From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: PCI-passthrough for 32 bit guests and high MMIO addresses Date: Fri, 21 Nov 2014 15:01:12 +0000 Message-ID: <546F53B8.5040502@citrix.com> References: <546F4E86.8060801@suse.com> <546F60470200007800049D06@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Xrpim-0004xq-Kn for xen-devel@lists.xenproject.org; Fri, 21 Nov 2014 15:02:04 +0000 In-Reply-To: <546F60470200007800049D06@mail.emea.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich , Juergen Gross Cc: xen-devel List-Id: xen-devel@lists.xenproject.org On 21/11/14 14:54, Jan Beulich wrote: >>>> On 21.11.14 at 15:39, wrote: >> Trying to do PCI-passthrough with a 32-bit pv-domain I passed the >> wrong device to the domain. The MMIO address was too large for a >> MFN of a 32-bit system (it was 380003200000-3800036fffff). >> >> Instead of rejecting the operation Xen tried to perform it resulting >> in a (quite understandable) failure in the domU. >> >> I think either the hypervisor or the tools should refuse to do >> PCI-passthrough in this case. > What's wrong with this large an address? It is wider than 44 bits, so doesn't fit in a 32bit pfn for p2m/m2p update operations. ~Andrew