Hi Tomas, > > > > > A Bluetooth device experiencing hardware failure may issue > > > > > a HARDWARE_ERROR hci event. The reaction to this event is device > > > > > reset flow implemented in following sequence. > > > > > > > > > > 1. Notify: HCI_DEV_DOWN > > > > > 2. Reinitialize internal structures. > > > > > 3. Call driver flush function > > > > > 4. Send HCI reset request to the device. > > > > > 5. Send HCI init sequence reset to the device. > > > > > 6. Notify HCI_DEV_UP. > > > > > > > > I prefer if we create a generic per controller workqueue first before > > > > having a workqueue for every task. Something similar to what the > > > > mac80211 layer offers right now. > > > > > > That would be good approach but we are using default kernel workqueue in > > this solution so there is no workqueue for every task. > > > I'm not sure if this effort should block this patch. > > > > I have an initial patch that I have to dig out. It is actually not that > > complicated. And I would prefer to get that one first before we apply > > this patch. > > Okay, I can test this particular flow with your patch if you send it to me. I pushed the per controller workqueue patch into bluetooth-testing.git tree. Please adapt your patch to that and test it. > > The reason why I really wanna solve this is because of potential race > > conditions between the workqueue and a device removal. I have a bad > > feeling that even with the current sysfs workqueue we have a race > > condition hiding somewhere. So if going forward we have to shift more > > and more code into workqueues we need a single point where this can be > > fixed. > > Understood. > > In that context I would need to do some more instrumentation to test this kind of race for this feature. I could be very well that we are protected against such a race. However with moving from tasklet into workqueue I am always cautious. And I wanna make sure that we keep the complexity simple. I want one place to fix if it breaks and not twenty. Regards Marcel -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
