Re: [PATCH 04/10] xen/arm/irq: allow assignment/releasing of eSPI interrupts

[Julien Grall <julien@xxxxxxx>]

Hi,

On 24/07/2025 15:57, Leonid Komarianskyi wrote:
> The current checks don't allow us to assign or release interrupts
> with INTID greater than 1024. This patch adds an additional condition
> to check whether the IRQ number is in the eSPI range and allows it to
> be assigned to Xen and domains if it is.
> > Signed-off-by: Leonid Komarianskyi <leonid_komarianskyi@xxxxxxxx>
> ---
>   xen/arch/arm/irq.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
> index 3f68257fde..8c47eeb7c3 100644
> --- a/xen/arch/arm/irq.c
> +++ b/xen/arch/arm/irq.c
> @@ -444,8 +444,8 @@ err:
>   
>   bool is_assignable_irq(unsigned int irq)
>   {
> -    /* For now, we can only route SPIs to the guest */
> -    return (irq >= NR_LOCAL_IRQS) && (irq < gic_number_lines());
> +    /* For now, we can only route SPIs and eSPIs to the guest */
> +    return (((irq >= NR_LOCAL_IRQS) && (irq < gic_number_lines())) || 
> is_espi(irq));
>   }
is_assignable_irq() is called by route_irq_to_guest() which first check 
'virq >= vgic_num_irqs()'. AFAICT, if we apply only up to this patch, 
'virq' would still require to < 1024. So ...

>   be
>   /*
> @@ -589,8 +589,8 @@ int release_guest_irq(struct domain *d, unsigned int virq)
>       unsigned long flags;
>       int ret;
>   
> -    /* Only SPIs are supported */
> -    if ( virq < NR_LOCAL_IRQS || virq >= vgic_num_irqs(d) )
> +    /* Only SPIs and eSPIs are supported */
> +    if ( (virq < NR_LOCAL_IRQS || virq >= vgic_num_irqs(d)) && !is_espi(virq) )
... I don't quite understand why this (yet?) need a change. Can you clarify?

>           return -EINVAL;
>   
>       desc = vgic_get_hw_irq_desc(d, NULL, virq);
Cheers,

--
Julien Grall