lkml.org 
[lkml]   [2014]   [May]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] mm: non-atomically mark page accessed during page cache allocation where possible -fix
Prabhakar Lad reported the following problem

I see following issue on DA850 evm,
git bisect points me to
commit id: 975c3a671f11279441006a29a19f55ccc15fb320
( mm: non-atomically mark page accessed during page cache allocation
where possible)

Unable to handle kernel paging request at virtual address 30e03501
pgd = c68cc000
[30e03501] *pgd=00000000
Internal error: Oops: 1 [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 1015 Comm: network.sh Not tainted 3.15.0-rc5-00323-g975c3a6 #9
task: c70c4e00 ti: c73d0000 task.ti: c73d0000
PC is at init_page_accessed+0xc/0x24
LR is at shmem_write_begin+0x54/0x60
pc : [<c0088aa0>] lr : [<c00923e8>] psr: 20000013
sp : c73d1d90 ip : c73d1da0 fp : c73d1d9c
r10: c73d1dec r9 : 00000000 r8 : 00000000
r7 : c73d1e6c r6 : c694d7bc r5 : ffffffe4 r4 : c73d1dec
r3 : c73d0000 r2 : 00000001 r1 : 00000000 r0 : 30e03501
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 0005317f Table: c68cc000 DAC: 00000015
Process network.sh (pid: 1015, stack limit = 0xc73d01c0)

pagep is set but not pointing to anywhere valid as it's an uninitialised
stack variable. This patch is a fix to
mm-non-atomically-mark-page-accessed-during-page-cache-allocation-where-possible.patch

Reported-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 2a7b9d1..0691481 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2459,7 +2459,7 @@ ssize_t generic_perform_write(struct file *file,
flags |= AOP_FLAG_UNINTERRUPTIBLE;

do {
- struct page *page;
+ struct page *page = NULL;
unsigned long offset; /* Offset into pagecache page */
unsigned long bytes; /* Bytes to write to page */
size_t copied; /* Bytes copied from user */

\
 
 \ /
  Last update: 2014-05-20 18:21    [W:0.419 / U:0.172 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site