Re: [PATCH next] fixup! usb: xhci: reset endpoint on USB stall

[Sascha Hauer <s.hauer@pengutronix.de>]

On Fri, Mar 01, 2024 at 08:44:00AM +0100, Ahmad Fatoum wrote:
> usb: xhci: call dma_unmap_single in all error paths
> 
> A new early exit for stalled USB was added that resets the endpoint
> before returning an error code to the caller.
> 
> This unintentionally happened before unmapping the buffer, which is
> detected by CONFIG_DMA_API_DEBUG:
> 
>   usb2-0: Resetting EP 0...
>   WARNING: dwc3 2f00000.usb@2f00000.of: from-device mapping 0xbdf96680+0xff: duplicate mapping
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  drivers/usb/host/xhci-ring.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)

The patch is already in master, so I applied the fix there.

Sascha

> 
> diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
> index 5f68bc7c2f35..691d9c7463ad 100644
> --- a/drivers/usb/host/xhci-ring.c
> +++ b/drivers/usb/host/xhci-ring.c
> @@ -1045,15 +1045,16 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe,
>  
>  	record_transfer_result(udev, event, length);
>  	xhci_acknowledge_event(ctrl);
> -	if (udev->status == USB_ST_STALLED) {
> -		reset_ep(udev, ep_index, timeout_ms);
> -		return -EPIPE;
> -	}
>  
>  	/* Invalidate buffer to make it available to usb-core */
>  	if (length > 0)
>  		dma_unmap_single(ctrl->host.hw_dev, map, length, direction);
>  
> +	if (udev->status == USB_ST_STALLED) {
> +		reset_ep(udev, ep_index, timeout_ms);
> +		return -EPIPE;
> +	}
> +
>  	if (GET_COMP_CODE(le32_to_cpu(event->trans_event.transfer_len))
>  			== COMP_SHORT_TX) {
>  		/* Short data stage, clear up additional status stage event */
> -- 
> 2.39.2
> 
> 
> 

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