Re: [PATCH 2/2] riscv: stack: Fixup independent softirq stack for CONFIG_FRAME_POINTER=n

From: Greg KH
Date: Sat Jul 15 2023 - 10:19:43 EST


On Sat, Jul 15, 2023 at 09:45:52AM -0400, guoren@xxxxxxxxxx wrote:
> From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
>
> The independent softirq stack uses s0 to save & restore sp, but s0 would
> be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list
> to fix the problem.
>
> Fixes: dd69d07a5a6c ("riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK")
> Reported-by: Zhangjin Wu <falcon@xxxxxxxxxxx>
> Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Guo Ren <guoren@xxxxxxxxxx>
> ---
> arch/riscv/kernel/irq.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
> index d0577cc6a081..0b58720109db 100644
> --- a/arch/riscv/kernel/irq.c
> +++ b/arch/riscv/kernel/irq.c
> @@ -83,7 +83,7 @@ void do_softirq_own_stack(void)
> :
> : [sp] "r" (sp)
> : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7",
> - "t0", "t1", "t2", "t3", "t4", "t5", "t6",
> + "t0", "t1", "t2", "t3", "t4", "t5", "t6", "s0",
> "memory");
> } else
> #endif
> --
> 2.36.1
>

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>