Message-ID: <4A5F50CE.1060808@us.ibm.com>
Date: Thu, 16 Jul 2009 11:09:50 -0500
From: Anthony Liguori <aliguori@us.ibm.com>
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To: Gregory Haskins <ghaskins@novell.com>
CC: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, avi@redhat.com,
       glommer@redhat.com
Subject: Re: [KVM PATCH] KVM: introduce "xinterface" API for external interaction
 with guests
References: <20090716150323.29318.17714.stgit@dev.haskins.net> <20090716151945.29318.10882.stgit@dev.haskins.net> <4A5F4945.3080202@us.ibm.com> <4A5F4B96.6050409@novell.com>
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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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