axonram: Fix gendisk handling

[ Upstream commit 672a2c87c83649fb0167202342ce85af9a3b4f1c ]

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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index 7a399b4d60a03a5a83d091113cfb257c45f92b39..566e8fc341f3a12ff92d393e01b8258570127162 100644 (file)
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -276,7 +276,9 @@ 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)
@@ -301,6 +303,7 @@ 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);