From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:41244) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QwUEJ-00012G-Bd for qemu-devel@nongnu.org; Thu, 25 Aug 2011 03:20:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QwUEI-0002xr-10 for qemu-devel@nongnu.org; Thu, 25 Aug 2011 03:19:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11645) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QwUEH-0002xm-NV for qemu-devel@nongnu.org; Thu, 25 Aug 2011 03:19:57 -0400 Message-ID: <4E55F799.2050103@redhat.com> Date: Thu, 25 Aug 2011 10:19:53 +0300 From: Avi Kivity MIME-Version: 1.0 References: <3d9d904a1e4939a147f8954c9e0d4cdaf3d44c31.1314033132.git.jan.kiszka@siemens.com> In-Reply-To: <3d9d904a1e4939a147f8954c9e0d4cdaf3d44c31.1314033132.git.jan.kiszka@siemens.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 5/6] vga: Use linear mapping + dirty logging in chain 4 memory access mode List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Anthony Liguori , qemu-devel , Gerd Hoffmann On 08/22/2011 08:12 PM, Jan Kiszka wrote: > Most VGA memory access modes require MMIO handling as they demand weird > logic to get a byte from or into the video RAM. However, there is one > exception: chain 4 mode with all memory planes enabled for writing. This > mode actually allows lineary mapping, which can then be combined with > dirty logging to accelerate KVM. > > This patch accelerates specifically VBE accesses like they are used by > grub in graphical mode. Not only the standard VGA adapter benefits from > this, also vmware and spice in VGA mode. > > On which version of grub does this work? This isn't having any effect on my Fedora grub. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.