The patch titled
Subject: mm/memory_failure: initialize extra_pins in me_pagecache_clean()
has been added to the -mm tree. Its filename is
mm-shmem-dont-truncate-page-if-memory-failure-happens-fix.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-shmem-dont-truncate-page-if-memory-failure-happens-fix.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-shmem-dont-truncate-page-if-memory-failure-happens-fix.patch
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------------------------------------------------------
From: Nathan Chancellor <nathan@xxxxxxxxxx>
Subject: mm/memory_failure: initialize extra_pins in me_pagecache_clean()
Clang warns:
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
2 errors generated.
Initialize extra_pins to false so that it is not used uninitialized.
Link: https://lkml.kernel.org/r/20211021180336.2328086-1-nathan@xxxxxxxxxx
Fixes: d882a43a0011 ("mm: shmem: don't truncate page if memory failure happens")
Link: https://github.com/ClangBuiltLinux/linux/issues/1487
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx>
Acked-by: Yang Shi <shy828301@xxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory-failure.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/memory-failure.c~mm-shmem-dont-truncate-page-if-memory-failure-happens-fix
+++ a/mm/memory-failure.c
@@ -868,7 +868,7 @@ static int me_pagecache_clean(struct pag
{
int ret;
struct address_space *mapping;
- bool extra_pins;
+ bool extra_pins = false;
delete_from_lru_cache(p);
_
Patches currently in -mm which might be from nathan@xxxxxxxxxx are
mm-shmem-dont-truncate-page-if-memory-failure-happens-fix.patch
