Comment 12 for bug 823494

Quoting : http://lists.gnu.org/archive/html/qemu-devel/2011-08/msg00710.html

On Thu, Aug 04, 2011 at 11:03:10AM -0500, Rick Vernam wrote:
> it seems that qxl is not working correctly with any of the 0.15 releases thus
> far. this includes qemu and qemu-kvm.
>
> when I start qemu like so:
> qemu-system-x86_64 -cpu host -enable-kvm -m 768 -usb -vga qxl -monitor stdio
> I get a black screen.

I recently had black screen problems with QXL in 0.14.x that turned out to
actually be a Seabios bug due to the default 64MB vram QXL has. I suspect
this would hit 0.15.x builds too. If this is what you're hitting, then
reducing the vram to 32MB is a temporary workaround that should help, eg

   -vga qxl -global qxl-vga.vram_size=33554432