This is a note to let you know that I've just added the patch titled
mm: memory-failure: avoid false hwpoison page mapped error info
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-memory-failure-avoid-false-hwpoison-page-mapped-error-info.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From faeb2ff2c1c5cb60ce0da193580b256c941f99ca Mon Sep 17 00:00:00 2001
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Date: Thu, 27 Jul 2023 19:56:42 +0800
Subject: mm: memory-failure: avoid false hwpoison page mapped error info
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
commit faeb2ff2c1c5cb60ce0da193580b256c941f99ca upstream.
folio->_mapcount is overloaded in SLAB, so folio_mapped() has to be done
after folio_test_slab() is checked. Otherwise slab folio might be treated
as a mapped folio leading to false 'Someone maps the hwpoison page' error
info.
Link: https://lkml.kernel.org/r/20230727115643.639741-4-linmiaohe@xxxxxxxxxx
Fixes: 230ac719c500 ("mm/hwpoison: don't try to unpoison containment-failed pages")
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Acked-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/memory-failure.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2502,6 +2502,13 @@ int unpoison_memory(unsigned long pfn)
goto unlock_mutex;
}
+ if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reserved(folio))
+ goto unlock_mutex;
+
+ /*
+ * Note that folio->_mapcount is overloaded in SLAB, so the simple test
+ * in folio_mapped() has to be done after folio_test_slab() is checked.
+ */
if (folio_mapped(folio)) {
unpoison_pr_info("Unpoison: Someone maps the hwpoison page %#lx\n",
pfn, &unpoison_rs);
@@ -2514,9 +2521,6 @@ int unpoison_memory(unsigned long pfn)
goto unlock_mutex;
}
- if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reserved(folio))
- goto unlock_mutex;
-
ghp = get_hwpoison_page(p, MF_UNPOISON);
if (!ghp) {
if (PageHuge(p)) {
Patches currently in stable-queue which might be from linmiaohe@xxxxxxxxxx are
queue-6.4/hugetlb-do-not-clear-hugetlb-dtor-until-allocating-vmemmap.patch
queue-6.4/mm-memory-failure-avoid-false-hwpoison-page-mapped-error-info.patch
queue-6.4/mm-memory-failure-fix-potential-unexpected-return-value-from-unpoison_memory.patch
