From a8a93f3f03b7a8008d720e8d91798efe599d416c Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 12 Feb 2009 13:45:34 -0800 Subject: [PATCH] mm: disable preemption in apply_to_pte_range Impact: bugfix Lazy mmu mode needs preemption disabled, so if we're apply to init_mm (which doesn't require any pte locks), then explicitly disable preemption. (Do it unconditionally after checking we've successfully done the allocation to simplify the error handling.) Signed-off-by: Jeremy Fitzhardinge --- mm/memory.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/memory.c b/mm/memory.c index baa999e87cd2..b80cc31292b1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1718,6 +1718,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, BUG_ON(pmd_huge(*pmd)); + preempt_disable(); arch_enter_lazy_mmu_mode(); token = pmd_pgtable(*pmd); @@ -1729,6 +1730,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, } while (pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); + preempt_enable(); if (mm != &init_mm) pte_unmap_unlock(pte-1, ptl); -- 2.39.5