Re: [PATCH v6 21/24] arm64: Handle serror in NMI context

From: Catalin Marinas
Date: Tue Dec 04 2018 - 13:09:25 EST


On Mon, Nov 12, 2018 at 11:57:12AM +0000, Julien Thierry wrote:
> diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
> index 5f4d9ac..66344cd 100644
> --- a/arch/arm64/kernel/traps.c
> +++ b/arch/arm64/kernel/traps.c
> @@ -897,13 +897,17 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
>
> asmlinkage void do_serror(struct pt_regs *regs, unsigned int esr)
> {
> - nmi_enter();
> + const bool was_in_nmi = in_nmi();
> +
> + if (!was_in_nmi)
> + nmi_enter();
>
> /* non-RAS errors are not containable */
> if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr))
> arm64_serror_panic(regs, esr);
>
> - nmi_exit();
> + if (!was_in_nmi)
> + nmi_exit();
> }

Do we actually need nmi_enter/exit in the outer do_serror() function?
Could we just move it to arm64_serror_panic()?

--
Catalin