On Wed, Nov 03, 2021 at 01:35:23PM +0100, Emil Renner Berthing wrote: > On Wed, 3 Nov 2021 at 10:13, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > > On Tue, Nov 2, 2021 at 10:35 PM Emil Renner Berthing <kernel@xxxxxxxx> wrote: > > > On Tue, 2 Nov 2021 at 21:02, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > > > > On Tue, Nov 2, 2021 at 6:50 PM Emil Renner Berthing <kernel@xxxxxxxx> wrote: ... > > > > > + irq_set_handler_locked(d, handle_bad_irq); > > > > > > > > Why? You have it already in ->probe(), what's the point? > > > > > > So last time you asked about this, I explained a situation where > > > userspace first grabs a GPIO, set the interrupt to edge triggered, and > > > then later loads a driver that requests an unsupported IRQ type. > > > > I didn't get this scenario. Is it real? > > No, it's totally made up, but I mean we even have tools like fuzzing > to help us find bugs that would never happen in real use cases. > > > > Then > > > I'd like to set the handler back to handle_bad_irq so we don't get > > > weird interrupts, but maybe now you know a reason why that doesn't > > > matter or can't happen? > > > > In ->probe() you set _default_ handler to bad(), what do you mean by > > 'set the handler back to bad()'? How is it otherwise if you free an > > interrupt? > > It might not be, but when not sure I thought it better to error on the > safe side. With a dead code? I do not believe there is an issue since. like I said, there are plenty drivers that don't do what you are suggesting here --> 99.99% you added a dead code. > > So, please elaborate with call traces what the scenario / use case you > > are talking about. If it's true what you are saying, we have a > > situation (plenty of GPIO drivers don't do what you are suggesting > > here). -- With Best Regards, Andy Shevchenko
