diff --git a/tools/test/stress2/misc/all.exclude b/tools/test/stress2/misc/all.exclude
index 2f4e04473eff..022075e63cb4 100644
--- a/tools/test/stress2/misc/all.exclude
+++ b/tools/test/stress2/misc/all.exclude
@@ -1,87 +1,94 @@
 # List of tests not to run, unless the '-a' option is used with run.sh
 # Exclude names must start in column 1
 
 backingstore.sh		g_vfs_done():md6a[WRITE(offset=...)]error = 28			20111220
 backingstore2.sh	panic: 43 vncache entries remaining				20111220
 backingstore3.sh	g_vfs_done():md6a[WRITE(offset=...)]error = 28			20111230
 dd.sh			CAM stuck in vmwait						20200116
+force13.sh		https://people.freebsd.org/~pho/stress/log/log0376.txt		20221113
+force14.sh		Waiting for fix							20230319
+force15.sh		Waiting for fix							20230319
 force4.sh		https://people.freebsd.org/~pho/stress/log/log0082.txt		20210328
 force7.sh		https://people.freebsd.org/~pho/stress/log/log0266.txt		20220207
-force13.sh		https://people.freebsd.org/~pho/stress/log/log0376.txt		20221113
+fsck10.sh		Waiting for fix							20230319
+fsck11.sh		Waiting for fix							20230319
+fsck12.sh		Waiting for fix							20230319
 fsync.sh		panic: Journal overflow						20190208
 fuse.sh			Memory corruption seen in log file kostik734.txt		20141114
 fuse2.sh		Deadlock seen							20121129
 fuse3.sh		Deadlock seen							20141120
 getrandom.sh		Known DoS issue							20201107
 getrandom2.sh		Known DoS issue							20200302
 gjournal.sh		panic: Journal overflow						20190626
 gjournal2.sh		panic: Journal overflow						20180125
 gjournal3.sh		panic: Bio not on queue						20171225
 gjournal4.sh		CAM stuck in vmwait						20180517
+gnop10.sh		Waiting for fix							20230319
+gnop13.sh		https://people.freebsd.org/~pho/stress/log/log0386.txt		20221113
 gnop7.sh		Waiting for patch commit					20190820
 gnop8.sh		Waiting for patch commit					20201214
 gnop9.sh		Waiting for patch commit					20201214
-gnop13.sh		https://people.freebsd.org/~pho/stress/log/log0386.txt		20221113
 graid1_8.sh		Known issue							20170909
 graid1_9.sh		panic: Bad effnlink						20180212
 ifconfig.sh		Bug 253824							20210322
 ifconfig2.sh		https://people.freebsd.org/~pho/stress/log/log0051.txt		20210210
 lockf5.sh		Spinning threads seen						20160718
 maxvnodes2.sh		https://people.freebsd.org/~pho/stress/log/log0083.txt		20210329
 memguard.sh		https://people.freebsd.org/~pho/stress/log/log0088.txt		20210402
 memguard2.sh		Waiting for fix commit
 memguard3.sh		Waiting for fix commit
 mlockall2.sh		Unrecoverable OOM killing seen					20190203
 mlockall7.sh		Needs further investigation					20210123
 msetdomain.sh		May change policy for random threads to domainset_fixed		20210104
 newfs4.sh		watchdog fired. newbuf						20190225
 nfs10.sh		Double fault							20151013
 nfs13.sh		mount_nfs hangs in mntref					20191007
 nfs15lockd.sh		panic: Assertion td->td_realucred == td->td_ucred failed ...	20210211
 nfs16.sh		panic: Failed to register NFS lock locally - error=11		20160608
 nullfs28.sh		Hang in "mount drain" seen					20220111
 oom2.sh			Hang in pfault							20180324
 overcommit2.sh		CAM stuck in vmwait seen					20200112
 pageout.sh		panic: handle_written_filepage: not started			20190218
 pmc8.sh			panic: [pmc,2749] (ri21, rc1) waiting too long for pmc to ...	20210621
 sctp2.sh		panic: Queues are not empty when handling SHUTDOWN-COMPLETE	20210211
 sctp3.sh		panic: Queues are not empty when handling SHUTDOWN-COMPLETE	20210211
 sendfile25.sh		WiP								20200611
 signal.sh		Timing issues. Needs fixing					20171116
 snap8.sh		https://people.freebsd.org/~pho/stress/log/log0123.txt		20211008
+suj12.sh		Waiting for fix							20230319
 suj19.sh		https://people.freebsd.org/~pho/stress/log/log0378.txt		20221113
