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) {