Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754119AbbBJLB2 (ORCPT ); Tue, 10 Feb 2015 06:01:28 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:39321 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750861AbbBJLB0 (ORCPT ); Tue, 10 Feb 2015 06:01:26 -0500 Date: Tue, 10 Feb 2015 12:01:16 +0100 From: Peter Zijlstra To: NeilBrown Cc: Tony Battersby , linux-raid@vger.kernel.org, lkml , axboe@kernel.dk, Linus Torvalds Subject: Re: RAID1 might_sleep() warning on 3.19-rc7 Message-ID: <20150210110116.GP24151@twins.programming.kicks-ass.net> References: <54D3D24E.5060303@cybernetics.com> <20150206085133.2c1ab892@notabene.brown> <20150206113930.GK23123@twins.programming.kicks-ass.net> <20150209121357.29f19d36@notabene.brown> <20150209091000.GN5029@twins.programming.kicks-ass.net> <20150210135017.7659e49c@notabene.brown> <20150210092936.GW21418@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150210092936.GW21418@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 866 Lines: 15 On Tue, Feb 10, 2015 at 10:29:36AM +0100, Peter Zijlstra wrote: > On Tue, Feb 10, 2015 at 01:50:17PM +1100, NeilBrown wrote: > > On Mon, 9 Feb 2015 10:10:00 +0100 Peter Zijlstra wrote: > > > > However, when io_schedule() explicitly calls blk_flush_plug(), then > > > > @from_schedule=false variant is used, and the unplug functions are allowed to > > > > allocate memory and block and maybe even call mempool_alloc() which might > > > > call io_schedule(). Note that as it stands recursively calling io_schedule() is already broken. Things like delayacct_blkio_{start,end}() do not nest properly. -- 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/