+ mm-mremap-permit-mremap-move-of-multiple-vmas-fix-2.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/mremap: reset VMI on unmap
has been added to the -mm mm-unstable branch.  Its filename is
     mm-mremap-permit-mremap-move-of-multiple-vmas-fix-2.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mremap-permit-mremap-move-of-multiple-vmas-fix-2.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 <lorenzo.stoakes@oracle.com>
Subject: mm/mremap: reset VMI on unmap
Date: Wed, 16 Jul 2025 20:29:54 +0100

Any separate VMA iterator may become invalidated when VMAs are unmapped at
nodes in proximity to the current position of the iterator.

Therefore, reset the iterator at each point where this occurs on a mremap
move.

Link: https://lkml.kernel.org/r/4fbf4271-6ab9-49c0-b30f-c8716bf19f09@lucifer.local
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mremap.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/mremap.c~mm-mremap-permit-mremap-move-of-multiple-vmas-fix-2
+++ a/mm/mremap.c
@@ -1112,6 +1112,7 @@ static void unmap_source_vma(struct vma_
 
 	err = do_vmi_munmap(&vmi, mm, addr, len, vrm->uf_unmap, /* unlock= */false);
 	vrm->vma = NULL; /* Invalidated. */
+	vrm->vmi_needs_reset = true;
 	if (err) {
 		/* OOM: unable to split vma, just get accounts right */
 		vm_acct_memory(len >> PAGE_SHIFT);
@@ -1367,6 +1368,7 @@ static unsigned long mremap_to(struct vm
 		err = do_munmap(mm, vrm->new_addr, vrm->new_len,
 				vrm->uf_unmap_early);
 		vrm->vma = NULL; /* Invalidated. */
+		vrm->vmi_needs_reset = true;
 		if (err)
 			return err;
 
_

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

mm-mremap-perform-some-simple-cleanups.patch
mm-mremap-refactor-initial-parameter-sanity-checks.patch
mm-mremap-put-vma-check-and-prep-logic-into-helper-function.patch
mm-mremap-cleanup-post-processing-stage-of-mremap.patch
mm-mremap-use-an-explicit-uffd-failure-path-for-mremap.patch
mm-mremap-check-remap-conditions-earlier.patch
mm-mremap-move-remap_is_valid-into-check_prep_vma.patch
mm-mremap-clean-up-mlock-populate-behaviour.patch
mm-mremap-permit-mremap-move-of-multiple-vmas.patch
mm-mremap-permit-mremap-move-of-multiple-vmas-fix.patch
mm-mremap-permit-mremap-move-of-multiple-vmas-fix-2.patch
tools-testing-selftests-extend-mremap_test-to-test-multi-vma-mremap.patch
mm-vma-refactor-vma_modify_flags_name-to-vma_modify_name.patch
mm-vma-refactor-vma_modify_flags_name-to-vma_modify_name-fix.patch
mm-mseal-always-define-vm_sealed.patch
mm-mseal-update-madvise-logic.patch
mm-mseal-small-cleanups.patch
mm-mseal-simplify-and-rename-vma-gap-check.patch
mm-mseal-rework-mseal-apply-logic.patch