Re: Corrupted display changing screen colour depth in qemu-system-ppc/MacOS

[Gerd Hoffmann]

  Hi,

> > Can you try ditch the QEMU_ALLOCATED_FLAG check added by the commit?
> 
> Commit cb8962c146 drops the QEMU_ALLOCATED_FLAG check: if I add it back in
> with the following diff on top then everything works again:

Ah, the other way around.

> diff --git a/ui/console.c b/ui/console.c
> index 365a2c14b8..decae4287f 100644
> --- a/ui/console.c
> +++ b/ui/console.c
> @@ -2400,11 +2400,12 @@ static void vc_chr_open(Chardev *chr,
> 
>  void qemu_console_resize(QemuConsole *s, int width, int height)
>  {
> -    DisplaySurface *surface;
> +    DisplaySurface *surface = qemu_console_surface(s);
> 
>      assert(s->console_type == GRAPHIC_CONSOLE);
> 
> -    if (qemu_console_get_width(s, -1) == width &&
> +    if (surface && (surface->flags & QEMU_ALLOCATED_FLAG) &&
> +        qemu_console_get_width(s, -1) == width &&
>          qemu_console_get_height(s, -1) == height) {
>          return;
>      }
> 
> > Which depth changes triggers this?  Going from direct color to a
> > paletted mode?
> 
> A quick test suggests anything that isn't 32-bit colour is affected.

Hmm, I think the commit should simply be reverted.

Short-cutting the qemu_console_resize() call is only valid in case the
current surface was created by qemu_console_resize() too.  When it is
something else -- typically a surface backed by vga vram -- it's not.
Looking at the QEMU_ALLOCATED_FLAG checks exactly that ...

take care,
  Gerd