From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37233) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W5Cst-0001oO-OF for qemu-devel@nongnu.org; Mon, 20 Jan 2014 06:19:21 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W5Csm-0001My-8T for qemu-devel@nongnu.org; Mon, 20 Jan 2014 06:19:15 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50752) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W5Csm-0001Mt-06 for qemu-devel@nongnu.org; Mon, 20 Jan 2014 06:19:08 -0500 Date: Mon, 20 Jan 2014 13:23:45 +0200 From: "Michael S. Tsirkin" Message-ID: <20140120112345.GA11565@redhat.com> References: <1387185088-16811-1-git-send-email-kraxel@redhat.com> <20131216115401.GA19233@redhat.com> <1387201577.28883.38.camel@nilsson.home.kraxel.org> <20131216192843.GB21330@redhat.com> <1387277686.12500.35.camel@nilsson.home.kraxel.org> <20131217115936.GA30168@redhat.com> <1387302966.12500.85.camel@nilsson.home.kraxel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1387302966.12500.85.camel@nilsson.home.kraxel.org> Subject: Re: [Qemu-devel] [PATCH v2] x86: gigabyte alignment for ram List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: qemu-devel@nongnu.org, Anthony Liguori On Tue, Dec 17, 2013 at 06:56:06PM +0100, Gerd Hoffmann wrote: > > I merged your patch but split it: q35 is separate and piix > > is separate. Would you like me to drop the q35 part then? > > If you are fine with q35 having only 2G lowmem keep it. It's safe. > > We can sort the mmconfig setup afterwards, then check if (and how) we'll > transition to 3G lowmem. Maybe we simply don't after all, with the > world moving to 64bit it doesn't matter that much whenever memory is > mapped above or below 4g. And for old 32bit guests there is always the > option to stick with piix which continues to offers up to 3.5G lowmem. > > cheers, > Gerd > Any update here? I'm worried 2G lowmem is a bit too aggressive, PAE still exists. If we want to support old bios, one way would be to add a new register to enable 3g lowmem. Or just ignore the issue with new machine types. -- MST