Re: [RFC] #MC mess

From: Peter Zijlstra
Date: Tue Feb 18 2020 - 16:53:36 EST


On Tue, Feb 18, 2020 at 10:49:04PM +0100, Peter Zijlstra wrote:
> diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
> index da0af631ded5..146332764673 100644
> --- a/include/linux/hardirq.h
> +++ b/include/linux/hardirq.h
> @@ -71,7 +71,7 @@ extern void irq_exit(void);
> printk_nmi_enter(); \
> lockdep_off(); \
> ftrace_nmi_enter(); \
> - BUG_ON(in_nmi()); \
> + BUG_ON(in_nmi() == 0xf); \

That wants to be:

BUG_ON(in_nmi() == NMI_MASK); \

> preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET); \
> rcu_nmi_enter(); \
> trace_hardirq_enter(); \