RE: [PATCH 3/3] irqchip/renesas-rzg2l: Add NMI support

[Biju Das]

Hi Thomas,

Thanks for the feedback.

> -----Original Message-----
> From: Thomas Gleixner <tglx@xxxxxxxxxx>
> Sent: 31 March 2026 17:16
> Subject: Re: [PATCH 3/3] irqchip/renesas-rzg2l: Add NMI support
> 
> On Sat, Mar 28 2026 at 10:33, Biju wrote:
> > +static void rzg2l_irqc_nmi_eoi(struct irq_data *d) {
> > +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +	unsigned int hw_irq = irqd_to_hwirq(d);
> > +
> > +	scoped_guard(raw_spinlock, &priv->lock)
> > +		rzg2l_clear_nmi_int(priv, hw_irq);
> 
> Is priv is shared between regular interrupts and the NMI?

Yes.

> 
> If so, then you can't take the lock.

OK.

> 
>     // Some other context (task, interrupt)
>     raw_spinlock(priv->lock);
> 
> --> NMI
> 
>         raw_spinlock(priv->lock);
> 
> --> Livelock.

Will drop the lock as it is not RMW operation.

Cheers,
Biju