Re: IOMMU and graphics cards

From: Joerg Roedel
Date: Mon Jul 06 2009 - 09:12:28 EST


On Mon, Jul 06, 2009 at 01:26:17PM +0100, David Woodhouse wrote:
> On Fri, 2009-05-08 at 11:35 +0200, Joerg Roedel wrote:
> > The other way to achieve consistency is to remove the workaround from
> > VT-d code which significantly increases the chance to get the broken
> > stuff fixed. David?
>
> It's gone from 2.6.31-rc2, but even the in-tree drivers break, so I
> think we have to put it back for 2.6.31 (I've sent Linus the pull
> request already).
>
> I do intend to remove it again for 2.6.32 though, and I filed
> http://bugzilla.kernel.org/show_bug.cgi?id=13721
>
> For now it's got a clearer description ("Workaround broken graphics
> drivers") and defaults to 'n'.

Ok, cool, that sounds good. Which in-kernel DRM drivers break with IOMMU
for you? I'll may probably add a similar temporary workaround for AMD
IOMMU too...

Joerg

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