Re: [kvm-devel] [PATCH] KVM: add KVM_SYNC_SHADOW_WITH_USER ioctl (v2)

[Avi K. <av...@qu...>]

Anthony Liguori wrote:
>>>   
>>
>> With mmu notifiers (posted two minutes after this) shadow is 
>> implicitly synced with userspace.  Since it seems to be progressing 
>> rapidly, I won't apply this patch in the hope that mmu notifiers can 
>> be ready for 2.6.25.
>
> Does that mean that we'll only support ballooning on host kernels > 
> 2.6.25 are you going to do judo with debug registers to implement it 
> for older kernels?

Good question.  We may choose not to support it (distros may backport it 
if they wish), or do some evil hackery, or apply 
KVM_SYNC_SHADOW_WITH_USER _only_ to the external module.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.