From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f47.google.com (mail-pa0-f47.google.com [209.85.220.47]) by kanga.kvack.org (Postfix) with ESMTP id DA54982F99 for ; Thu, 24 Dec 2015 06:07:02 -0500 (EST) Received: by mail-pa0-f47.google.com with SMTP id uo6so42639890pac.1 for ; Thu, 24 Dec 2015 03:07:02 -0800 (PST) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id va5si8280620pac.165.2015.12.24.03.07.01 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 24 Dec 2015 03:07:01 -0800 (PST) Subject: Re: [PATCH 1/2] mm, oom: introduce oom reaper From: Tetsuo Handa References: <1450204575-13052-1-git-send-email-mhocko@kernel.org> <20151224094758.GA22760@dhcp22.suse.cz> In-Reply-To: <20151224094758.GA22760@dhcp22.suse.cz> Message-Id: <201512242006.CGJ81784.SVMHOOQtLFFFOJ@I-love.SAKURA.ne.jp> Date: Thu, 24 Dec 2015 20:06:50 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org List-ID: To: mhocko@kernel.org, zwisler@gmail.com Cc: akpm@linux-foundation.org, mgorman@suse.de, rientjes@google.com, torvalds@linux-foundation.org, oleg@redhat.com, hughd@google.com, andrea@kernel.org, riel@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, ross.zwisler@linux.intel.com 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.) [ 235.768779] [] ? unmap_mapping_range+0x64/0x130 [ 235.769385] [] ? unmap_mapping_range+0x74/0x130 [ 235.770010] [] ? up_write+0x1f/0x40 [ 235.770501] [] ? unmap_mapping_range+0x74/0x130 -- 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