md: fix clearing of the 'changed' flags for the bad blocks list.

md: fix clearing of the 'changed' flags for the bad blocks list.

commit d0962936bff659d20522555b517582a2715fd23f upstream.

In super_1_sync (the first hunk) we need to clear 'changed' before
checking read_seqretry(), otherwise we might race with other code
adding a bad block and so won't retry later.

In md_update_sb (the second hunk), in the case where there is no
metadata (neither persistent nor external), we treat any bad blocks as
an error.  However we need to clear the 'changed' flag before calling
md_ack_all_badblocks, else it won't do anything.

This patch is suitable for -stable release 3.0 and later.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>