 suj27.sh		https://people.freebsd.org/~pho/stress/log/log0387.txt		20221113
 suj36.sh		https://people.freebsd.org/~pho/stress/log/log0392.txt		20221114
 swapoff2.sh		swap_pager_force_pagein: read from swap failed			20171223
 swapoff3.sh		Excessive OOM killing						20220403
 swapoff5.sh		log0005.txt, known issue					20210111
 systrace.sh		WiP								20200227
 systrace2.sh		WiP								20200227
 syzkaller15.sh		WiP								20200712
 syzkaller16.sh		WiP								20210722
 syzkaller25.sh		WiP								20201116
 syzkaller27.sh		watchdogd fires							20220512
 syzkaller28.sh		WiP								20201120
 syzkaller50.sh		panic: Assertion done != job_total_nbytes failed at ...		20220405
 syzkaller54.sh		panic: td 0xfffffe014f7193a0 is not suspended			20220527
 syzkaller55.sh		panic: Counter goes negative					20220525
 syzkaller59.sh		Page fault							20220625
 syzkaller65.sh		Waiting for fix							20230318
 truss3.sh		WiP								20200915
 unionfs9.sh		https://people.freebsd.org/~pho/stress/log/log0404.txt		20230110
 
 # Test not to run for other reasons:
 
 fuzz.sh			A know issue
 marcus3.sh		OK, but runs for a long time
 statfs.sh		Not very interesting
 vunref.sh		No problems ever seen
 vunref2.sh		No problems ever seen
 
 # Exclude NFS loopback tests
 nfs2.sh			panic: wrong diroffset						20140219
 nfs5.sh
 nfs6.sh
 nfs11.sh		vmwait deadlock							20151004
 nullfs8.sh
 tmpfs18.sh		mntref hang seen						20191019
diff --git a/tools/test/stress2/misc/force14.sh b/tools/test/stress2/misc/force14.sh
new file mode 100755
index 000000000000..eec850c50891
--- /dev/null
+++ b/tools/test/stress2/misc/force14.sh
@@ -0,0 +1,119 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# 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.
+#
+
+# SU+J Snapshot test with a 50G file system
+
+# "panic: handle_jwork: Unknown type jnewblk" seen:
+# https://people.freebsd.org/~pho/stress/log/log0422.txt
+
+# "panic: flush_pagedep_deps: failed to flush inodedep..." seen:
+# https://people.freebsd.org/~pho/stress/log/log0423.txt
+
+# "panic: softdep_deallocate_dependencies: dangling deps" seen:
+# https://people.freebsd.org/~pho/stress/log/log0424.txt
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+. ../default.cfg
+
+set -u
+log=/tmp/force14.sh.log
+mount | grep $mntpoint | grep -q /dev/md && umount -f $mntpoint
+mdconfig -l | grep -q md$mdstart && mdconfig -d -u $mdstart
+truncate -s 50g $diskimage
+mdconfig -a -t vnode -f $diskimage -u $mdstart
+flags="-j"
+
+newfs $flags md$mdstart > /dev/null 2>&1
+
+# Exclude rename for now due to log0374.txt
+export TESTPROGS=`cd ..; find testcases/ -perm -1 -type f | \
+    egrep -Ev "/run/|/badcode/|/pty/|/shm/|/socket/|sysctl|tcp|thr|udp|rename"`
+export runRUNTIME=3m
+export RUNDIR=$mntpoint/stressX
+export CTRLDIR=$mntpoint/stressX.control
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt $((15 * 60)) ]; do
+	mount /dev/md$mdstart $mntpoint
+	rm -fr $mntpoint/lost+found
+	chmod 777 $mntpoint
+
+	su $testuser -c 'cd ..; ./testcases/run/run $TESTPROGS' > \
+	    /dev/null 2>&1 &
+
+	t=`jot -r 1 60 180`
+	st=`date +%s`
+	mkdir -p $mntpoint/.snap
+	for i in `jot 10`; do
+		rm -f $mntpoint/.snap/$i
+		mksnap_ffs $mntpoint $mntpoint/.snap/$i ||
+		    { ../tools/killall.sh; break; }
+		sleep `jot -r 1 1 5`
+		[ $((`date +%s` - st)) -ge $t ] && break
+	done &
+	sleep `jot -r 1 60 180`
+	while mdconfig -l | grep -q md$mdstart; do
+		mdconfig -d -u $mdstart -o force || sleep 1
+	done
+	sleep 1
+	../tools/killall.sh
+	wait
+	n=0
+	while mount | grep -q "on $mntpoint "; do
+		umount $mntpoint || sleep 1
+		[ $((n += 1)) -gt 300 ] && { echo FAIL; exit 1; }
+	done
+	mdconfig -a -t vnode -f $diskimage -u $mdstart
+	c=0
+	# Process the journal
+	fsck_ffs -fy /dev/md$mdstart > $log 2>&1; s=$?
