From: Asai Thambi S P <asamymuthupa@micron.com>
Date: Fri, 11 Jan 2013 13:17:12 +0000 (+0530)
Subject: mtip32xx: fix for crash when the device surprise removed during rebuild
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=58c49df378cde4ff64172483d593a1a5689c13a8;p=linux-beck.git

mtip32xx: fix for crash when the device surprise removed during rebuild

When rebuild is in progress, disk->queue is yet to be created. Surprise
removing the device will call remove()-> del_gendisk(). del_gendisk()
expect disk->queue be not NULL. Fix is to call put_disk() when disk_queue
is NULL.

Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index b93282019632..3fd100990453 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3888,7 +3888,12 @@ static int mtip_block_remove(struct driver_data *dd)
 	 * Delete our gendisk structure. This also removes the device
 	 * from /dev
 	 */
-	del_gendisk(dd->disk);
+	if (dd->disk) {
+		if (dd->disk->queue)
+			del_gendisk(dd->disk);
+		else
+			put_disk(dd->disk);
+	}
 
 	spin_lock(&rssd_index_lock);
 	ida_remove(&rssd_index_ida, dd->index);
@@ -3922,7 +3927,13 @@ static int mtip_block_shutdown(struct driver_data *dd)
 		"Shutting down %s ...\n", dd->disk->disk_name);
 
 	/* Delete our gendisk structure, and cleanup the blk queue. */
-	del_gendisk(dd->disk);
+	if (dd->disk) {
+		if (dd->disk->queue)
+			del_gendisk(dd->disk);
+		else
+			put_disk(dd->disk);
+	}
+
 
 	spin_lock(&rssd_index_lock);
 	ida_remove(&rssd_index_ida, dd->index);