On Thu, 16 Nov 2017 14:03:02 -0600 Brian King <brking@xxxxxxxxxxxxxxxxxx> wrote: > I did think about changing the powerpc definition of read_barrier_depends, > but after reading up on that barrier, decided it was not the correct barrier > to be used in this context. Here is some good historical background on > read_barrier_depends that I found, along with an example. > > https://lwn.net/Articles/5159/ > > Since there is no data-dependency in the code in question here, I think > the smp_rmb is the proper barrier to use. Hey Brian, thanks for the explanation, I'll agree with you and Alex that the smb_rmb replacement is okay. Does your test still pass without the ->skb NULLs?