From: David Woodhouse Date: Tue, 15 Jun 2010 09:57:57 +0000 (+0100) Subject: intel-iommu: Force-disable IOMMU for iGFX on broken Cantiga revisions. X-Git-Tag: v2.6.35-rc4~64^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2d9e667efdfb4e986074d98e7d9a424003c7c43b;p=pandora-kernel.git intel-iommu: Force-disable IOMMU for iGFX on broken Cantiga revisions. Certain revisions of this chipset appear to be broken. There is a shadow GTT which mirrors the real GTT but contains pre-translated physical addresses, for performance reasons. When a GTT update happens, the translations are done once and the resulting physical addresses written back to the shadow GTT. Except sometimes, the physical address is actually written back to the _real_ GTT, not the shadow GTT. Thus we start to see faults when that physical address is fed through translation again. Signed-off-by: David Woodhouse --- Reading git-diff-tree failed