Places in the kernel where r13 is not the PACA pointer must have
maskable interrupts disabled, so r13 does not have to be restored when
returning from a soft-masked interrupt. We should never have
interrupts soft disabled when we're in user space.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>