+ mm-fix-deferred-split-queue-races-during-migration-fix.patch added to mm-unstable branch

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

The patch titled
     Subject: mm-fix-deferred-split-queue-races-during-migration-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-fix-deferred-split-queue-races-during-migration-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-fix-deferred-split-queue-races-during-migration-fix.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: Zi Yan <ziy@nvidia.com>
Subject: mm-fix-deferred-split-queue-races-during-migration-fix
Date: Wed, 1 Apr 2026 18:52:43 -0400

move the comment

Link: https://lkml.kernel.org/r/FB71A764-0F10-4E5A-B4A0-BA4C7F138408@nvidia.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

--- a/mm/huge_memory.c~mm-fix-deferred-split-queue-races-during-migration-fix
+++ a/mm/huge_memory.c
@@ -4551,15 +4551,18 @@ retry:
 		}
 		folio_unlock(folio);
 next:
+		/*
+		 * If thp_underused() returns false, or if split_folio()
+		 * succeeds, or if split_folio() fails in the case it was
+		 * underused, then consider it used and don't add it back to
+		 * split_queue.
+		 */
 		if (did_split || !folio_test_partially_mapped(folio))
 			continue;
 requeue:
 		/*
-		 * Add back partially mapped folios, or underused folios
-		 * that we could not lock this round.  If thp_underused()
-		 * returns false, or if split_folio() succeeds, or if
-		 * split_folio() fails in the case it was underused, then
-		 * consider it used and don't add it back to split_queue.
+		 * Add back partially mapped folios, or underused folios that
+		 * we could not lock this round.
 		 */
 		fqueue = folio_split_queue_lock_irqsave(folio, &flags);
 		if (list_empty(&folio->_deferred_list)) {
_

Patches currently in -mm which might be from ziy@nvidia.com are

mm-fix-deferred-split-queue-races-during-migration-fix.patch