+ mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code.patch added to mm-new branch

+ mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: mm: convert WARN_ON_ONCE()'s to VM_WARN_ON_ONCE() in VMA lock code
has been added to the -mm mm-new branch.  Its filename is
     mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code.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: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
Subject: mm: convert WARN_ON_ONCE()'s to VM_WARN_ON_ONCE() in VMA lock code
Date: Tue, 10 Nov 2026 16:57:45 +0000

Now that VMA assertions are predicated on CONFIG_DEBUG_VM, it makes sense
to convert existing unconditional WARN_ON_ONCE()'s in VMA lock code to
VM_WARN_ON_ONCE()'s.

These are asserting programmatic invariants which are in most other cases
asserted using VM_WARN_ON_ONCE(), and there is simply no need for these to
be unconditionally checked, so no longer do so.

Link: https://lore.kernel.org/20261110-tame-vma-asserts-v1-3-be293ff499a7@kernel.org
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Liam R. Howlett (Google) <liam@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
---

 mm/mmap_lock.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/mm/mmap_lock.c~mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code
+++ a/mm/mmap_lock.c
@@ -146,7 +146,7 @@ int __vma_start_write(struct vm_area_str
 
 	err = __vma_start_exclude_readers(&ves);
 	if (err) {
-		WARN_ON_ONCE(ves.detached);
+		VM_WARN_ON_ONCE(ves.detached);
 		return err;
 	}
 
@@ -161,7 +161,7 @@ int __vma_start_write(struct vm_area_str
 	if (ves.exclusive) {
 		__vma_end_exclude_readers(&ves);
 		/* VMA should remain attached. */
-		WARN_ON_ONCE(ves.detached);
+		VM_WARN_ON_ONCE(ves.detached);
 	}
 
 	return 0;
@@ -193,7 +193,7 @@ void __vma_exclude_readers_for_detach(st
 		__vma_end_exclude_readers(&ves);
 	}
 	/* If an error arose but we were detached anyway, we don't care. */
-	WARN_ON_ONCE(!ves.detached);
+	VM_WARN_ON_ONCE(!ves.detached);
 }
 
 /* Do the VMA, mm seqcounts indicate the VMA is write locked? */
_

Patches currently in -mm which might be from ljs@kernel.org are

maintainers-remove-myself-from-mm-core-reviewership.patch
maintainers-remove-myself-from-mm-misc-reclaim-reviewership.patch
maintainers-remove-myself-from-mm-rust-reviewerships.patch
credits-add-entry-for-thp-maintenance.patch
mm-vma-predicate-vma_assert_stabilised-on-config_debug_vm.patch
revert-mm-khugepaged-remove-definition-of-struct-khugepaged_mm_slot.patch
mm-khugepaged-scan-mms-more-efficiently-under-mmap_lock-contention.patch
mm-khugepaged-release-contended-mmap-read-lock-after-scanning-enough-vmas.patch
mm-only-assert-mmap-locks-if-config_debug_vm-or-lockdep-is-set.patch
mm-only-assert-vma-locks-if-config_debug_vm-is-set.patch
mm-convert-warn_on_onces-to-vm_warn_on_once-in-vma-lock-code.patch