mm/hmm: add a test for cross device private faults

Add a simple test case for when hmm_range_fault() is called with the
HMM_PFN_REQ_FAULT flag and a device private PTE is found for a device
other than the hmm_range::dev_private_owner.  This should cause the page
to be faulted back to system memory from the other device and the PFN
returned in the output array.

Also, remove a piece of code that unnecessarily unmaps part of the buffer.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ralph Campbell <[email protected]>
Reviewed-by: Alistair Popple <[email protected]>
Cc: Felix Kuehling <[email protected]>
Cc: Philip Yang <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions