From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Re: [vt-d][xen4-rc6] Hangs on startup Date: Mon, 22 Mar 2010 16:54:28 -0400 Message-ID: <20100322205428.GA428@phenom.dumpdata.com> References: <20100317201446.GA7785@phenom.dumpdata.com> <20100318141909.GA14445@phenom.dumpdata.com> <20100322195010.GB32073@phenom.dumpdata.com> <8115AF16522A3D4383C1FF753036713F9B3AAA31@cosmail01.lsi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <8115AF16522A3D4383C1FF753036713F9B3AAA31@cosmail01.lsi.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: "Nadolski, Ed" Cc: =?utf-8?B?xYF1a2FzeiBPbGXFmw==?= , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On Mon, Mar 22, 2010 at 03:06:48PM -0600, Nadolski, Ed wrote: > > > > -----Original Message----- > > > PCI back is to be used _only_ with PV guests - you on the other > > hand are running an HVM guest. > > > > Per the earlier statement, I would recommend you use the 'pciback' > > instead of 'pci-stub' or just not compile pciback in and see what > > happens. Keep in mind: PCI back module is only needed when you want to > > do PV PCI passthrough, which is not what you are doing. > > I'm confused - does that mean pci-stub must be used for device assignment to an HVM guest? The VTdHowTo isn't clear on that. Not per say. xen-pciback can be used for both PV and HVM. pci-stub can only be used for HVM guests. But there seems to be a bug somewhere that when the PCI device is assigned to pci-stub, pciback tries to seize it and can't find it and somehow is stuck in a spin-lock. That shouldn't be happening. Right now I am trying to figure out if we remove from Lukasza system pciback and only use pci-stub whether he still gets those MFN lookup errors with his QLogic card. Those are, I believe, a seperate issue from the pciback spinlock failure. > > Is there a way to bind the PCI devices to pci-stub at boot time, like with pciback? No. > Also, do the 'xm pci-list-assignable-devices' and 'xm pci-list' commands work the same for both pciback and pci-stub bindings? Yes. > > It seems odd to have different ways to do bindings for PV and for HVM. For example, would I have to switch the bindings if I want to first assign a device to a PV guest, then stop the PV guest and re-assign the device to an HVM guest? No if you use 'xen-pciback'. Yes if you use 'pci-stub'.