Re: [PATCH] scsi/sg: fix checking return value of blk_get_queue()

[Marc Hartmayer]

On Wed, Jul 05, 2023 at 10:40 AM +0800, Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
>
> Commit fcaa174a9c99 ("scsi/sg: don't grab scsi host module reference")
> make a mess how blk_get_queue() is called, blk_get_queue() returns true
> on success while the caller expects it returns 0 on success.
>
> Fix this problem and also add a corresponding error message on failure.
>
> Fixes: fcaa174a9c99 ("scsi/sg: don't grab scsi host module reference")
> Reported-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx>
> Closes: https://lore.kernel.org/all/87lefv622n.fsf@xxxxxxxxxxxxx/
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> ---
>  drivers/scsi/sg.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
> index 89fa046c7158..0d8afffd1683 100644
> --- a/drivers/scsi/sg.c
> +++ b/drivers/scsi/sg.c
> @@ -1497,9 +1497,10 @@ sg_add_device(struct device *cl_dev)
>  	int error;
>  	unsigned long iflags;
>  
> -	error = blk_get_queue(scsidp->request_queue);
> -	if (error)
> -		return error;
> +	if (!blk_get_queue(scsidp->request_queue)) {
> +		pr_warn("%s: get scsi_device queue failed\n", __func__);
> +		return -ENODEV;
> +	}
>  
>  	error = -ENOMEM;
>  	cdev = cdev_alloc();
> -- 
> 2.39.2

Reviewed-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx>