Re: [PATCH] USB: output an error message when the pipe type doesn'tmatch the endpoint type

From: Alan Stern
Date: Tue Aug 31 2010 - 10:16:37 EST


On Mon, 30 Aug 2010, Simon Arlott wrote:

> Commit f661c6f8c67bd55e93348f160d590ff9edf08904 adds a check of the pipe type if
> CONFIG_USB_DEBUG is enabled, but it doesn't output anything if this scenario
> occurs.
>
> Signed-off-by: Simon Arlott <simon@xxxxxxxxxxx>
> Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/usb/core/urb.c | 5 ++++-
> 1 files changed, 4 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
> index 419e6b3..c14fc08 100644
> --- a/drivers/usb/core/urb.c
> +++ b/drivers/usb/core/urb.c
> @@ -401,8 +401,11 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
> };
>
> /* Check that the pipe's type matches the endpoint's type */
> - if (usb_pipetype(urb->pipe) != pipetypes[xfertype])
> + if (usb_pipetype(urb->pipe) != pipetypes[xfertype]) {
> + dev_err(&dev->dev, "BOGUS urb xfer, pipe %x != type %x\n",
> + usb_pipetype(urb->pipe), pipetypes[xfertype]);
> return -EPIPE; /* The most suitable error code :-) */
> + }
>
> /* enforce simple/standard policy */
> allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT | URB_DIR_MASK |

This is okay with me. If you're serious about not changing the
behavior merely because debugging is enabled, you could move this test
out of the debug-only region and possibly change the dev_err to
dev_dbg. However doing so might break some devices that are currently
working.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/