Re: [Qemu-devel] [PATCH 5/5] vga-cirrus: Workaround during restore when using Xen.

[Anthony PERARD]

On Thu, Nov 24, 2011 at 18:30, Stefano Stabellini
<address@hidden> wrote:
>
>> @@ -2784,9 +2796,11 @@ static void cirrus_reset(void *opaque)
>>      }
>>      s->vga.cr[0x27] = s->device_id;
>>
>> -    /* Win2K seems to assume that the pattern buffer is at 0xff
>> -       initially ! */
>> -    memset(s->vga.vram_ptr, 0xff, s->real_vram_size);
>> +    if (!runstate_check(RUN_STATE_PREMIGRATE)) {
>> +        /* Win2K seems to assume that the pattern buffer is at 0xff
>> +           initially ! */
>> +        memset(s->vga.vram_ptr, 0xff, s->real_vram_size);
>> +    }
>>
>
> this is not too bad, I suppose that the videoram is going to be written
> again at restore time anyway so at least it saves some cycles

Actually, I think the next time that this vram will be written again
is, when the guest is actually "waked-up" and wrote something there.
Otherwise, the "restore" of the vram is done before QEMU start. So,
the memset could leave some weard stuff the screen (a white screen?).

-- 
Anthony PERARD