Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761920AbdLSKja (ORCPT ); Tue, 19 Dec 2017 05:39:30 -0500 Received: from mail.netline.ch ([148.251.143.178]:48832 "EHLO netline-mail3.netline.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761906AbdLSKj1 (ORCPT ); Tue, 19 Dec 2017 05:39:27 -0500 Subject: Re: nouveau. swiotlb: coherent allocation failed for device 0000:01:00.0 size=2097152 From: =?UTF-8?Q?Michel_D=c3=a4nzer?= To: Tobias Klausmann , Mike Galbraith Cc: nouveau , =?UTF-8?Q?Christian_K=c3=b6nig?= , LKML , dri-devel , Ben Skeggs References: <1513620418.7113.51.camel@gmx.de> Message-ID: Date: Tue, 19 Dec 2017 11:39:24 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1484 Lines: 42 On 2017-12-19 11:37 AM, Michel Dänzer wrote: > On 2017-12-18 08:01 PM, Tobias Klausmann wrote: >> On 12/18/17 7:06 PM, Mike Galbraith wrote: >>> Greetings, >>> >>> Kernel bound workloads seem to trigger the below for whatever reason. >>>   I only see this when beating up NFS.  There was a kworker wakeup >>> latency issue, but with a bandaid applied to fix that up, I can still >>> trigger this. >> >> >> Hi, >> >> i have seen this one as well with my system, but i could not find an >> easy way to trigger it for bisecting purpose. If you can trigger it >> conveniently, a bisect would be nice! > > I'm seeing this (with the amdgpu and radeon drivers) when restic takes a > backup, creating memory pressure. I happen to have just finished > bisecting, the result is: > > 648bc3574716400acc06f99915815f80d9563783 is the first bad commit > commit 648bc3574716400acc06f99915815f80d9563783 > Author: Christian König > Date: Thu Jul 6 09:59:43 2017 +0200 > > drm/ttm: add transparent huge page support for DMA allocations v2 > > Try to allocate huge pages when it makes sense. > > v2: fix comment and use ifdef > > BTW, I haven't noticed any bad effects other than the dmesg splats, so maybe it's just noise about transient failures for which there is a proper fallback in place. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer