Re: [PATCH 07/17] net: convert sock.sk_refcnt from atomic_t to refcount_t

From: Kees Cook <redacted>
Date: Thu, 16 Mar 2017 11:38:25 -0600

I am, of course, biased, but I think the evidence of actual
refcounting attacks outweighs the theoretical performance cost of
these changes.

This is not theoretical at all.

We count the nanoseconds that every packet takes to get processed and
you are adding quite a bit.

I understand your point of view, but this is knowingly going to add
performance regressions to the networking code.