+ mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4.patch added to mm-hotfixes-unstable branch

+ mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/vmscan: fix hwpoisoned large folio handling in shrink_folio_list
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4.patch

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

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------------------------------------------------------
From: Jinjiang Tu <tujinjiang@huawei.com>
Subject: mm/vmscan: fix hwpoisoned large folio handling in shrink_folio_list
Date: Fri, 11 Jul 2025 16:55:45 +0800

add comment to unmap_poisoned_folio()

Link: https://lkml.kernel.org/r/69fd4e00-1b13-d5f7-1c82-705c7d977ea4@huawei.com
Fixes: 1b0449544c64 ("mm/vmscan: don't try to reclaim hwpoison folio")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Reported-by: syzbot+3b220254df55d8ca8a61@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68412d57.050a0220.2461cf.000e.GAE@google.com/
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory-failure.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/mm/memory-failure.c~mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4
+++ a/mm/memory-failure.c
@@ -1561,6 +1561,10 @@ static int get_hwpoison_page(struct page
 	return ret;
 }
 
+/*
+ * The caller must guarantee the folio isn't large folio, except hugetlb.
+ * try_to_unmap() can't handle it.
+ */
 int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, bool must_kill)
 {
 	enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_SYNC | TTU_HWPOISON;
_

Patches currently in -mm which might be from tujinjiang@huawei.com are

mm-memory_hotplug-fix-hwpoisoned-large-folio-handling-in-do_migrate_range.patch
mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list.patch
mm-vmscan-fix-hwpoisoned-large-folio-handling-in-shrink_folio_list-v4.patch