Impact: allow preemption in apply_to_pte_range updates to init_mm
Preemption is now allowed for lazy mmu mode, so don't disable
it for the inner loop of apply_to_pte_range. This only applies
when doing updates to init_mm; user pagetables are still modified
under the pte lock, so preemption is disabled anyway.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>