On Jul 6, 2018, at 3:29 PM, Toke Høiland-Jørgensen <toke@toke.dk> wrote:

Thanks for investigating! I'll take a look later. The fact that it
happens with sfq as well means it's probably not cake-specific, though,
so I don't think we should hold off on the upstream submission until
we've figured it out. Using leaf qdiscs with netem has been dodgy for a
while IIRC...

Yeah, I’m seeing now that the lockup does _not_ occur when netem is not used and cake is the root.

I’m also satisfied for now that this shouldn’t hold us up. However, what I’ll also want to try next is netem on a separate veth device from cake. I believe Dave’s veth testing earlier was using three namespaces / veth devices, maybe for this reason(?)

Nice work Jon on the lockup bug also- it’s nice seeing this come together… :)

Pete