From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH] AMD IOMMU: Fix an interrupt remapping issue
	(v2)
Date: Mon, 11 Apr 2011 08:23:38 +0100
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To: Wei Wang2 <wei.wang2@amd.com>
Cc: Boris Ostrovsky <Boris.Ostrovsky@amd.com>, Wei Huang2 <Wei.Huang2@amd.com>, xen-devel@lists.xensource.com
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>>> On 08.04.11 at 18:52, Wei Wang2 <wei.wang2@amd.com> wrote:
> Jan, How dose this one look like to you?

Much better, but still not quite there: The unmasking must happen
*after* the writing of the upper half (if that's what is being modified).

You could also skip the unmasking altogether if saved_mask =3D=3D 1.

And if you start using __io_apic_write() (which I find very desirable)
is there a reason not to use it (and __io_apic_read()) in all of the
other places you touch anyway, too?

Jan