Re: [KVM PATCH] KVM: introduce "xinterface" API for external interactionwith guests

From: Anthony Liguori
Date: Thu Jul 16 2009 - 12:10:00 EST


Gregory Haskins wrote:
That said, I think the assumption that was made when I was using this
was that a proper ref for the page was acquired by the gfn_to_page() and
dropped by the caller. This was always used in the context of a
hypercall/vmexit so presumably the gpa should be considered stable
across that call. Is that not true?

If you're in kvm.ko, then yes, that's a safe assumption to make because the guest VCPU cannot run while you are running.

But you're opening this interface to any caller so the VCPU is likely to be running while someone calls this function

Regards,
-Greg




--
Regards,

Anthony Liguori

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