Hi, hverkuil wrote:
> > + if (sev->ops && sev->ops->add) { > > + int ret = sev->ops->add(sev); > > + if (ret) { > > + sev->ops = NULL; > > + v4l2_event_unsubscribe(fh, sub); > > + return ret; > > + }The problem here is that the event is basically available for use after the spin_unlock_irqrestore(), but before the sev->ops->add() call. In the past I just 'knew' that the event would never be generated by the control framework until after v4l2_ctrl_add_event was called, but this should be formalized now that these ops are added. I see two options: 1) Have some method to mark the sev as being 'invalid' so functions sending events can skip it (needed as well for your patch 4/6). 2) Document that drivers should never be able to send an event until after the add() callback has succeeded. I am leaning towards option 1 myself. How about leaving sev->elems at 0 until after the add() op succeeds? That's easy to test against and easy to implement.
I agree that option 1 is the best and that leaving sev->elems 0 is a good way to do this. This will be in my next revision of this patch set. Thanks & Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
