Re: [PATCH] [RFC] genirq/cpuhotplug, PCI/rcar-host: Silence set affinity failed warning

[Thomas Gleixner <tglx@linutronix.de>]

On Mon, Jul 08 2024 at 13:55, Marek Vasut wrote:
> On 7/7/24 8:47 PM, Thomas Gleixner wrote:
>> Why does the irq_chip in question have an irq_set_affinity() callback in
>> the first place?
> I believe originally (at least that's what's being discussed in the 
> linked threads) it was because the irqchip code didn't check whether 
> .irq_set_affinity was not NULL at all, so if it was missing, there would 
> be NULL pointer dereference.
>
> Now this is checked and irq_do_set_affinity() returns -EINVAL, which 
> triggers the warning that is being silenced by this patch.
>
> If you think this is better, I can:
> - Tweak the cpuhotplug.c code to do some
>    if (chip && !chip->irq_set_affinity) return false;

It does already:

migrate_one_irq()
  if (chip && !chip->irq_set_affinity)
    return false;

Right at the top.

> - Remove all the .irq_set_affinity implementations from PCI drivers
>    which only return -EINVAL
>
> Would that be better ?

I think so.

Thanks,

        tglx