From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37840) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7owx-0002HC-Mj for qemu-devel@nongnu.org; Fri, 09 Aug 2013 11:50:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V7owo-0006JJ-6h for qemu-devel@nongnu.org; Fri, 09 Aug 2013 11:49:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45237) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7own-0006J4-VC for qemu-devel@nongnu.org; Fri, 09 Aug 2013 11:49:50 -0400 Date: Fri, 9 Aug 2013 18:51:25 +0300 From: "Michael S. Tsirkin" Message-ID: <20130809155125.GC19032@redhat.com> References: <1375979888-4879-1-git-send-email-aliguori@us.ibm.com> <520490D3.8010202@redhat.com> <8761vft4xf.fsf@codemonkey.ws> <5204EDFE.2020302@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5204EDFE.2020302@redhat.com> Subject: Re: [Qemu-devel] [PATCH] pc: drop external DSDT loading List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: Anthony Liguori , qemu-devel@nongnu.org On Fri, Aug 09, 2013 at 03:26:22PM +0200, Gerd Hoffmann wrote: > On 08/09/13 14:38, Anthony Liguori wrote: > > Gerd Hoffmann writes: > > > >> On 08/08/13 18:38, Anthony Liguori wrote: > >>> This breaks migration and is unneeded with modern SeaBIOS. > >> > >> No. Dropping for piix is fine. It will break q35 though. > > > > Can you elaborate? When Michael and I discussed this I was under the > > impression that latest SeaBIOS had full support for q35. > > SeaBIOS has the piix acpi tables compiled in, for the snake of backward > compatibility with old qemu versions which don't provide the acpi tables. > > With the q35 merge seabios started to provide the apci tables via > fw_cfg, for both q35 and piix, with the long-term goal to drop the > internal tables some day even for piix. > > Later on we figured table loading has live migration issues (due to bios > binary being migrated but acpi tables are not, so you can end up with > mismatches). > > The idea to deal with that was to simply turn off acpi table loading for > piix4, then wait for mst's acpi table patches which fix this for real > (including migration). Continue loading the tables on q35, ignoring the > live migration issue as ahci renders q35 unmigratable anyway. Sounds like a plan for 1.6. > I assumed that happend already, but looks like it slipped though, > otherwise you would not have posted that patch ... > > cheers, > Gerd