From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49616) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WT9c4-0006Y2-NT for qemu-devel@nongnu.org; Thu, 27 Mar 2014 08:40:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WT9bx-00009M-LG for qemu-devel@nongnu.org; Thu, 27 Mar 2014 08:40:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:27650) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WT9bx-000086-9r for qemu-devel@nongnu.org; Thu, 27 Mar 2014 08:40:45 -0400 Message-ID: <1395924027.12226.11.camel@nilsson.home.kraxel.org> From: Gerd Hoffmann Date: Thu, 27 Mar 2014 13:40:27 +0100 In-Reply-To: <87d2h8otg0.fsf@blackfin.pond.sub.org> References: <20140321133922.GA5707@aepfle.de> <87d2h8otg0.fsf@blackfin.pond.sub.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] emulating a display, instead of just a dumb graphics card List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Olaf Hering , qemu-devel@nongnu.org On Do, 2014-03-27 at 10:57 +0100, Markus Armbruster wrote: > Olaf Hering writes: > > > Right now qemu does appearently just emulate a graphics card (Cirrus for > > example), but not an attached monitor/display. The result is confusion > > in the guest OS. > > > > The current DRM drivers in upstream Linux seem to default to VESA modes. > > These are either provided by qemu, or Xorg uses a fixed internal list. > > As a result the VM window is 1280x960. Much too large for my native > > display. The kernel has a mode list. cirrusdrm used to default to the largest possible video mode, which is stupid and has been fixed meanwhile. It's 1024x748 now. > > It seems qemu does not provide a virtual display with valid EDID data. > > If it would start doing that, the host admin could force a certain > > display size. Ideally also with proper DPI data. > > > > Any idea if thats possible to implement? > > Not an expert in this area, but I can't see why it would be impossible. > Patches welcome. qxl can already signal the size of the display(s) to the guest. Where "display size" == "spice client window size". But it doesn't use edid for that. Simliar capabilities are planned for virtio-gpu. Not sure it is possible with cirrus. The hardware is pretty old, might be it predates edid ... stdvga is essentially paravirtual too (when it comes to capabilities beyond standard vga stuff) and has no interface to communicate preferred display size or edid blobs to the guest (yet?). cheers, Gerd