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

To: Kouya Shimura <kouya@xxxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] x86/mm: disallow mmu hypercalls for a dying domain
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Fri, 27 Nov 2009 08:08:39 +0000
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Thread-topic: [Xen-devel] [PATCH] x86/mm: disallow mmu hypercalls for a dying domain
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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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