RE: [PATCH v2] block: fix rdma queue mapping

Steve Wise
2018-10-23T21:24:19Z

> >> Christoph, Sagi: it seems you think /proc/irq/$IRP/smp_affinity
> >> shouldn't be allowed if drivers support managed affinity. Is that correct?
> >
> > Not just shouldn't, but simply can't.
> >
> >> But as it stands, things are just plain borked if an rdma driver
> >> supports ib_get_vector_affinity() yet the admin changes the affinity via
> >> /proc...
> >
> > I think we need to fix ib_get_vector_affinity to not return anything
> > if the device doesn't use managed irq affinity.
>
> Steve, does iw_cxgb4 use managed affinity?
>
> I'll send a patch for mlx5 to simply not return anything as managed
> affinity is not something that the maintainers want to do.

I'm beginning to think I don't know what "managed affinity" actually is. Currently iw_cxgb4 doesn't support ib_get_vector_affinity(). I have a patch for it, but ran into this whole issue with nvme failing if someone changes the affinity map via /proc.

Steve.