Index: user/pho/stress2/misc/msdos6.sh
===================================================================
--- user/pho/stress2/misc/msdos6.sh	(revision 363942)
+++ user/pho/stress2/misc/msdos6.sh	(revision 363943)
@@ -1,92 +1,95 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2016 Dell EMC Isilon
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the distribution.
 #
 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 # ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 # SUCH DAMAGE.
 #
 # $FreeBSD$
 #
 
 # Parallel mount and umount of file systems
 
+# "panic: userret: Returning with 1 locks held" seen:
+# https://people.freebsd.org/~pho/stress/log/mark165.txt
+
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 . ../default.cfg
 
 mounts=15		# Number of parallel scripts
 cont=/tmp/msdos6.continue
 mdstart=$mdstart	# Use md unit numbers from this point
 
 if [ $# -eq 0 ]; then
 	touch $cont
 	mycc -o /tmp/fstool -Wall -Wextra -O2 ../tools/fstool.c || exit 1
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		[ ! -d ${mntpoint}$m ] && mkdir ${mntpoint}$m
 		mount | grep "$mntpoint" | grep -q md$m && umount ${mntpoint}$m
 		mdconfig -l | grep -q md$m &&  mdconfig -d -u $m
 
 		mdconfig -a -t swap -s 1g -u $m
 		bsdlabel -w md$m auto
 		newfs_msdos -F 32 -b 8192 /dev/md${m}$part > /dev/null 2>&1
 		mount -t msdosfs /dev/md${m}$part ${mntpoint}$m
 		(mkdir ${mntpoint}$m/test$i; cd ${mntpoint}$m/test$i; /tmp/fstool -l -f 100 -n 100 -s ${i}k)
 		umount ${mntpoint}$m > /dev/null 2>&1
 	done
 
 	# start the parallel tests
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		./$0 $m &
 		./$0 find &
 	done
 
 	wait
 
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		mdconfig -d -u $m
 	done
 	rm -f /tmp/fstool
 
 else
 	if [ $1 = find ]; then
 		while [ -r $cont ]; do
 			find ${mntpoint}* -type f > /dev/null 2>&1
 		done
 	else
 
 		# The test: Parallel mount and unmounts
 		start=`date '+%s'`
 		while [ $((`date '+%s'` - start)) -lt 300 ]; do
 			m=$1
 			mount -t msdosfs /dev/md${m}$part ${mntpoint}$m
 			while mount | grep -qw $mntpoint$m; do
 				opt=$([ $((`date '+%s'` % 2)) -eq 0 ] && echo "-f")
 				umount $opt ${mntpoint}$m > /dev/null 2>&1
 			done
 		done
 		rm -f $cont
 	fi
 fi