On Tue, 18 Dec 2012, Chen Gang wrote:
> although we can not say it is surely a bug.
> it is better to set urb->hcpriv = NULL, after finish calling urb_free_priv.
> before kfree urb_priv, better to judge whether urb_priv == NULL, firstly.
>
> Signed-off-by: Chen Gang <gang.chen@xxxxxxxxxxx>
> ---
> drivers/usb/host/ohci-q.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c
> index 7482cfb..6671107 100644
> --- a/drivers/usb/host/ohci-q.c
> +++ b/drivers/usb/host/ohci-q.c
> @@ -12,8 +12,12 @@
>
> static void urb_free_priv (struct ohci_hcd *hc, urb_priv_t *urb_priv)
> {
> - int last = urb_priv->length - 1;
> + int last;
>
> + if (!urb_priv)
> + return;
> +
> + last = urb_priv->length - 1;
Please don't do this. If urb_priv is NULL, that's a bug. We want it
to cause a visible error, not silently fail.
> if (last >= 0) {
> int i;
> struct td *td;
> @@ -44,6 +48,7 @@ __acquires(ohci->lock)
> // ASSERT (urb->hcpriv != 0);
>
> urb_free_priv (ohci, urb->hcpriv);
> + urb->hcpriv = NULL;
> if (likely(status == -EINPROGRESS))
> status = 0;
This part is okay.
Alan Stern
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
