Re: common_interrupt: No irq handler for vector

[Thomas Gleixner]

On Fri, Dec 11 2020 at 13:41, Shuah Khan wrote:

> I am debugging __common_interrupt: 1.55 No irq handler for vector
> messages and noticed comments and code don't agree:

I bet that's on an AMD system with broken AGESA BIOS.... Good luck
debugging it :) BIOS updates are on the way so I'm told.

> arch/x86/kernel/apic/msi.c: msi_set_affinity() says:
>
>
>   * If the vector is in use then the installed device handler will
>   * denote it as spurious which is no harm as this is a rare event
>   * and interrupt handlers have to cope with spurious interrupts
>   * anyway. If the vector is unused, then it is marked so it won't
>   * trigger the 'No irq handler for vector' warning in
>   * common_interrupt().
>
> common_interrupt() prints message if vector is unused: VECTOR_UNUSED
>
> ack_APIC_irq();
>
> if (desc == VECTOR_UNUSED) {
>      pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n",
>                            __func__, smp_processor_id(), vector);
> }
>
> Something wrong here?

No. It's perfectly correct in the MSI code. See further down.

	if (IS_ERR_OR_NULL(this_cpu_read(vector_irq[cfg->vector])))
		this_cpu_write(vector_irq[cfg->vector], VECTOR_RETRIGGERED);

Thanks,

        tglx