Re: [PATCH v2 2/7] irqchip/ls-scfg-msi: Fix MSI affinity handling

[Alexandre Belloni]

On 22/06/2018 10:52:49+0100, Marc Zyngier wrote:
> The ls-scfs-msi driver is not dealing with the effective affinity
> as it should. Let's fix that, and make it clear that the effective
> affinity is restricted to a single CPU. Also prevent the driver from
> messing with the internals of the affinity setting infrastructure.
> 
> Reported-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>

Tested-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>

> ---
>  drivers/irqchip/irq-ls-scfg-msi.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-ls-scfg-msi.c b/drivers/irqchip/irq-ls-scfg-msi.c
> index 1ec3bfe56693..c671b3212010 100644
> --- a/drivers/irqchip/irq-ls-scfg-msi.c
> +++ b/drivers/irqchip/irq-ls-scfg-msi.c
> @@ -93,8 +93,12 @@ static void ls_scfg_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
>  	msg->address_lo = lower_32_bits(msi_data->msiir_addr);
>  	msg->data = data->hwirq;
>  
> -	if (msi_affinity_flag)
> -		msg->data |= cpumask_first(data->common->affinity);
> +	if (msi_affinity_flag) {
> +		const struct cpumask *mask;
> +
> +		mask = irq_data_get_effective_affinity_mask(data);
> +		msg->data |= cpumask_first(mask);
> +	}
>  
>  	iommu_dma_map_msi_msg(data->irq, msg);
>  }
> @@ -121,7 +125,7 @@ static int ls_scfg_msi_set_affinity(struct irq_data *irq_data,
>  		return -EINVAL;
>  	}
>  
> -	cpumask_copy(irq_data->common->affinity, mask);
> +	irq_data_update_effective_affinity(irq_data, cpumask_of(cpu));
>  
>  	return IRQ_SET_MASK_OK;
>  }
> -- 
> 2.17.1
> 

-- 
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com