Re: [PATCH v2 1/1] mfd: intel-lpss: Fix too early PM enablement in the ACPI ->probe()

From: Andy Shevchenko
Date: Mon Nov 15 2021 - 05:36:29 EST


On Tue, Nov 02, 2021 at 05:42:35AM +0000, Aditya Garg wrote:
> > On 02-Nov-2021, at 12:30 AM, Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:

> > The runtime PM callback may be called as soon as the runtime PM facility
> > is enabled and activated. It means that ->suspend() may be called before
> > we finish probing the device in the ACPI case. Hence, NULL pointer
> > dereference:
> >
> > intel-lpss INT34BA:00: IRQ index 0 not found
> > BUG: kernel NULL pointer dereference, address: 0000000000000030
> > ...
> > Workqueue: pm pm_runtime_work
> > RIP: 0010:intel_lpss_suspend+0xb/0x40 [intel_lpss]
> >
> > To fix this, first try to register the device and only after that enable
> > runtime PM facility.
> >
> > Fixes: 4b45efe85263 ("mfd: Add support for Intel Sunrisepoint LPSS devices")
> > Reported-by: Orlando Chamberlain <redecorating@xxxxxxxxxxxxxx>
> > Reported-by: Aditya Garg <gargaditya08@xxxxxxxx>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > Tested-by: Aditya Garg <gargaditya08@xxxxxxxx>
> > ---
> > v2: added tag (Aditya), returned 0 explicitly at the end of ->probe()

> It works

Thanks for testing again!

Lee, can we have this as a fix material for v5.16-rcX?

--
With Best Regards,
Andy Shevchenko