma, 0x2000, 0x1000, 1, &need_locks);
+	ASSERT_EQ(vma_new, vma_orig);
+	ASSERT_EQ(vma, vma_orig);
+	ASSERT_EQ(vma_new->vm_start, 0x1000);
+	ASSERT_EQ(vma_new->vm_end, 0x3000);
+
+	cleanup_mm(&mm, &vmi);
+
+	/* Move backwards, adjacent to old self - self-merge. */
+
+	vma = alloc_and_link_vma(&mm, 0x2000, 0x3000, 2, vma_flags);
+	vma_set_anonymous(vma);
+	vma_orig = vma;
+	vma_new = copy_vma(&vma, 0x1000, 0x1000, 2, &need_locks);
+	ASSERT_EQ(vma_new, vma_orig);
+	ASSERT_EQ(vma, vma_orig);
+	ASSERT_EQ(vma_new->vm_start, 0x1000);
+	ASSERT_EQ(vma_new->vm_end, 0x3000);
+
+	cleanup_mm(&mm, &vmi);
+
+	/*
+	 * Move backwards between prior VMA and old self - self-merge and vma
+	 * updated to a new VMA.
+	 */
+
+	vma_prev = alloc_and_link_vma(&mm, 0x1000, 0x2000, 1, vma_flags);
+	vma_set_anonymous(vma_prev);
+	vma = alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, vma_flags);
+	vma_set_anonymous(vma);
+	vma_orig = vma;
+	vma_new = copy_vma(&vma, 0x2000, 0x1000, 3, &need_locks);
+	ASSERT_NE(vma_new, vma_orig);
+	ASSERT_EQ(vma_new, vma);
+	ASSERT_EQ(vma_new->vm_start, 0x1000);
+	ASSERT_EQ(vma_new->vm_end, 0x4000);
+
+	cleanup_mm(&mm, &vmi);
 
 	/* Move backwards and do not merge. */
 
_

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

mm-vma-introduce-vma-anon-page-offset-field-and-add-helpers.patch
mm-provide-vma_is_cow_mapping-and-remove-is_cow_mapping.patch
mm-introduce-linear_anon_page_index.patch
mm-abstract-vma_address-and-introduce-vma_anon_address.patch
mm-update-print_bad_page_map-to-show-anon-index-if-appropriate.patch
mm-introduce-and-use-vma_filebacked_address.patch
mm-vma-fix-self-merge-check-in-copy_vma.patch
tools-testing-vma-add-tests-for-copy_vma-self-merge.patch
mm-propagate-vma-anonymous-page-offset-on-map-remap-split-merge.patch
mm-rmap-track-whether-the-page-vma-mapped-pgoff-is-anonymous.patch
mm-clean-up-vma_address_end.patch
mm-huge_memory-update-remove_migration_pmd-to-accept-a-folio.patch
mm-migrate-calculate-large-folio-page-index-using-pfn.patch
mm-rmap-use-anon-pgoff-to-track-map_private-file-backed-anon-folios.patch
tools-testing-vma-expand-vma-merge-tests-to-assert-anon-pgoff.patch
tools-testing-selftests-mm-test-anonymous-page-offset-merge-behaviour.patch
mm-add-some-missing-includes-to-mm-local-headers.patch
maintainers-add-drivers-char-memc-to-mm-misc-memory-mapping-sections.patch