From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mel Gorman Subject: [PATCH] mm: non-atomically mark page accessed during page cache allocation where possible -fix Date: Tue, 20 May 2014 16:49:00 +0100 Message-ID: <20140520154900.GO23991@suse.de> References: <1399974350-11089-1-git-send-email-mgorman@suse.de> <1399974350-11089-19-git-send-email-mgorman@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Cc: Johannes Weiner , Vlastimil Babka , Jan Kara , Michal Hocko , Hugh Dickins , Peter Zijlstra , Dave Hansen , Linux Kernel , Linux-MM , Linux-FSDevel To: Andrew Morton Return-path: Content-Disposition: inline In-Reply-To: <1399974350-11089-19-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org 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 : [] lr : [] 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 Signed-off-by: Mel Gorman --- 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 */ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753556AbaETPtJ (ORCPT ); Tue, 20 May 2014 11:49:09 -0400 Received: from cantor2.suse.de ([195.135.220.15]:56530 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062AbaETPtH (ORCPT ); Tue, 20 May 2014 11:49:07 -0400 Date: Tue, 20 May 2014 16:49:00 +0100 From: Mel Gorman To: Andrew Morton Cc: Johannes Weiner , Vlastimil Babka , Jan Kara , Michal Hocko , Hugh Dickins , Peter Zijlstra , Dave Hansen , Linux Kernel , Linux-MM , Linux-FSDevel Subject: [PATCH] mm: non-atomically mark page accessed during page cache allocation where possible -fix Message-ID: <20140520154900.GO23991@suse.de> References: <1399974350-11089-1-git-send-email-mgorman@suse.de> <1399974350-11089-19-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1399974350-11089-19-git-send-email-mgorman@suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 : [] lr : [] 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 Signed-off-by: Mel Gorman --- 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 */