[merged mm-stable] mm-hwpoison-avoid-trying-to-unpoison-reserved-page.patch removed from -mm tree

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

The quilt patch titled
     Subject: mm, hwpoison: avoid trying to unpoison reserved page
has been removed from the -mm tree.  Its filename was
     mm-hwpoison-avoid-trying-to-unpoison-reserved-page.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm, hwpoison: avoid trying to unpoison reserved page
Date: Thu, 18 Aug 2022 21:00:16 +0800

For reserved pages, HWPoison flag will be set without increasing the page
refcnt.  So we shouldn't even try to unpoison these pages and thus
decrease the page refcnt unexpectly.  Add a PageReserved() check to filter
this case out and remove the below unneeded zero page (zero page is
reserved) check.

Link: https://lkml.kernel.org/r/20220818130016.45313-7-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory-failure.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/memory-failure.c~mm-hwpoison-avoid-trying-to-unpoison-reserved-page
+++ a/mm/memory-failure.c
@@ -2351,7 +2351,7 @@ int unpoison_memory(unsigned long pfn)
 		goto unlock_mutex;
 	}
 
-	if (PageSlab(page) || PageTable(page))
+	if (PageSlab(page) || PageTable(page) || PageReserved(page))
 		goto unlock_mutex;
 
 	ret = get_hwpoison_page(p, MF_UNPOISON);
@@ -2382,7 +2382,7 @@ int unpoison_memory(unsigned long pfn)
 		freeit = !!TestClearPageHWPoison(p);
 
 		put_page(page);
-		if (freeit && !(pfn == my_zero_pfn(0) && page_count(p) == 1)) {
+		if (freeit) {
 			put_page(page);
 			ret = 0;
 		}
_

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

mm-hwpoison-use-clearpagehwpoison-in-memory_failure.patch
mm-hwpoison-use-__pagemovable-to-detect-non-lru-movable-pages.patch
mm-hwpoison-use-num_poisoned_pages_sub-to-decrease-num_poisoned_pages.patch
mm-hwpoison-avoid-unneeded-page_mapped_in_vma-overhead-in-collect_procs_anon.patch
mm-hwpoison-check-pagetable-explicitly-in-hwpoison_user_mappings.patch
mm-hwpoison-cleanup-some-obsolete-comments.patch
writeback-remove-unused-macro-dirty_full_scope.patch