[*] DF-0103: target pid=850; 3 callers racing ktrace(KTROP_SET/CLEAR) for 30s...
[guest panicked ~seconds into the run; ssh session died]
panic: assertion "tracenode->kn_refs > 0" failed in ktrdestroy at /usr/src/sys/kern/kern_ktrace.c:481
Trace:
ktrdestroy()  at ktrdestroy+0x89
ktrdestroy()  at ktrdestroy+0x89
ktrops()      at ktrops+0x65
sys_ktrace()  at sys_ktrace+0xe0
Stopped at Debugger+0x7c
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