Re: infiniband limit of 32 cards per system?

Alex Chiang
2010-01-26T21:38:03Z

* Roland Dreier <rdreier-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org>:
>
> > I'm guessing that it's not just a simple kernel fix though since
> > OFED has to change too, right?
>
> Dunno about OFED. Nothing sane is hard-coding major/minor numbers
> though -- so I think OFED should be OK, asuming there are no crazy
> scripts that bypass udev creating device nodes etc.

Ok.

> I don't think that it's _totally_ trivial in the kernel -- we
> do need to add some code in several places to allocate dynamic
> device numbers when we run out of the static allocation
> (probably best to keep the legacy device numbers for "small" <
> 32 adapter systems, since there may be really small systems
> with static hard-coded /dev etc).

I take it this concern is what prevents us from simply increasing
IB_UVERBS_MAX_DEVICES to 64 or something?

thanks,
/ac