path: root/mm
diff options
authorAl Viro <viro@ZenIV.linux.org.uk>2012-03-05 06:40:29 +0000
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-05 13:51:32 -0800
commitcd2934a3b3057eb048f8b4fb82e941d24a043207 (patch)
tree80bb0630c6f4b21fa47114a6226f9ef8aa448bc3 /mm
parent835ee7978cb47de94cf70232a694f19295d2993f (diff)
flush_tlb_range() needs ->page_table_lock when ->mmap_sem is not held
All other callers already hold either ->mmap_sem (exclusive) or ->page_table_lock. And we need it because some page table flushing instanced do work explicitly with ge tables. See e.g. arch/powerpc/mm/tlb_hash32.c, flush_tlb_range() and flush_range() in there. The same goes for uml, with a lot more extensive playing with page tables. Almost all callers are actually fine - flush_tlb_range() may have no need to bother playing with page tables, but it can do so safely; again, this caller is the sole exception - everything else either has exclusive ->mmap_sem on the mm in question, or mm->page_table_lock is held. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5f34bd8dda3..a876871f6be 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2277,8 +2277,8 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
list_add(&page->lru, &page_list);
- spin_unlock(&mm->page_table_lock);
flush_tlb_range(vma, start, end);
+ spin_unlock(&mm->page_table_lock);
mmu_notifier_invalidate_range_end(mm, start, end);
list_for_each_entry_safe(page, tmp, &page_list, lru) {