diff --git a/tests/sys/geom/class/concat/1_test.sh b/tests/sys/geom/class/concat/1_test.sh
index a35b015e9c24..126768370140 100644
--- a/tests/sys/geom/class/concat/1_test.sh
+++ b/tests/sys/geom/class/concat/1_test.sh
@@ -1,22 +1,22 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo '1..1'
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 gconcat create $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 # Size of created device should be 1MB + 2MB + 3MB.
 
 size=`diskinfo /dev/concat/${name} | awk '{print $3}'`
 
 if [ $size -eq 6291456 ]; then
 	echo "ok - Size is 6291456"
 else
 	echo "not ok - Size is 6291456"
 fi
diff --git a/tests/sys/geom/class/concat/2_test.sh b/tests/sys/geom/class/concat/2_test.sh
index 7b41932f054a..63e545f12297 100644
--- a/tests/sys/geom/class/concat/2_test.sh
+++ b/tests/sys/geom/class/concat/2_test.sh
@@ -1,29 +1,29 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo '1..1'
 
 tsize=6
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 dd if=/dev/random of=${src} bs=1m count=$tsize >/dev/null 2>&1
 
 gconcat create $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 dd if=${src} of=/dev/concat/${name} bs=1m count=$tsize >/dev/null 2>&1
 dd if=/dev/concat/${name} of=${dst} bs=1m count=$tsize >/dev/null 2>&1
 
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok - md5 checksum comparison"
 else
 	echo "ok - md5 checksum comparison"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/concat/append1.sh b/tests/sys/geom/class/concat/append1.sh
index 08d6250fd190..b6ac3772022b 100644
--- a/tests/sys/geom/class/concat/append1.sh
+++ b/tests/sys/geom/class/concat/append1.sh
@@ -1,46 +1,46 @@
 #!/bin/sh
 
 # A basic regression test for gconcat append using "gconcat create",
 # i.e., manual mode.
 
 gconcat_check_size()
 {
     local actual expected name
 
     name=$1
     expected=$2
 
     actual=$(diskinfo /dev/concat/${name} | awk '{print $3}')
     if [ $actual -eq $expected ]; then
         echo "ok - Size is ${actual}"
     else
         echo "not ok - Size is ${actual}"
     fi
 }
 
 . `dirname $0`/conf.sh
 
 echo '1..3'
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 1M) || exit 1
-us2=$(attach_md -t malloc -s 1M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 1M || exit 1
+attach_md us2 -t malloc -s 1M || exit 1
 
 gconcat create $name /dev/$us0 /dev/$us1 || exit 1
 devwait
 
 # We should have a 2MB device.  Add another disk and verify that the
 # reported size of the concat device grows accordingly.
 gconcat_check_size "${name}" $((2 * 1024 * 1024))
 gconcat append $name /dev/$us2 || exit 1
 gconcat_check_size "${name}" $((3 * 1024 * 1024))
 
 # Write some data and make sure that we can read it back.
 tmpfile=$(mktemp) || exit 1
 dd if=/dev/random of=$tmpfile bs=1M count=3 || exit 1
 dd if=$tmpfile of=/dev/concat/${name} || exit 1
 if cmp -s $tmpfile /dev/concat/${name}; then
     echo "ok - Data matches what was written"
 else
     echo "not ok - Data matches what was written"
 fi
diff --git a/tests/sys/geom/class/concat/append2.sh b/tests/sys/geom/class/concat/append2.sh
index 84a1f12350ba..d008e976cf57 100644
--- a/tests/sys/geom/class/concat/append2.sh
+++ b/tests/sys/geom/class/concat/append2.sh
@@ -1,77 +1,77 @@
 #!/bin/sh
 
 # A basic regression test for gconcat append using "gconcat label",
 # i.e., automatic mode.
 
 gconcat_check_size()
 {
     local actual expected name
 
     name=$1
     expected=$2
 
     actual=$(diskinfo /dev/concat/${name} | awk '{print $3}')
     if [ $actual -eq $expected ]; then
         echo "ok - Size is ${actual}"
     else
         echo "not ok - Size is ${actual}"
     fi
 }
 
 . `dirname $0`/conf.sh
 
 echo '1..4'
 
 ss=512
 
 f1=$(mktemp) || exit 1
 truncate -s $((1024 * 1024 + $ss)) $f1
 f2=$(mktemp) || exit 1
 truncate -s $((1024 * 1024 + $ss)) $f2
 f3=$(mktemp) || exit 1
 truncate -s $((1024 * 1024 + $ss)) $f3
 
-us0=$(attach_md -f $f1 -S $ss) || exit 1
-us1=$(attach_md -f $f2 -S $ss) || exit 1
-us2=$(attach_md -f $f3 -S $ss) || exit 1
+attach_md us0 -f $f1 -S $ss || exit 1
+attach_md us1 -f $f2 -S $ss || exit 1
+attach_md us2 -f $f3 -S $ss || exit 1
 
 gconcat label $name /dev/$us0 /dev/$us1 || exit 1
 devwait
 
 # We should have a 2MB device.  Add another disk and verify that the
 # reported size of the concat device grows accordingly.  A sector from
 # each disk is reserved for the metadata sector.
 gconcat_check_size "${name}" $((2 * 1024 * 1024))
 gconcat append $name /dev/$us2 || exit 1
 gconcat_check_size "${name}" $((3 * 1024 * 1024))
 
 copy=$(mktemp) || exit 1
 dd if=/dev/random of=$copy bs=1M count=3 || exit 1
 dd if=$copy of=/dev/concat/${name} || exit 1
 
 # Stop the concat device and destroy the backing providers.
 gconcat stop ${name} || exit 1
 detach_md $us0
 detach_md $us1
 detach_md $us2
 
 # Re-create the providers and verify that the concat device comes
 # back and that the data is still there.
-us0=$(attach_md -f $f1 -S $ss) || exit 1
-us1=$(attach_md -f $f2 -S $ss) || exit 1
-us2=$(attach_md -f $f3 -S $ss) || exit 1
+attach_md us0 -f $f1 -S $ss || exit 1
+attach_md us1 -f $f2 -S $ss || exit 1
+attach_md us2 -f $f3 -S $ss || exit 1
 
 devwait
 
 # Make sure that the
 if [ -c /dev/concat/${name} ]; then
     echo "ok - concat device was instantiated"
 else
     echo "not ok - concat device was instantiated"
 fi
 
 if cmp -s $copy /dev/concat/${name}; then
     echo "ok - Data was persisted across gconcat stop"
 else
     echo "not ok - Data was persisted across gconcat stop"
 fi
diff --git a/tests/sys/geom/class/eli/attach_test.sh b/tests/sys/geom/class/eli/attach_test.sh
index bdb39a806fca..eb59234f014b 100644
--- a/tests/sys/geom/class/eli/attach_test.sh
+++ b/tests/sys/geom/class/eli/attach_test.sh
@@ -1,129 +1,129 @@
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case attach_d cleanup
 attach_d_head()
 {
 	atf_set "descr" "geli attach -d will cause the provider to detach on last close"
 	atf_set "require.user" "root"
 }
 attach_d_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check geli attach -d -p -k keyfile ${md}
 
 	# Be sure it doesn't detach on read.
 	atf_check dd if=/dev/${md}.eli of=/dev/null status=none
 	sleep 1
 	if [ ! -c /dev/${md}.eli ]; then
 		atf_fail "Detached on last close of a reader"
 	fi
 
 	# It should detach on last close of a writer
 	true > /dev/${md}.eli
 	sleep 1
 	if [ -c /dev/${md}.eli ]; then
 		atf_fail "Did not detach on last close of a writer"
 	fi
 
 }
 attach_d_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case attach_r cleanup
 attach_r_head()
 {
 	atf_set "descr" "geli attach -r will create a readonly provider"
 	atf_set "require.user" "root"
 }
 attach_r_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check geli attach -r -p -k keyfile ${md}
 
 	atf_check -o match:"^Flags: .*READ-ONLY" geli list ${md}.eli
 
 	# Verify that writes are verbotten
 	atf_check -s not-exit:0 -e match:"Read-only" \
 		dd if=/dev/zero of=/dev/${md}.eli count=1
 }
 attach_r_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case attach_multiple cleanup
 attach_multiple_head()
 {
 	atf_set "descr" "geli attach can attach multiple providers"
 	atf_set "require.user" "root"
 }
 attach_multiple_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md0=$(attach_md -t malloc -s `expr $sectors + 1`)
-	md1=$(attach_md -t malloc -s `expr $sectors + 1`)
-	md2=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md0 -t malloc -s `expr $sectors + 1`
+	attach_md md1 -t malloc -s `expr $sectors + 1`
+	attach_md md2 -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md0}
 	atf_check geli init -B none -P -K keyfile ${md1}
 	atf_check geli init -B none -P -K keyfile ${md2}
 	atf_check geli attach -p -k keyfile ${md0} ${md1} ${md2}
 	# verify that it did create all 3 geli devices
 	atf_check -s exit:0 test -c /dev/${md0}.eli
 	atf_check -s exit:0 test -c /dev/${md1}.eli
 	atf_check -s exit:0 test -c /dev/${md2}.eli
 }
 attach_multiple_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case nokey cleanup
 nokey_head()
 {
 	atf_set "descr" "geli attach fails if called with no key component"
 	atf_set "require.user" "root"
 }
 nokey_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check -s not-exit:0 -e match:"No key components given" \
 		geli attach -p ${md} 2>/dev/null
 }
 nokey_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case attach_d
 	atf_add_test_case attach_r
 	atf_add_test_case attach_multiple
 	atf_add_test_case nokey
 }
diff --git a/tests/sys/geom/class/eli/conf.sh b/tests/sys/geom/class/eli/conf.sh
index a21e645f1637..05ee4e9bb550 100644
--- a/tests/sys/geom/class/eli/conf.sh
+++ b/tests/sys/geom/class/eli/conf.sh
@@ -1,92 +1,94 @@
 #!/bin/sh
 
 class="eli"
 base=$(atf_get ident)
 MAX_SECSIZE=8192
 
 attach_md()
 {
-	local test_md
+	local _md
+	local rv=$1
+	shift
 
 	[ -c /dev/mdctl ] || atf_skip "no /dev/mdctl to create md devices"
-	test_md=$(mdconfig -a "$@") || atf_fail "failed to allocate md(4)"
-	echo $test_md >> $TEST_MDS_FILE || exit
-	echo $test_md
+	_md=$(mdconfig -a "$@") || atf_fail "failed to allocate md(4)"
+	echo $_md >> $TEST_MDS_FILE || exit
+	eval "${rv}='${_md}'"
 }
 
 # Execute `func` for each combination of cipher, sectorsize, and hmac algo
 # `func` usage should be:
 # func <cipher> <aalgo> <secsize>
 for_each_geli_config() {
 	func=$1
 	backing_filename=$2
 
 	# Double the sector size to allow for the HMACs' storage space.
 	osecsize=$(( $MAX_SECSIZE * 2 ))
 	# geli needs 512B for the label.
 	bytes=`expr $osecsize \* $sectors + 512`b
 
 	if [ -n "$backing_filename" ]; then
 		# Use a file-backed md(4) device, so we can deliberatly corrupt
 		# it without detaching the geli device first.
 		truncate -s $bytes backing_file
-		md=$(attach_md -t vnode -f backing_file)
+		attach_md md -t vnode -f backing_file
 	else
-		md=$(attach_md -t malloc -s $bytes)
+		attach_md md -t malloc -s $bytes
 	fi
 
 	for cipher in aes-xts:128 aes-xts:256 \
 	    aes-cbc:128 aes-cbc:192 aes-cbc:256 \
 	    camellia-cbc:128 camellia-cbc:192 camellia-cbc:256; do
 		ealgo=${cipher%%:*}
 		keylen=${cipher##*:}
 		for aalgo in hmac/sha1 hmac/ripemd160 hmac/sha256 \
 		    hmac/sha384 hmac/sha512; do
 			for secsize in 512 1024 2048 4096 $MAX_SECSIZE; do
 				${func} $cipher $aalgo $secsize
 				geli detach ${md} 2>/dev/null
 			done
 		done
 	done
 }
 
 # Execute `func` for each combination of cipher, and sectorsize, with no hmac
 # `func` usage should be:
 # func <cipher> <secsize>
 for_each_geli_config_nointegrity() {
 	func=$1
 
