[PATCH] md: fix BUG in raid6 resync code.

From: NeilBrown <neilb@cse.unsw.edu.au>

This condtion on this loop is primarily to avoid the loop if it doesn't
appear to be needed.  However it optimises a little too much and there is a
case where it skips the loop when it is really needed.  This patch fixes
it.

This is the raid6 version of the recent raid5 resync bugfix.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/md/raid6main.c

@@ -1157,7 +1157,7 @@ static void handle_stripe(struct stripe_head *sh)
 	 * parity, or to satisfy requests
 	 * or to load a block that is being partially written.
 	 */
-	if (to_read || non_overwrite || (syncing && (uptodate+failed < disks))) {
+	if (to_read || non_overwrite || (syncing && (uptodate < disks))) {
 		for (i=disks; i--;) {
 			dev = &sh->dev[i];
 			if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) &&