From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Zeffertt Subject: Re: pciback bug "secondary bus reset failed" Date: Mon, 24 May 2010 17:53:01 +0100 Message-ID: <4BFAAEED.3050606@eu.citrix.com> References: <4BFAA0DD.3060900@eu.citrix.com> <20100524163023.GZ17817@reaktio.net> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20100524163023.GZ17817@reaktio.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: =?ISO-8859-1?Q?Pasi_K=E4rkk=E4inen?= Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Pasi K=E4rkk=E4inen wrote: > On Mon, May 24, 2010 at 04:53:01PM +0100, Alex Zeffertt wrote: >> Hi, >> >> I'm trying to passthrough a PCI network card to a domU guest, but I'm=20 >> hitting a bug that prevents the IRQ being unbound from dom0. >> >> Here are the steps I am taking: >> >> * configure Xen to pass $pci (0000:06:00.0) through to guest VM >> * unbind from current driver in dom0 and rebind to pciback: >> >> echo -n $pci > /sys/bus/pci/devices/$pci/driver/unbind >> modprobe pciback >> echo -n $pci > /sys/bus/pci/drivers/pciback/new_slot >> echo -n $pci > /sys/bus/pci/drivers/pciback/bind >> >> * start guest VM >> >> I then get the following on the dom0 console >> >> pciback 0000:06:00.0: secondary bus reset failed for device - all fu= nctions \ >> need to be co-assigned - err: 6 >> pciback 0000:06:00.0: FLR functionality not supported; attempts to u= se \ >> secondary bus reset unsuccessful; >> pciback 0000:06:00.0: FLR not performed for device >> >=20 > Please check this wiki page: > http://wiki.xensource.com/xenwiki/XenPCIpassthrough >=20 > It has a chapter about the "all functions need to be co-assigned" error= .. >=20 > -- Pasi Hi Pasi, Thanks for your reply. I think I understand what is happening now. My c= ard is=20 too old to have the Function Level Reset functionality. This leaves the=20 following options: 1. Assign all the cards that share the PCI bus (0000:06) to the same gu= est.=20 This enables the FLR functionality to be replaced by the bridge's "Second= ary Bus=20 Reset" functionality - or - 2. Apply the patch referred to on=20 http://wiki.xensource.com/xenwiki/XenPCIpassthrough to bypass the FLR If I can't do number #1 because some cards are in use by dom0 then I gues= s #2 is=20 the only option. But does #2 require that dom0 has never accessed the ca= rd?=20 Also, what if you reboot the domU - does the fact that you can't do an FL= R on=20 the card mean that there will be unpredictable results the 2nd time domU = tries=20 to initialise it? Thanks again, Alex