From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41303) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wx06l-0002IV-Qb for qemu-devel@nongnu.org; Tue, 17 Jun 2014 16:36:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Wx06d-0000J3-UT for qemu-devel@nongnu.org; Tue, 17 Jun 2014 16:35:55 -0400 Received: from emh01.mail.saunalahti.fi ([62.142.5.107]:56888) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wx06d-0000Hn-68 for qemu-devel@nongnu.org; Tue, 17 Jun 2014 16:35:47 -0400 Date: Tue, 17 Jun 2014 23:35:36 +0300 From: Pasi =?iso-8859-1?Q?K=E4rkk=E4inen?= Message-ID: <20140617203536.GW18930@reaktio.net> References: <1402077126-17799-1-git-send-email-dslutz@verizon.com> <1402077126-17799-3-git-send-email-dslutz@verizon.com> <20140617182237.GA15403@redhat.com> <53A08C99.4030403@terremark.com> <20140617194329.GF15610@redhat.com> <20140617200854.GC27242@laptop.dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140617200854.GC27242@laptop.dumpdata.com> Subject: Re: [Qemu-devel] [Xen-devel] [PATCH v5 2/3] pc & q35: Add new machine opt max-ram-below-4g List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xensource.com, Stefano Stabellini , "Michael S. Tsirkin" , qemu-devel@nongnu.org, Don Slutz , Anthony Liguori , Igor Mammedov , Andreas =?iso-8859-1?Q?F=E4rber?= On Tue, Jun 17, 2014 at 04:08:54PM -0400, Konrad Rzeszutek Wilk wrote: > On Tue, Jun 17, 2014 at 10:43:29PM +0300, Michael S. Tsirkin wrote: > > On Tue, Jun 17, 2014 at 02:44:41PM -0400, Don Slutz wrote: > > > > > > >Presumably you then have a 64 bit guest so why does it > > > >care about memory/MMIO being below 4G? > > > > > > It is not the guest that matters, it is all the PCI devices in use. There are > > > ones (all old hardware) that only support 32bit addresses. > > > > Emulated devices? Let's just teach them to support 64 bit BARs. > > Looks like a nicer solution than asking user to make > > this decision. > > I presume real normal PCI devices. > Yeah, I believe this thread is about enabling/fixing PCI passthru of (existing old legacy) physical PCI devices, so there's no way to "teach" them to support 64b BARs.. > > > > > When using > > > these you may need more room. > > > > > > Also pci-passthru of real hardware that is 32bit only may require this. > > > -Don Slutz > > -- Pasi From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pasi =?iso-8859-1?Q?K=E4rkk=E4inen?= Subject: Re: [Xen-devel] [PATCH v5 2/3] pc & q35: Add new machine opt max-ram-below-4g Date: Tue, 17 Jun 2014 23:35:36 +0300 Message-ID: <20140617203536.GW18930@reaktio.net> References: <1402077126-17799-1-git-send-email-dslutz@verizon.com> <1402077126-17799-3-git-send-email-dslutz@verizon.com> <20140617182237.GA15403@redhat.com> <53A08C99.4030403@terremark.com> <20140617194329.GF15610@redhat.com> <20140617200854.GC27242@laptop.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20140617200854.GC27242@laptop.dumpdata.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org To: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xensource.com, Stefano Stabellini , "Michael S. Tsirkin" , qemu-devel@nongnu.org, Don Slutz , Anthony Liguori , Igor Mammedov , Andreas =?iso-8859-1?Q?F=E4rber?= List-Id: xen-devel@lists.xenproject.org On Tue, Jun 17, 2014 at 04:08:54PM -0400, Konrad Rzeszutek Wilk wrote: > On Tue, Jun 17, 2014 at 10:43:29PM +0300, Michael S. Tsirkin wrote: > > On Tue, Jun 17, 2014 at 02:44:41PM -0400, Don Slutz wrote: > > > > > > >Presumably you then have a 64 bit guest so why does it > > > >care about memory/MMIO being below 4G? > > > > > > It is not the guest that matters, it is all the PCI devices in use. There are > > > ones (all old hardware) that only support 32bit addresses. > > > > Emulated devices? Let's just teach them to support 64 bit BARs. > > Looks like a nicer solution than asking user to make > > this decision. > > I presume real normal PCI devices. > Yeah, I believe this thread is about enabling/fixing PCI passthru of (existing old legacy) physical PCI devices, so there's no way to "teach" them to support 64b BARs.. > > > > > When using > > > these you may need more room. > > > > > > Also pci-passthru of real hardware that is 32bit only may require this. > > > -Don Slutz > > -- Pasi