 	# geli needs 512B for the label.
 	bytes=`expr $MAX_SECSIZE \* $sectors + 512`b
-	md=$(attach_md -t malloc -s $bytes)
+	attach_md md -t malloc -s $bytes
 	for cipher in aes-xts:128 aes-xts:256 \
 	    aes-cbc:128 aes-cbc:192 aes-cbc:256 \
 	    camellia-cbc:128 camellia-cbc:192 camellia-cbc:256; do
 		ealgo=${cipher%%:*}
 		keylen=${cipher##*:}
 		for secsize in 512 1024 2048 4096 $MAX_SECSIZE; do
 			${func} $cipher $secsize
 			geli detach ${md} 2>/dev/null
 		done
 	done
 }
 
 geli_test_cleanup()
 {
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read md; do
 			[ -c /dev/${md}.eli ] && \
 				geli detach $md.eli 2>/dev/null
 			mdconfig -d -u $md 2>/dev/null
 		done < $TEST_MDS_FILE
 	fi
 	true
 }
 
 geli_test_setup()
 {
 	geom_atf_test_setup
 }
 
 ATF_TEST=true
 . `dirname $0`/../geom_subr.sh
diff --git a/tests/sys/geom/class/eli/configure_test.sh b/tests/sys/geom/class/eli/configure_test.sh
index 6814fde1c301..4185b68c13ec 100644
--- a/tests/sys/geom/class/eli/configure_test.sh
+++ b/tests/sys/geom/class/eli/configure_test.sh
@@ -1,59 +1,59 @@
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case configure_b_B cleanup
 configure_b_B_head()
 {
 	atf_set "descr" "geli configure -b will set the BOOT flag"
 	atf_set "require.user" "root"
 }
 configure_b_B_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check geli init -B none -P -K /dev/null ${md}
 
 	atf_check -s exit:0 -o match:'flags: 0x200$' geli dump ${md}
 
 	atf_check geli init -B none -b -P -K /dev/null ${md}
 
 	atf_check -s exit:0 -o match:'flags: 0x202$' geli dump ${md}
 
 	atf_check geli configure -B ${md}
 
 	atf_check -s exit:0 -o match:'flags: 0x200$' geli dump ${md}
 
 	atf_check geli configure -b ${md}
 
 	atf_check -s exit:0 -o match:'flags: 0x202$' geli dump ${md}
 
 	atf_check geli attach -p -k /dev/null ${md}
 
 	atf_check -s exit:0 -o match:'^Flags: .*BOOT' geli list ${md}.eli
 
 	atf_check geli configure -B ${md}
 
 	atf_check -o not-match:'^Flags: .*BOOT' geli list ${md}.eli
 
 	atf_check -s exit:0 -o match:'flags: 0x200$' geli dump ${md}
 
 	atf_check geli configure -b ${md}
 
 	atf_check -s exit:0 -o match:'^Flags: .*BOOT' geli list ${md}.eli
 
 	atf_check -s exit:0 -o match:'flags: 0x202$' geli dump ${md}
 
 	atf_check geli detach ${md}
 }
 configure_b_B_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case configure_b_B
 }
diff --git a/tests/sys/geom/class/eli/delkey_test.sh b/tests/sys/geom/class/eli/delkey_test.sh
index 374e14740580..2d03a6555ab3 100644
--- a/tests/sys/geom/class/eli/delkey_test.sh
+++ b/tests/sys/geom/class/eli/delkey_test.sh
@@ -1,113 +1,113 @@
 #!/bin/sh
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case delkey cleanup
 delkey_head()
 {
 	atf_set "descr" "geli delkey can destroy the master key"
 	atf_set "require.user" "root"
 }
 delkey_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile1 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile2 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile3 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile4 bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile1 ${md}
 	atf_check geli attach -p -k keyfile1 ${md}
 	atf_check -s exit:0 -o ignore geli setkey -n 1 -P -K keyfile2 ${md}
 
 	# Remove key 0 for attached provider.
 	atf_check geli delkey -n 0 ${md}
 	atf_check geli detach ${md}
 
 	# We cannot use keyfile1 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile1 ${md}
 
 	# Attach with key 1.
 	atf_check geli attach -p -k keyfile2 ${md}
 
 	# We cannot remove last key without -f option (for attached provider).
 	atf_check -s not-exit:0 -e match:"This is the last Master Key" \
 		geli delkey -n 1 ${md}
 
 	# Remove last key for attached provider.
 	atf_check geli delkey -f -n 1 ${md}
 
 	# If there are no valid keys, but provider is attached, we can save situation.
 	atf_check -s exit:0 -o ignore geli setkey -n 0 -P -K keyfile3 ${md}
 	atf_check geli detach ${md}
 
 	# We cannot use keyfile2 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile2 ${md}
 
 	# Attach with key 0.
 	atf_check geli attach -p -k keyfile3 ${md}
 
 	# Setup key 1.
 	atf_check -s exit:0 -o ignore geli setkey -n 1 -P -K keyfile4 ${md}
 	atf_check geli detach ${md}
 
 	# Remove key 1 for detached provider.
 	atf_check geli delkey -n 1 ${md}
 
 	# We cannot use keyfile4 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile4 ${md}
 
 	# We cannot remove last key without -f option (for detached provider).
 	atf_check -s not-exit:0 -e match:"This is the last Master Key" \
 		geli delkey -n 0 ${md}
 
 	# Remove last key for detached provider.
 	atf_check geli delkey -f -n 0 ${md}
 
 	# We cannot use keyfile3 anymore.
 	atf_check -s not-exit:0 -e match:"No valid keys" \
 		geli attach -p -k keyfile3 ${md}
 }
 delkey_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case delkey_readonly cleanup
 delkey_readonly_head()
 {
 	atf_set "descr" "geli delkey cannot work on a read-only provider"
 	atf_set "require.user" "root"
 }
 delkey_readonly_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check geli attach -r -p -k keyfile ${md}
 
 	atf_check -s not-exit:0 -e match:"read-only" geli delkey -n 0 ${md}
 	# Even with -f (force) it should still fail
 	atf_check -s not-exit:0 -e match:"read-only" geli delkey -f -n 0 ${md}
 }
 delkey_readonly_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case delkey
 	atf_add_test_case delkey_readonly
 }
diff --git a/tests/sys/geom/class/eli/detach_test.sh b/tests/sys/geom/class/eli/detach_test.sh
index c8952a0c739f..6acae8dea732 100644
--- a/tests/sys/geom/class/eli/detach_test.sh
+++ b/tests/sys/geom/class/eli/detach_test.sh
@@ -1,46 +1,46 @@
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case detach_l cleanup
 detach_l_head()
 {
 	atf_set "descr" "geli detach -l will cause a provider to detach on last close"
 	atf_set "require.user" "root"
 }
 detach_l_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check geli attach -p -k keyfile ${md}
 
 	# Be sure it doesn't detach before 'detach -l'.
 	atf_check dd if=/dev/${md}.eli of=/dev/null status=none
 	sleep 1
 	if [ ! -c /dev/${md}.eli ]; then
 		atf_fail "provider detached on last close without detach -l"
 	fi
 	atf_check geli detach -l ${md}
 	if [ ! -c /dev/${md}.eli ]; then
 		atf_fail "Provider detached before last close"
 	fi
 	atf_check dd if=/dev/${md}.eli of=/dev/null status=none
 	sleep 1
 	if [ -c /dev/${md}.eli ]; then
 		atf_fail "Provider did not detach on last close"
 	fi
 }
 detach_l_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case detach_l
 }
diff --git a/tests/sys/geom/class/eli/init_test.sh b/tests/sys/geom/class/eli/init_test.sh
index 8d4e9363ea05..534fc724d05d 100644
--- a/tests/sys/geom/class/eli/init_test.sh
+++ b/tests/sys/geom/class/eli/init_test.sh
@@ -1,379 +1,379 @@
 #!/bin/sh
 
 . $(atf_get_srcdir)/conf.sh
 
 init_test()
 {
 	cipher=$1
 	secsize=$2
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
 	atf_check -s exit:0 -e ignore \
 		geli init -B none -e $ealgo -l $keylen -P -K keyfile \
 		-s $secsize ${md}
 	atf_check geli attach -p -k keyfile ${md}
 
 	atf_check dd if=rnd of=/dev/${md}.eli bs=${secsize} count=${sectors} \
 		status=none
 
 	md_rnd=`dd if=rnd bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_ddev=`dd if=/dev/${md}.eli bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_edev=`dd if=/dev/${md} bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 
 	if [ ${md_rnd} != ${md_ddev} ]; then
 		atf_fail "Miscompare for ealgo=${ealgo} keylen=${keylen} sec=${secsize}"
 	fi
 	if [ ${md_rnd} == ${md_edev} ]; then
 		atf_fail "Data was not encrypted for ealgo=${ealgo} keylen=${keylen} sec=${secsize}"
 	fi
 }
 atf_test_case init cleanup
 init_head()
 {
 	atf_set "descr" "Basic I/O with geli"
 	atf_set "require.user" "root"
 	atf_set "timeout" 600
 }
 init_body()
 {
 	geli_test_setup
 
 	sectors=32
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=rnd bs=$MAX_SECSIZE count=${sectors} \
 		status=none
 	for_each_geli_config_nointegrity init_test
 }
 init_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case init_B cleanup
 init_B_head()
 {
 	atf_set "descr" "init -B can select an alternate backup metadata file"
 	atf_set "require.user" "root"
 }
 init_B_body()
 {
 	geli_test_setup
 
 	sectors=100
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
-	md=$(attach_md -t malloc -s $sectors)
+	attach_md md -t malloc -s $sectors
 
 	# -B none
 	rm -f /var/backups/${md}.eli
 	atf_check -s exit:0 -o ignore geli init -B none -P -K keyfile ${md}
 	if [ -f /var/backups/${md}.eli ]; then
 		atf_fail "geli created a backup file even with -B none"
 	fi
 
 	# no -B
 	rm -f /var/backups/${md}.eli
 	atf_check -s exit:0 -o ignore geli init -P -K keyfile ${md}
 	if [ ! -f /var/backups/${md}.eli ]; then
 		atf_fail "geli did not create a backup file"
 	fi
 	atf_check geli clear ${md}
 	atf_check -s not-exit:0 -e ignore geli attach -p -k keyfile ${md}
 	atf_check -s exit:0 -o ignore geli restore /var/backups/${md}.eli ${md}
 	atf_check -s exit:0 -o ignore geli attach -p -k keyfile ${md}
 	atf_check geli detach ${md}
 	rm -f /var/backups/${md}.eli
 
 	# -B file
 	rm -f backupfile
 	atf_check -s exit:0 -o ignore \
 		geli init -B backupfile -P -K keyfile ${md}
 	if [ ! -f backupfile ]; then
 		atf_fail "geli init -B did not create a backup file"
 	fi
 	atf_check geli clear ${md}
 	atf_check -s not-exit:0 -e ignore geli attach -p -k keyfile ${md}
 	atf_check geli restore backupfile ${md}
 	atf_check geli attach -p -k keyfile ${md}
 }
 init_B_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case init_J cleanup
 init_J_head()
 {
 	atf_set "descr" "init -J accepts a passfile"
 	atf_set "require.user" "root"
 }
 init_J_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile0 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile1 bs=512 count=16 status=none
 	dd if=/dev/random bs=512 count=16 status=none | sha1 > passfile0
 	atf_check_equal 0 $?
 	dd if=/dev/random bs=512 count=16 status=none | sha1 > passfile1
 	atf_check_equal 0 $?
 
