From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1J4Il2-000300-US for qemu-devel@nongnu.org; Mon, 17 Dec 2007 11:23:57 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1J4Il0-0002xf-H8 for qemu-devel@nongnu.org; Mon, 17 Dec 2007 11:23:55 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1J4Il0-0002xc-Bs for qemu-devel@nongnu.org; Mon, 17 Dec 2007 11:23:54 -0500 Received: from mail.codesourcery.com ([65.74.133.4]) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1J4Ikz-0008Bd-Fc for qemu-devel@nongnu.org; Mon, 17 Dec 2007 11:23:54 -0500 From: Paul Brook Subject: Re: [Qemu-devel] [PATCH] ioemu/qemu vga: save and restore vram buffer (revised) Date: Mon, 17 Dec 2007 16:22:11 +0000 References: <18269.33299.414015.995882@mariner.uk.xensource.com> <18278.23285.98750.687170@mariner.uk.xensource.com> In-Reply-To: <18278.23285.98750.687170@mariner.uk.xensource.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200712171622.12475.paul@codesourcery.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: xen-devel@lists.xensource.com, Ian Jackson > In any case, vl.c's saving arrangements do save the buffer in > phys_ram_base - but that isn't what the guest sees in the VGA memory It doesn't matter what the guest physical mappings (if any) are. > area. The guest sees the vga memory-mapped IO registers (whose > meaning _is_ generally saved by vga.c), plus it can use the VGA memory > area and those control registers to access the whole of s->vram_ptr in > a bank-switched way. And it is that whole VGA memory buffer which is > `displayed' to (eg) vlc clients. If you look closer, you'll find that s->vram_ptr actually points to an offset from phys_ram_base. So the VGA framebuffer is already saved by ram_save. If the xen patches have changed this then you may need your patch. It has no business in mainstream qemu though. Paul