+	grep 'INTERNAL ERROR: GOT TO reply' $log
+	for i in `jot 4`; do
+		[ $i -ne 1 ]  &&
+		    echo "fsck_ffs -fy /dev/md$mdstart"
+		fsck_ffs -fy /dev/md$mdstart > $log 2>&1; s=$?
+		grep 'INTERNAL ERROR: GOT TO reply' $log
+		grep -q CLEAN $log && c=$((c+=1))
+		grep -Eq "WAS MODIFIED" $log || break
+	done
+	[ $c -gt 1 ] &&
+	    { echo "Note: FS marked clean+modified $c times out of $i fsck runs"; s=101; }
+	[ $s -ne 0 ] && break
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log || { s=102; break; }
+done
+if [ $s -eq 0 ]; then
+	mount /dev/md$mdstart $mntpoint
+	cp -R /usr/include $mntpoint
+	dd if=/dev/zero of=$mntpoint/big bs=1m count=10 status=none
+	find $mntpoint/* -delete
+
+	umount $mntpoint
+	mdconfig -d -u $mdstart
+	rm -f $diskimage $log
+fi
+exit $s
diff --git a/tools/test/stress2/misc/force15.sh b/tools/test/stress2/misc/force15.sh
new file mode 100755
index 000000000000..955025cd98c6
--- /dev/null
+++ b/tools/test/stress2/misc/force15.sh
@@ -0,0 +1,113 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+# FFS+SU with snapshots and forced unmounts
+
+# "panic: flush_pagedep_deps: failed to flush inodedep ..." seen
+# https://people.freebsd.org/~pho/stress/log/log0427.txt
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+
+prog=$(basename "$0" .sh)
+diskimage=/tmp/diskimage
+log=/tmp/$prog.log
+mdstart=10
+mntpoint=/mnt
+newfs_flags="-U"
+
+set -u
+mount | grep $mntpoint | grep -q /dev/md && umount -f $mntpoint
+mdconfig -l | grep -q md$mdstart && mdconfig -d -u $mdstart
+dd if=/dev/zero of=$diskimage bs=1m count=1k status=none
+mdconfig -a -t vnode -f $diskimage -u $mdstart
+flags="-U"
+
+newfs $flags md$mdstart > /dev/null 2>&1
+
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt $((5 * 60)) ]; do
+	mount /dev/md$mdstart $mntpoint
+	rm -fr $mntpoint/lost+found
+
+	jot 10 | xargs -I% mkdir -p $mntpoint/%
+	n=5000
+	for j in `jot 10`; do
+		(
+			jot $n | xargs -P0 -I% touch $mntpoint/$j/%
+			jot $n | xargs -P0 -I% rm    $mntpoint/$j/%
+		) > /dev/null 2>&1 &
+	done 
+
+	sleep `jot -r 1 5 20`
+	t=`jot -r 1 60 180`
+	st=`date +%s`
+	mkdir -p $mntpoint/.snap
+	for i in `jot 10`; do
+		rm -f $mntpoint/.snap/$i
+		mksnap_ffs $mntpoint $mntpoint/.snap/$i > /dev/null 2>&1 || break
+		sleep `jot -r 1 1 5`
+		[ $((`date +%s` - st)) -ge $t ] && break
+	done &
+	sleep `jot -r 1 2 5`
+	while mdconfig -l | grep -q md$mdstart; do
+		mdconfig -d -u $mdstart -o force || sleep 1
+	done
+	sleep 1
+	wait
+	n=0
+	while mount | grep -q "on $mntpoint "; do
+		umount $mntpoint || sleep 1
+		[ $((n += 1)) -gt 300 ] && { echo FAIL; exit 1; }
+	done
+	mdconfig -a -t vnode -f $diskimage -u $mdstart
+	c=0
+	for i in `jot 5`; do
+		[ $i -ne 1 ] &&
+		    echo "$i: fsck_ffs -fy /dev/md$mdstart"
+		fsck_ffs -fy /dev/md$mdstart > $log 2>&1; s=$?
