[PATCH 1/8] mm: disable preemption in apply_to_pte_range
From: Jeremy Fitzhardinge
Date: Fri Mar 27 2009 - 14:02:56 EST
From: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
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 <jeremy.fitzhardinge@xxxxxxxxxx>
---
mm/memory.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index ef11ac6..27f8677 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1722,6 +1722,7 @@ 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);
@@ -1733,6 +1734,7 @@ 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);
--
1.6.0.6
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/