RE: [Intel-gfx] [PATCH] drm/i915: Remove unused IRQ chip data of HDMI LPE audio

From: Thomas Gleixner
Date: Wed Dec 13 2017 - 06:36:37 EST


On Wed, 13 Dec 2017, Anand, Jerome wrote:
> > -----Original Message-----
> > From: Thomas Gleixner [mailto:tglx@xxxxxxxxxxxxx]
> > Sent: Tuesday, December 12, 2017 10:37 PM
> > To: Anand, Jerome <jerome.anand@xxxxxxxxx>
> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>; Chen, Augustine
> > <augustine.chen@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; alsa-devel@alsa-
> > project.org; Bossart, Pierre-louis <pierre-louis.bossart@xxxxxxxxx>;
> > tiwai@xxxxxxx; Ingo Molnar <mingo@xxxxxxxxxx>; H. Peter Anvin
> > <hpa@xxxxxxxxx>; Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>; Juergen Gross
> > <jgross@xxxxxxxx>; Dou Liyang <douly.fnst@xxxxxxxxxxxxxx>; linux-
> > kernel@xxxxxxxxxxxxxxx
> > Subject: RE: [Intel-gfx] [PATCH] drm/i915: Remove unused IRQ chip data of
> > HDMI LPE audio

Can you please fix your mail client NOT to replicate the full mail
header. That's just annoying.

> > On Mon, 11 Dec 2017, Anand, Jerome wrote:
> > > > On Fri, 8 Dec 2017, Ville Syrjälä wrote:
> > > >
> > > > > On Fri, Dec 08, 2017 at 05:33:23PM +0800, Augustine.Chen wrote:
> > > > > > The chip data of HDMI LPE audio is set to drm_i915_private which
> > > > > > is not consistent with the expectation by x86 APIC driver.
> > > > >
> > > > > Hmm. Why is the apic code looking at data for an irq chip it
> > > > > hasn't created?
> > > > >
> > >
> > > apic code expects an irq domain to be place as generic approach.
> >
> > APIC code does not even see that interrupt at all. It's completely disconnected.
> >
>
> That's the problem - APIC just converts the chip data to its internal
> format and fails.

How does APIC code end up to touch that interrupt at all? Call stack please.

And please enable CONFIG_GENERIC_IRQ_DEBUGFS and provide the output of

cat /sys/kernel/debug/irq/irqs/$N

where N is the interrupt number of that thing.

Thanks,

tglx