The following reply was made to PR kern/53265; it has been noted by GNATS.
From: Andreas Gustafsson <gson%gson.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc:
Subject: Re: kern/53265: panic in bnx_detach() on shutdown
Date: Mon, 7 May 2018 17:42:32 +0300
  Masanobu SAITOH wrote:
  > How often does it panic on shutdown?
  
  It has only happened once.
  
  > Could you test the following patch
  > to verify the problem is fixed?
  
  I tested the patch and was able to shut down the system without a
  panic, and did not notice any other problems, either. Since I have
  also been able to shut it down without a panic many times without the
  patch, this isn't conclusive proof that the problem is fixed