Hi, On Wed, Oct 18, 2023 at 4:41 AM Hayes Wang <hayeswang@xxxxxxxxxxx> wrote: > > > In any case, we haven't actually seen hardware that fails like this. > > We've seen failure rates that are much much lower and we can imagine > > failure rates that are 100% if we're got really broken hardware. Do > > you think cases where failure rates are middle-of-the-road are likely? > > That is my question, too. > I don't know if something would cause the situation, either. > This is out of my knowledge. > I am waiting for the professional answers, too. > > A lot of reasons may cause the fail of the control transfer. > I don't have all of the real situation to analyze them. > Therefore, what I could do is to assume different situations. > You could say my hypotheses are unreasonable. > However, I have to tell you what I worry. Of course! ...and I appreciate your thoughts on the topic. The more eyes on a patch the more problems that are caught. Unless someone disagrees, I think we at least have ideas for how this could be addressed if it comes up. Also unless someone disagrees, I think that if this does come up in some situation it won't be a catastrophe. Given how things look now, I'm going to plan to send a new version of the patch later today. Though the commit message is long, I'll add a little more to talk about this case and point to ideas for how it could be solved if it comes up. > > I would also say that nothing we can do can perfectly handle faulty > > hardware. If we're imagining theoretical hardware, we could imagine > > theoretical hardware that de-enumerated itself and re-enumerated > > itself every half second because the firmware on the device crashed or > > some regulator kept dropping. This faulty hardware would also cause an > > infinite loop of de-enumeration and re-enumeration, right? > > > > Presumably if we get into either case, the user will realize that the > > hardware isn't working and will unplug it from the system. While the > > Some of our devices are onboard. That is, they couldn't be unplugged. > That is why I have to consider a lot of situations. Good point! I think even with onboard devices we could already have preexisting conditions that could cause an unbind/rebind loop. This would be a new condition, of course. -Doug
