Merge tag 'md/4.6-rc6-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

Pull MD fixes from Shaohua Li:
 "This update includes several trival fixes.  The only important one is
  to fix MD bio merge, which has big performance impact"

* tag 'md/4.6-rc6-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  raid5: delete unnecessary warnning
  MD: make bio mergeable
  md/raid0: remove empty line printk from dump_zones
  md/raid0: fix uninitialized variable bug

drivers/md/md.c

@@ -284,6 +284,8 @@ static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
 	 * go away inside make_request
 	 */
 	sectors = bio_sectors(bio);
+	/* bio could be mergeable after passing to underlayer */
+	bio->bi_rw &= ~REQ_NOMERGE;
 	mddev->pers->make_request(mddev, bio);
 
 	cpu = part_stat_lock();

drivers/md/raid0.c

@@ -70,7 +70,6 @@ static void dump_zones(struct mddev *mddev)
 			(unsigned long long)zone_size>>1);
 		zone_start = conf->strip_zone[j].zone_end;
 	}
-	printk(KERN_INFO "\n");
 }
 
 static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
@@ -85,6 +84,7 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
 	struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
 	unsigned short blksize = 512;
 
+	*private_conf = ERR_PTR(-ENOMEM);
 	if (!conf)
 		return -ENOMEM;
 	rdev_for_each(rdev1, mddev) {

drivers/md/raid5.c

@@ -3502,8 +3502,6 @@ static void handle_stripe_clean_event(struct r5conf *conf,
 				dev = &sh->dev[i];
 			} else if (test_bit(R5_Discard, &dev->flags))
 				discard_pending = 1;
-			WARN_ON(test_bit(R5_SkipCopy, &dev->flags));
-			WARN_ON(dev->page != dev->orig_page);
 		}
 
 	r5l_stripe_write_finished(sh);