Re: [PATCH v1 1/4] arm/time: Use static irqaction

[Julien Grall <julien@xxxxxxx>]

Hi Mykyta,

On 18/09/2025 13:16, Mykyta Poturai wrote:
> When stopping a core deinit_timer_interrupt 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>
> ---
>   xen/arch/arm/time.c | 20 ++++++++++++++++----
>   1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
> index e74d30d258..6f215de210 100644
> --- a/xen/arch/arm/time.c
> +++ b/xen/arch/arm/time.c
> @@ -303,6 +303,20 @@ static void check_timer_irq_cfg(unsigned int irq, const 
> char *which)
>              "WARNING: %s-timer IRQ%u is not level triggered.\n", which, irq);
>   }
>   
> +static struct irqaction __read_mostly irq_hyp = {
> +    .name = "hyptimer",
> +    .handler = htimer_interrupt,
> +    .dev_id = NULL,
> +    .free_on_release = 0,
> +};
> +
> +static struct irqaction __read_mostly irq_virt = {
> +    .name = "virtimer",
> +    .handler = vtimer_interrupt,
> +    .dev_id = NULL,
> +    .free_on_release = 0,
> +};
setup_irq() will update the field "next" in irqaction. So we need one 
instance per call. Effectively, this means one per CPU. Therefore, we 
want to use DEFINE_PER_CPU. This applies to the rest of the series.
Cheers,

--
Julien Grall