Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753112AbbHEQcg (ORCPT ); Wed, 5 Aug 2015 12:32:36 -0400 Received: from mx2.suse.de ([195.135.220.15]:43376 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751433AbbHEQcd (ORCPT ); Wed, 5 Aug 2015 12:32:33 -0400 Date: Wed, 5 Aug 2015 18:32:12 +0200 From: David Sterba To: mhocko@kernel.org Cc: LKML , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Andrew Morton , Johannes Weiner , Tetsuo Handa , Dave Chinner , "Theodore Ts'o" , linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, Jan Kara , Michal Hocko Subject: Re: [RFC 8/8] btrfs: use __GFP_NOFAIL in alloc_btrfs_bio Message-ID: <20150805163211.GB31669@twin.jikos.cz> Reply-To: dsterba@suse.com Mail-Followup-To: dsterba@suse.com, mhocko@kernel.org, LKML , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Andrew Morton , Johannes Weiner , Tetsuo Handa , Dave Chinner , Theodore Ts'o , linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, Jan Kara , Michal Hocko References: <1438768284-30927-1-git-send-email-mhocko@kernel.org> <1438768284-30927-9-git-send-email-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1438768284-30927-9-git-send-email-mhocko@kernel.org> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 811 Lines: 19 On Wed, Aug 05, 2015 at 11:51:24AM +0200, mhocko@kernel.org wrote: > From: Michal Hocko > > alloc_btrfs_bio is relying on GFP_NOFS to allocate a bio but since "mm: > page_alloc: do not lock up GFP_NOFS allocations upon OOM" this is > allowed to fail which can lead to > [ 37.928625] kernel BUG at fs/btrfs/extent_io.c:4045 > > This is clearly undesirable and the nofail behavior should be explicit > if the allocation failure cannot be tolerated. > > Signed-off-by: Michal Hocko Reviewed-by: David Sterba -- 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/