From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758599AbcLAMuq (ORCPT ); Thu, 1 Dec 2016 07:50:46 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:39166 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758218AbcLAMuo (ORCPT ); Thu, 1 Dec 2016 07:50:44 -0500 Subject: Re: next: Commit 'mm: Prevent __alloc_pages_nodemask() RCU CPU stall ...' causing hang on sparc32 qemu To: paulmck@linux.vnet.ibm.com References: <20161130012817.GH3924@linux.vnet.ibm.com> <20161130070212.GM3924@linux.vnet.ibm.com> <929f6b29-461a-6e94-fcfd-710c3da789e9@roeck-us.net> <20161130120333.GQ3924@linux.vnet.ibm.com> <20161130192159.GB22216@roeck-us.net> <20161130210152.GL3924@linux.vnet.ibm.com> <20161130231846.GB17244@roeck-us.net> <20161201011950.GX3924@linux.vnet.ibm.com> <20161201065657.GA4697@roeck-us.net> <20161201123409.GA3924@linux.vnet.ibm.com> Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , sparclinux@vger.kernel.org, davem@davemloft.net From: Guenter Roeck Message-ID: Date: Thu, 1 Dec 2016 04:50:40 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20161201123409.GA3924@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/01/2016 04:34 AM, Paul E. McKenney wrote: > On Wed, Nov 30, 2016 at 10:56:57PM -0800, Guenter Roeck wrote: >> Hi Paul, >> >> On Wed, Nov 30, 2016 at 05:19:50PM -0800, Paul E. McKenney wrote: >> [ ... ] >> >>>>>> >>>>>> BUG: sleeping function called from invalid context at mm/page_alloc.c:3775 >> [ ... ] >>> >>> Whew! You had me going for a bit there. ;-) >> >> Bisect results are here ... the culprit is, again, commit 2d66cccd73 ("mm: >> Prevent __alloc_pages_nodemask() RCU CPU stall warnings"), and reverting that >> patch fixes the problem. Good that you dropped it already :-). > > "My work is done." ;-) > > And apologies for the hassle. I have no idea what I was thinking when > I put the cond_resched_rcu_qs() there! > No worries. Cheers, Guenter