Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752776AbbGIOvY (ORCPT ); Thu, 9 Jul 2015 10:51:24 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38956 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750728AbbGIOvQ (ORCPT ); Thu, 9 Jul 2015 10:51:16 -0400 Date: Thu, 9 Jul 2015 07:45:40 -0700 From: Greg Kroah-Hartman To: Shuah Khan Cc: Linus Torvalds , Ming Lei , Shuah Khan , Linux Kernel Mailing List Subject: Re: Linux 4.2-rc1 Message-ID: <20150709144540.GA27723@kroah.com> References: <559E72B1.2050903@osg.samsung.com> <559E7AA4.6020602@osg.samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <559E7AA4.6020602@osg.samsung.com> User-Agent: Mutt/1.5.23+89 (0255b37be491) (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1520 Lines: 40 On Thu, Jul 09, 2015 at 07:44:04AM -0600, Shuah Khan wrote: > On 07/09/2015 07:10 AM, Shuah Khan wrote: > > On 07/08/2015 09:17 PM, Linus Torvalds wrote: > >> On Wed, Jul 8, 2015 at 5:58 PM, Ming Lei wrote: > >>> On Thu, Jul 9, 2015 at 1:29 AM, Linus Torvalds > >>> wrote: > >>>> Also, it looks like you need to hold the "fw_lock" to even look at > >>>> that pointer, since the buffer can get reallocated etc. > >>> > >>> Yes, the above code with holding 'fw_lock' is right fix for the issue since > >>> sysfs read can happen anytime, and there is one race between firmware > >>> request abort and reading uevent of sysfs. > >> > >> So if fw_priv->buf is NULL, what should we do? > >> > >> Should we skip the TIMEOUT= and ASYNC= fields too? > >> > >> Something like the attached, perhaps? > >> > >> Shuah, how reproducible is this? Does this (completely untested) patch > >> make any difference? > >> > > > > Happened both times I booted 4.2-rc1 up, so I would say 100% so far. > > I will test with your patch and report results. > > > > Yes. This patch fixed the problem. That's great, but what changed recently to cause this problem to happen? Any chance you can bisect to the problem commit? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/