Re: Failed IRQ assignment for INT0002 on Braswell

From: Oleksandr Natalenko
Date: Wed Nov 22 2017 - 07:48:23 EST


Hi, Hans.

On stÅeda 22. listopadu 2017 11:48:50 CET Hans de Goede wrote:
> /* snip */
> This should be fixed by:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/ke
> rnel/irq?id=382bd4de61827dbaaf5fb4fb7b1f4be4a86505e7
>
> Which is in 4.13, but the trigger-type does not seem to be the problem in
> your case, the problem likely is the ONESHOT flag:
>
> #define IRQF_ONESHOT 0x00002000
>
> Which appears to be set in the flags for the acpi irq handler:
> > kernel: genirq: Flags mismatch irq 9. 00010084 (INT0002) vs. 00002080
> > (acpi)
> But that irq is requested here:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/driv
> ers/acpi/osl.c#n570
>
>
>
> if (request_irq(irq, acpi_irq, IRQF_SHARED, "acpi", acpi_irq)) {
> printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq);
> ...
>
> And IRQF_ONESHOT is not passed, so I do not understand where the 00002000 in
> the acpi irq handler flags is coming from ...

Well, looks like I know where this flag comes from. I boot this machine with
"threadirqs", and IRQF_ONESHOT description says:

===
52 * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler
finished.
53 * Used by threaded interrupts which need to keep the
54 * irq line disabled until the threaded handler has been
run.
===

If I boot the machine without "threadirqs", looks like the device is set up
okay. The only message I get in the kernel log is:

===
kernel: acpi INT0002:00: Device [GPED] is in always present list
===

Grepping for IRQ 9:

===
kernel: ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
kernel: ACPI: IRQ9 used by override.
===

and 9th interrupt shows this device:

===
9: 0 0 0 0 IO-APIC 9-fasteoi
acpi, INT0002
===

Any idea why "threadirqs" makes this fail?

Thanks.

Regards,
Oleksandr