axonram: Fix gendisk handling

It is invalid to call del_gendisk() when disk->queue is NULL. Fix error
handling in axon_ram_probe() to avoid doing that.

Also del_gendisk() does not drop a reference to gendisk allocated by
alloc_disk(). That has to be done by put_disk(). Add that call where
needed.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index ada29eaed6e2..f523ac883150 100644
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -274,7 +274,9 @@ failed:
                         if (bank->disk->major > 0)
                                 unregister_blkdev(bank->disk->major,
                                                 bank->disk->disk_name);
-                        del_gendisk(bank->disk);
+                        if (bank->disk->flags & GENHD_FL_UP)
+                                del_gendisk(bank->disk);
+                        put_disk(bank->disk);
                 }
                 device->dev.platform_data = NULL;
                 if (bank->io_addr != 0)
@@ -299,6 +301,7 @@ axon_ram_remove(struct platform_device *device)
         device_remove_file(&device->dev, &dev_attr_ecc);
         free_irq(bank->irq_id, device);
         del_gendisk(bank->disk);
+        put_disk(bank->disk);
         iounmap((void __iomem *) bank->io_addr);
         kfree(bank);