[PATCH 4.9 112/148] axonram: Fix gendisk handling

Greg Kroah-Hartman
2017-12-12T13:07:44Z

From: Jan Kara <jack@suse.cz>

[ 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>
---
arch/powerpc/sysdev/axonram.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- 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_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);