+		grep 'INTERNAL ERROR: GOT TO reply' $log
+		grep -q CLEAN $log && grep -q MODIFIED && c=$((c+=1))
+		grep -Eq "WAS MODIFIED" $log || break
+	done
+	[ $c -gt 1 ] &&
+	    { echo "Note: FS marked clean+modified $c times out of $i fsck runs"; s=101; }
+	[ $s -ne 0 ] && break
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log || { s=102; break; }
+done
+if [ $s -eq 0 ]; then
+	mount /dev/md$mdstart $mntpoint
+	cp -R /usr/include $mntpoint
+	dd if=/dev/zero of=$mntpoint/big bs=1m count=10 status=none
+	find $mntpoint/* -delete
+
+	umount $mntpoint
+	mdconfig -d -u $mdstart
+	rm -f $diskimage $log
+fi
+exit $s
diff --git a/tools/test/stress2/misc/fsck10.sh b/tools/test/stress2/misc/fsck10.sh
new file mode 100755
index 000000000000..30479e0dfebb
--- /dev/null
+++ b/tools/test/stress2/misc/fsck10.sh
@@ -0,0 +1,171 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+# Variation of fsck9.sh with smaller disk size and newfs options '', 'U' and 'O1'
+# fsck_ffs core dump seen
+
+. ../default.cfg
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+
+cc -o /tmp/flip -Wall -Wextra -O2 ../tools/flip.c || exit 1
+
+set -e
+prog=$(basename "$0" .sh)
+u1=$mdstart
+u2=$((mdstart + 1))
+mp1=${mntpoint}$u1
+mp2=${mntpoint}$u2
+mkdir -p $mp1 $mp2
+log=$mp1/$prog.sh.log
+diskimage=$mp1/$prog.sh.diskimage
+backup=/tmp/$prog.sh.diskimage.`date +%Y%m%dT%H%M%S`.gz
+cleans=0
+reruns=0
+
+# Pick a random newfs flag
+newfs_flags=$(echo "" "-U" "-O1" | awk -v N=`jot -r 1 1 3` '{print $N}')
+[ $# -eq 1 ] && newfs_flags="$1" # or use script argument
+max=$((512 * 1024))
+
+mount | grep "on $mp1 " | grep -q /dev/md && umount -f $mp1
+[ -c /dev/md$u1 ] && mdconfig -d -u $u1
+mdconfig -a -t swap -s 1g -u $u1
+newfs $newfs_flags -n /dev/md$u1 > /dev/null
+mount /dev/md$u1 $mp1
+
+[ -c /dev/md$u2 ] && mdconfig -d -u $u2
+dd if=/dev/zero of=$diskimage bs=$max count=1 status=none
+mdconfig -a -t vnode -f $diskimage -u $u2
+backups=`newfs -N $newfs_flags md$u2 | grep -A1 "super-block backups" | \
+    tail -1 | sed 's/,//g'`
+echo "newfs $newfs_flags -n md$u2"
+newfs $newfs_flags -n md$u2 > /dev/null
+set +e
+
+chk() {
+	local i
+
+	clean=0
+	rerun=0
+	fsck_ffs -fy $1 > $log 2>&1
+	r=$?
+	if grep -qiE "super-?block.*failed" $log; then
+		for b in $backups; do
+			echo "fsck_ffs -b $b -fy $1"
+			fsck_ffs -b $b -fy $1 > $log 2>&1
+			r=$?
+			grep -qiE "super-?block.*failed" $log ||
+			   break
+			echo "Checking next SB"
+		done
+		usedasb=1
+	else
+		usedasb=0
+	fi
+	LANG=C egrep -q "[A-Z][A-Z]" $log && clean=0
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log && clean=1
+	grep -q RERUN $log && rerun=1
+	[ $r -ne 0 -a $clean -eq 1 ] && echo "Exit code $r w/ clean == 1"
+}
+
+cd $mp1
+clean=0
+errors=0
+s=0
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt 300 ]; do
+	mount /dev/md$u2 $mp2 || break
+	if ! ls -lR $mp2 > /dev/null; then
+		s=102
+		echo "ls failed"; grep "core dumped" /var/log/messages | tail -1
+		break
+	fi
+	rm -f $mp2/????????
