The patch titled
Subject: mm: shmem: fix uninitialized variable use in me_pagecache_clean()
has been added to the -mm tree. Its filename is
mm-shmem-dont-truncate-page-if-memory-failure-happens-fix-2.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-shmem-dont-truncate-page-if-memory-failure-happens-fix-2.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-shmem-dont-truncate-page-if-memory-failure-happens-fix-2.patch
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------------------------------------------------------
From: Arnd Bergmann <arnd@xxxxxxxx>
Subject: mm: shmem: fix uninitialized variable use in me_pagecache_clean()
It appears that the has_extra_refcount() is now in the wrong place:
mm/memory-failure.c:892:6: error: variable 'extra_pins' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (!mapping) {
^~~~~~~~
mm/memory-failure.c:915:32: note: uninitialized use occurs here
if (has_extra_refcount(ps, p, extra_pins))
^~~~~~~~~~
mm/memory-failure.c:892:2: note: remove the 'if' if its condition is always false
if (!mapping) {
^~~~~~~~~~~~~~~
mm/memory-failure.c:879:6: error: variable 'extra_pins' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (PageAnon(p)) {
^~~~~~~~~~~
mm/memory-failure.c:915:32: note: uninitialized use occurs here
if (has_extra_refcount(ps, p, extra_pins))
^~~~~~~~~~
mm/memory-failure.c:879:2: note: remove the 'if' if its condition is always false
if (PageAnon(p)) {
^~~~~~~~~~~~~~~~~~
mm/memory-failure.c:871:17: note: initialize the variable 'extra_pins' to silence this warning
bool extra_pins;
^
= 0
In both of those cases, we already set an error code and don't
need to override that one.
Link: https://lkml.kernel.org/r/20211022064748.4173718-1-arnd@xxxxxxxxxx
Fixes: d882a43a0011 ("mm: shmem: don't truncate page if memory failure happens")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory-failure.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/mm/memory-failure.c~mm-shmem-dont-truncate-page-if-memory-failure-happens-fix-2
+++ a/mm/memory-failure.c
@@ -909,12 +909,12 @@ static int me_pagecache_clean(struct pag
* Open: to take i_rwsem or not for this? Right now we don't.
*/
ret = truncate_error_page(p, page_to_pfn(p), mapping);
-out:
- unlock_page(p);
-
if (has_extra_refcount(ps, p, extra_pins))
ret = MF_FAILED;
+out:
+ unlock_page(p);
+
return ret;
}
_
Patches currently in -mm which might be from arnd@xxxxxxxx are
kasan-test-use-underlying-string-helpers.patch
posix-acl-avoid-wempty-body-warning.patch
memcg-kmem-further-deprecate-kmemlimit_in_bytes-fix.patch
mm-shmem-dont-truncate-page-if-memory-failure-happens-fix-2.patch
hfs-hfsplus-use-warn_on-for-sanity-check.patch
