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Re: [Xen-devel] [PATCH] x86/mm: disallow mmu hypercalls for a dying doma

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] x86/mm: disallow mmu hypercalls for a dying domain
From: Kouya Shimura <kouya@xxxxxxxxxxxxxx>
Date: Fri, 27 Nov 2009 18:10:10 +0900
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I observed that dom0 kept on issuing a mmu_update hypercall while the
domain is dying. So I don't feel happy with it. 
But I'm ok if the patch is dropped.


Keir Fraser writes:
> Since the check is made with no locks held, I don't think any race can be
> completely avoided here. I'm not sure the performance argument holds much
> water either -- this just looks like a pointless extra check.
>  -- Keir
> On 27/11/2009 06:22, "Kouya Shimura" <kouya@xxxxxxxxxxxxxx> wrote:
> > The race condition should be avoided for efficiency.
> > 
> > Signed-off-by: Kouya Shimura <kouya@xxxxxxxxxxxxxx>
> > 

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