Merge tag 'md/4.3-rc7-fixes' of git://neil.brown.name/md

Pull md bug fixes from Neil Brown:
 "Two more bug fixes for md.

  One bugfix for a list corruption in raid5 because of incorrect
  locking.

  Other for possible data corruption when a recovering device is failed,
  removed, and re-added.

  Both tagged for -stable"

* tag 'md/4.3-rc7-fixes' of git://neil.brown.name/md:
  Revert "md: allow a partially recovered device to be hot-added to an array."
  md/raid5: fix locking in handle_stripe_clean_event()

2 files changed, 5 insertions, 4 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index c702de18207a..3fe3d04a968a 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8040,8 +8040,7 @@ static int remove_and_add_spares(struct mddev *mddev,
                        !test_bit(Bitmap_sync, &rdev->flags)))
                         continue;
 
-                if (rdev->saved_raid_disk < 0)
-                        rdev->recovery_offset = 0;
+                rdev->recovery_offset = 0;
                 if (mddev->pers->
                     hot_add_disk(mddev, rdev) == 0) {
                         if (sysfs_link_rdev(mddev, rdev))
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 49bb8d3ff9be..45933c160697 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3499,6 +3499,7 @@ returnbi:
                 }
         if (!discard_pending &&
             test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags)) {
+                int hash;
                 clear_bit(R5_Discard, &sh->dev[sh->pd_idx].flags);
                 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
                 if (sh->qd_idx >= 0) {
@@ -3512,16 +3513,17 @@ returnbi:
                  * no updated data, so remove it from hash list and the stripe
                  * will be reinitialized
                  */
-                spin_lock_irq(&conf->device_lock);
 unhash:
+                hash = sh->hash_lock_index;
+                spin_lock_irq(conf->hash_locks + hash);
                 remove_hash(sh);
+                spin_unlock_irq(conf->hash_locks + hash);
                 if (head_sh->batch_head) {
                         sh = list_first_entry(&sh->batch_list,
                                               struct stripe_head, batch_list);
                         if (sh != head_sh)
                                         goto unhash;
                 }
-                spin_unlock_irq(&conf->device_lock);
                 sh = head_sh;
 
                 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))