Re: [PATCH] pinctrl-intel: Fix NULL pointer dereference

[Böszörményi Zoltán]

On 2021. 10. 01. 20:11, Andy Shevchenko wrote:
> On Tue, Sep 21, 2021 at 07:07:17AM +0200, Böszörményi Zoltán wrote:
> > On 2021. 09. 20. 18:00, Andy Shevchenko wrote:
> > > On Mon, Sep 20, 2021 at 4:00 PM <zboszor@xxxxx> wrote:
> > > > On an Elkhart Lake based POS hardware prototype, I got this Oops:
> ...
>
> > > > It's probably a firmware bug, so be overly protective:
> > > Patch is simply wrong. While Oops will be gone, the driver won't work correctly.
> > Of course. But a driver that gives up is better than a
> > crashing kernel which results in udevd and "udevadm settle"
> > stalling forever on it. systemd waits about 6 minutes before
> > continuing the boot process that involves these two services
> > timing out and this also prevents powering the computer down.
> Hiding real bugs is not a good strategy. What you may do is blacklisting it.

I got a better solution.

> > > Yes, it's either a firmware bug or the driver is outdated (depends
> > > from which side you look at this issue).
> > >
> > > I have heard that new firmware is on its way to the customers, but I
> > > have no more information right now.
> > Thanks, good to know.
> >
> > I also reported it to the manufacturer, I hope to receive
> > a response from them soon.

They responded with a kernel patch, switching the elkhartlake
pinctrl driver to probe the hardware via HID and this allowed
the driver to initialize.

> > The kernel reports other firmware bugs for this
> > Celeron J6412 based machine.
> Yeah...