+	touch $mp2/`jot -rc 8 a z | tr -d '\n'`
+	mkdir -p $mp2/dir/dir/dir/dir
+	echo "abc" > $mp2/dir/dir/dir/dir/f
+	while mount | grep -q "on $mp2 "; do umount $mp2; done
+	echo * | grep -q core && break
+	mdconfig -d -u $u2
+
+	# Introduce 5 random single bit errors to the file system image
+	/tmp/flip -n 5 $diskimage
+
+	sync; sleep .1
+	if [ `stat -f%z $diskimage` -gt $max ]; then
+		ls -lh $diskimage
+		truncate -s $max $diskimage
+	else
+		gzip < $diskimage > $backup
+	fi
+	fsync $backup
+	sync; sleep .1
+
+	for i in `jot 5`; do
+		[ $i -gt 2 ] && echo "fsck run #$i"
+		chk $diskimage
+		[ $rerun -eq 1 ] && { reruns=$((reruns + 1)); continue; }
+		[ $clean -eq 1 ] && { cleans=$((cleans + 1)); break; }
+		if [ -f fsck_ffs.core ]; then
+			tstamp=`date +%Y%m%dT%H%M%S`
+			gzip < $backup > /tmp/fsck_ffs.core.diskimage.$tstamp
+			gzip < fsck_ffs.core > /tmp/fsck_ffs.core.$tstamp
+			break 2
+		fi
+	done
+	if [ $clean -eq 1 ]; then
+		fsck_ffs -fy $diskimage > $log 2>&1
+		if grep -q MODIFIED $log; then
+			echo "*** fsck of \"clean\" FS found more issues:"
+			cat $log
+			errors=$((errors + 1))
+			s=1
+			break
+		fi
+	fi
+	[ $clean -ne 1 ] && break
+	mdconfig -a -t vnode -f $diskimage -u $u2
+done
+for i in `jot 5`; do
+	mount | grep -q "on $mp2 " || break
+	umount $mp2 && break
+	sleep 2
+done
+mdconfig -l | grep -q $u2 && mdconfig -d -u $u2
+
+[ $s -eq 0 ] && rm -f $backup || echo "Preserved $backup due to status code $s"
+cd /tmp
+for i in `jot 5`; do
+	umount $mp1 && break
+	sleep 2
+done
+mdconfig -d -u $u1
+rm -f /tmp/flip
+exit $s
diff --git a/tools/test/stress2/misc/fsck11.sh b/tools/test/stress2/misc/fsck11.sh
new file mode 100755
index 000000000000..cb5d1d256be6
--- /dev/null
+++ b/tools/test/stress2/misc/fsck11.sh
@@ -0,0 +1,170 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# 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.
+#
+
+# Demonstrate how the "CLEAN" message and the exit code can be misleading
+
+# "panic: softdep_update_inodeblock inconsistent ip ..." seen:
+# https://people.freebsd.org/~pho/stress/log/log0421.txt
+# https://people.freebsd.org/~pho/fsck11.sh.diskimage.20230228T064402.gz
+
+. ../default.cfg
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+
+cc -o /tmp/flip -Wall -Wextra -O2 ../tools/flip.c || exit 1
+
+set -e
+prog=$(basename "$0" .sh)
+u1=$mdstart
+u2=$((mdstart + 1))
+mp1=${mntpoint}$u1
+mp2=${mntpoint}$u2
+mkdir -p $mp1 $mp2
+log=$mp1/$prog.sh.log
+diskimage=$mp1/$prog.sh.diskimage
+backup=/tmp/$prog.sh.diskimage.`date +%Y%m%dT%H%M%S`.gz
+cleans=0
+reruns=0
+
+# Pick a random newfs flag
+newfs_flags=$(echo "" "-U" "-O1" | awk -v N=`jot -r 1 1 3` '{print $N}')
+[ $# -eq 1 ] && newfs_flags="$1" # or use script argument
+max=$((2 * 1024 * 1024))
+[ "$newfs_flags" == "-j" ] && max=$((20 * 1024 * 1024)) # Make room for the journal file
+
+mount | grep "on $mp1 " | grep -q /dev/md && umount -f $mp1
+[ -c /dev/md$u1 ] && mdconfig -d -u $u1
+mdconfig -a -t swap -s 1g -u $u1
+newfs $newfs_flags -n /dev/md$u1 > /dev/null
+mount /dev/md$u1 $mp1
+
+[ -c /dev/md$u2 ] && mdconfig -d -u $u2
+dd if=/dev/zero of=$diskimage bs=$max count=1 status=none
+mdconfig -a -t vnode -f $diskimage -u $u2
+backups=`newfs -N $newfs_flags md$u2 | grep -A1 "super-block backups" | \
+    tail -1 | sed 's/,//g'`
+echo "newfs $newfs_flags -n md$u2"
+newfs $newfs_flags -n md$u2 > /dev/null
+set +e
+
+chk() {
+	local i
+
+	clean=0
+	rerun=0
+	fsck_ffs -fy $1 > $log 2>&1
+	r=$?
+	if grep -qiE "super-?block.*failed" $log; then
+		for b in $backups; do
+			echo "fsck_ffs -b $b -fy $1"
+			fsck_ffs -b $b -fy $1 > $log 2>&1
+			r=$?
