On Fri, 21 Dec 2007 22:24:28 -0800 Pete Zaitcev <[EMAIL PROTECTED]> wrote:
> On Fri, 21 Dec 2007 00:00:04 -0800, Daniel Walker <[EMAIL PROTECTED]> wrote: > > > I converted the usu_init_notify semaphore to normal mutex usage, and it > > should still prevent the request_module before the init routine is > > complete. Before it acted more like a complete, now the mutex protects > > two distinct section from running at the same time.. > > Let's see. > > > @@ -178,10 +179,7 @@ static int usu_probe_thread(void *arg) > > int rc; > > unsigned long flags; > > > > - /* A completion does not work here because it's counted. */ > > - down(&usu_init_notify); > > - up(&usu_init_notify); > > - > > + mutex_lock(&usu_probe_mutex); > > rc = request_module(bias_names[type]); > > When I tried it, usb-storage would not load with unresolved symbols. > It happens if child (usu_probe_thread) runs ahead of its parent > (usb_usual_init -> usb_register -> usu_probe). It's entirely possible, > depending on your scheduler. afaict Daniel's change will fix that? He releases usu_probe_mutex once the usb_register() has completed and this then allows the usb_probe_thread() to start working. I'm still wondering if that theory has been tested though. > I hate this down-up trick too I'd be worried if you were proud of it ;) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