 	for iter in -1 0 64; do
 		atf_check -s not-exit:0 -e ignore \
 			geli init -i ${iter} -B none -J passfile0 -P ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli init -i ${iter} -B none -J passfile0 -P -K keyfile0 ${md}
 		atf_check geli init -i ${iter} -B none -J passfile0 -K keyfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -p ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j keyfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k passfile0 -p ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j keyfile0 -k passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j keyfile0 -k keyfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j passfile0 -k passfile0 ${md}
 		atf_check -s exit:0 -e ignore \
 			geli attach -j passfile0 -k keyfile0 ${md}
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat keyfile0 | geli attach -j passfile0 -k - ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat passfile0 | geli attach -j - -k keyfile0 ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 
 		atf_check -s not-exit:0 -e ignore \
 			geli init -i ${iter} -B none -J passfile0 -J passfile1 -P ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli init -i ${iter} -B none -J passfile0 -J passfile1 -P -K keyfile0 -K keyfile1 ${md}
 		atf_check -s exit:0 -e ignore \
 			geli init -i ${iter} -B none -J passfile0 -J passfile1 -K keyfile0 -K keyfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -p ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -p ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -k keyfile1 -p ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -j passfile0 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -j passfile0 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -j passfile0 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -k keyfile1 -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -k keyfile1 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -k keyfile0 -j passfile0 -j passfile1 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile0 -k keyfile1 -j passfile1 -j passfile0 ${md}
 		atf_check -s not-exit:0 -e ignore \
 			geli attach -k keyfile1 -k keyfile0 -j passfile1 -j passfile0 ${md}
 		atf_check -s exit:0 -e ignore \
 			geli attach -j passfile0 -j passfile1 -k keyfile0 -k keyfile1 ${md}
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat passfile0 | geli attach -j - -j passfile1 -k keyfile0 -k keyfile1 ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat passfile1 | geli attach -j passfile0 -j - -k keyfile0 -k keyfile1 ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat keyfile0 | geli attach -j passfile0 -j passfile1 -k - -k keyfile1 ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat keyfile1 | geli attach -j passfile0 -j passfile1 -k keyfile0 -k - ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat keyfile0 keyfile1 | geli attach -j passfile0 -j passfile1 -k - ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 		atf_check -s exit:0 -e ignore -x \
 			"cat passfile0 passfile1 | awk '{printf \"%s\", \$0}' | geli attach -j - -k keyfile0 -k keyfile1 ${md}"
 		atf_check -s exit:0 -e ignore geli detach ${md}
 	done
 }
 init_J_cleanup()
 {
 	geli_test_cleanup
 }
 
 init_a_test()
 {
 	cipher=$1
 	aalgo=$2
 	secsize=$3
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
 	atf_check -s exit:0 -e ignore \
 		geli init -B none -a $aalgo -e $ealgo -l $keylen -P -K keyfile \
 		-s $secsize ${md}
 	atf_check geli attach -p -k keyfile ${md}
 
 	atf_check dd if=rnd of=/dev/${md}.eli bs=${secsize} count=${sectors} status=none
 
 	md_rnd=`dd if=rnd bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_ddev=`dd if=/dev/${md}.eli bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 
 	if [ ${md_rnd} != ${md_ddev} ]; then
 		atf_fail "Miscompare for aalgo=${aalgo} ealgo=${ealgo} keylen=${keylen} sec=${secsize}"
 	fi
 }
 atf_test_case init_a cleanup
 init_a_head()
 {
 	atf_set "descr" "I/O with geli and HMACs"
 	atf_set "require.user" "root"
 	atf_set "timeout" 3600
 }
 init_a_body()
 {
 	geli_test_setup
 
 	sectors=100
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=rnd bs=$MAX_SECSIZE count=${sectors} \
 		status=none
 	for_each_geli_config init_a_test
 	true
 }
 init_a_cleanup()
 {
 	geli_test_cleanup
 }
 
 init_alias_test() {
 	ealgo=$1
 	keylen=$2
 	expected_ealgo=$3
 	expected_keylen=$4
 
 	atf_check geli init -B none -e $ealgo -l $keylen -P -K keyfile ${md}
 	atf_check geli attach -p -k keyfile ${md}
 	real_ealgo=`geli list ${md}.eli | awk '/EncryptionAlgorithm/ {print $2}'`
 	real_keylen=`geli list ${md}.eli | awk '/KeyLength/ {print $2}'`
 
 	if [ "${real_ealgo}" != "${expected_ealgo}" ]; then
 		atf_fail "expected ${expected_ealgo} but got ${real_ealgo}"
 	fi
 
 	if [ "${real_keylen}" != "${expected_keylen}" ]; then
 		atf_fail "expected ${expected_keylen} but got ${real_keylen}"
 	fi
 	atf_check geli detach ${md}
 }
 atf_test_case init_alias cleanup
 init_alias_head()
 {
 	atf_set "descr" "geli init accepts cipher aliases"
 	atf_set "require.user" "root"
 }
 init_alias_body()
 {
 	geli_test_setup
 
-	md=$(attach_md -t malloc -s 1024k)
+	attach_md md -t malloc -s 1024k
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	for spec in aes:0:AES-XTS:128 aes:128:AES-XTS:128 aes:256:AES-XTS:256 \
 		camellia:0:CAMELLIA-CBC:128 camellia:128:CAMELLIA-CBC:128 \
 		camellia:256:CAMELLIA-CBC:256 ; do
 
 		ealgo=`echo $spec | cut -d : -f 1`
 		keylen=`echo $spec | cut -d : -f 2`
 		expected_ealgo=`echo $spec | cut -d : -f 3`
 		expected_keylen=`echo $spec | cut -d : -f 4`
 
 		init_alias_test $ealgo $keylen $expected_ealgo $expected_keylen
 	done
 }
 init_alias_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case init_i_P cleanup
 init_i_P_head()
 {
 	atf_set "descr" "geli: Options -i and -P are mutually exclusive"
 	atf_set "require.user" "root"
 }
 init_i_P_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check -s not-exit:0 -e "match:Options -i and -P are mutually exclusive"\
 		geli init -B none -i 64 -P -K keyfile $md
 }
 init_i_P_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case nokey cleanup
 nokey_head()
 {
 	atf_set "descr" "geli init fails if called with no key component"
 	atf_set "require.user" "root"
 }
 nokey_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check -s not-exit:0 -e match:"No key components given" \
 		geli init -B none -P ${md}
 }
 nokey_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case init
 	atf_add_test_case init_B
 	atf_add_test_case init_J
 	atf_add_test_case init_a
 	atf_add_test_case init_alias
 	atf_add_test_case init_i_P
 	atf_add_test_case nokey
 }
diff --git a/tests/sys/geom/class/eli/kill_test.sh b/tests/sys/geom/class/eli/kill_test.sh
index 422627f1f70c..eeaa440f11a9 100644
--- a/tests/sys/geom/class/eli/kill_test.sh
+++ b/tests/sys/geom/class/eli/kill_test.sh
@@ -1,101 +1,101 @@
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case kill cleanup
 kill_head()
 {
 	atf_set "descr" "geli kill will wipe a provider's metadata"
 	atf_set "require.user" "root"
 }
 kill_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=keyfile1 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile2 bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile1 ${md}
 	atf_check geli attach -p -k keyfile1 ${md}
 	atf_check -s exit:0 -o ignore geli setkey -n 1 -P -K keyfile2 ${md}
 
 	# Kill attached provider.
 	atf_check geli kill ${md}
 	sleep 1
 	# Provider should be automatically detached.
 	if [ -c /dev/${md}.eli ]; then
 		atf_fail "Provider did not detach when killed"
 	fi
 
 	# We cannot use keyfile1 anymore.
 	atf_check -s not-exit:0 -e match:"Cannot read metadata" \
 		geli attach -p -k keyfile1 ${md}
 
 	# We cannot use keyfile2 anymore.
 	atf_check -s not-exit:0 -e match:"Cannot read metadata" \
 		geli attach -p -k keyfile2 ${md}
 
 	atf_check geli init -B none -P -K keyfile1 ${md}
 	atf_check -s exit:0 -o ignore \
 		geli setkey -n 1 -p -k keyfile1 -P -K keyfile2 ${md}
 
 	# Should be possible to attach with keyfile1.
 	atf_check geli attach -p -k keyfile1 ${md}
 	atf_check geli detach ${md}
 
 	# Should be possible to attach with keyfile2.
 	atf_check geli attach -p -k keyfile2 ${md}
 	atf_check geli detach ${md}
 
 	# Kill detached provider.
 	atf_check geli kill ${md}
 
 	# We cannot use keyfile1 anymore.
 	atf_check -s not-exit:0 -e match:"Cannot read metadata" \
 		geli attach -p -k keyfile1 ${md}
 
 	# We cannot use keyfile2 anymore.
 	atf_check -s not-exit:0 -e match:"Cannot read metadata" \
 		geli attach -p -k keyfile2 ${md}
 }
 kill_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case kill_readonly cleanup
 kill_readonly_head()
 {
 	atf_set "descr" "geli kill will not destroy the keys of a readonly provider"
 	atf_set "require.user" "root"
 }
 kill_readonly_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	# Attach read-only
 	atf_check geli attach -r -p -k keyfile ${md}
 
 	atf_check geli kill ${md}
 	# The provider will be detached
 	atf_check [ ! -c /dev/${md}.eli ]
 	# But its keys should not be destroyed
 	atf_check geli attach -p -k keyfile ${md}
 }
 kill_readonly_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case kill
 	atf_add_test_case kill_readonly
 }
diff --git a/tests/sys/geom/class/eli/misc_test.sh b/tests/sys/geom/class/eli/misc_test.sh
index 2e1b1936f3a0..1cbeb0491ffd 100644
--- a/tests/sys/geom/class/eli/misc_test.sh
+++ b/tests/sys/geom/class/eli/misc_test.sh
@@ -1,206 +1,206 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2018 Alan Somers
 #
 # 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.
 #
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case preserve_props cleanup
 preserve_props_head()
 {
 	atf_set "descr" "geli should preserve basic GEOM properties"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 preserve_props_body()
 {
 	geli_test_setup
 
-	md=$(attach_md -s1m)
+	attach_md md -s1m
 	atf_check geli onetime /dev/${md}
 	md_secsize=$(diskinfo ${md} | cut -wf 2)
 	md_stripesize=$(diskinfo ${md} | cut -wf 5)
 	eli_secsize=$(diskinfo ${md}.eli | cut -wf 2)
 	eli_stripesize=$(diskinfo ${md}.eli | cut -wf 5)
 	atf_check_equal "$md_secsize" "$eli_secsize"
 	atf_check_equal "$md_stripesize" "$eli_stripesize"
 }
 preserve_props_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case preserve_disk_props cleanup
 preserve_disk_props_head()
 {
 	atf_set "descr" "geli should preserve properties for disks"
 	atf_set "require.user" "root"
 	atf_set "require.config" "disks"
 	atf_set "timeout" 15
 }
 preserve_disk_props_body()
 {
 	geli_test_setup
 
 	disks=`atf_config_get disks`
 	disk=${disks%% *}
 	if [ -z "$disk" ]; then
 		atf_skip "Must define disks (see tests(7))"
 	fi
 	atf_check geli onetime ${disk}
 
 	disk_ident=$(diskinfo -s ${disk})
 	disk_descr=$(diskinfo -v ${disk} | awk '/Disk descr/ {print $1}')
 	disk_rotrate=$(diskinfo -v ${disk} | awk '/Rotation rate/ {print $1}')
 	disk_zonemode=$(diskinfo -v ${disk} | awk '/Zone Mode/ {print $1}')
 	eli_ident=$(diskinfo -s ${disk}.eli)
 	eli_descr=$(diskinfo -v ${disk}.eli | awk '/Disk descr/ {print $1}')
 	eli_rotrate=$(diskinfo -v ${disk}.eli | awk '/Rotation/ {print $1}')
 	eli_zonemode=$(diskinfo -v ${disk}.eli | awk '/Zone Mode/ {print $1}')
 	atf_check_equal "$disk_ident" "$eli_ident"
 	atf_check_equal "$disk_descr" "$eli_descr"
 	atf_check_equal "$disk_rotrate" "$eli_rotrate"
 	atf_check_equal "$disk_zonemode" "$eli_zonemode"
 }
 preserve_disk_props_cleanup()
 {
 	disk_cleanup
 	geli_test_cleanup
 }
 
 atf_test_case physpath cleanup
 physpath_head()
 {
 	atf_set "descr" "geli should append /eli to the underlying device's physical path"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 physpath_body()
 {
 	geli_test_setup
 	if ! error_message=$(geom_load_class_if_needed nop); then
 		atf_skip "$error_message"
 	fi
 
-	md=$(attach_md -s1m)
+	attach_md md -s1m
 	# If the underlying device has no physical path, then geli should not
 	# create one.
 	atf_check -o empty -e ignore diskinfo -p $md
 	atf_check -s exit:0 geli onetime $md
 	atf_check -o empty -e ignore diskinfo -p $md.eli
 	atf_check -s exit:0 geli kill $md
 
