Hi Greg, On Fri, Jul 26, 2013 at 3:48 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 25 Jul 2013, Greg Kroah-Hartman wrote: > >> On Wed, Jul 03, 2013 at 10:53:09PM +0800, Ming Lei wrote: >> > The patch does the below improvement: >> > >> > - think QH_STATE_COMPLETING as unlinking state since all URBs on the >> > endpoint should be in unlinking or unlinked when doing endpoint_disable() >> > >> > - add "WARN_ON(!list_empty(&qh->qtd_list));" if qh->qh_state is >> > QH_STATE_LINKED because there shouldn't be any active transfer in qh >> >> If this can "never" happen, why spit a nasty message out to the error >> log? What can a user do with this? > > In this context, "never" means the only way it can happen is if there's > a serious bug in the way usbcore handles altsetting and config changes. > That code is sufficiently complicated that a little extra error > checking won't hurt, IMO. > > If it ever happens, a user could post the log message on the mailing > list, giving us a chance to find and fix the bug. > >> I really don't like adding stuff like this to the kernel if at all >> possible. > > Up to you. Still, I think bringing situations like this to people's > attention is a large part of what WARN_ON is intended for. Yes, I agree with Alan's comment. Could you merge this patchset since I have some following work which depends on this set? Or please let me know if resend is needed. Thanks, -- Ming Lei -- 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
