From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756074Ab2LNOlG (ORCPT ); Fri, 14 Dec 2012 09:41:06 -0500 Received: from mail-vc0-f174.google.com ([209.85.220.174]:56311 "EHLO mail-vc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755097Ab2LNOlD (ORCPT ); Fri, 14 Dec 2012 09:41:03 -0500 Message-ID: <50CB3A7A.9040400@pobox.com> Date: Fri, 14 Dec 2012 09:40:58 -0500 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Xiaotian Feng CC: Xiaotian Feng , Jeff Garzik , James Bottomley , stable@kernel.org, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [libata] scsi: fix Null pointer dereference on disk error References: <1355386339-11411-1-git-send-email-xtfeng@gmail.com> In-Reply-To: <1355386339-11411-1-git-send-email-xtfeng@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/13/2012 03:12 AM, Xiaotian Feng wrote: > Following oops were observed when disk error happened: > > [ 4272.896937] sd 0:0:0:0: [sda] Unhandled error code > [ 4272.896939] sd 0:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK > [ 4272.896942] sd 0:0:0:0: [sda] CDB: Read(10): 28 00 00 5a de a7 00 00 08 00 > [ 4272.896951] end_request: I/O error, dev sda, sector 5955239 > [ 4291.574947] BUG: unable to handle kernel NULL pointer dereference at (null) > [ 4291.658305] IP: [] ahci_activity_show+0x1/0x40 > [ 4291.730090] PGD 76dbbc067 PUD 6c4fba067 PMD 0 > [ 4291.783408] Oops: 0000 [#1] SMP > [ 4291.822100] last sysfs file: /sys/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/sw_activity > [ 4291.934235] CPU 9 > [ 4291.958301] Pid: 27942, comm: hwinfo ...... > > ata_scsi_find_dev could return NULL, so ata_scsi_activity_{show,store} should check if atadev is NULL. > > Signed-off-by: Xiaotian Feng > Cc: Jeff Garzik > Cc: James Bottomley > Cc: stable@kernel.org > Cc: linux-ide@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > --- > drivers/ata/libata-scsi.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) applied