powerpc/spufs: Fix hash faults for kernel regions

powerpc/spufs: Fix hash faults for kernel regions

Commit ac29c64089b7 ("powerpc/mm: Replace _PAGE_USER with
_PAGE_PRIVILEGED") swapped _PAGE_USER for _PAGE_PRIVILEGED, and
introduced check_pte_access() which denied kernel access to
non-_PAGE_PRIVILEGED pages.

However, it didn't add _PAGE_PRIVILEGED to the hash fault handler
for spufs' kernel accesses, so the DMAs required to establish SPE
memory no longer work.

This change adds _PAGE_PRIVILEGED to the hash fault handler for
kernel accesses.

Fixes: ac29c64089b7 ("powerpc/mm: Replace _PAGE_USER with _PAGE_PRIVILEGED")
Cc: [email protected] # v4.7+
Signed-off-by: Jeremy Kerr <[email protected]>
Reported-by: Sombat Tragolgosol <[email protected]>
Reviewed-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>