From: Doug Doan Date: Tue, 10 Aug 2010 00:18:30 +0000 (-0700) Subject: hugetlb: call mmu notifiers on hugepage cow X-Git-Tag: v2.6.36-rc1~475 X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=commitdiff_plain;h=3edd4fc9537d95e460d502987c63a90d6b9a7a82 hugetlb: call mmu notifiers on hugepage cow When a copy-on-write occurs, we take one of two paths in handle_mm_fault: through handle_pte_fault for normal pages, or through hugetlb_fault for huge pages. In the normal page case, we eventually get to do_wp_page and call mmu notifiers via ptep_clear_flush_notify. There is no callout to the mmmu notifiers in the huge page case. This patch fixes that. Signed-off-by: Doug Doan Acked-by: Mel Gorman Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 54d42b009dbe..b61d2db9f34e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2349,11 +2349,17 @@ retry_avoidcopy: ptep = huge_pte_offset(mm, address & huge_page_mask(h)); if (likely(pte_same(huge_ptep_get(ptep), pte))) { /* Break COW */ + mmu_notifier_invalidate_range_start(mm, + address & huge_page_mask(h), + (address & huge_page_mask(h)) + huge_page_size(h)); huge_ptep_clear_flush(vma, address, ptep); set_huge_pte_at(mm, address, ptep, make_huge_pte(vma, new_page, 1)); /* Make the old page be freed below */ new_page = old_page; + mmu_notifier_invalidate_range_end(mm, + address & huge_page_mask(h), + (address & huge_page_mask(h)) + huge_page_size(h)); } page_cache_release(new_page); page_cache_release(old_page);