+			grep -qiE "super-?block.*failed" $log ||
+			   break
+			echo "Checking next SB"
+		done
+		usedasb=1
+	else
+		usedasb=0
+	fi
+	LANG=C egrep -q "[A-Z][A-Z]" $log && clean=0
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log && clean=1
+	grep -q RERUN $log && rerun=1
+	[ $r -ne 0 -a $clean -eq 1 ] && echo "Exit code $r w/ clean == 1"
+}
+
+cd $mp1
+clean=0
+errors=0
+s=0
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt 300 ]; do
+	mount /dev/md$u2 $mp2 || break
+	if ! ls -lR $mp2 > /dev/null; then
+		s=102
+		echo "ls failed"; grep "core dumped" /var/log/messages | tail -1
+		break
+	fi
+
+	find $mp2 -type f | xargs cat > /dev/null
+	for j in `jot 9`; do
+		rm -rf $mp2/$j
+		mkdir $mp2/$j
+		jot 10 | xargs -P0 -I% cp /etc/group $mp2/$j/%
+	done 2>/dev/null
+
+	while mount | grep -q "on $mp2 "; do umount $mp2; done
+	echo * | grep -q core && break
+	mdconfig -d -u $u2
+
+	# Introduce 5 random single bit errors to the file system image
+	/tmp/flip -n 5 $diskimage
+
+	if [ `stat -f%z $diskimage` -gt $max ]; then
+		ls -lh $diskimage
+		truncate -s $max $diskimage
+	else
+		gzip < $diskimage > $backup
+	fi
+	fsync $backup
+	sync; sleep 1
+
+	[ $newfs_flags == "-j" ] &&
+		fsck -fy $diskimage > $log 2>&1	# process the journal file
+	for i in `jot 5`; do
+		[ $i -gt 2 ] && echo "fsck run #$i"
+		chk $diskimage
+		[ $rerun -eq 1 ] && { reruns=$((reruns + 1)); continue; }
+		[ $clean -eq 1 ] && { cleans=$((cleans + 1)); break; }
+		if [ -f fsck_ffs.core ]; then
+			tstamp=`date +%Y%m%dT%H%M%S`
+			gzip < $backup > /tmp/fsck_ffs.core.diskimage.$tstamp
+			gzip < fsck_ffs.core > /tmp/fsck_ffs.core.$tstamp
+			break 2
+		fi
+	done
+	[ $clean -ne 1 ] && { s=99; break; }	# broken image?
+	mdconfig -a -t vnode -f $diskimage -u $u2
+done
+for i in `jot 5`; do
+	mount | grep -q "on $mp2 " || break
+	umount $mp2 && break
+	sleep 2
+done
+mdconfig -l | grep -q $u2 && mdconfig -d -u $u2
+
+[ $s -eq 0 ] && rm -f $backup || echo "Preserved $backup due to status code $s"
+cd /tmp
+for i in `jot 5`; do
+	umount $mp1 && break
+	sleep 2
+done
+mdconfig -d -u $u1
+rm -f /tmp/flip
+exit $s
diff --git a/tools/test/stress2/misc/fsck12.sh b/tools/test/stress2/misc/fsck12.sh
new file mode 100755
index 000000000000..d2787e962927
--- /dev/null
+++ b/tools/test/stress2/misc/fsck12.sh
@@ -0,0 +1,177 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+# "panic: ffs_copyonwrite: bad copy block" seen:
+# Hunt for fsck_ffs's INTERNAL ERROR message
+
+# https://people.freebsd.org/~pho/stress/log/log0426.txt
+
+. ../default.cfg
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+
+cc -o /tmp/flip -Wall -Wextra -O2 ../tools/flip.c || exit 1
+
+set -e
+prog=$(basename "$0" .sh)
+u1=$mdstart
+u2=$((mdstart + 1))
+mp1=${mntpoint}$u1
+mp2=${mntpoint}$u2
+mkdir -p $mp1 $mp2
+log=$mp1/$prog.sh.log
+diskimage=$mp1/$prog.sh.diskimage
+backup=/tmp/$prog.sh.diskimage.`date +%Y%m%dT%H%M%S`.gz
+cleans=0
+reruns=0
+
+mount | grep "on $mp1 " | grep -q /dev/md && umount -f $mp1
+[ -c /dev/md$u1 ] && mdconfig -d -u $u1
+mdconfig -a -t swap -s 1g -u $u1
+newfs $newfs_flags -n /dev/md$u1 > /dev/null
+mount /dev/md$u1 $mp1
+
+newfs_flags='-j'
+[ $# -eq 1 ] && newfs_flags="$1" # or use script argument
+max=$((2 * 1024 * 1024))
+[ "$newfs_flags" == "-j" ] && max=$((20 * 1024 * 1024)) # Make room for the journal file
+
+[ -c /dev/md$u2 ] && mdconfig -d -u $u2
+dd if=/dev/zero of=$diskimage bs=$max count=1 status=none
+mdconfig -a -t vnode -f $diskimage -u $u2
+backups=`newfs -N $newfs_flags md$u2 | grep -A1 "super-block backups" | \
+    tail -1 | sed 's/,//g'`
+echo "newfs $newfs_flags md$u2"
+newfs $newfs_flags md$u2 > /dev/null
+set +e
+
+chk() {
+	local i
+
+	clean=0
+	rerun=0
+	fsck_ffs -fy $1 > $log 2>&1
+	r=$?
