Re: [bug, bisected] pfifo_fast causes packet reordering

[Jakob Unterwurzacher]

On 21.03.18 19:43, John Fastabend wrote:
> Thats my theory at least. Are you able to test a patch if I generate
> one to fix this?

Yes, no problem.

I just tested with the flag change you suggested (see below, I had to 
keep TCQ_F_CPUSTATS to prevent a crash) and I have NOT seen OOO so far.

Thanks,
Jakob


diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 190570f21b20..51b68ef4977b 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -792,7 +792,7 @@ struct Qdisc_ops pfifo_fast_ops __read_mostly = {
        .dump           =       pfifo_fast_dump,
        .change_tx_queue_len =  pfifo_fast_change_tx_queue_len,
        .owner          =       THIS_MODULE,
-       .static_flags   =       TCQ_F_NOLOCK | TCQ_F_CPUSTATS,
+       .static_flags   =       TCQ_F_CPUSTATS,
 };
 EXPORT_SYMBOL(pfifo_fast_ops);