 	# If the underlying device does have a physical path, then geli should
 	# append "/eli"
 	physpath="some/physical/path"
 	atf_check gnop create -z $physpath ${md}
 	atf_check -s exit:0 geli onetime $md.nop
 	atf_check -o match:"^${physpath}/eli$" diskinfo -p $md.nop.eli
 }
 physpath_cleanup()
 {
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read md; do
 			[ -c /dev/${md}.nop.eli ] && \
 				geli detach $md.nop.eli 2>/dev/null
 			[ -c /dev/${md}.nop ] && \
 				gnop destroy -f $md.nop 2>/dev/null
 			[ -c /dev/${md}.eli ] && \
 				geli detach $md.eli 2>/dev/null
 			mdconfig -d -u $md 2>/dev/null
 		done < $TEST_MDS_FILE
 	fi
 	true
 }
 
 unaligned_io_test()
 {
 	cipher=$1
 	secsize=$2
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
 	atf_check -s exit:0 -e ignore \
 		geli init -B none -e $ealgo -l $keylen -P -K keyfile \
 		-s $secsize ${md}
 	atf_check geli attach -p -k keyfile ${md}
 
 	atf_check $(atf_get_srcdir)/unaligned_io /dev/${md}.eli
 }
 
 atf_test_case unaligned_io cleanup
 unaligned_io_head()
 {
 	atf_set "descr" "regression test for PR 271766"
 	atf_set "require.user" "root"
 }
 unaligned_io_body()
 {
 	geli_test_setup
 
 	sectors=4
 
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 	for_each_geli_config_nointegrity unaligned_io_test
 }
 unaligned_io_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case physpath
 	atf_add_test_case preserve_props
 	atf_add_test_case preserve_disk_props
 	atf_add_test_case unaligned_io
 }
 
 common_cleanup()
 {
 	if [ -f "$MD_DEVS" ]; then
 		while read test_md; do
 			gnop destroy -f ${test_md}.nop 2>/dev/null
 			mdconfig -d -u $test_md 2>/dev/null
 		done < $MD_DEVS
 		rm $MD_DEVS
 	fi
 
 	if [ -f "$PLAINFILES" ]; then
 		while read f; do
 			rm -f ${f}
 		done < ${PLAINFILES}
 		rm ${PLAINFILES}
 	fi
 	true
 }
 
 disk_cleanup()
 {
 	disks=`atf_config_get disks`
 	disk=${disks%% *}
 	if [ -n "$disk" ]; then
 		geli kill ${disk} 2>/dev/null
 	fi
 }
diff --git a/tests/sys/geom/class/eli/onetime_test.sh b/tests/sys/geom/class/eli/onetime_test.sh
index 214533e1cb91..65306840384a 100644
--- a/tests/sys/geom/class/eli/onetime_test.sh
+++ b/tests/sys/geom/class/eli/onetime_test.sh
@@ -1,182 +1,182 @@
 
 . $(atf_get_srcdir)/conf.sh
 
 onetime_test()
 {
 	cipher=$1
 	secsize=$2
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
 	atf_check -s exit:0 -o ignore -e ignore \
 		geli onetime -e $ealgo -l $keylen -s $secsize ${md}
 
 	atf_check dd if=rnd of=/dev/${md}.eli bs=${secsize} count=${sectors} status=none
 
 	md_rnd=`dd if=rnd bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_ddev=`dd if=/dev/${md}.eli bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_edev=`dd if=/dev/${md} bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 
 	if [ ${md_rnd} != ${md_ddev} ]; then
 		atf_fail "geli did not return the original data"
 	fi
 	if [ ${md_rnd} == ${md_edev} ]; then
 		atf_fail "geli did not encrypt the data"
 	fi
 }
 atf_test_case onetime cleanup
 onetime_head()
 {
 	atf_set "descr" "geli onetime can create temporary providers"
 	atf_set "require.user" "root"
 	atf_set "timeout" 1800
 }
 onetime_body()
 {
 	geli_test_setup
 
 	sectors=100
 
 	dd if=/dev/random of=rnd bs=${MAX_SECSIZE} count=${sectors} status=none
 	for_each_geli_config_nointegrity onetime_test
 }
 onetime_cleanup()
 {
 	geli_test_cleanup
 }
 
 onetime_a_test()
 {
 	cipher=$1
 	aalgo=$2
 	secsize=$3
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
 	atf_check -s exit:0 -o ignore -e ignore \
 		geli onetime -a $aalgo -e $ealgo -l $keylen -s $secsize ${md}
 
 	atf_check dd if=rnd of=/dev/${md}.eli bs=${secsize} count=${sectors} status=none
 
 	md_rnd=`dd if=rnd bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_ddev=`dd if=/dev/${md}.eli bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 
 	if [ ${md_rnd} != ${md_ddev} ]; then
 		atf_fail "Miscompare for aalgo=${aalgo} ealgo=${ealgo} keylen=${keylen} sec=${secsize}"
 	fi
 }
 atf_test_case onetime_a cleanup
 onetime_a_head()
 {
 	atf_set "descr" "geli onetime with HMACs"
 	atf_set "require.user" "root"
 	atf_set "timeout" 1800
 }
 onetime_a_body()
 {
 	geli_test_setup
 
 	sectors=8
 
 	atf_check dd if=/dev/random of=rnd bs=$MAX_SECSIZE count=$sectors \
 		status=none
 	for_each_geli_config onetime_a_test
 }
 onetime_a_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case onetime_d cleanup
 onetime_d_head()
 {
 	atf_set "descr" "geli onetime -d will create providers that detach on last close"
 	atf_set "require.user" "root"
 }
 onetime_d_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s $sectors)
+	attach_md md -t malloc -s $sectors
 
 	atf_check geli onetime -d ${md}
 	if [ ! -c /dev/${md}.eli ]; then
 		atf_fail "Provider not created, or immediately detached"
 	fi
 
 	# Be sure it doesn't detach on read.
 	atf_check dd if=/dev/${md}.eli of=/dev/null status=none
 	sleep 1
 	if [ ! -c /dev/${md}.eli ]; then
 		atf_fail "Provider detached when a reader closed"
 	fi
 
 	# It should detach when a writer closes
 	true > /dev/${md}.eli
 	sleep 1
 	if [ -c /dev/${md}.eli ]; then
 		atf_fail "Provider didn't detach on last close of a writer"
 	fi
 }
 onetime_d_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case onetime_null cleanup
 onetime_null_head()
 {
 	atf_set "descr" "geli onetime can use the null cipher"
 	atf_set "require.user" "root"
 }
 onetime_null_body()
 {
 	geli_test_setup
 
 	sectors=100
 
 	dd if=/dev/random of=rnd bs=${MAX_SECSIZE} count=${sectors} status=none
 
 	secsize=512
 	ealgo=${cipher%%:*}
 	keylen=${cipher##*:}
 
-	md=$(attach_md -t malloc -s 100k)
+	attach_md md -t malloc -s 100k
 
 	atf_check -s exit:0 -o ignore -e ignore \
 		geli onetime -e null -s ${secsize} ${md}
 
 	atf_check dd if=rnd of=/dev/${md}.eli bs=${secsize} count=${sectors} status=none
 
 	md_rnd=`dd if=rnd bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_ddev=`dd if=/dev/${md}.eli bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	md_edev=`dd if=/dev/${md} bs=${secsize} count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 
 	if [ ${md_rnd} != ${md_ddev} ]; then
 		atf_fail "geli did not return the original data"
 	fi
 	if [ ${md_rnd} != ${md_edev} ]; then
 		atf_fail "geli encrypted the data even with the null cipher"
 	fi
 }
 onetime_null_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case onetime
 	atf_add_test_case onetime_a
 	atf_add_test_case onetime_d
 	atf_add_test_case onetime_null
 }
diff --git a/tests/sys/geom/class/eli/online_resize_test.sh b/tests/sys/geom/class/eli/online_resize_test.sh
index e137a7305122..ef6fe85c63d0 100755
--- a/tests/sys/geom/class/eli/online_resize_test.sh
+++ b/tests/sys/geom/class/eli/online_resize_test.sh
@@ -1,191 +1,191 @@
 #!/bin/sh
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case online_resize cleanup
 online_resize_head()
 {
 	atf_set "descr" "online resize of geli providers"
 	atf_set "require.user" "root"
 }
 online_resize_body()
 {
 	geli_test_setup
 
 	(
 		echo "m 512 none 10485248 1 1 20971008 1 1 31456768 1 1"
 		echo "m 4096 none 10481664 1 1 20967424 1 1 31453184 1 1"
 		echo "m 512 HMAC/SHA256 5242368 1 1 10485248 1 1 15728128 1 1"
 		echo "m 4096 HMAC/SHA256 9318400 1 1 18640896 1 1 27959296 1 1"
 		echo "p 512 none 11258999068425728 [0-9] 20971520 22517998136851968 [0-9] 41943040 33776997205278208 [0-9] 62914560"
 		echo "p 4096 none 11258999068422144 [0-9] 2621440 22517998136848384 [0-9] 5242880 33776997205274624 [0-9] 7864320"
 		echo "p 512 HMAC/SHA256 5629499534212608 [0-9] 20971520 11258999068425728 [0-9] 41943040 16888498602638848 [0-9] 62914560"
 		echo "p 4096 HMAC/SHA256 10007999171932160 [0-9] 20971520 20015998343868416 [0-9] 41943040 30023997515800576 [0-9] 62914560"
 	) | while read prefix sector auth esize10 ka10 kt10 esize20 ka20 kt20 esize30 ka30 kt30; do
 		if [ "${auth}" = "none" ]; then
 			aalgo=""
 			eflags="0x200"
 			dflags="0x0"
 		else
 			aalgo="-a ${auth}"
 			eflags="0x210"
 			dflags="0x10"
 		fi
 
 		if [ "${prefix}" = "m" ]; then
 			psize10="10485760"
 			psize20="20971520"
 			psize30="31457280"
 		else
 			psize10="11258999068426240"
 			psize20="22517998136852480"
 			psize30="33776997205278720"
 		fi
 
-		md=$(attach_md -t malloc -s40${prefix})
+		attach_md md -t malloc -s40${prefix}
 
 		# Initialise
 		atf_check -s exit:0 -o ignore gpart create -s GPT ${md}
 		atf_check -s exit:0 -o ignore gpart add -t freebsd-ufs -s 10${prefix} ${md}
 
 		echo secret >tmp.key
 
 		atf_check geli init ${aalgo} -s ${sector} -Bnone -PKtmp.key ${md}p1
 		# Autoresize is set by default.
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 
 		atf_check geli configure -R ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${dflags}$" geli dump ${md}p1
 		atf_check geli configure -r ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 
 		atf_check geli init -R ${aalgo} -s ${sector} -Bnone -PKtmp.key ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${dflags}$" geli dump ${md}p1
 
 		atf_check geli configure -r ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 		atf_check geli configure -R ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${dflags}$" geli dump ${md}p1
 
 		atf_check geli init ${aalgo} -s ${sector} -Bnone -PKtmp.key ${md}p1
 		atf_check geli attach -pk tmp.key ${md}p1
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check geli configure -R ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${dflags}$" geli dump ${md}p1
 		atf_check -o not-match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check geli configure -r ${md}p1
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 
 		atf_check geli configure -R ${md}p1
 		atf_check -s exit:0 -o match:"provsize: ${psize10}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		# Autoresize turned off - we lose metadata.
 		atf_check -s exit:1 -o empty -e ignore geli dump ${md}p1
 		atf_check geli detach ${md}p1.eli
 		# When we recover previous size, the metadata should be there.
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 10${prefix} ${md}
 		atf_check -s exit:0 -o match:"flags: ${dflags}$" geli dump ${md}p1
 
 		atf_check geli configure -r ${md}p1
 		atf_check geli attach -pk tmp.key ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${esize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysAllocated: ${ka10}$" geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysTotal: ${kt10}$" geli list ${md}p1.eli
 
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		atf_check -s exit:0 -o match:"provsize: ${psize20}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${esize20}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysAllocated: ${ka20}$" geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysTotal: ${kt20}$" geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		if [ "${prefix}" = "m" ]; then
 			atf_check -s exit:1 -o empty -e match:"^${esize20} bytes transferred " dd if=/dev/random of=/dev/${md}p1.eli bs=1m
 			atf_check -s exit:0 -o empty -e match:"^${esize20} bytes transferred " dd if=/dev/${md}p1.eli of=/dev/null bs=1m
 		fi
 
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 30${prefix} ${md}
 		atf_check -s exit:0 -o match:"provsize: ${psize30}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${esize30}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysAllocated: ${ka30}$" geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:"^KeysTotal: ${kt30}$" geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:"flags: ${eflags}$" geli dump ${md}p1
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		if [ "${prefix}" = "m" ]; then
 			atf_check -s exit:1 -o empty -e match:"^${esize30} bytes transferred " dd if=/dev/random of=/dev/${md}p1.eli bs=1m
 			atf_check -s exit:0 -o empty -e match:"^${esize30} bytes transferred " dd if=/dev/${md}p1.eli of=/dev/null bs=1m
 		fi
 
 		atf_check geli detach ${md}p1.eli
 
 		# Make sure that the old metadata is removed.
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		atf_check -s exit:1 -o empty -e ignore geli dump ${md}p1
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 10${prefix} ${md}
 		atf_check -s exit:1 -o empty -e ignore geli dump ${md}p1
 
 		# Test geli with onetime keys.
 		if [ "${auth}" = "none" ]; then
 			osize10="${psize10}"
 			osize20="${psize20}"
 			osize30="${psize30}"
 		else
 			osize10="${esize10}"
 			osize20="${esize20}"
 			osize30="${esize30}"
 			if [ "${sector}" -eq 512 ]; then
 				osize10=$((osize10+sector))
 				osize20=$((osize20+sector))
 				osize30=$((osize30+sector))
 			fi
 		fi
 		atf_check geli onetime ${aalgo} -s ${sector} ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize20}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 30${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize30}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check geli detach ${md}p1.eli
 
