From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: vga passthrough // questions about pci passthrough Date: Fri, 28 Sep 2012 10:12:22 +0200 Message-ID: <50655BE6.9050305@siemens.com> References: <50064D87.2090809@adiumentum.com> <50068134.4060306@siemens.com> <5006A72D.3080408@adiumentum.com> <5006ADF3.9030304@adiumentum.com> <1342621405.2229.194.camel@bling.home> <50081FBC.7060208@adiumentum.com> <1342714590.3142.4.camel@ul30vt> <5064364E.7050508@adiumentum.com> <1348768586.2320.204.camel@ul30vt.home> <50649E5C.6020808@adiumentum.com> <1348773491.2320.217.camel@ul30vt.home> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Martin Wolf , kvm@vger.kernel.org To: Alex Williamson Return-path: Received: from thoth.sbs.de ([192.35.17.2]:18855 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757103Ab2I1IM2 (ORCPT ); Fri, 28 Sep 2012 04:12:28 -0400 In-Reply-To: <1348773491.2320.217.camel@ul30vt.home> Sender: kvm-owner@vger.kernel.org List-ID: On 2012-09-27 21:18, Alex Williamson wrote: > On Thu, 2012-09-27 at 20:43 +0200, Martin Wolf wrote: >> thank you for the information. >> >> i will try what you mentioned... >> do you have some additional information about rebooting a VM with a >> passed through videocard? >> (amd / ati 7870) > > I don't. Is the bsod on reboot only or does it also happen on shutdown? > There's a slim chance it could be traced by enabling debug in the > pci-assign driver and analyzing what the guest driver is trying to do. > I'm hoping that q35 chipset support might resolve some issues with vga > assignment as it exposes a topology that looks a bit more like one that > a driver would expect on physical hardware. Thanks, >>From our attempts to get more working than what NVIDIA Quadro cards support officially, my own experiments with q35 in this context and our discussions with NVIDIA, I'm pretty skeptical that this chipset will make a difference here. Most problems are due to those non-standard side channels to configure the hardware, memory mappings etc. And getting this working requires either cooperation of the vendor or *a lot* of reverse engineering. Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux