Re: [patch 3/3] KVM: MMU: prepopulate the shadow on invlpg

Avi Kivity
2008-11-02T16:14:17Z

Marcelo Tosatti wrote:

>> Okay, so Linux won't win on this. But is there any downside, apart from
>> fetching the pte and reestablishing the spte?
>>
>
> No, the downside is fetching the pte without being able to establish a
> valid spte.
>

That doesn't seem so expensive. Just a kvm_read_guest_atomic() with a
couple of bit tests for present/accessed.

(we do need to optimize copy_from_user_inatomic() to use a single mov insn)

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error compiling committee.c: too many arguments to function