Re: [PATCH v3 4/8] blk-mp: introduce blk_mq_hctx_map_queues

[Daniel Wagner]

On Tue, Nov 12, 2024 at 02:58:43PM +0100, Greg Kroah-Hartman wrote:
> > +void blk_mq_hctx_map_queues(struct blk_mq_queue_map *qmap,
> > +                       struct device *dev, unsigned int offset)
> > +
> > +{
> > +   const struct cpumask *mask;
> > +   unsigned int queue, cpu;
> > +
> > +   if (!dev->bus->irq_get_affinity)
> > +           goto fallback;
> 
> I think this is better than hard-coding it, but are you sure that the
> bus will always be bound to the device here so that you have a valid
> bus-> pointer?

No, I just assumed the bus pointer is always valid. If it is possible to
have a device without a bus, than I'll better extend the condition to

        if (!dev->bus || !dev->bus->irq_get_affinity)
                goto fallback;