Re: [PATCH 17/24] usb: host: xhci: Remove unused variable 'len'

[Greg Kroah-Hartman]

On Wed, May 26, 2021 at 02:00:30PM +0100, Lee Jones wrote:
> Fixes the following W=1 kernel build warning(s):
> 
>  drivers/usb/host/xhci.c: In function ‘xhci_unmap_temp_buf’:
>  drivers/usb/host/xhci.c:1349:15: warning: variable ‘len’ set but not used [-Wunused-but-set-variable]
> 
> Cc: Mathias Nyman <mathias.nyman@xxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: linux-usb@xxxxxxxxxxxxxxx
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> ---
>  drivers/usb/host/xhci.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index 27283654ca080..ac2a7d4288883 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -1346,7 +1346,6 @@ static bool xhci_urb_temp_buffer_required(struct usb_hcd *hcd,
>  
>  static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb)
>  {
> -	unsigned int len;
>  	unsigned int buf_len;
>  	enum dma_data_direction dir;
>  
> @@ -1362,10 +1361,10 @@ static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb)
>  				 dir);
>  
>  	if (usb_urb_dir_in(urb))
> -		len = sg_pcopy_from_buffer(urb->sg, urb->num_sgs,
> -					   urb->transfer_buffer,
> -					   buf_len,
> -					   0);
> +		sg_pcopy_from_buffer(urb->sg, urb->num_sgs,
> +				     urb->transfer_buffer,
> +				     buf_len,
> +				     0);

Sorry, but no, I keep rejecting this over and over, it needs to handle
the error handling properly and not paper over it like this :(

All the bots keep tripping up on it, you are not alone.

thanks,

greg k-h