Re: Bug: d0e936adbd22 crashes at boot

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

On Fri, 2021-09-03 at 14:57 -0600, Jens Axboe wrote:
> On 9/3/21 2:41 PM, Jens Axboe wrote:
> > On 9/3/21 12:00 PM, Srinivas Pandruvada wrote:
> > > Hi Axobe,
> > > 
> > > On Fri, 2021-09-03 at 09:00 -0600, Jens Axboe wrote:
> > > > On 9/3/21 8:38 AM, Srinivas Pandruvada wrote:
> > > > > On Fri, 2021-09-03 at 08:15 -0600, Jens Axboe wrote:
> > > > > > On 9/3/21 8:13 AM, Srinivas Pandruvada wrote:
> > > > > > > Hi Axboe,
> > > > > > > 
> > > > > > > Thanks for reporting.
> > > > > > > On Fri, 2021-09-03 at 07:36 -0600, Jens Axboe wrote:
> > > > > > > > Hi,
> > > > > > > > 
> > > > > > > > Booting Linus's tree causes a crash on my laptop, an x1
> > > > > > > > gen9.
> > > > > > > > This
> > > > > > > > was
> > > > > > > > a bit
> > > > > > > > difficult to pin down as it crashes before the display
> > > > > > > > is up,
> > > > > > > > but I
> > > > > > > > managed
> > > > > > > > to narrow it down to:
> > > > > > > > 
> > > > > > > > commit d0e936adbd2250cb03f2e840c6651d18edc22ace
> > > > > > > > Author: Srinivas Pandruvada < 
> > > > > > > > srinivas.pandruvada@linux.intel.com>
> > > > > > > > Date:   Thu Aug 19 19:40:06 2021 -0700
> > > > > > > > 
> > > > > > > >     cpufreq: intel_pstate: Process HWP Guaranteed
> > > > > > > > change
> > > > > > > > notification
> > > > > > > > 
> > > > > > > > which crashes with a NULL pointer deref in
> > > > > > > > notify_hwp_interrupt() -
> > > > > > > > > 
> > > > > > > > queue_delayed_work_on().
> > > > > > > > 
> > > > > > > > Reverting this change makes the laptop boot fine again.
> > > > > > > > 
> > > > > > > Does this change fixes your issue?
> > > > > > 
> > > > > > I would assume so, as it's crashing on cpudata == NULL :-)
> > > > > > 
> > > > > > But why is it NULL? Happy to test patches, but the below
> > > > > > doesn't
> > > > > > look
> > > > > > like
> > > > > > a real fix and more of a work-around.
> > > > > 
> > > 
> > > Please try the attached.
> > 
> > I'll give it a test spin right now. Please do add a Reported-by
> > tag,
> > though. That's always prudent.
> 
> And you can add Tested-by as well, it works for me.

Thanks. I will add both.

-Srinivas
>