From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: Xen security advisory CVE-2011-1898 - VT-d (PCI
	passthrough) MSI
Date: Wed, 18 May 2011 11:03:48 +0100
Message-ID: <C9F95814.1A82E%keir.xen@gmail.com>
References: <1305708829.20907.108.camel@zakaz.uk.xensource.com>
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To: Ian Campbell <Ian.Campbell@eu.citrix.com>, "Cihula, Joseph" <joseph.cihula@intel.com>
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On 18/05/2011 09:53, "Ian Campbell" <Ian.Campbell@eu.citrix.com> wrote:

> On Mon, 2011-05-16 at 22:34 +0100, Cihula, Joseph wrote:
>>> -    if ( iommu_intremap )
>>> -    {
>>> +
>> 
>> Unless I'm misreading it, this will prevent users from specifying
>> "no-intremap" to disable the use of IR.
> 
> That wasn't my intention.
> 
>> Why would you keep the 'if ( iommu_intremap )' on the previous code
>> block but remove it here?
> 
> To be honest this change was a little bit unrelated, which was naughty
> of me. I saw:
> if ( iommu_intremap ) {
> THING A
> }
> if ( iommu_intremap ) {
> THING B
> }
> and changed it to
> if (iommu_intremap ) {
> THING A
> THING B
> }
> 
> Is there some subtlety to this code path that I've missed?

'THING A' conditionally clears iommu_intremap.

 -- Keir

> Ian.
> 
> 
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