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Re: [Xen-devel] [PATCH] Allow programatic iomem permissions

To: Kieran Mansley <kmansley@xxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] Allow programatic iomem permissions
From: Keir Fraser <keir@xxxxxxxxxxxxx>
Date: Fri, 13 Jul 2007 17:20:53 +0100
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On 13/7/07 16:54, "Kieran Mansley" <kmansley@xxxxxxxxxxxxxx> wrote:

> Oops, sorry, forgot to refresh the patch before sending.  This one
> should compile better!

The put_page[_and_type] also needs to be on the far side of the TLB flush.
This is because if a refcount falls to zero then the page can change type
(e.g., to pagetable page) or be recycled to another domain! This is a safety
issue for Xen rather than for the granter. :-)

 -- Keir


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