Re: kern/55611: panic on shutdown

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/55611; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/55611: panic on shutdown
Date: Sun, 4 Jul 2021 16:44:30 +0000

 On Fri, Aug 28, 2020 at 08:55:00AM +0000, martin%NetBSD.org@localhost wrote:
  > Installed a new kernel, did "shutdown -r now" and it ended like this:
  > 
  > syslogd[993]: Exiting on signal 15
  > [ 954.5799395] panic: kernel diagnostic assertion "sn->sn_opencnt == 0" failed: file "../../../../miscfs/specfs/spec_vnops.c", line 414 
  > [ 954.5999499] cpu1: Begin traceback...
  > [ 954.6099548] 0x1065db40: at vpanic+0x12c
  > [ 954.6199623] 0x1065db70: at kern_assert+0x60
  > [ 954.6299665] 0x1065dbb0: at spec_node_revoke+0x108
  > [ 954.6399731] 0x1065dbd0: at vcache_reclaim+0x664
  > [ 954.6399731] 0x1065dc60: at vgone+0x114
  > [ 954.6399731] 0x1065dc80: at vrevoke+0x114
  > [ 954.6399731] 0x1065dcb0: at genfs_revoke+0x1c
  > [ 954.6800071] 0x1065dcc0: at VOP_REVOKE+0x48
  > [ 954.6800071] 0x1065dce0: at exit1+0x784
  > [ 954.6800071] 0x1065dd90: at sigexit+0x20c
  > [ 954.7000105] 0x1065ddc0: at postsig+0x284
  > [ 954.7000105] 0x1065de70: at lwp_userret+0x204
  > [ 954.7000105] 0x1065deb0: at syscall+0x4cc
  > [ 954.7400380]             r1=0xffffe440 cr=0x22082224 xer=0 ctr=0xfdc30d30
  > [ 954.7400380] cpu1: End traceback...
  > [ 954.7700474] halting CPU 0
 
 revoke is evil :-(
 
  > Not reproducable.
  > 
  > >How-To-Repeat:
  > Only saw it once.
 
 At least twice now; see 56290.
 (noting this is the real purpose of this email)
 
 If you see it again, might be useful to try to check what device it's
 the vnode for. (Also maybe if the open count is something reasonable
 like 1 or 2, or garbage or deadbeef.)
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost