Re: Frame buffer corruptions with KVM >= 2.6.36

Takuya Yoshikawa
2010-10-15T06:40:03Z

(2010/10/14 21:38), Avi Kivity wrote:
> On 10/14/2010 02:36 PM, Jan Kiszka wrote:
>> >
>> >> and this commit just makes the
>> >> corruptions more likely. This may even be a QEMU issue in the cirrus/vga
>> >> model (both qemu-kvm and upstream show the effect).
>> >>
>> >
>> > What about -no-kvm?
>>
>> Just booted it (took ages), and the result was actually a completely
>> black screen. Kind of persistent corruption. This really looks like a
>> qemu issue now, maybe even a regression as I don't remember running into
>> such effects a while back.
>
> Worked fine for me (though yes it was slow - did tcg regress?).
>

I reread my commit but could not find any reason to make this corruption
in kernel side.

But at least, I want to make it clear whether my commit was just a magnifier
of this problem, I know that magnifier itself is bad, or not.

Though I'm now trying some debugging but have not got a way to show
kvm_vm_ioctl_get_dirty_log() is 100% correct yet.

If you have any idea please tell me!

Takuya