From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f175.google.com (mail-wi0-f175.google.com [209.85.212.175]) by kanga.kvack.org (Postfix) with ESMTP id B81126B0038 for ; Wed, 5 Aug 2015 12:32:33 -0400 (EDT) Received: by wicgj17 with SMTP id gj17so199924745wic.1 for ; Wed, 05 Aug 2015 09:32:33 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id r9si29465117wiz.76.2015.08.05.09.32.32 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 05 Aug 2015 09:32:32 -0700 (PDT) Date: Wed, 5 Aug 2015 18:32:12 +0200 From: David Sterba 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 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> Sender: owner-linux-mm@kvack.org List-ID: 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 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, 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