brd: fix uninitialized use of brd->dax_dev

commit 1647b9b9 "brd: add dax_operations support" introduced the allocation
and freeing of a dax_device, but the allocated dax_device is not stored
into the brd_device, so brd_del_one() will eventually operate on an
uninitialized brd->dax_dev.

Fix this by storing the allocated dax_device to brd->dax_dev.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 5 insertions, 7 deletions

diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index bfa4ed2c75ef..ec00c01b8dc3 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -453,9 +453,7 @@ static struct brd_device *brd_alloc(int i)
 {
         struct brd_device *brd;
         struct gendisk *disk;
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-        struct dax_device *dax_dev;
-#endif
+
         brd = kzalloc(sizeof(*brd), GFP_KERNEL);
         if (!brd)
                 goto out;
@@ -497,8 +495,8 @@ static struct brd_device *brd_alloc(int i)
 
 #ifdef CONFIG_BLK_DEV_RAM_DAX
         queue_flag_set_unlocked(QUEUE_FLAG_DAX, brd->brd_queue);
-        dax_dev = alloc_dax(brd, disk->disk_name, &brd_dax_ops);
-        if (!dax_dev)
+        brd->dax_dev = alloc_dax(brd, disk->disk_name, &brd_dax_ops);
+        if (!brd->dax_dev)
                 goto out_free_inode;
 #endif
 
@@ -507,8 +505,8 @@ static struct brd_device *brd_alloc(int i)
 
 #ifdef CONFIG_BLK_DEV_RAM_DAX
 out_free_inode:
-        kill_dax(dax_dev);
-        put_dax(dax_dev);
+        kill_dax(brd->dax_dev);
+        put_dax(brd->dax_dev);
 #endif
 out_free_queue:
         blk_cleanup_queue(brd->brd_queue);