+ mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix.patch added to mm-unstable branch

+ mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix.patch

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

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days

------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Subject: mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix
Date: Wed, 14 Jan 2026 18:52:37 +0000

fix missed unlock, per Suren

Link: https://lkml.kernel.org/r/6fb9d6b4-ad39-41de-8db0-aa41a6406378@lucifer.local
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/rmap.c |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/mm/rmap.c~mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix
+++ a/mm/rmap.c
@@ -432,7 +432,7 @@ int anon_vma_fork(struct vm_area_struct
 static void cleanup_partial_anon_vmas(struct vm_area_struct *vma)
 {
 	struct anon_vma_chain *avc, *next;
-	bool locked = false;
+	struct anon_vma *root = NULL;
 
 	/*
 	 * We exclude everybody else from being able to modify anon_vma's
@@ -444,15 +444,18 @@ static void cleanup_partial_anon_vmas(st
 		struct anon_vma *anon_vma = avc->anon_vma;
 
 		/* All anon_vma's share the same root. */
-		if (!locked) {
-			anon_vma_lock_write(anon_vma);
-			locked = true;
+		if (!root) {
+			root = anon_vma->root;
+			anon_vma_lock_write(root);
 		}
 
 		anon_vma_interval_tree_remove(avc, &anon_vma->rb_root);
 		list_del(&avc->same_vma);
 		anon_vma_chain_free(avc);
 	}
+
+	if (root)
+		anon_vma_unlock_write(root);
 }
 
 /**
_

Patches currently in -mm which might be from lorenzo.stoakes@oracle.com are

mm-vma-do-not-leak-memory-when-mmap_prepare-swaps-the-file.patch
mm-remove-unnecessary-and-incorrect-mmap-lock-assert.patch
mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts.patch
mm-rmap-improve-anon_vma_clone-unlink_anon_vmas-comments-add-asserts-fix.patch
mm-rmap-skip-unfaulted-vmas-on-anon_vma-clone-unlink.patch
mm-rmap-remove-unnecessary-root-lock-dance-in-anon_vma-clone-unmap.patch
mm-rmap-remove-anon_vma_merge-function.patch
mm-rmap-make-anon_vma-functions-internal.patch
mm-mmap_lock-add-vma_is_attached-helper.patch
mm-rmap-allocate-anon_vma_chain-objects-unlocked-when-possible.patch
mm-rmap-allocate-anon_vma_chain-objects-unlocked-when-possible-fix.patch
mm-rmap-separate-out-fork-only-logic-on-anon_vma_clone.patch
mm-rmap-separate-out-fork-only-logic-on-anon_vma_clone-fix.patch