[PATCH 4.9 094/102] md/raid10: reset the first at the end of loop

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Guoqing Jiang <gqjiang@xxxxxxxx>

commit 6f287ca6046edd34ed83aafb7f9033c9c2e809e2 upstream.

We need to set "first = 0' at the end of rdev_for_each
loop, so we can get the array's min_offset_diff correctly
otherwise min_offset_diff just means the last rdev's
offset diff.

[only the first chunk, due to b506335e5d2b ("md/raid10: skip spare disk as
'first' disk") being already applied - gregkh]

Suggested-by: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx>
Reviewed-by: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Cc: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/md/raid10.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3681,6 +3681,7 @@ static int raid10_run(struct mddev *mdde
 
 		if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
 			discard_supported = true;
+		first = 0;
 	}
 
 	if (mddev->queue) {