+	grep "GOT TO reply" $log && exit 1
+	if grep -qiE "super-?block.*failed" $log; then
+		for b in $backups; do
+			echo "fsck_ffs -b $b -fy $1"
+			fsck_ffs -b $b -fy $1 > $log 2>&1
+			r=$?
+			grep "GOT TO reply" $log && exit 1
+			grep -qiE "super-?block.*failed" $log ||
+			   break
+			echo "Checking next SB"
+		done
+		usedasb=1
+	else
+		usedasb=0
+	fi
+	LANG=C egrep -q "[A-Z][A-Z]" $log && clean=0
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log && clean=1
+	grep -q RERUN $log && rerun=1
+	[ $r -ne 0 -a $clean -eq 1 ] && echo "Exit code $r w/ clean == 1"
+}
+
+cd $mp1
+clean=0
+errors=0
+s=0
+sno=0
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt 300 ]; do
+	mount /dev/md$u2 $mp2 || break
+	if ! ls -lR $mp2 > /dev/null; then
+		s=102
+		echo "ls failed"; grep "core dumped" /var/log/messages | tail -1
+		break
+	fi
+	mkdir -p $mp2/d/d/d/d/d
+	cp /etc/group $mp2/d/d/d/d/d/f
+	for i  in `jot 20`; do
+		cp -r $mp2/d $i
+	done
+
+	rm -f $mp2/.snap/$sno
+	mksnap_ffs $mp2 $mp2/.snap/$sno &
+	sno=$(((sno + 1) % 10))
+		
+	sleep 1
+	rm -rf $mp/?
+	wait
+	while mount | grep -q "on $mp2 "; do umount $mp2; done
+	echo * | grep -q core && break
+	mdconfig -d -u $u2
+
+	# Introduce 5 random single bit errors to the file system image
+	/tmp/flip -n 5 $diskimage
+
+	if [ `stat -f%z $diskimage` -gt $max ]; then
+		ls -lh $diskimage
+		truncate -s $max $diskimage
+	else
+		gzip < $diskimage > $backup
+	fi
+	fsync $backup
+	sync; sleep 1
+
+	[ $newfs_flags == "-j" ] &&
+		fsck -fy $diskimage > $log 2>&1	# process the journal file
+	for i in `jot 5`; do
+		[ $i -gt 2 ] && echo "fsck run #$i"
+		chk $diskimage
+		[ $rerun -eq 1 ] && { reruns=$((reruns + 1)); continue; }
+		grep -q "MODIFIED" $log && continue # For now, do not trust CLEAN
+		[ $clean -eq 1 ] && { cleans=$((cleans + 1)); break; }
+		if [ -f fsck_ffs.core ]; then
+			tstamp=`date +%Y%m%dT%H%M%S`
+			gzip < $backup > /tmp/fsck_ffs.core.diskimage.$tstamp.gz
+			gzip < fsck_ffs.core > /tmp/fsck_ffs.core.$tstamp.gz
+			break 2
+		fi
+	done
+	[ $clean -ne 1 ] && { s=99; break; }	# broken image?
+	mdconfig -a -t vnode -f $diskimage -u $u2
+done
+for i in `jot 5`; do
+	mount | grep -q "on $mp2 " || break
+	umount $mp2 && break
+	sleep 2
+done
+mdconfig -l | grep -q $u2 && mdconfig -d -u $u2
+
+[ $s -eq 0 ] && rm -f $backup || echo "Preserved $backup due to status code $s"
+cd /tmp
+for i in `jot 5`; do
+	umount $mp1 && break
+	sleep 2
+done
+mdconfig -d -u $u1
+rm -f /tmp/flip
+exit $s
diff --git a/tools/test/stress2/misc/gnop13.sh b/tools/test/stress2/misc/gnop13.sh
new file mode 100755
index 000000000000..45668b9d8e82
--- /dev/null
+++ b/tools/test/stress2/misc/gnop13.sh
@@ -0,0 +1,138 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Peter Holm <pho@FreeBSD.org>
+#
+# 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.
