[PATCH 4.11 047/115] powerpc/spufs: Fix hash faults for kernel regions

Greg Kroah-Hartman
2017-06-05T16:31:09Z

From: Jeremy Kerr <jk@ozlabs.org>

commit d75e4919cc0b6fbcbc8d6654ef66d87a9dbf1526 upstream.

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")
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Reported-by: Sombat Tragolgosol <sombat3960@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/platforms/cell/spu_base.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -197,7 +197,9 @@ static int __spu_trap_data_map(struct sp
(REGION_ID(ea) != USER_REGION_ID)) {

spin_unlock(&spu->register_lock);
- ret = hash_page(ea, _PAGE_PRESENT | _PAGE_READ, 0x300, dsisr);
+ ret = hash_page(ea,
+ _PAGE_PRESENT | _PAGE_READ | _PAGE_PRIVILEGED,
+ 0x300, dsisr);
spin_lock(&spu->register_lock);

if (!ret) {