Re: [PATCH] pci: Reenable the AMD IOMMU if it's mysteriouslyvanished over suspend

From: Matthew Garrett
Date: Thu Sep 30 2010 - 13:39:56 EST


On Thu, Sep 30, 2010 at 11:38:28AM -0400, Matthew Garrett wrote:
> AMD's reference BIOS code had a bug that could result in the firmware
> failing to reenable the iommu on resume. It transpires that this causes
> certain less than desirable behaviour when it comes to PCI accesses, to
> whit them ending up somewhere near Bristol when the more desirable outcome
> was Edinburgh. Sadness ensues, perhaps along with filesystem corruption.
> Let's make sure that it gets turned back on.

Of course, this isn't actually sufficient - nothing in the iommu code
appears to reprogram the BAR, for instance. Joerg, how is this meant to
work?

--
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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