Re: [PATCH v3 1/7] KVM: MMU: fix release noslot pfn

From: Avi Kivity
Date: Thu Sep 27 2012 - 12:26:03 EST


On 09/24/2012 02:32 PM, Xiao Guangrong wrote:

> 3 places after the whole patchset (There are some cleanups after this patch).
>
>> and one by even stronger is_error_pfn().
>
> This one is:
>
> | if (!is_error_pfn(pfn)) {
> | kvm_release_pfn_clean(pfn);
> | return true;
> | }
> |
> | return false;
>
> We can change it to:
>
> | if (is_error_pfn(pfn))
> | return false;
> |
> | kvm_release_pfn_clean(pfn);
> | return true;
>
>> I guess when/if other architectures will add MMIO MMU
>> caching they will need to guard kvm_release_pfn_clean() by is_noslot_pfn()
>> too in most cases. I am not insisting, but as this patch shows it is
>> easy to miss the check before calling the function.
>
> Sounds reasonable. I will consider it if Avi/Marcelo have no object on
> it.

I think it's a good idea.

Looks like we traded the unscalable error pages for these branches, I
think it's a reasonable tradeoff.

--
error compiling committee.c: too many arguments to function
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