As I work on the in-kernel LLDP prototype, I wanted to be sure about
this -- after calling dls_open() and registering my rx callback, if I
call dls_unbind() or dls_close(), can I be sure that once either
returns, DLS will not be in the middle of invoking my registered
callback? Or to restate it slightly differently, if the registered rx
callback is running on another core, dls_{unbind,close} will wait
until the callback returns before itself returning? I think it does
this presently, though I need to wade through the code a bit more to
be sure, but even then I want to be sure this is defined behavior.