[PATCH] powerpc/iommu: Fix multiple issues with IOMMU pools code

[Alexander Graf]

Hi Anton,

On 04.10.2012, at 06:57, Anton Blanchard wrote:

> 
> Hi Alex,
> 
> Looks to be a preempt issue with the iommu pools code. I did find a
> couple more bugs along the way too.
> 
> Anton
> --
> 
> There are a number of issues in the recent IOMMU pools code:
> 
> - On a preempt kernel we might switch CPUs in the middle of building
>  a scatter gather list. When this happens the handle hint passed in
>  no longer falls within the local CPU's pool. Check for this and
>  fall back to the pool hint.
> 
> - We were missing a spin_unlock/spin_lock in one spot where we
>  switch pools.
> 
> - We need to provide locking around dart_tlb_invalidate_all and
>  dart_tlb_invalidate_one now that the global lock is gone.
> 
> Reported-by: Alexander Graf <agraf at suse.de>
> Signed-off-by: Anton Blanchard <anton at samba.org>
> ---
> 
> There is still an issue with the lazy u3 flushing, but I wanted
> to get this out for testing.

Yup. It fixes the nfs problem on my U4 based machine.

Tested-by: Alexander Graf <agraf at suse.de>

Alex