From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753500AbbLXU4K (ORCPT ); Thu, 24 Dec 2015 15:56:10 -0500 Received: from mail-qk0-f193.google.com ([209.85.220.193]:33611 "EHLO mail-qk0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752474AbbLXU4I (ORCPT ); Thu, 24 Dec 2015 15:56:08 -0500 X-Greylist: delayed 975 seconds by postgrey-1.27 at vger.kernel.org; Thu, 24 Dec 2015 15:56:07 EST MIME-Version: 1.0 In-Reply-To: <201512242006.CGJ81784.SVMHOOQtLFFFOJ@I-love.SAKURA.ne.jp> References: <1450204575-13052-1-git-send-email-mhocko@kernel.org> <20151224094758.GA22760@dhcp22.suse.cz> <201512242006.CGJ81784.SVMHOOQtLFFFOJ@I-love.SAKURA.ne.jp> Date: Thu, 24 Dec 2015 13:39:51 -0700 Message-ID: Subject: Re: [PATCH 1/2] mm, oom: introduce oom reaper From: Ross Zwisler To: Tetsuo Handa Cc: Michal Hocko , Andrew Morton , Mel Gorman , David Rientjes , Linus Torvalds , Oleg Nesterov , Hugh Dickins , Andrea Argangeli , Rik van Riel , linux-mm@kvack.org, LKML , Ross Zwisler Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 24, 2015 at 4:06 AM, Tetsuo Handa wrote: > Michal Hocko wrote: >> This is VM_BUG_ON_PAGE(page_mapped(page), page), right? Could you attach >> the full kernel log? It all smells like a race when OOM reaper tears >> down the mapping and there is a truncate still in progress. But hitting >> the BUG_ON just because of that doesn't make much sense to me. OOM >> reaper is essentially MADV_DONTNEED. I have to think about this some >> more, though, but I am in a holiday mode until early next year so please >> bear with me. > > I don't know whether the OOM killer was invoked just before this > VM_BUG_ON_PAGE(). > >> Is this somehow DAX related? > > 4.4.0-rc6-next-20151223_new_fsync_v6+ suggests that this kernel > has "[PATCH v6 0/7] DAX fsync/msync support" applied. But I think > http://marc.info/?l=linux-mm&m=145068666428057 should be applied > when retesting. (20151223 does not have this fix.) No, DAX was not turned on, and while my fsync/msync patches were the initial reason I was testing (hence the new_fsync_v6 kernel name) they were not applied during the bisect, so I'm sure they are not related to this issue. I will retest with the patch referenced above, but it probably won't happen until the new year. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f53.google.com (mail-qg0-f53.google.com [209.85.192.53]) by kanga.kvack.org (Postfix) with ESMTP id 6301A82F99 for ; Thu, 24 Dec 2015 15:39:52 -0500 (EST) Received: by mail-qg0-f53.google.com with SMTP id o11so102808746qge.2 for ; Thu, 24 Dec 2015 12:39:52 -0800 (PST) Received: from mail-qk0-x244.google.com (mail-qk0-x244.google.com. [2607:f8b0:400d:c09::244]) by mx.google.com with ESMTPS id s5si11741074qki.65.2015.12.24.12.39.51 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Dec 2015 12:39:51 -0800 (PST) Received: by mail-qk0-x244.google.com with SMTP id t125so17158187qkh.2 for ; Thu, 24 Dec 2015 12:39:51 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <201512242006.CGJ81784.SVMHOOQtLFFFOJ@I-love.SAKURA.ne.jp> References: <1450204575-13052-1-git-send-email-mhocko@kernel.org> <20151224094758.GA22760@dhcp22.suse.cz> <201512242006.CGJ81784.SVMHOOQtLFFFOJ@I-love.SAKURA.ne.jp> Date: Thu, 24 Dec 2015 13:39:51 -0700 Message-ID: Subject: Re: [PATCH 1/2] mm, oom: introduce oom reaper From: Ross Zwisler Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: Michal Hocko , Andrew Morton , Mel Gorman , David Rientjes , Linus Torvalds , Oleg Nesterov , Hugh Dickins , Andrea Argangeli , Rik van Riel , linux-mm@kvack.org, LKML , Ross Zwisler On Thu, Dec 24, 2015 at 4:06 AM, Tetsuo Handa wrote: > Michal Hocko wrote: >> This is VM_BUG_ON_PAGE(page_mapped(page), page), right? Could you attach >> the full kernel log? It all smells like a race when OOM reaper tears >> down the mapping and there is a truncate still in progress. But hitting >> the BUG_ON just because of that doesn't make much sense to me. OOM >> reaper is essentially MADV_DONTNEED. I have to think about this some >> more, though, but I am in a holiday mode until early next year so please >> bear with me. > > I don't know whether the OOM killer was invoked just before this > VM_BUG_ON_PAGE(). > >> Is this somehow DAX related? > > 4.4.0-rc6-next-20151223_new_fsync_v6+ suggests that this kernel > has "[PATCH v6 0/7] DAX fsync/msync support" applied. But I think > http://marc.info/?l=linux-mm&m=145068666428057 should be applied > when retesting. (20151223 does not have this fix.) No, DAX was not turned on, and while my fsync/msync patches were the initial reason I was testing (hence the new_fsync_v6 kernel name) they were not applied during the bisect, so I'm sure they are not related to this issue. I will retest with the patch referenced above, but it probably won't happen until the new year. -- 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