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.
In the case of not enabling CONFIG_CPUMASK_OFFSTACK, this would cause kernel panic while doing CPU hotplug.
And why so? Surely not because you set irq_chip_data. That's really no explanation at all.
Ideally, I feel there needs to be an irq domain for mapping the irq numbers with hwirq. It is not created as part of the hdmi lpe audio bridge. Since the logic to mask/unmask lpe audio interrupts is removed, there is no need of the Chip data or creation of the domain now.
That still does not explain why this is broken with CONFIG_CPUMASK_OFFSTACK=n and cpu hotplug.
Thanks,
tglx