[ofa-general] Re: mlx4 violating radix tree API locking rules?

[Michael S. Tsirkin]

> Quoting Roland Dreier <rdreier at cisco.com>:
> Subject: Re: mlx4 violating radix tree API locking rules?
> 
> By the way, in the past we've gotten push-back against using RCU in
> dual GPL/BSD code.

I don't know what official Mellanox position is on this.
I think that in this case it's OK, simply because 
RCU here is just a requirement from radix tree code, not
from mlx4 itself, so anyone who wants to use this code under BSD license,
can just implement radix tree in a way
that does not require RCU, and then rip out RCU calls.

> I have no problem relicensing mlx4 to GPL-only and
> then sticking in the rcu_read_lock() stuff to handle this I guess.

I don't see how that would help.

BTW I looked for BSD code in kernel today that uses RCU:
$grep -i RCU `grep  -l 'source and binary forms' . -rI
after manually filtering out words such as circular, gave me:
./net/sunrpc/auth_gss/auth_gss.c
./fs/nfs/nfs4proc.c
./drivers/infiniband/hw/ipath/ipath_verbs_mcast.c


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MST