deadman panic due to mutex lock contention inside lookuppnatcred()
Review Request #664 - Created Sept. 21, 2017 and updated
User application doing fstatat() on entries in the same folder can induce a deadman panic. The fix is quite simple - if there's startvp, release the process lock and then do VN_HOLD().
Using the test program attached to the bug report, the panic was not reproducible. In addition, we also ran our in-house load testing, which caused server crashes frequently.