nvme tcp receive errors

[Keith Busch]

Sagi,

Just wanted to give you an update on where we're at with this.

All tests run with your earlier patch removing the inline dispatch from
nvme_tcp_queue_request() are successful. At this point, I am leaning to
remove that optimization from mainline.

I added additional tracing to see what is going on, but we eventually
hit a memory issue after some hours of runtime. I've never seen an issue
like this before, It triggers in nvme_tcp_advance_req() when tracing the
rq->tag and req->data_sent:

  WARNING: CPU: 1 PID: 3428 at arch/x86/include/asm/kfence.h:44 kfence_protect_page+0x33/0xa0

I think the above is a distraction, but I can provide the full stack
trace and patch adding the tracepoing if you think it's helpful.