Merge tag 'md/3.17-fixes' of git://neil.brown.name/md

Pull md bugfixes from Neil Brown:
 "Here are the bug-fixes I promised :-)

  Funny how you start looking for one and other start appearing.

   - raid6 data corruption during recovery
   - raid6 livelock
   - raid10 memory leaks"

* tag 'md/3.17-fixes' of git://neil.brown.name/md:
  md/raid10: always initialise ->state on newly allocated r10_bio
  md/raid10: avoid memory leak on error path during reshape.
  md/raid10: Fix memory leak when raid10 reshape completes.
  md/raid10: fix memory leak when reshaping a RAID10.
  md/raid6: avoid data corruption during recovery of double-degraded RAID6
  md/raid5: avoid livelock caused by non-aligned writes.

drivers/md/raid10.c

@@ -2953,6 +2953,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr,
 		 */
 		if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
 			end_reshape(conf);
+			close_sync(conf);
 			return 0;
 		}
 
@@ -3081,6 +3082,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr,
 			}
 
 			r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO);
+			r10_bio->state = 0;
 			raise_barrier(conf, rb2 != NULL);
 			atomic_set(&r10_bio->remaining, 0);
 
@@ -3269,6 +3271,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr,
 		if (sync_blocks < max_sync)
 			max_sync = sync_blocks;
 		r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO);
+		r10_bio->state = 0;
 
 		r10_bio->mddev = mddev;
 		atomic_set(&r10_bio->remaining, 0);
@@ -4384,6 +4387,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr,
 read_more:
 	/* Now schedule reads for blocks from sector_nr to last */
 	r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO);
+	r10_bio->state = 0;
 	raise_barrier(conf, sectors_done != 0);
 	atomic_set(&r10_bio->remaining, 0);
 	r10_bio->mddev = mddev;
@@ -4398,6 +4402,7 @@ read_more:
 		 * on all the target devices.
 		 */
 		// FIXME
+		mempool_free(r10_bio, conf->r10buf_pool);
 		set_bit(MD_RECOVERY_INTR, &mddev->recovery);
 		return sectors_done;
 	}
@@ -4410,7 +4415,7 @@ read_more:
 	read_bio->bi_private = r10_bio;
 	read_bio->bi_end_io = end_sync_read;
 	read_bio->bi_rw = READ;
-	read_bio->bi_flags &= ~(BIO_POOL_MASK - 1);
+	read_bio->bi_flags &= (~0UL << BIO_RESET_BITS);
 	read_bio->bi_flags |= 1 << BIO_UPTODATE;
 	read_bio->bi_vcnt = 0;
 	read_bio->bi_iter.bi_size = 0;

drivers/md/raid5.c

@@ -2922,7 +2922,7 @@ static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
 	      (!test_bit(R5_Insync, &dev->flags) || test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) &&
 	      !test_bit(R5_OVERWRITE, &fdev[0]->flags)) ||
 	     (sh->raid_conf->level == 6 && s->failed && s->to_write &&
-	      s->to_write < sh->raid_conf->raid_disks - 2 &&
+	      s->to_write - s->non_overwrite < sh->raid_conf->raid_disks - 2 &&
 	      (!test_bit(R5_Insync, &dev->flags) || test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))))) {
 		/* we would like to get this block, possibly by computing it,
 		 * otherwise read it if the backing disk is insync
@@ -3817,6 +3817,8 @@ static void handle_stripe(struct stripe_head *sh)
 				set_bit(R5_Wantwrite, &dev->flags);
 				if (prexor)
 					continue;
+				if (s.failed > 1)
+					continue;
 				if (!test_bit(R5_Insync, &dev->flags) ||
 				    ((i == sh->pd_idx || i == sh->qd_idx)  &&
 				     s.failed == 0))