From: Chris Wright <chrisw@sous-sol.org>
Date: Sat, 28 May 2011 18:15:02 +0000 (-0500)
Subject: intel-iommu: Check for identity mapping candidate using system dma mask
X-Git-Tag: v3.0-rc2~18^2~6
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8fcc5372fbac085199d84a880503ed67aba3fe49;p=pandora-kernel.git

intel-iommu: Check for identity mapping candidate using system dma mask

The identity mapping code appears to make the assumption that if the
devices dma_mask is greater than 32bits the device can use identity
mapping.  But that is not true: take the case where we have a 40bit
device in a 44bit architecture. The device can potentially receive a
physical address that it will truncate and cause incorrect addresses
to be used.

Instead check to see if the device's dma_mask is large enough
to address the system's dma_mask.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---

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