Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757929Ab3J2OzT (ORCPT ); Tue, 29 Oct 2013 10:55:19 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:39492 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757500Ab3J2OzR convert rfc822-to-8bit (ORCPT ); Tue, 29 Oct 2013 10:55:17 -0400 Message-Id: <526FDA6102000078000FDAE2@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.2 Date: Tue, 29 Oct 2013 14:55:13 +0000 From: "Jan Beulich" To: "Konrad Rzeszutek Wilk" Cc: "David Vrabel" , , "Bjorn Helgaas" , , "xen-devel" , , , , "linux-kernel@vger.kernel.org" Subject: Re: [v1 1/2] xen/p2m: Create identity mappings for PFNs beyound E820 and PCI BARs References: <1382713401-4882-1-git-send-email-konrad.wilk@oracle.com> <1382713401-4882-2-git-send-email-konrad.wilk@oracle.com> <20131028165837.GH4353@phenom.dumpdata.com> <526F7E9202000078000FD7A6@nat28.tlf.novell.com> <20131029144559.GI20487@phenom.dumpdata.com> In-Reply-To: <20131029144559.GI20487@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1294 Lines: 28 >>> On 29.10.13 at 15:45, Konrad Rzeszutek Wilk wrote: > On Tue, Oct 29, 2013 at 08:23:30AM +0000, Jan Beulich wrote: >> >>> On 28.10.13 at 17:58, Konrad Rzeszutek Wilk wrote: >> > On Fri, Oct 25, 2013 at 04:08:19PM -0600, Bjorn Helgaas wrote: >> >> If you can look at PCI host bridge apertures instead of BARs, that >> >> would solve both problems. Reassigning those apertures is >> >> theoretically possible but is not even a gleam in our eyes yet. >> > >> > I think I have to have both (BARs and host bridge apertures) as when >> > we do PCI passthrough to a guest - we might do it without a bridge. >> >> Why? Aren't the host bridge ranges necessarily a superset of the >> individual devices' BARs? > > Yes. But when you pass in a PCI device to a PV guest you don't pass in the > bridge. Just the PCI device itself. Right you are. Which means that basing the whole logic on the PCI device BARs is likely wrong anyway, not just because it doesn't account for other MMIO ranges. Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/