From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Authentication-Results: smtp.codeaurora.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ds/57AmI" DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 97C02601D2 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932306AbeFFPpf (ORCPT + 25 others); Wed, 6 Jun 2018 11:45:35 -0400 Received: from mail-lf0-f65.google.com ([209.85.215.65]:42423 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932148AbeFFPpb (ORCPT ); Wed, 6 Jun 2018 11:45:31 -0400 X-Google-Smtp-Source: ADUXVKJ8DFMimVLdeNuyqph2La6xvUO4SUoRljbjeb3WWzJRf4V/SJv/ivtaqlV6fuQKnjSleB5Jh5KPWPJOu/Dp6Ec= MIME-Version: 1.0 In-Reply-To: References: <516cddbe-73c2-01f3-a552-0d9fd75ce63a@amd.com> <8f7d00f9-992f-cc07-6bd0-b1b47c5d2ccf@amd.com> From: Gabriel C Date: Wed, 6 Jun 2018 17:44:59 +0200 Message-ID: Subject: Re: Kernel and ADM hardware roulette ( was AMD graphics performance regression in 4.15 and later ) To: =?UTF-8?Q?Michel_D=C3=A4nzer?= Cc: =?UTF-8?Q?Christian_K=C3=B6nig?= , Jean-Marc Valin , Dave Airlie , Felix Kuehling , LKML , dri-devel@lists.freedesktop.org, alexander.deucher@amd.com, Andrew Morton , Linus Torvalds Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2018-06-06 17:03 GMT+02:00 Michel D=C3=A4nzer : > On 2018-06-06 04:44 PM, Christian K=C3=B6nig wrote: >> Am 06.06.2018 um 16:12 schrieb Michel D=C3=A4nzer: >>> On 2018-06-06 03:33 PM, Gabriel C wrote: >>>> 2018-06-06 14:19 GMT+02:00 Christian K=C3=B6nig : >>>>> Am 06.06.2018 um 14:08 schrieb Gabriel C: >>>>>> 2018-06-06 13:33 GMT+02:00 Christian K=C3=B6nig : >>>>>>> Am 06.06.2018 um 13:28 schrieb Gabriel C: >>> >>>>>> http://ftp.frugalware.org/pub/other/people/crazy/radeon/dmesg-iommu-= sr-iov-off.txt >>>>>> >>>>>> >>>>>> http://ftp.frugalware.org/pub/other/people/crazy/radeon/dmesg-iommu-= sr-iov-on.txt >>>>>> >>>>>> >>>>>> Also nothing else changed in that setup just testing kernel 4.17. >>>>> >>>>> >>>>> That has nothing TODO with the driver nor the original bug you >>>>> reported. The >>>>> problem is that SME is active and that is currently not supported at >>>>> all >>>>> with a that hardware. >>>> >>>> Ok .. so are we playing now kernel an AMD Hardware roulette on each >>>> release ? >>>> >>>> SME was like this in kernel 4.16.x here and all worked. >>> >>> If that is true, again please bisect which commit broke it. >>> >>> All the reports I've seen before this indicated that at least amdgpu >>> has never worked with SME (which BTW doesn't mean it's never going to >>> work or that we don't want to support it, just that as far as we know >>> it's currently not working). >> >> At least in theory it should work when we use the coherent DMA allocator= . >> >> When that really worked before, so the most likely commit which broke >> this is: >> >> commit fd5fd480dd8fe4910546e7b080b3ae345e57fe9f >> Author: Chunming Zhou >> Date: Fri Feb 9 10:44:09 2018 +0800 >> >> drm/amdgpu: only enable swiotlb alloc when need v2 >> >> get the max io mapping address of system memory to see if it is over >> our card accessing range. >> v2: move checking later >> >> Signed-off-by: Chunming Zhou >> Reviewed-by: Monk Liu >> Reviewed-by: Christian K=C3=B6nig >> Signed-off-by: Alex Deucher >> >> Currently looking into how we could somehow improve this detection. > > I guess this could fit for Gabriel, but e.g. > https://bugs.freedesktop.org/104437 says amdgpu was already broken with > SME in 4.15, if not 4.14 (I suspect there was simply no SME support > earlier). I got strange performance issue with 4.15 and 4.16 .. but SME was ON on that setup ( even before it hit mainline ) and never broke the GPU like = this. There is a 4.16.13 boot dmesg which has no such issue: http://ftp.frugalware.org/pub/other/people/crazy/radeon/dmesg-radeon-SME-ON= -kernel-4.16.txt With the setup as is booting 4.16.x works , while 4.17 trows the errors. > > > -- > Earthling Michel D=C3=A4nzer | http://www.amd= .com > Libre software enthusiast | Mesa and X developer