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 10${prefix} ${md}
 		atf_check geli onetime -R ${aalgo} -s ${sector} ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -o not-match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 30${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check geli detach ${md}p1.eli
 
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 10${prefix} ${md}
 		atf_check geli onetime ${aalgo} -s ${sector} ${md}p1
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check geli configure -R ${md}p1
 		atf_check -o not-match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 20${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize10}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 		atf_check geli configure -r ${md}p1
 		atf_check -s exit:0 -o match:'^Flags: .*AUTORESIZE' geli list ${md}p1.eli
 		atf_check -s exit:0 -o match:resized gpart resize -i 1 -s 30${prefix} ${md}
 		atf_check -s exit:0 -o match:"^[[:space:]]${osize30}[[:space:]]+# mediasize in bytes" diskinfo -v ${md}p1.eli
 	done
 }
 online_resize_cleanup()
 {
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read md; do
 			atf_check -s ignore -e ignore -o ignore geli detach ${md}p1.eli
 			atf_check -s ignore -e ignore -o ignore gpart delete -i 1 ${md}
 			atf_check -s ignore -e ignore -o ignore gpart destroy ${md}
 		done < $TEST_MDS_FILE
 	fi
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case online_resize
 }
diff --git a/tests/sys/geom/class/eli/resize_test.sh b/tests/sys/geom/class/eli/resize_test.sh
index c6f9e459e934..832bfeee5c92 100644
--- a/tests/sys/geom/class/eli/resize_test.sh
+++ b/tests/sys/geom/class/eli/resize_test.sh
@@ -1,88 +1,88 @@
 #!/bin/sh
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case resize cleanup
 resize_head()
 {
 	atf_set "descr" "geli resize will resize a geli provider"
 	atf_set "require.user" "root"
 }
 resize_body()
 {
 	geli_test_setup
 
 	BLK=512
 	BLKS_PER_MB=2048
 
-	md=$(attach_md -t malloc -s40m)
+	attach_md md -t malloc -s40m
 
 	# Initialise
 	atf_check -s exit:0 -o ignore gpart create -s BSD ${md}
 	atf_check -s exit:0 -o ignore gpart add -t freebsd-ufs -s 10m ${md}
 
 	echo secret >tmp.key
 	atf_check geli init -Bnone -PKtmp.key ${md}a
 	atf_check geli attach -pk tmp.key ${md}a
 
 	atf_check -s exit:0 -o ignore newfs -U ${md}a.eli
 	atf_check -s exit:7 -o ignore fsck_ffs -Ffy ${md}a.eli
 
 	# Doing a backup, resize & restore must be forced (with -f) as geli
 	# verifies that the provider size in the metadata matches the consumer.
 
 	atf_check geli backup ${md}a tmp.meta
 	atf_check geli detach ${md}a.eli
 	atf_check -s exit:0 -o match:resized gpart resize -i1 -s 20m ${md}
 	atf_check -s not-exit:0 -e ignore geli attach -pktmp.key ${md}a
 	atf_check -s not-exit:0 -e ignore geli restore tmp.meta ${md}a
 	atf_check geli restore -f tmp.meta ${md}a
 	atf_check geli attach -pktmp.key ${md}a
 	atf_check -s exit:0 -o ignore growfs -y ${md}a.eli
 	atf_check -s exit:7 -o ignore fsck_ffs -Ffy ${md}a.eli
 
 	# Now do the resize properly
 
 	atf_check geli detach ${md}a.eli
 	atf_check -s exit:0 -o match:resized gpart resize -i1 -s 30m ${md}
 	atf_check geli resize -s20m ${md}a
 	atf_check -s not-exit:0 -e match:"Inconsistent provider.*metadata" \
 		geli resize -s20m ${md}a
 	atf_check geli attach -pktmp.key ${md}a
 	atf_check -s exit:0 -o ignore growfs -y ${md}a.eli
 	atf_check -s exit:7 -o ignore fsck_ffs -Ffy ${md}a.eli
 
 	atf_check geli detach ${md}a.eli
 	atf_check -s exit:0 -o ignore gpart destroy -F $md
 
 
 	# Verify that the man page example works, changing ada0 to $md,
 	# 1g to 20m, 2g to 30m and keyfile to tmp.key, and adding -B none
 	# to geli init.
 
 	atf_check -s exit:0 -o ignore gpart create -s GPT $md
 	atf_check -s exit:0 -o ignore gpart add -s 20m -t freebsd-ufs -i 1 $md
 	atf_check geli init -B none -K tmp.key -P ${md}p1
 	atf_check -s exit:0 -o match:resized gpart resize -s 30m -i 1 $md
 	atf_check geli resize -s 20m ${md}p1
 	atf_check geli attach -k tmp.key -p ${md}p1
 }
 resize_cleanup()
 {
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read md; do
 			[ -c /dev/${md}a.eli ] && \
 				geli detach ${md}a.eli 2>/dev/null
 			[ -c /dev/${md}p1.eli ] && \
 				geli detach ${md}p1.eli
 			[ -c /dev/${md}.eli ] && \
 				geli detach ${md}.eli 2>/dev/null
 			mdconfig -d -u $md 2>/dev/null
 		done < $TEST_MDS_FILE
 	fi
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case resize
 }
diff --git a/tests/sys/geom/class/eli/setkey_test.sh b/tests/sys/geom/class/eli/setkey_test.sh
index 34fb8221ab04..92387a8a8ab6 100644
--- a/tests/sys/geom/class/eli/setkey_test.sh
+++ b/tests/sys/geom/class/eli/setkey_test.sh
@@ -1,221 +1,221 @@
 #!/bin/sh
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case setkey cleanup
 setkey_head()
 {
 	atf_set "descr" "geli setkey can change the key for an existing provider"
 	atf_set "require.user" "root"
 }
 setkey_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=rnd bs=512 count=${sectors} status=none
 	hash1=`dd if=rnd bs=512 count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	atf_check dd if=/dev/random of=keyfile1 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile2 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile3 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile4 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile5 bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile1 ${md}
 	atf_check geli attach -p -k keyfile1 ${md}
 
 	atf_check \
 		dd if=rnd of=/dev/${md}.eli bs=512 count=${sectors} status=none
 	hash2=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 
 	# Change current key (0) for attached provider.
 	atf_check -s exit:0 -o ignore geli setkey -P -K keyfile2 ${md}
 	atf_check geli detach ${md}
 
 	# We cannot use keyfile1 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile1 ${md}
 
 	# Attach with new key.
 	atf_check geli attach -p -k keyfile2 ${md}
 	hash3=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 
 	# Change key 1 for attached provider.
 	atf_check -s exit:0 -o ignore geli setkey -n 1 -P -K keyfile3 ${md}
 	atf_check geli detach ${md}
 
 	# Attach with key 1.
 	atf_check geli attach -p -k keyfile3 ${md}
 	hash4=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 	atf_check geli detach ${md}
 
 	# Change current (1) key for detached provider.
 	atf_check -s exit:0 -o ignore geli setkey -p -k keyfile3 -P -K keyfile4 ${md}
 
 	# We cannot use keyfile3 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile3 ${md}
 
 	# Attach with key 1.
 	atf_check geli attach -p -k keyfile4 ${md}
 	hash5=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 	atf_check geli detach ${md}
 
 	# Change key 0 for detached provider.
 	atf_check -s exit:0 -o ignore geli setkey -n 0 -p -k keyfile4 -P -K keyfile5 ${md}
 
 	# We cannot use keyfile2 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -p -k keyfile2 ${md} 2>/dev/null
 
 	# Attach with key 0.
 	atf_check geli attach -p -k keyfile5 ${md}
 	hash6=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 	atf_check geli detach ${md}
 
 	atf_check_equal ${hash1} ${hash2}
 	atf_check_equal ${hash1} ${hash3}
 	atf_check_equal ${hash1} ${hash4}
 	atf_check_equal ${hash1} ${hash5}
 	atf_check_equal ${hash1} ${hash6}
 }
 setkey_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case setkey_passphrase cleanup
 setkey_passphrase_head()
 {
 	atf_set "descr" "geli setkey can change the passphrase for a provider"
 	atf_set "require.user" "root"
 }
 setkey_passphrase_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 
 	atf_check dd if=/dev/random of=rnd bs=512 count=${sectors} status=none
 	hash1=`dd if=rnd bs=512 count=${sectors} status=none | md5`
 	atf_check_equal 0 $?
 	atf_check dd if=/dev/random of=pass1 bs=512 count=1 status=none
 	atf_check dd if=/dev/random of=pass2 bs=512 count=1 status=none
 	atf_check dd if=/dev/random of=pass3 bs=512 count=1 status=none
 
 	atf_check geli init -B none -J pass1 ${md}
 	atf_check geli attach -j pass1 ${md}
 
 	atf_check \
 		dd if=rnd of=/dev/${md}.eli bs=512 count=${sectors} status=none
 	hash2=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check_equal 0 $?
 
 	atf_check geli detach ${md}
 
 	# Change from passphrase 1 to passphrase 2 for the detached provider.
 	atf_check -s exit:0 -o ignore geli setkey -j pass1 -J pass2 ${md}
 
 	# Make sure that we can attach with passphrase 2 but not with
 	# passphrase 1.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -j pass1 ${md}
 	atf_check -s exit:0 geli attach -j pass2 ${md}
 	hash3=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 
 	# Change from passphrase 2 to passphrase 3 for the attached provider.
 	atf_check -s exit:0 -o ignore geli setkey -j pass2 -J pass3 ${md}
 	hash4=`dd if=/dev/${md}.eli bs=512 count=${sectors} 2>/dev/null | md5`
 	atf_check geli detach ${md}
 
         # Make sure that we cannot attach with passphrase 2 anymore.
 	atf_check -s not-exit:0 -e match:"Wrong key" \
 		geli attach -j pass2 ${md}
 
 	atf_check_equal ${hash1} ${hash2}
 	atf_check_equal ${hash1} ${hash3}
 	atf_check_equal ${hash1} ${hash4}
 }
 setkey_passphrase_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case setkey_readonly cleanup
 setkey_readonly_head()
 {
 	atf_set "descr" "geli setkey cannot change the keys of a readonly provider"
 	atf_set "require.user" "root"
 }
 setkey_readonly_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile ${md}
 	atf_check geli attach -r -p -k keyfile ${md}
 
 	atf_check -s not-exit:0 -e match:"read-only" \
 		geli setkey -n 1 -P -K /dev/null ${md}
 }
 setkey_readonly_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_test_case nokey cleanup
 nokey_head()
 {
 	atf_set "descr" "geli setkey can change the key for an existing provider"
 	atf_set "require.user" "root"
 }
 nokey_body()
 {
 	geli_test_setup
 
 	sectors=100
-	md=$(attach_md -t malloc -s `expr $sectors + 1`)
+	attach_md md -t malloc -s `expr $sectors + 1`
 	atf_check dd if=/dev/random of=keyfile1 bs=512 count=16 status=none
 	atf_check dd if=/dev/random of=keyfile2 bs=512 count=16 status=none
 
 	atf_check geli init -B none -P -K keyfile1 ${md}
 
 	# Try to set the key for a detached device without providing any
 	# components for the old key.
 	atf_check -s not-exit:0 -e match:"No key components given" \
 		geli setkey -n 0 -p -P -K keyfile2 ${md}
 
 	# Try to set the key for a detached device without providing any
 	# components for the new key
 	atf_check -s not-exit:0 -e match:"No key components given" \
 		geli setkey -n 0 -p -k keyfile1 -P ${md}
 
 	# Try to set a new key for an attached device with no components
 	atf_check geli attach -p -k keyfile1 ${md}
 	atf_check -s not-exit:0 -e match:"No key components given" \
 		geli setkey -n 0 -P ${md}
 }
 nokey_cleanup()
 {
 	geli_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case setkey
 	atf_add_test_case setkey_passphrase
 	atf_add_test_case setkey_readonly
 	atf_add_test_case nokey
 }
diff --git a/tests/sys/geom/class/geom_subr.sh b/tests/sys/geom/class/geom_subr.sh
index f8eca4c6b220..8e3b12d5f620 100644
--- a/tests/sys/geom/class/geom_subr.sh
+++ b/tests/sys/geom/class/geom_subr.sh
@@ -1,81 +1,83 @@
 #!/bin/sh
 
