Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751855AbdIJUH2 (ORCPT ); Sun, 10 Sep 2017 16:07:28 -0400 Received: from scorn.kernelslacker.org ([45.56.101.199]:53390 "EHLO scorn.kernelslacker.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751614AbdIJUH0 (ORCPT ); Sun, 10 Sep 2017 16:07:26 -0400 Date: Sun, 10 Sep 2017 16:07:24 -0400 From: Dave Jones To: Al Viro Cc: Dave Chinner , "Darrick J. Wong" , Linux Kernel , linux-xfs@vger.kernel.org Subject: Re: iov_iter_pipe warning. Message-ID: <20170910200724.let6gkxhkvlg6nkr@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Al Viro , Dave Chinner , "Darrick J. Wong" , Linux Kernel , linux-xfs@vger.kernel.org References: <20170807201818.kykqzexce6ap6aik@codemonkey.org.uk> <20170828203130.y6dq5fqovev6wmrv@codemonkey.org.uk> <20170829042542.GO4757@magnolia> <20170906200337.b5wj3gpfebliindw@codemonkey.org.uk> <20170906234617.GW17782@dastard> <20170908010441.GZ5426@ZenIV.linux.org.uk> <20170910010756.hnmb233ch7pmnrlx@codemonkey.org.uk> <20170910025712.GC5426@ZenIV.linux.org.uk> <20170910160710.7myz4iel2mnvya3b@codemonkey.org.uk> <20170910200547.GD5426@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170910200547.GD5426@ZenIV.linux.org.uk> User-Agent: NeoMutt/20170609 (1.8.3) X-Spam-Note: SpamAssassin invocation failed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1401 Lines: 31 On Sun, Sep 10, 2017 at 09:05:48PM +0100, Al Viro wrote: > On Sun, Sep 10, 2017 at 12:07:10PM -0400, Dave Jones wrote: > > On Sun, Sep 10, 2017 at 03:57:21AM +0100, Al Viro wrote: > > > On Sat, Sep 09, 2017 at 09:07:56PM -0400, Dave Jones wrote: > > > > > > > With this in place, I'm still seeing -EBUSY from invalidate_inode_pages2_range > > > > which doesn't end well... > > > > > > Different issue, and I'm not sure why that WARN_ON() is there in the > > > first place. Note that in a similar situation generic_file_direct_write() > > > simply buggers off and lets the caller do buffered write... > > > > > > iov_iter_pipe() warning is a sign of ->read_iter() on pipe-backed iov_iter > > > putting into the pipe more than it claims to have done. > > > > (from a rerun after hitting that EBUSY warn; hence the taint) > > > > WARNING: CPU: 0 PID: 14154 at fs/iomap.c:1055 iomap_dio_rw+0x78e/0x840 > > ... and that's another invalidate_inode_pages2_range() in the same > sucker. Again, compare with generic_file_direct_write()... > > I don't believe that this one has anything splice-specific to do with it. > And its only relation to iov_iter_pipe() splat is that it's in the same > fs/iomap.c... The interesting part is that I'm hitting these two over and over now rather than the iov_iter_pipe warning. Could just be unlucky randomness though.. Dave