Re: [PATCH] x86: dovetail: Use appropriate EOI on error interrupts

[Philippe Gerum <rpm@xenomai.org>]

Jan Kiszka <jan.kiszka@siemens.com> writes:

> From: Jan Kiszka <jan.kiszka@siemens.com>
>
> Just like for the non-pipelined spurious interrupt, we need to invoke
> the non-pipelined __apic_eoi while handling error interrupts. Otherwise,
> the local APIC will stop receiving further interrupts, and the system
> will stall.
>
> Given that it takes very special conditions to actually trigger an error
> interrupt, this issue was very likely not relevant for most deployments.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  arch/x86/kernel/apic/apic.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> index 1cd5f59f7962f..278e28c5290d3 100644
> --- a/arch/x86/kernel/apic/apic.c
> +++ b/arch/x86/kernel/apic/apic.c
> @@ -2217,7 +2217,7 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_error_interrupt)
>  	if (lapic_get_maxlvt() > 3)	/* Due to the Pentium erratum 3AP. */
>  		apic_write(APIC_ESR, 0);
>  	v = apic_read(APIC_ESR);
> -	apic_eoi();
> +	__apic_eoi();
>  	atomic_inc(&irq_err_count);
>  
>  	apic_pr_debug("APIC error on CPU%d: %02x", smp_processor_id(), v);

Merged (v6.1.y [__ack_APIC_irq], v6.12.y, v6.15 and upcoming v6.16), thanks.

(short log fixed up slightly to ease commit identification on my end)

-- 
Philippe.