On Sat, 18 Aug 2012, Bruno Prémont wrote: > Hi Jiri, > > [CCing Alan Stern] > > On Thu, 16 August 2012 Jiri Kosina <jkosina@xxxxxxx> wrote: > > On Thu, 16 Aug 2012, Bruno Prémont wrote: > > > > > > I don't really understand this explanation. Once usb_kill_urb() returns, > > > > the URB should be available for future use (and therefore all queues > > > > completely drained). > > > > > > I won't have time today to check, though my guess is that on each > > > echo $usb-id > bind; echo $usb-id > unbind > > > under /sys/bus/hid/drivers/hid-picolcd/ the USB urb queue fills a bit does > > > not get cleared. > > > > > > Is usb_kill_urb() called when unbinding just the specific hid driver? > > > > Yup, through hid_hw_stop() -> usbhid_stop(). > > > > > If so my short timing between bind/unbind must be triggering something > > > else... > > > > > > Otherwise I'm missing something as at first time I got no "output queue full" > > > messages, but as I repeated the bind/unbind sequences the prints per bind/unbind > > > iteration increased in number. > > > > > > Anyhow, on Friday evening/week-end I will continue digging and report back with my > > > findings. > > Huh, after changing some of the hid-picolcd data in order to have less racy > coupling between hid and framebuffer I'm now dying way too often in _mmx_memcpy > and most of the time I don't get a (complete) trace... There was a similar problem reported recently. It turned out to be caused by a __devinitconst annotation attached to a usb_device_id table. If there are any __devinit* annotations in the hid-picolcd driver, you should see if removing them helps. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
