I've pushed a bunch of work, please update to the latest master
and continue testing!
No smoking gun but I suspect machine load may be causing m_reclaim()
to get run, which drains various protocol caches. Those caches were
not MPSAFE. The changes address that issue.
If these changes don't fix the problem then compile a fresh kernel
with two options added to your kernel config:
options SOCKBUF_DEBUG
options MBUF_DEBUG
These are fairly invasive options so only compile them in if the
problems have not gone away. Hopefully then we will get a panic
closer to where the actual bad code is instead of well after the
fact.
-Matt