 TEST_MDS_FILE="${TMPDIR}/test_mds.$(basename $0)"
 
 devwait()
 {
 	while :; do
 		if [ -c /dev/${class}/${name} ]; then
 			return
 		fi
 		sleep 0.2
 	done
 }
 
 attach_md()
 {
-	local test_md
+	local _md
+	local rv=$1
+	shift
 
 	[ -c /dev/mdctl ] || atf_skip "no /dev/mdctl to create md devices"
-	test_md=$(mdconfig -a "$@") || exit
-	echo $test_md >> $TEST_MDS_FILE || exit
-	echo $test_md
+	_md=$(mdconfig -a "$@") || exit
+	echo $_md >> $TEST_MDS_FILE || exit
+	eval "${rv}='${_md}'"
 }
 
 detach_md()
 {
 	local test_md unit
 
 	test_md=$1
 	unit=${test_md#md}
 	mdconfig -d -u $unit || exit
 	sed -i '' "/^${test_md}$/d" $TEST_MDS_FILE || exit
 }
 
 geom_test_cleanup()
 {
 	local test_md
 
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read test_md; do
 			# The "#" tells the TAP parser this is a comment
 			echo "# Removing test memory disk: $test_md"
 			mdconfig -d -u $test_md
 		done < $TEST_MDS_FILE
 		rm -f "$TEST_MDS_FILE"
 	fi
 }
 
 geom_load_class_if_needed()
 {
 	local class=$1
 
 	# If the geom class isn't already loaded, try loading it.
 	if ! kldstat -q -m g_${class}; then
 		if ! geom ${class} load; then
 			echo "could not load module for geom class=${class}"
 			return 1
 		fi
 	fi
 	return 0
 }
 
 geom_atf_test_setup()
 {
 	if ! error_message=$(geom_load_class_if_needed $class); then
 		atf_skip "$error_message"
 	fi
 }
 
 geom_tap_test_setup()
 {
 	if ! error_message=$(geom_load_class_if_needed $class); then
 		echo "1..0 # SKIP $error_message"
 		exit 0
 	fi
 }
 
 : ${ATF_TEST=false}
 if ! $ATF_TEST; then
 	geom_tap_test_setup
 fi
diff --git a/tests/sys/geom/class/mirror/10_test.sh b/tests/sys/geom/class/mirror/10_test.sh
index 775eb7f99591..351689d1e185 100644
--- a/tests/sys/geom/class/mirror/10_test.sh
+++ b/tests/sys/geom/class/mirror/10_test.sh
@@ -1,68 +1,68 @@
 #!/bin/sh
 
 # Test handling of read errors.
 
 . $(dirname $0)/conf.sh
 
 echo 1..3
 
 set -e
 
 ddbs=2048
 regreadfp="debug.fail_point.g_mirror_regular_request_read"
 m1=$(mktemp $base.XXXXXX)
 m2=$(mktemp $base.XXXXXX)
 
 dd if=/dev/random of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 
-us0=$(attach_md -t vnode -f $m1)
-us1=$(attach_md -t vnode -f $m2)
+attach_md us0 -t vnode -f $m1
+attach_md us1 -t vnode -f $m2
 
 gmirror label $name /dev/$us0
 gmirror insert $name /dev/$us1
 devwait
 syncwait
 
 tmp1=$(mktemp $base.XXXXXX)
 tmp2=$(mktemp $base.XXXXXX)
 
 EIO=5
 # gmirror should retry a failed read from the other mirror.
 sysctl ${regreadfp}="1*return(${EIO})[pid $(gmirror_worker_pid)]"
 dd if=/dev/mirror/$name of=$tmp1 iseek=256 bs=$ddbs count=1 >/dev/null 2>&1
 dd if=/dev/$us1 of=$tmp2 iseek=256 bs=$ddbs count=1 >/dev/null 2>&1
 sysctl ${regreadfp}='off'
 
 if cmp -s $tmp1 $tmp2; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 # Make sure that one of the mirrors was marked broken.
 genid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*genid: /{print $2}')
 genid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*genid: /{print $2}')
 if [ $genid1 -eq $(($genid2 + 1)) -o $genid2 -eq $(($genid1 + 1)) ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
 
 # Force a retaste of the disconnected component.
 if [ $(gmirror status -s $name | awk '{print $3}') = $us0 ]; then
 	detach_md $us1
-	us1=$(attach_md -t vnode -f $m2)
+	attach_md us1 -t vnode -f $m2
 else
 	detach_md $us0
-	us0=$(attach_md -t vnode -f $m1)
+	attach_md us0 -t vnode -f $m1
 fi
 
 # Make sure that the component wasn't re-added to the gmirror.
 if [ $(gmirror status -s $name | wc -l) -eq 1 ]; then
 	echo "ok 3"
 else
 	echo "not ok 3"
 fi
 
 rm -f $m1 $m2 $tmp1 $tmp2
diff --git a/tests/sys/geom/class/mirror/11_test.sh b/tests/sys/geom/class/mirror/11_test.sh
index 7d4324e383e9..0e498ae03d15 100644
--- a/tests/sys/geom/class/mirror/11_test.sh
+++ b/tests/sys/geom/class/mirror/11_test.sh
@@ -1,83 +1,83 @@
 #!/bin/sh
 
 # Test handling of read errors.
 
 . $(dirname $0)/conf.sh
 
 echo 1..4
 
 set -e
 
 ddbs=2048
 regreadfp="debug.fail_point.g_mirror_regular_request_read"
 m1=$(mktemp $base.XXXXXX)
 m2=$(mktemp $base.XXXXXX)
 
 dd if=/dev/random of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 
-us0=$(attach_md -t vnode -f $m1)
-us1=$(attach_md -t vnode -f $m2)
+attach_md us0 -t vnode -f $m1
+attach_md us1 -t vnode -f $m2
 
 gmirror label $name /dev/$us0
 gmirror insert $name /dev/$us1
 devwait
 syncwait
 
 tmp1=$(mktemp $base.XXXXXX)
 tmp2=$(mktemp $base.XXXXXX)
 
 ENXIO=6
 # gmirror has special handling for ENXIO. It does not mark the failed component
 # as broken, allowing it to rejoin the mirror automatically when it appears.
 sysctl ${regreadfp}="1*return(${ENXIO})[pid $(gmirror_worker_pid)]"
 dd if=/dev/mirror/$name of=$tmp1 iseek=512 bs=$ddbs count=1 >/dev/null 2>&1
 dd if=/dev/$us1 of=$tmp2 iseek=512 bs=$ddbs count=1 >/dev/null 2>&1
 sysctl ${regreadfp}='off'
 
 if cmp -s $tmp1 $tmp2; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 # Verify that the genids still match after ENXIO.
 genid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*genid: /{print $2}')
 genid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*genid: /{print $2}')
 if [ $genid1 -eq $genid2 ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
 
 # Trigger a syncid bump.
 dd if=/dev/zero of=/dev/mirror/$name bs=$ddbs count=1 >/dev/null 2>&1
 
 # The ENXIO+write should have caused a syncid bump.
 syncid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*syncid: /{print $2}')
 syncid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*syncid: /{print $2}')
 if [ $syncid1 -eq $(($syncid2 + 1)) -o $syncid2 -eq $(($syncid1 + 1)) ]; then
 	echo "ok 3"
 else
 	echo "not ok 3"
 fi
 
 # Force a retaste of the disconnected component.
 if [ $(gmirror status -s $name | awk '{print $3}') = $us0 ]; then
 	detach_md $us1
-	us1=$(attach_md -t vnode -f $m2)
+	attach_md us1 -t vnode -f $m2
 else
 	detach_md $us0
-	us0=$(attach_md -t vnode -f $m1)
+	attach_md us0 -t vnode -f $m1
 fi
 
 # Make sure that the retaste caused the mirror to automatically be re-added.
 if [ $(gmirror status -s $name | wc -l) -eq 2 ]; then
 	echo "ok 4"
 else
 	echo "not ok 4"
 fi
 
 syncwait
 
 rm -f $m1 $m2 $tmp1 $tmp2
diff --git a/tests/sys/geom/class/mirror/12_test.sh b/tests/sys/geom/class/mirror/12_test.sh
index 36132269bc81..4f24dd081fef 100644
--- a/tests/sys/geom/class/mirror/12_test.sh
+++ b/tests/sys/geom/class/mirror/12_test.sh
@@ -1,67 +1,67 @@
 #!/bin/sh
 
 # Test handling of write errors.
 
 . $(dirname $0)/conf.sh
 
 echo 1..3
 
 set -e
 
 ddbs=2048
 regwritefp="debug.fail_point.g_mirror_regular_request_write"
 m1=$(mktemp $base.XXXXXX)
 m2=$(mktemp $base.XXXXXX)
 
 dd if=/dev/zero of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 
-us0=$(attach_md -t vnode -f $m1)
-us1=$(attach_md -t vnode -f $m2)
+attach_md us0 -t vnode -f $m1
+attach_md us1 -t vnode -f $m2
 
 gmirror label $name /dev/$us0 /dev/$us1
 devwait
 
 tmp1=$(mktemp $base.XXXXXX)
 tmp2=$(mktemp $base.XXXXXX)
 dd if=/dev/random of=$tmp1 bs=$ddbs count=1 >/dev/null 2>&1
 
 EIO=5
 # gmirror should kick one of the mirrors out after hitting EIO.
 sysctl ${regwritefp}="1*return(${EIO})[pid $(gmirror_worker_pid)]"
 dd if=$tmp1 of=/dev/mirror/$name bs=$ddbs count=1 >/dev/null 2>&1
 dd if=/dev/mirror/$name of=$tmp2 bs=$ddbs count=1 >/dev/null 2>&1
 sysctl ${regwritefp}='off'
 
 if cmp -s $tmp1 $tmp2; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 # Make sure that one of the mirrors was marked broken.
 genid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*genid: /{print $2}')
 genid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*genid: /{print $2}')
 if [ $genid1 -eq $(($genid2 + 1)) -o $genid2 -eq $(($genid1 + 1)) ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
 
 # Force a retaste of the disconnected component.
 if [ $(gmirror status -s $name | awk '{print $3}') = $us0 ]; then
 	detach_md $us1
-	us1=$(attach_md -t vnode -f $m2)
+	attach_md us1 -t vnode -f $m2
 else
 	detach_md $us0
-	us0=$(attach_md -t vnode -f $m1)
+	attach_md us0 -t vnode -f $m1
 fi
 
 # Make sure that the component wasn't re-added to the gmirror.
 if [ $(gmirror status -s $name | wc -l) -eq 1 ]; then
 	echo "ok 3"
 else
 	echo "not ok 3"
 fi
 
 rm -f $m1 $m2 $tmp1 $tmp2
diff --git a/tests/sys/geom/class/mirror/13_test.sh b/tests/sys/geom/class/mirror/13_test.sh
index 1ff004e3ba54..c312a1b7a795 100644
--- a/tests/sys/geom/class/mirror/13_test.sh
+++ b/tests/sys/geom/class/mirror/13_test.sh
@@ -1,80 +1,80 @@
 #!/bin/sh
 
 # Test handling of write errors.
 
 . $(dirname $0)/conf.sh
 
 echo 1..4
 
 set -e
 
 ddbs=2048
 regwritefp="debug.fail_point.g_mirror_regular_request_write"
 m1=$(mktemp $base.XXXXXX)
 m2=$(mktemp $base.XXXXXX)
 
 dd if=/dev/random of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 
-us0=$(attach_md -t vnode -f $m1)
-us1=$(attach_md -t vnode -f $m2)
+attach_md us0 -t vnode -f $m1
+attach_md us1 -t vnode -f $m2
 
 gmirror label $name /dev/$us0 /dev/$us1
 devwait
 
 tmp1=$(mktemp $base.XXXXXX)
 tmp2=$(mktemp $base.XXXXXX)
 
 dd if=/dev/random of=$tmp1 bs=$ddbs count=1 >/dev/null 2>&1
 
 ENXIO=6
 # gmirror has special handling for ENXIO. It does not mark the failed component
 # as broken, allowing it to rejoin the mirror automatically when it appears.
 sysctl ${regwritefp}="1*return(${ENXIO})[pid $(gmirror_worker_pid)]"
 dd if=$tmp1 of=/dev/mirror/$name bs=$ddbs count=1 >/dev/null 2>&1
 dd if=/dev/mirror/$name of=$tmp2 bs=$ddbs count=1 >/dev/null 2>&1
 sysctl ${regwritefp}='off'
 
 if cmp -s $tmp1 $tmp2; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 # Verify that the genids still match after ENXIO.
 genid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*genid: /{print $2}')
 genid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*genid: /{print $2}')
 if [ $genid1 -eq $genid2 ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
 
 # The ENXIO should have caused a syncid bump.
 syncid1=$(gmirror dump /dev/$us0 | awk '/^[[:space:]]*syncid: /{print $2}')
 syncid2=$(gmirror dump /dev/$us1 | awk '/^[[:space:]]*syncid: /{print $2}')
 if [ $syncid1 -eq $(($syncid2 + 1)) -o $syncid2 -eq $(($syncid1 + 1)) ]; then
 	echo "ok 3"
 else
 	echo "not ok 3"
 fi
 
