Merge tag 'md-6.19-20251130' of gitolite.kernel.org:pub/scm/linux/kernel/git/mdraid/linux into for-6.19/block

Pull MD changes from Yu:

"- fix null-ptr-dereference regression for dm-raid0 (Yu Kuai)
 - fix IO hang for raid5 when array is broken with IO inflight (Yu Kuai)
 - remove legacy 1s delay to speed up system shutdown (Tarun Sahu)"

* tag 'md-6.19-20251130' of gitolite.kernel.org:pub/scm/linux/kernel/git/mdraid/linux:
  md: remove legacy 1s delay in md_notify_reboot
  md/raid5: fix IO hang when array is broken with IO inflight
  md: warn about updating super block failure
  md/raid0: fix NULL pointer dereference in create_strip_zones() for dm-raid

Author: axboe

drivers/md/md.c

@@ -2788,6 +2788,7 @@ void md_update_sb(struct mddev *mddev, int force_change)
 	if (!md_is_rdwr(mddev)) {
 		if (force_change)
 			set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
+		pr_err("%s: can't update sb for read-only array %s\n", __func__, mdname(mddev));
 		return;
 	}
 
@@ -10407,7 +10408,6 @@ static int md_notify_reboot(struct notifier_block *this,
 			    unsigned long code, void *x)
 {
 	struct mddev *mddev;
-	int need_delay = 0;
 
 	spin_lock(&all_mddevs_lock);
 	list_for_each_entry(mddev, &all_mddevs, all_mddevs) {
@@ -10421,21 +10421,11 @@ static int md_notify_reboot(struct notifier_block *this,
 				mddev->safemode = 2;
 			mddev_unlock(mddev);
 		}
-		need_delay = 1;
 		spin_lock(&all_mddevs_lock);
 		mddev_put_locked(mddev);
 	}
 	spin_unlock(&all_mddevs_lock);
 
-	/*
-	 * certain more exotic SCSI devices are known to be
-	 * volatile wrt too early system reboots. While the
-	 * right place to handle this issue is the given
-	 * driver, we do want to have a safe RAID driver ...
-	 */
-	if (need_delay)
-		msleep(1000);
-
 	return NOTIFY_DONE;
 }
 

drivers/md/raid0.c

@@ -68,7 +68,10 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
 	struct strip_zone *zone;
 	int cnt;
 	struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
-	unsigned int blksize = queue_logical_block_size(mddev->gendisk->queue);
+	unsigned int blksize = 512;
+
+	if (!mddev_is_dm(mddev))
+		blksize = queue_logical_block_size(mddev->gendisk->queue);
 
 	*private_conf = ERR_PTR(-ENOMEM);
 	if (!conf)
@@ -84,6 +87,10 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
 		sector_div(sectors, mddev->chunk_sectors);
 		rdev1->sectors = sectors * mddev->chunk_sectors;
 
+		if (mddev_is_dm(mddev))
+			blksize = max(blksize, queue_logical_block_size(
+				      rdev1->bdev->bd_disk->queue));
+
 		rdev_for_each(rdev2, mddev) {
 			pr_debug("md/raid0:%s:   comparing %pg(%llu)"
 				 " with %pg(%llu)\n",

drivers/md/raid5.c

@@ -4956,7 +4956,8 @@ static void handle_stripe(struct stripe_head *sh)
 		goto finish;
 
 	if (s.handle_bad_blocks ||
-	    test_bit(MD_SB_CHANGE_PENDING, &conf->mddev->sb_flags)) {
+	    (md_is_rdwr(conf->mddev) &&
+	     test_bit(MD_SB_CHANGE_PENDING, &conf->mddev->sb_flags))) {
 		set_bit(STRIPE_HANDLE, &sh->state);
 		goto finish;
 	}
@@ -6768,7 +6769,8 @@ static void raid5d(struct md_thread *thread)
 		int batch_size, released;
 		unsigned int offset;
 
-		if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
+		if (md_is_rdwr(mddev) &&
+		    test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
 			break;
 
 		released = release_stripe_list(conf, conf->temp_inactive_list);