drbd: bm_page_async_io: properly initialize page->private
authorArne Redlich <arne.redlich@googlemail.com>
Fri, 16 Mar 2012 07:19:33 +0000 (08:19 +0100)
committerPhilipp Reisner <philipp.reisner@linbit.com>
Wed, 9 May 2012 13:17:04 +0000 (15:17 +0200)
If bm_page_async_io is advised to use a new page for I/O
(BM_AIO_COPY_PAGES is set), it will get it from a mempool.
Once the mempool has to dip into its reserves the page is
not reinitialized, i.e. page->private contains garbage, which
will lead to various problems once the I/O completes (dereferences
of NULL pointers, the submitting thread getting stuck in D-state,
 ...).

Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
drivers/block/drbd/drbd_bitmap.c

index 39a1b0dafff4243d14fe54bdd2cc93ce8b764db2..a24eb787a7a1c454513b8ba8b777ced0234827cb 100644 (file)
@@ -205,7 +205,7 @@ void drbd_bm_unlock(struct drbd_conf *mdev)
 static void bm_store_page_idx(struct page *page, unsigned long idx)
 {
        BUG_ON(0 != (idx & ~BM_PAGE_IDX_MASK));
-       page_private(page) |= idx;
+       set_page_private(page, idx);
 }
 
 static unsigned long bm_page_to_idx(struct page *page)