Re: [Patch v7 01/18] ACPI, irq: fix regression casued by 6b9fb7082409

[Pavel Machek <pavel@ucw.cz>]

Hi!

> When IOAPIC is disabled, acpi_gsi_to_irq() should return gsi directly
> instead of calling mp_map_gsi_to_irq() to translate gsi to IRQ by IOAPIC.
> It fixes https://bugzilla.kernel.org/show_bug.cgi?id=84381.
> 
> Reported-by: Thomas Richter <thor@math.tu-berlin.de>
> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
> Cc: rui.zhang@intel.com
> Cc: <stable@vger.kernel.org> # 3.17
> ---
>  arch/x86/kernel/acpi/boot.c |   13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index b436fc735aa4..eceba9d9e116 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -604,14 +604,19 @@ void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
>  
>  int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp)
>  {
> -	int irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC | IOAPIC_MAP_CHECK);
> +	int irq;
>  
> -	if (irq >= 0) {
> +	if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) {
> +		*irqp = gsi;

As you have multiple return points, anyway, I'd do return 0; here

> +	} else {
> +		irq = mp_map_gsi_to_irq(gsi,
> +					IOAPIC_MAP_ALLOC | IOAPIC_MAP_CHECK);
> +		if (irq < 0)
> +			return -1;
>  		*irqp = irq;
> -		return 0;
>  	}

...so that one level of nesting is avoided, and there are no problems
with fiting to 80 colums.

With that,

Acked-by: Pavel Machek <pavel@ucw.cz>

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