Re: [PATCH 2/2] irqchip/armada-370-xp: Do not allow mapping IRQ 0 and 1

From: Marc Zyngier
Date: Fri May 06 2022 - 07:22:40 EST


On Mon, 25 Apr 2022 12:37:06 +0100,
Pali Rohár <pali@xxxxxxxxxx> wrote:
>
> IRQs 0 and 1 cannot be mapped, they are handled internally by this driver
> and this driver does not call generic_handle_domain_irq() for these IRQs.
> So do not allow mapping these IRQs and correctly propagate error from the
> .irq_map callback.
>
> Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> drivers/irqchip/irq-armada-370-xp.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
> index 1120084cba09..ebd76ea1c69b 100644
> --- a/drivers/irqchip/irq-armada-370-xp.c
> +++ b/drivers/irqchip/irq-armada-370-xp.c
> @@ -546,6 +546,10 @@ static struct irq_chip armada_370_xp_irq_chip = {
> static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
> unsigned int virq, irq_hw_number_t hw)
> {
> + /* IRQs 0 and 1 cannot be mapped, they are handled internally */
> + if (hw <= 1)
> + return -EINVAL;
> +
> armada_370_xp_irq_mask(irq_get_irq_data(virq));
> if (!is_percpu_irq(hw))
> writel(hw, per_cpu_int_base +
> --
> 2.20.1
>
>

Given that this is completely academic and obviously doesn't affect
anyone, I have removed the Cc: stable from the patch when applying it.

M.

--
Without deviation from the norm, progress is not possible.