Re: [PATCH 3/4] Bug Fix drivers/pci/intel-iommu.c: convert paddr

David Woodhouse
2009-08-05T07:23:09Z

On Tue, 2009-08-04 at 15:10 -0700, Fenghua Yu wrote:
> When calling domain_pfn_mapping(), paddr should be converted to DMA pfn
> correctly instead just shift by VTD_PAGE_SHIFT.
>
> This issue causes kernel panic on PAGE_SIZE>VTD_PAGE_SIZE platforms e.g. ia64
> platforms.
>
> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>

Using the word 'alignment' somewhere in the above commit would have
confused me a lot less -- I got most of the way through composing a mail
asking how this patch wasn't a no-op, before I spotted it.

An alternative would be to align the size to DMA pages? Would that make
the sg case easier?

(Thanks for fixing this, btw)

--
dwmw2