 # Force a retaste of the disconnected component.
 if [ $(gmirror status -s $name | awk '{print $3}') = $us0 ]; then
 	detach_md $us1
-	us1=$(attach_md -t vnode -f $m2)
+	attach_md us1 -t vnode -f $m2
 else
 	detach_md $us0
-	us0=$(attach_md -t vnode -f $m1)
+	attach_md us0 -t vnode -f $m1
 fi
 
 # Make sure that the retaste caused the mirror to automatically be re-added.
 if [ $(gmirror status -s $name | wc -l) -eq 2 ]; then
 	echo "ok 4"
 else
 	echo "not ok 4"
 fi
 
 syncwait
 
 rm -f $m1 $m2 $tmp1 $tmp2
diff --git a/tests/sys/geom/class/mirror/1_test.sh b/tests/sys/geom/class/mirror/1_test.sh
index bcd903e0d3f8..929aa1c6ddcf 100644
--- a/tests/sys/geom/class/mirror/1_test.sh
+++ b/tests/sys/geom/class/mirror/1_test.sh
@@ -1,22 +1,22 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 gmirror label $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 # Size of created device should be 1MB - 512b.
 
 size=`diskinfo /dev/mirror/${name} | awk '{print $3}'`
 
 if [ $size -eq 1048064 ]; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
diff --git a/tests/sys/geom/class/mirror/2_test.sh b/tests/sys/geom/class/mirror/2_test.sh
index 7bb813502047..31bb426d05d7 100644
--- a/tests/sys/geom/class/mirror/2_test.sh
+++ b/tests/sys/geom/class/mirror/2_test.sh
@@ -1,51 +1,51 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..4"
 
 balance="round-robin"
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 dd if=/dev/${us0} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 dd if=/dev/${us1} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 dd if=/dev/${us2} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/3_test.sh b/tests/sys/geom/class/mirror/3_test.sh
index 83993d32df2f..dd2ca8f028fd 100644
--- a/tests/sys/geom/class/mirror/3_test.sh
+++ b/tests/sys/geom/class/mirror/3_test.sh
@@ -1,63 +1,63 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..5"
 
 balance="round-robin"
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 gmirror remove $name ${us0}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 gmirror remove $name ${us1}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 gmirror remove $name ${us2}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 # mirror/${name} should be removed.
 if [ -c /dev/${name} ]; then
 	echo "not ok 5"
 else
 	echo "ok 5"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/4_test.sh b/tests/sys/geom/class/mirror/4_test.sh
index 46222fbecb2c..a5f469a2d95e 100644
--- a/tests/sys/geom/class/mirror/4_test.sh
+++ b/tests/sys/geom/class/mirror/4_test.sh
@@ -1,65 +1,65 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..5"
 
 balance="load"
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 gmirror remove $name ${us0}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 gmirror remove $name ${us1}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 gmirror remove $name ${us2}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 gmirror destroy $name
 
 # mirror/${name} should be removed.
 if [ -c /dev/${name} ]; then
 	echo "not ok 5"
 else
 	echo "ok 5"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/5_test.sh b/tests/sys/geom/class/mirror/5_test.sh
index 7bdb122255e4..43062dc1feea 100644
--- a/tests/sys/geom/class/mirror/5_test.sh
+++ b/tests/sys/geom/class/mirror/5_test.sh
@@ -1,63 +1,63 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..5"
 
 balance="split"
 ddbs=8192
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance -s `expr $ddbs / 2` $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 gmirror remove $name ${us0}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 gmirror remove $name ${us1}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 gmirror remove $name ${us2}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 # mirror/${name} should be removed.
 if [ -c /dev/${name} ]; then
 	echo "not ok 5"
 else
 	echo "ok 5"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/6_test.sh b/tests/sys/geom/class/mirror/6_test.sh
index 0baa511d0689..f37a45404642 100644
--- a/tests/sys/geom/class/mirror/6_test.sh
+++ b/tests/sys/geom/class/mirror/6_test.sh
@@ -1,44 +1,44 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..2"
 
 balance="split"
 ddbs=8192
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance -s `expr $ddbs / 2` $name /dev/${us0} /dev/${us1} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 dd if=/dev/zero of=/dev/${us2} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 # Connect disk to the mirror.
 gmirror insert ${name} ${us2}
 # Wait for synchronization.
 sleep 1
 dd if=/dev/${us2} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/7_test.sh b/tests/sys/geom/class/mirror/7_test.sh
index 2eded509a337..5f93f2fc4943 100644
--- a/tests/sys/geom/class/mirror/7_test.sh
+++ b/tests/sys/geom/class/mirror/7_test.sh
@@ -1,63 +1,63 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..5"
 
 balance="prefer"
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us1=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
-us2=$(attach_md -t malloc -s `expr $nblocks1 + 1`) || exit 1
+attach_md us0 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us1 -t malloc -s `expr $nblocks1 + 1` || exit 1
+attach_md us2 -t malloc -s `expr $nblocks1 + 1` || exit 1
 
 gmirror label -b $balance $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/mirror/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 gmirror remove $name ${us0}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 gmirror remove $name ${us1}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 gmirror remove $name ${us2}
 dd if=/dev/mirror/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 # mirror/${name} should be removed.
 if [ -c /dev/${name} ]; then
 	echo "not ok 5"
 else
 	echo "ok 5"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/mirror/8_test.sh b/tests/sys/geom/class/mirror/8_test.sh
index 5b3e5c3543a1..baea157a0ba8 100644
--- a/tests/sys/geom/class/mirror/8_test.sh
+++ b/tests/sys/geom/class/mirror/8_test.sh
@@ -1,55 +1,55 @@
 #!/bin/sh
 
 # Regression test for r317712.
 
 . `dirname $0`/conf.sh
 
 if ! [ -c /dev/mdctl ]; then
     echo "1..0 # SKIP no /dev/mdctl to create md devices"
     exit 0
 fi
 
 echo 1..1
 
 ddbs=2048
 m1=`mktemp $base.XXXXXX` || exit 1
 m2=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/zero of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 
 us0=$(mdconfig -t vnode -f $m1) || exit 1
 us1=$(mdconfig -t vnode -f $m2) || exit 1
 
 gmirror label $name /dev/$us0 /dev/$us1 || exit 1
 devwait
 
 # Ensure that the mirrors are marked dirty, and then disconnect them.
 # We need to have the gmirror provider open when destroying the MDs since
 # gmirror will automatically mark the mirrors clean when the provider is closed.
 exec 9>/dev/mirror/$name
 dd if=/dev/zero bs=$ddbs count=1 >&9 2>/dev/null
 mdconfig -d -u ${us0#md} -o force || exit 1
 mdconfig -d -u ${us1#md} -o force || exit 1
 exec 9>&-
 
 dd if=/dev/random of=$m1 bs=$ddbs count=1 conv=notrunc >/dev/null 2>&1
-us0=$(attach_md -t vnode -f $m1) || exit 1
+attach_md us0 -t vnode -f $m1 || exit 1
 devwait # This will take kern.geom.mirror.timeout seconds.
 
 # Re-attach the second mirror and wait for it to synchronize.
-us1=$(attach_md -t vnode -f $m2) || exit 1
+attach_md us1 -t vnode -f $m2 || exit 1
 syncwait
 
 # Verify the two mirrors are identical. Destroy the gmirror first so that
 # the mirror metadata is wiped; otherwise the metadata blocks will fail
 # the comparison. It would be nice to do this with a "gmirror verify"
 # command instead.
 gmirror destroy $name
 if cmp -s ${m1} ${m2}; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 rm -f $m1 $m2
diff --git a/tests/sys/geom/class/mirror/9_test.sh b/tests/sys/geom/class/mirror/9_test.sh
index a350ce9dfe3a..6bcb26860615 100644
--- a/tests/sys/geom/class/mirror/9_test.sh
+++ b/tests/sys/geom/class/mirror/9_test.sh
@@ -1,57 +1,57 @@
 #!/bin/sh
 
 # Regression test for r306743.
 
 . `dirname $0`/conf.sh
 
 echo 1..1
 
 ddbs=2048
 m1=`mktemp $base.XXXXXX` || exit 1
 m2=`mktemp $base.XXXXXX` || exit 1
 m3=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/zero of=$m1 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m2 bs=$ddbs count=1024 >/dev/null 2>&1
 dd if=/dev/zero of=$m3 bs=$ddbs count=1024 >/dev/null 2>&1
 
-us0=$(attach_md -t vnode -f $m1) || exit 1
-us1=$(attach_md -t vnode -f $m2) || exit 1
-us2=$(attach_md -t vnode -f $m3) || exit 1
+attach_md us0 -t vnode -f $m1 || exit 1
+attach_md us1 -t vnode -f $m2 || exit 1
+attach_md us2 -t vnode -f $m3 || exit 1
 
 gmirror label $name /dev/$us0 /dev/$us1 || exit 1
 devwait
 
 # Break one of the mirrors by forcing a single metadata write error.
 # When dd closes the mirror provider, gmirror will attempt to mark the mirrors
 # clean, and will kick one of the mirrors out upon hitting the error.
 sysctl debug.fail_point.g_mirror_metadata_write="1*return(5)[pid $(gmirror_worker_pid)]" || exit 1
 dd if=/dev/random of=/dev/mirror/$name bs=$ddbs count=1 >/dev/null 2>&1
 sysctl debug.fail_point.g_mirror_metadata_write='off' || exit 1
 
 # Replace the broken mirror, and then stop the gmirror.
 gmirror forget $name || exit 1
 gmirror insert $name /dev/$us2 || exit 1
 syncwait
 gmirror stop $name || exit 1
 
 # Restart the gmirror on the original two mirrors. One of them is broken,
 # so we should end up with a degraded gmirror.
 gmirror activate $name /dev/$us0 /dev/$us1 || exit 1
 devwait
 dd if=/dev/random of=/dev/mirror/$name bs=$ddbs count=1 >/dev/null 2>&1
 
 # Re-add the replacement mirror and verify the two mirrors are synchronized.
 # Destroy the gmirror first so that the mirror metadata is wiped; otherwise
 # the metadata blocks will fail the comparison. It would be nice to do this
 # with a "gmirror verify" command instead.
 gmirror activate $name /dev/$us2 || exit 1
 syncwait
 gmirror destroy $name || exit 1
 if cmp -s $m1 $m3; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 
 rm -f $m1 $m2 $m3
diff --git a/tests/sys/geom/class/mirror/component_selection.sh b/tests/sys/geom/class/mirror/component_selection.sh
index 7c7020eb6e6b..b5c8cec78c61 100755
--- a/tests/sys/geom/class/mirror/component_selection.sh
+++ b/tests/sys/geom/class/mirror/component_selection.sh
@@ -1,139 +1,139 @@
 
 ATF_TEST=true
 class=mirror
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case run_latest_genid cleanup
 run_latest_genid_head()
 {
 	atf_set "descr" \
 	    "Ensure that we properly select components (latest genid) during STARTING."
 	atf_set "require.user" "root"
 }
 run_latest_genid_body()
 {
 	geom_atf_test_setup
 	if ! error_message=$(geom_load_class_if_needed nop); then
 		atf_skip "$error_message"
 	fi
 
 	f1=$(mktemp ${base}.XXXXXX)
 	f2=$(mktemp ${base}.XXXXXX)
 	f3=$(mktemp ${base}.XXXXXX)
 	rnd1=$(mktemp ${base}.XXXXXX)
 	rnd2=$(mktemp ${base}.XXXXXX)
 
 	atf_check truncate -s 2M $f1
 	atf_check truncate -s 2M $f2
 	atf_check truncate -s 2M $f3
 	dd if=/dev/urandom bs=512 count=1 of="$rnd1"
 	dd if=/dev/urandom bs=512 count=1 of="$rnd2"
 
-	md1=$(attach_md -t vnode -f ${f1})
-	md2=$(attach_md -t vnode -f ${f2})
-	md3=$(attach_md -t vnode -f ${f3})
+	attach_md md1 -t vnode -f ${f1}
+	attach_md md2 -t vnode -f ${f2}
+	attach_md md3 -t vnode -f ${f3}
 
 	# Use a gnop for md1 just for consistency; it's not used for anything.
 	atf_check gnop create $md1
 	atf_check gnop create $md2
 	atf_check gnop create $md3
 	# Hardcode component names so that the non-.nop device isn't tasted
 	# instead.
 	atf_check gmirror label -h $name ${md1}.nop
 	devwait
 
 	atf_check gmirror insert -h $name ${md2}.nop
 	atf_check gmirror insert -h $name ${md3}.nop
 	syncwait
 
