Sorry to disturb you, I realized you are a busy man of the community.

So I did some work before I email you.

I submit my proposal as you suggest, convert the two virtual driver (CIRRUS 

and BOCHS, if I remember it right) to atomic mode-setting.

After talked with Martin Peres(the administrator of xorg on gsoc) and 

Gerd Hoffmann (the author of VirtIO gpu driver), we got this question,

is CIRRUS suitable to convert, as qemu using cirrus considered harmful.

  

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