[PATCH] dup_mmap: update comment on new vma

Remove part of comment on linking new vma in dup_mmap: since anon_vma rmap
came in, try_to_unmap_one knows the vma without needing find_vma.  But add
a comment to note that here vma is inserted without mmap_sem.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/kernel/fork.c b/kernel/fork.c
index 876b31c..a28d11e 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -250,8 +250,9 @@ static inline int dup_mmap(struct mm_struct * mm, struct mm_struct * oldmm)
 
                /*
                 * Link in the new vma and copy the page table entries:
-                * link in first so that swapoff can see swap entries,
-                * and try_to_unmap_one's find_vma find the new vma.
+                * link in first so that swapoff can see swap entries.
+                * Note that, exceptionally, here the vma is inserted
+                * without holding mm->mmap_sem.
                 */
                spin_lock(&mm->page_table_lock);
                *pprev = tmp;