[to-be-updated] mm-migrate-fix-thps-mapcount-on-isolation.patch removed from -mm tree

[to-be-updated] mm-migrate-fix-thps-mapcount-on-isolation.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm: migrate: Fix THP's mapcount on isolation
has been removed from the -mm tree.  Its filename was
     mm-migrate-fix-thps-mapcount-on-isolation.patch

This patch was dropped because an updated version will be merged

------------------------------------------------------
From: Gavin Shan <gshan@redhat.com>
Subject: mm: migrate: Fix THP's mapcount on isolation
Date: Wed, 23 Nov 2022 08:57:52 +0800

The issue is reported when removing memory through virtio_mem device.  The
transparent huge page, experienced copy-on-write fault, is wrongly
regarded as pinned.  The transparent huge page is escaped from being
isolated in isolate_migratepages_block().  The transparent huge page can't
be migrated and the corresponding memory block can't be put into offline
state.

Fix it by replacing page_mapcount() with total_mapcount().  With this, the
transparent huge page can be isolated and migrated, and the memory block
can be put into offline state.

Link: https://lkml.kernel.org/r/20221123005752.161003-1-gshan@redhat.com
Fixes: 3917c80280c9 ("thp: change CoW semantics for anon-THP")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reported-by: Zhenyu Zhang <zhenyzha@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>	[v5.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/compaction.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/compaction.c~mm-migrate-fix-thps-mapcount-on-isolation
+++ a/mm/compaction.c
@@ -990,7 +990,7 @@ isolate_migratepages_block(struct compac
 		 * admittedly racy check.
 		 */
 		mapping = page_mapping(page);
-		if (!mapping && page_count(page) > page_mapcount(page))
+		if (!mapping && page_count(page) > total_mapcount(page))
 			goto isolate_fail;
 
 		/*
_

Patches currently in -mm which might be from gshan@redhat.com are