Re: [PATCH] arm64: use SOFTIRQ_ON_OWN_STACK for enabling softirq stack

[Will Deacon]

On Mon, Oct 13, 2025 at 01:35:08AM +0000, Ryo Takakura wrote:
> For those architectures with HAVE_SOFTIRQ_ON_OWN_STACK use
> their dedicated softirq stack when !PREEMPT_RT. This condition
> is ensured by SOFTIRQ_ON_OWN_STACK.
> 
> Let arm64 use SOFTIRQ_ON_OWN_STACK as well to select its
> usage of the stack.
> 
> Signed-off-by: Ryo Takakura <ryotkkr98@xxxxxxxxx>
> ---
>  arch/arm64/kernel/irq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
> index c0065a1d77cf..15dedb385b9e 100644
> --- a/arch/arm64/kernel/irq.c
> +++ b/arch/arm64/kernel/irq.c
> @@ -62,7 +62,7 @@ static void __init init_irq_stacks(void)
>  	}
>  }
>  
> -#ifndef CONFIG_PREEMPT_RT
> +#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK
>  static void ____do_softirq(struct pt_regs *regs)
>  {
>  	__do_softirq();

Acked-by: Will Deacon <will@xxxxxxxxxx>

Will