RE: [PATCH] vmbus: use put_device() if device_register fail

[KY Srinivasan]

> -----Original Message-----
> From: devel <driverdev-devel-bounces@xxxxxxxxxxxxxxxxxxxxxx> On Behalf
> Of Arvind Yadav
> Sent: Saturday, March 17, 2018 11:48 PM
> To: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>; Haiyang Zhang
> <haiyangz@xxxxxxxxxxxxx>
> Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH] vmbus: use put_device() if device_register fail
> 
> if device_register() returned an error. Always use put_device()
> to give up the reference initialized.
> 
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
> ---
>  drivers/hv/vmbus_drv.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index bc65c4d..25da2f3 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -1358,6 +1358,7 @@ int vmbus_device_register(struct hv_device
> *child_device_obj)
>  	ret = device_register(&child_device_obj->device);
>  	if (ret) {
>  		pr_err("Unable to register child device\n");
> +		put_device(&child_device_obj->device);

If the registration failed; we would not have acquired the reference on the device and so
we should not be dropping the reference in the failure path.

K. Y
>  		return ret;
>  	}
> 
> --
> 2.7.4
> 
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