[Nouveau] [PATCH] nouveau: fix page fault on device private memory

[Jason Gunthorpe]

On Fri, Jun 26, 2020 at 10:26:26AM -0700, Ralph Campbell wrote:
> If system memory is migrated to device private memory and no GPU MMU
> page table entry exists, the GPU will fault and call hmm_range_fault()
> to get the PFN for the page. Since the .dev_private_owner pointer in
> struct hmm_range is not set, hmm_range_fault returns an error which
> results in the GPU program stopping with a fatal fault.
> Fix this by setting .dev_private_owner appropriately.
> 
> Fixes: 08ddddda667b ("mm/hmm: check the device private page owner in hmm_range_fault()")
> Signed-off-by: Ralph Campbell <rcampbell at nvidia.com>
> ---
> 
> This is based on Linux-5.8.0-rc2 and is for Ben Skeggs nouveau tree.
> It doesn't depend on any of the other nouveau/HMM changes I have
> recently posted.

Makes sense to me

Reviewed-by: Jason Gunthorpe <jgg at mellanox.com>

Jason