+#
+
+# Snapshot test
+# Variation of force13.sh, but uses "gnop -f destroy"
+
+# Seen:
+# UFS: forcibly unmounting /dev/md10.nop from /mnt
+# panic: flush_pagedep_deps: failed to flush inodedep
+
+[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
+. ../default.cfg
+
+set -u
+log=/tmp/gnop13.sh.log
+mount | grep $mntpoint | grep -q /dev/md && umount -f $mntpoint
+mdconfig -l | grep -q md$mdstart && mdconfig -d -u $mdstart
+truncate -s 10g $diskimage
+mdconfig -a -t vnode -f $diskimage -u $mdstart
+flags=$newfs_flags
+[ `jot -r 1 0 1` -eq 1 ] && flags="-j"
+
+echo "newfs $flags md$mdstart"
+newfs $flags md$mdstart > /dev/null 2>&1
+
+# Exclude rename for now due to log0374.txt
+export TESTPROGS=`cd ..; find testcases/ -perm -1 -type f | \
+    egrep -Ev "/run/|/badcode/|/pty/|/shm/|/socket/|sysctl|tcp|thr|udp|rename"`
+export runRUNTIME=3m
+export RUNDIR=$mntpoint/stressX
+export CTRLDIR=$mntpoint/stressX.control
+start=`date +%s`
+while [ $((`date +%s` - start)) -lt $((15 * 60)) ]; do
+	gnop create /dev/md$mdstart || exit 1
+	mount /dev/md$mdstart.nop $mntpoint || exit 1
+	rm -fr $mntpoint/lost+found
+	chmod 777 $mntpoint
+
+	su $testuser -c 'cd ..; ./testcases/run/run $TESTPROGS' > \
+	    /dev/null 2>&1 &
+
+	t=`jot -r 1 60 120`
+	st=`date +%s`
+	for i in `jot 10`; do
+		[ -d $mntpoint/.snap ] || break
+		rm -f $mntpoint/.snap/$i
+		echo "mksnap_ffs $mntpoint $mntpoint/.snap/$i"
+		mksnap_ffs $mntpoint $mntpoint/.snap/$i
+		sleep `jot -r 1 1 5`
+		[ $((`date +%s` - st)) -ge $t ] && break
+	done &
+	sleep `jot -r 1 60 120`
+	while [ -c /dev/md$mdstart.nop ]; do
+		echo "gnop destroy -f /dev/md$mdstart.nop"
+		gnop destroy -f /dev/md$mdstart.nop || sleep 1
+	done
+	n=0
+	st=`date +%s`
+	while mount | grep -q "on $mntpoint "; do
+		[ $n -eq 0 ] && /bin/echo -n "Waiting for $mntpoint to force umount ..."
+		n=$((n + 1))
+		sleep 2
+		if [ $((`date +%s` - st)) -ge 180 ]; then
+			echo "Giving up on waiting for umount of $mntpoint"
+			umount $mntpoint || umount -f $mntpoint
+			break
+		fi
+	done
+	[ $n -ne 0 ] && echo
+
+	../tools/killall.sh
+	wait
+	mount | grep -q "on $mntpoint " && umount -f $mntpoint
+	c=0
+	# Run fsck minimum two times
+	for i in `jot 5`; do
+		fsck_ffs -fy /dev/md$mdstart > $log 2>&1; s=$?
+		grep -q CLEAN $log && grep -q "MODIFIED" $log && c=$((c+=1))
+		grep -Eq "FILE SYSTEM WAS MODIFIED" $log || break
+	done
+	[ $c -gt 1 ] &&
+	    { echo "Note: FS marked clean+modified $c times out of $i fsck runs"; s=101; }
+	[ $s -ne 0 ] && break
+	grep -Eq "IS CLEAN|MARKED CLEAN" $log || { s=102; break; }
+done
+[ $s -eq 101 ] && s=0 # Ignore CLEANish problem for now
+if [ $s -eq 0 ]; then
+	mount /dev/md$mdstart.nop $mntpoint
+	cp -R /usr/include $mntpoint
+	dd if=/dev/zero of=$mntpoint/big bs=1m count=10 status=none
+	find $mntpoint/* -delete
+
+	# Check the RO snapshots
+	for f in $mntpoint/.snap/*; do
+		c=0
+		for i in `jot 5`; do
+			echo "fsck_ffs -fy $f"
+			fsck_ffs -fy $f > $log 2>&1; s=$?
+			grep -q CLEAN $log && grep -q "MODIFIED" $log && c=$((c+=1))
+			grep -Eq "FILE SYSTEM WAS MODIFIED" $log || break
+		done
+		[ $c -gt 1 ] &&
+		    { echo "Note: snapshot $i marked clean+modified $c times out of $i fsck runs"; s=201; }
+		[ $s -ne 0 ] && break
+		grep -Eq "IS CLEAN|MARKED CLEAN" $log ||
+		    { s=202; tail -10 $log; break; }
+	done
+	umount $mntpoint
+	mdconfig -d -u $mdstart
+	rm -f $diskimage $log
+fi
+exit $s