The quilt patch titled
Subject: mm/mmap/vma_merge: use the proper vma pointers in cases 1 and 6
has been removed from the -mm tree. Its filename was
mm-mmap-vma_merge-use-the-proper-vma-pointers-in-cases-1-and-6.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm/mmap/vma_merge: use the proper vma pointers in cases 1 and 6
Date: Thu, 9 Mar 2023 12:12:51 +0100
Case 1 is now shown in the comment as next vma being merged with prev, so
use 'next' instead of 'mid'. In case 1 they both point to the same vma.
As a consequence, in case 6, the dup_anon_vma() is now tried first on
'next' and then on 'mid', before it was the opposite order. This is not a
functional change, as those two vma's cannnot have a different anon_vma,
as that would have prevented the merging in the first place.
Link: https://lkml.kernel.org/r/20230309111258.24079-4-vbabka@xxxxxxx
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mmap.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
--- a/mm/mmap.c~mm-mmap-vma_merge-use-the-proper-vma-pointers-in-cases-1-and-6
+++ a/mm/mmap.c
@@ -605,7 +605,7 @@ again:
/*
* In mprotect's case 6 (see comments on vma_merge),
- * we must remove the one after next as well.
+ * we are removing both mid and next vmas
*/
if (vp->remove2) {
vp->remove = vp->remove2;
@@ -948,13 +948,14 @@ struct vm_area_struct *vma_merge(struct
/* Can we merge both the predecessor and the successor? */
if (merge_prev && merge_next &&
is_mergeable_anon_vma(prev->anon_vma, next->anon_vma, NULL)) {
- remove = mid; /* case 1 */
+ remove = next; /* case 1 */
vma_end = next->vm_end;
- err = dup_anon_vma(prev, mid);
+ err = dup_anon_vma(prev, next);
if (mid != next) { /* case 6 */
+ remove = mid;
remove2 = next;
- if (!mid->anon_vma)
- err = dup_anon_vma(prev, next);
+ if (!next->anon_vma)
+ err = dup_anon_vma(prev, mid);
}
} else if (merge_prev) {
err = 0; /* case 2 */
_
Patches currently in -mm which might be from vbabka@xxxxxxx are
mm-page_alloc-use-check_pages_enabled-static-key-to-check-tail-pages.patch
