[PATCH] md: delay starting md threads until array is completely setup

When an array is started we start one or two threads (two if there is a
reshape or recovery that needs to be completed).

We currently start these *before* the array is completely set up and in
particular before queue->queuedata is set.  If the thread actually starts
very quickly on another CPU, we can end up dereferencing queue->queuedata
and oops.

This patch also makes sure we don't try to start a recovery if a reshape is
being restarted.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 0 insertions, 3 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 5764387c6989..a02f35f1a796 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3246,9 +3246,6 @@ static int run(mddev_t *mddev)
                 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
                 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
                                                         "%s_reshape");
-                /* FIXME if md_register_thread fails?? */
-                md_wakeup_thread(mddev->sync_thread);
-
         }
 
         /* read-ahead size must cover two whole stripes, which is