From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: VGA Passthrough crashes machine Date: Thu, 15 Dec 2011 17:12:18 -0400 Message-ID: <20111215211218.GA15407@andromeda.dapyr.net> References: <4EE0A6C7.9080603@overnetdata.com> <20111214213819.GD25896@andromeda.dapyr.net> <4EEA1818.6060106@overnetdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4EEA1818.6060106@overnetdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Anthony Wright Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On Thu, Dec 15, 2011 at 03:54:00PM +0000, Anthony Wright wrote: > On 14/12/2011 21:38, Konrad Rzeszutek Wilk wrote: > > On Thu, Dec 08, 2011 at 12:00:07PM +0000, Anthony Wright wrote: > >> I've just had my first attempt at getting VGA passthrough to work, and > >> it crashed the machine. I'm trying to understand whether this is a > >> problem with my hardware, configuration or a software problem. > >> > >> I'm running Xen 4.1.2 with Linux 3.1.2 > >> > >> > >> The CPU is an Intel Core i5-650 > >> http://ark.intel.com/products/43546/Intel-Core-i5-650-Processor-%284M-Cache-3_20-GHz%29 > > And what is your motherboard? Does it have VT-d? > That was the important question... I'd missed the BIOS option to enable > VT-d which was disabled by default. I enabled the BIOS option and > everything worked, and it's very cool. :-) > > This does beg a couple of other questions though.... > > Shouldn't I get a nice(ish) error message if I try to start a VGA > passthrough VM on hardware that doesn't support it rather than crashing > the machine? There is this http://wiki.xen.org/xenwiki/VTdHowTo which gives you a nice idea of what works. > > Can I tell whether hardware will support VGA passthrough without trying > to start a VM that uses it? > > Also when I shut down the VM I have to use 'xl destroy' as I'm testing > with Windows. After issuing the 'xl destroy' there is a long pause and > then the error: > > libxl: error: libxl_device.c:470:libxl__wait_for_device_model Device > Model not ready > libxl: error: libxl_pci.c:892:do_pci_remove Device Model didn't > respond in time > > If I pass through more than one device, I get the pause and the message > for each device. Hm, it looks to be sending 'pci-rem' to the XenStore, but I am not sure if QEMU understands it. Did you compile Xen 4.1.2 by yourself? Did it compile with CONFIG_PASSTHROUGH? You should see some messages in the qemu.log about hot-remove and such.