Re: [PATCH v7 09/11] KVM: MMU: introduce kvm_mmu_prepare_zap_obsolete_page

[Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>]

On 05/24/2013 01:39 PM, Xiao Guangrong wrote:

>>> if (kvm_mmu_prepare_zap_page(sp, list))
>>> 	hlist_del(sp->hlist);
>>>
>>> Or, i missed your suggestion?
>> My assumption is that we can leave obsolete shadow pages on hashtable
>> till commit_zap time.
> 
> Ah, i see.
> 
> Yes, i agree with your idea. I think we can only skip the obsolete-and-invalid
> page since the obsolete-but-unzapped page still affects the mmu's behaviour,
> for example, it can cause page write-protect, kvm_mmu_unprotect_page()
> can not work by skipping unzapped-obsolete pages.

kvm_mmu_unprotect_page() can work, we can skip obsolete pages too when detect
whether need to write-protect a page, it is easier to make the page become
writable when zapping obsolete pages.

Will update it following your idea, sorry for my noise.