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Date: Wed, 17 Nov 2010 18:02:39 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH] spice: add qxl device
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org

   Hi,

>>>> Better don't try ...
>>>
>>> Better prevent it then?
>>
>> How can I do that?

Question still stands:  Is there some way to disable hotplug for certain 
pci devices?

>>   How does this work btw?  Only
>> one vga adapter can drive the legacy vga ports, right?  Is there
>> some way to enable/disable this per vga device?
>
> Yes, just disable IO memory.

This is supposed to disable legacy vga ports (0x03c0+) too?

>>   If so: does qemu
>> emulate this correctly?
>
> It mostly does.

I doubt it actually enables/disables the legacy vga ports.

> But the counter wrapping will at least in theory crash qemu,
> this is an even bigger problem than a guest crash.

I can put it a limit at one million hotplugs or so ...

>>   I also don't see the point in plugging a display like
>> mad.
>
> Just to see if you can exploit some memory corruption maybe?

Can the guest do that without the hosts help?
Especially plugging *in* something?

cheers,
   Gerd