Re: [PATCH v3 2/5] arm/gic: Use static irqaction

[Mykola Kvach <xakep.amatop@xxxxxxxxx>]

Hi Mykyta,

On Fri, Oct 10, 2025 at 12:22 PM Mykyta Poturai <Mykyta_Poturai@xxxxxxxx> wrote:
>
> When stopping a core cpu_gic_callback is called in non-alloc
> context, which causes xfree in release_irq to fail an assert.
>
> To fix this, switch to a statically allocated irqaction that does not
> need to be freed in release_irq.
>
> Signed-off-by: Mykyta Poturai <mykyta_poturai@xxxxxxxx>
>
> v2->v3:
> * no changes
>
> v1->v2:
> * use percpu actions
> ---
>  xen/arch/arm/gic.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
> index 260ee64cca..ed6853bb32 100644
> --- a/xen/arch/arm/gic.c
> +++ b/xen/arch/arm/gic.c
> @@ -386,10 +386,17 @@ void gic_dump_info(struct vcpu *v)
>      gic_hw_ops->dump_state(v);
>  }
>
> +DEFINE_PER_CPU_READ_MOSTLY(struct irqaction, irq_maintenance);

Scope nit (MISRA C:2012 R8.8):
if irq_maintenance is only used in this TU, give it internal linkage.

> +
>  void init_maintenance_interrupt(void)
>  {
> -    request_irq(gic_hw_ops->info->maintenance_irq, 0, maintenance_interrupt,
> -                "irq-maintenance", NULL);
> +    struct irqaction *maintenance = &this_cpu(irq_maintenance);
> +
> +    maintenance->name = "irq-maintenance";
> +    maintenance->handler = maintenance_interrupt;
> +    maintenance->dev_id = NULL;
> +    maintenance->free_on_release = 0;
> +    setup_irq(gic_hw_ops->info->maintenance_irq, 0, maintenance);
>  }
>
>  int gic_make_hwdom_dt_node(const struct domain *d,
> --
> 2.34.1
>

Reviewed-by: Mykola Kvach <mykola_kvach@xxxxxxxx>

Best regards,
Mykola