 	# Fail mirror 3, writing known contents to mirror 1+2 block 1
 	atf_check -s exit:0 -e empty -o empty \
 	    gnop configure -w 100 ${md3}.nop
 	atf_check -s exit:0 dd if="$rnd1" bs=512 count=1 oseek=1 conv=notrunc \
 	    of=/dev/mirror/$name status=none
 
 	disconnectwait nop "${md3}.nop"
 
 	# Should have two mirrors remaining after md3 was evicted
 	atf_check [ $(gmirror status -s $name | wc -l) -eq 2 ]
 	atf_check -s exit:0 -o match:"DEGRADED  ${md1}.nop \(ACTIVE\)" \
 		gmirror status -s $name
 	atf_check -s exit:0 -o match:"DEGRADED  ${md2}.nop \(ACTIVE\)" \
 		gmirror status -s $name
 
 	# Repeat:
 	# Fail mirror 2, writing known contents to mirror 1 block 2
 	atf_check -s exit:0 -e empty -o empty \
 	    gnop configure -w 100 ${md2}.nop
 	atf_check -s exit:0 dd if="$rnd2" bs=512 count=2 oseek=1 conv=notrunc \
 	    of=/dev/mirror/$name status=none
 
 	disconnectwait nop "${md2}.nop"
 
 	# Should have one mirror remaining after md2 was evicted
 	atf_check [ $(gmirror status -s $name | wc -l) -eq 1 ]
 	atf_check -s exit:0 -o match:"DEGRADED  ${md1}.nop \(ACTIVE\)" \
 		gmirror status -s $name
 
 	# Stop the mirror and remove the pieces so gmirror can't see them.
 	atf_check gmirror stop $name
 	atf_check gnop destroy ${md1}.nop
 	atf_check gnop destroy ${md2}.nop
 	atf_check gnop destroy ${md3}.nop
 
 	# Rebuild; spin up "disk" with lowest genid
 	atf_check gnop create $md3
 	md3gen=$(gmirror dump /dev/${md3}.nop | grep genid | cut -d: -f2)
 	# Assert gmirror is referencing this component for now:
 	atf_check [ $(consumerrefs nop ${md3}.nop) = "r1w1e1" ]
 
 	# Adding newer genid should kick out old component
 	atf_check gnop create $md2
 	md2gen=$(gmirror dump /dev/${md2}.nop | grep genid | cut -d: -f2)
 	atf_check [ $md2gen -gt $md3gen ]
 
 	disconnectwait nop "${md3}.nop"
 
 	# Can't test this because 'status' doesn't exist until RUNNING:
 	#atf_check [ $(gmirror status -s $name | wc -l) -eq 1 ]
 	# But as a substitute, assert gmirror has dropped reference to staler
 	# component in favor of newer component:
 	atf_check [ $(consumerrefs nop ${md2}.nop) = "r1w1e1" ]
 
 	# ditto
 	atf_check gnop create $md1
 	md1gen=$(gmirror dump /dev/${md1}.nop | grep genid | cut -d: -f2)
 	atf_check [ $md1gen -gt $md2gen ]
 
 	disconnectwait nop "${md2}.nop"
 
 	# Assert gmirror has dropped reference to stale component in favor of
 	# newer component:
 	atf_check [ $(consumerrefs nop ${md1}.nop) = "r1w1e1" ]
 
 	# gmirror won't start the mirror automatically with only one component
 	# ($md0) of configured three, so this waits out the
 	# kern.geom.mirror.timeout:
 	devwait
 
 	atf_check [ $(gmirror status -s $name | wc -l) -eq 1 ]
 	atf_check -s exit:0 -o match:"DEGRADED  ${md1}.nop \(ACTIVE\)" \
 		gmirror status -s $name
 }
 run_latest_genid_cleanup()
 {
 	. $(atf_get_srcdir)/conf.sh
 
 	if [ -f "$TEST_MDS_FILE" ]; then
 		while read test_md; do
 			echo "# Removing test gnop: ${test_md}.nop"
 			gnop destroy -f "${test_md}.nop" 2>/dev/null || :
 		done < "$TEST_MDS_FILE"
 	fi
 	gmirror_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case run_latest_genid
 }
diff --git a/tests/sys/geom/class/mirror/sync_error.sh b/tests/sys/geom/class/mirror/sync_error.sh
index 6b59dbe4fd4c..c51418151f0a 100644
--- a/tests/sys/geom/class/mirror/sync_error.sh
+++ b/tests/sys/geom/class/mirror/sync_error.sh
@@ -1,108 +1,108 @@
 
 ATF_TEST=true
 . $(atf_get_srcdir)/conf.sh
 
 REG_READ_FP=debug.fail_point.g_mirror_regular_request_read
 
 atf_test_case sync_read_error_2_disks cleanup
 sync_read_error_2_disks_head()
 {
 	atf_set "descr" \
 		"Ensure that we properly handle read errors during synchronization."
 	atf_set "require.user" "root"
 }
 sync_read_error_2_disks_body()
 {
 	geom_atf_test_setup
 
 	f1=$(mktemp ${base}.XXXXXX)
 	f2=$(mktemp ${base}.XXXXXX)
 
 	atf_check dd if=/dev/zero bs=1M count=32 of=$f1 status=none
 	atf_check truncate -s 32M $f2 
 
-	md1=$(attach_md -t vnode -f ${f1})
-	md2=$(attach_md -t vnode -f ${f2})
+	attach_md md1 -t vnode -f ${f1}
+	attach_md md2 -t vnode -f ${f2}
 
 	atf_check gmirror label $name $md1
 	devwait
 
 	atf_check -s ignore -e empty -o not-empty sysctl ${REG_READ_FP}="1*return(5)[pid $(gmirror_worker_pid)]"
 
 	# If a read error occurs while synchronizing and the mirror contains
 	# a single active disk, gmirror has no choice but to fail the
 	# synchronization and kick the new disk out of the mirror.
 	atf_check gmirror insert $name $md2
 	sleep 0.1
 	syncwait
 	atf_check [ $(gmirror status -s $name | wc -l) -eq 1 ]
 	atf_check -s exit:0 -o match:"DEGRADED  $md1 \(ACTIVE\)" \
 		gmirror status -s $name
 }
 sync_read_error_2_disks_cleanup()
 {
 	atf_check -s ignore -e ignore -o ignore sysctl ${REG_READ_FP}='off'
 	gmirror_test_cleanup
 }
 
 atf_test_case sync_read_error_3_disks cleanup
 sync_read_error_3_disks_head()
 {
 	atf_set "descr" \
 		"Ensure that we properly handle read errors during synchronization."
 	atf_set "require.user" "root"
 }
 sync_read_error_3_disks_body()
 {
 	geom_atf_test_setup
 
 	f1=$(mktemp ${base}.XXXXXX)
 	f2=$(mktemp ${base}.XXXXXX)
 	f3=$(mktemp ${base}.XXXXXX)
 
 	atf_check dd if=/dev/random bs=1M count=32 of=$f1 status=none
 	atf_check truncate -s 32M $f2
 	atf_check truncate -s 32M $f3
 
-	md1=$(attach_md -t vnode -f ${f1})
-	md2=$(attach_md -t vnode -f ${f2})
-	md3=$(attach_md -t vnode -f ${f3})
+	attach_md md1 -t vnode -f ${f1}
+	attach_md md2 -t vnode -f ${f2}
+	attach_md md3 -t vnode -f ${f3}
 
 	atf_check gmirror label $name $md1
 	devwait
 
 	atf_check gmirror insert $name $md2
 	syncwait
 
 	atf_check -s exit:0 -e empty -o not-empty sysctl ${REG_READ_FP}="1*return(5)[pid $(gmirror_worker_pid)]"
 
 	# If a read error occurs while synchronizing a new disk, and we have
 	# multiple active disks, we retry the read after an error. The disk
 	# which returned the read error is kicked out of the mirror.
 	atf_check gmirror insert $name $md3
 	syncwait
 	atf_check [ $(gmirror status -s $name | wc -l) -eq 2 ]
 	atf_check -s exit:0 -o match:"DEGRADED  $md3 \(ACTIVE\)" \
 		gmirror status -s $name
 
 	# Make sure that the two active disks are identical. Destroy the
 	# mirror first so that the metadata sectors are wiped.
 	if $(gmirror status -s $name | grep -q $md1); then
 		active=$md1
 	else
 		active=$md2
 	fi
 	atf_check gmirror destroy $name
 	atf_check cmp /dev/$active /dev/$md3
 }
 sync_read_error_3_disks_cleanup()
 {
 	atf_check -s ignore -e ignore -o ignore sysctl ${REG_READ_FP}='off'
 	gmirror_test_cleanup
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case sync_read_error_2_disks
 	atf_add_test_case sync_read_error_3_disks
 }
diff --git a/tests/sys/geom/class/raid3/10_test.sh b/tests/sys/geom/class/raid3/10_test.sh
index da141c5992ae..ec7c47253465 100644
--- a/tests/sys/geom/class/raid3/10_test.sh
+++ b/tests/sys/geom/class/raid3/10_test.sh
@@ -1,31 +1,31 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label -r $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/11_test.sh b/tests/sys/geom/class/raid3/11_test.sh
index 56a126a91cb4..73aa1cc7f982 100644
--- a/tests/sys/geom/class/raid3/11_test.sh
+++ b/tests/sys/geom/class/raid3/11_test.sh
@@ -1,31 +1,31 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label -w $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/12_test.sh b/tests/sys/geom/class/raid3/12_test.sh
index 5224521223a8..4284ac616ac1 100644
--- a/tests/sys/geom/class/raid3/12_test.sh
+++ b/tests/sys/geom/class/raid3/12_test.sh
@@ -1,37 +1,37 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 nblocks1=9
 nblocks2=`expr $nblocks1 - 1`
 nblocks3=`expr $nblocks2 / 2`
 
-us0=$(attach_md -t malloc -s $nblocks1) || exit 1
-us1=$(attach_md -t malloc -s $nblocks1) || exit 1
-us2=$(attach_md -t malloc -s $nblocks1) || exit 1
+attach_md us0 -t malloc -s $nblocks1 || exit 1
+attach_md us1 -t malloc -s $nblocks1 || exit 1
+attach_md us2 -t malloc -s $nblocks1 || exit 1
 
 dd if=/dev/random of=/dev/${us0} count=$nblocks1 >/dev/null 2>&1
 dd if=/dev/random of=/dev/${us1} count=$nblocks1 >/dev/null 2>&1
 dd if=/dev/random of=/dev/${us2} count=$nblocks1 >/dev/null 2>&1
 
 graid3 label -w $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 # Wait for synchronization.
 sleep 2
 graid3 stop $name
 # Break one component.
 dd if=/dev/random of=/dev/${us1} count=$nblocks2 >/dev/null 2>&1
 # Provoke retaste of the rest components.
 true > /dev/${us0}
 true > /dev/${us2}
 sleep 1
 
 dd if=/dev/raid3/${name} of=/dev/null bs=1k count=$nblocks3 >/dev/null 2>&1
 ec=$?
 if [ $ec -eq 0 ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
diff --git a/tests/sys/geom/class/raid3/1_test.sh b/tests/sys/geom/class/raid3/1_test.sh
index 638439c9ab9f..1df627114135 100644
--- a/tests/sys/geom/class/raid3/1_test.sh
+++ b/tests/sys/geom/class/raid3/1_test.sh
@@ -1,27 +1,27 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..2"
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} 2>/dev/null || exit 1
 devwait
 
 # Size of created device should be 2MB - 1024B.
 
 mediasize=`diskinfo /dev/raid3/${name} | awk '{print $3}'`
 if [ $mediasize -eq 2096128 ]; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 sectorsize=`diskinfo /dev/raid3/${name} | awk '{print $2}'`
 if [ $sectorsize -eq 1024 ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
diff --git a/tests/sys/geom/class/raid3/2_test.sh b/tests/sys/geom/class/raid3/2_test.sh
index f8642160c6fc..db16542f77ed 100644
--- a/tests/sys/geom/class/raid3/2_test.sh
+++ b/tests/sys/geom/class/raid3/2_test.sh
@@ -1,31 +1,31 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/3_test.sh b/tests/sys/geom/class/raid3/3_test.sh
index 656a9ad04328..64d7d5caaaf3 100644
--- a/tests/sys/geom/class/raid3/3_test.sh
+++ b/tests/sys/geom/class/raid3/3_test.sh
@@ -1,35 +1,35 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 #
 # Reading without one DATA component (so with parity).
 #
 graid3 remove -n 1 $name
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/4_test.sh b/tests/sys/geom/class/raid3/4_test.sh
index 698044f0c425..749729407368 100644
--- a/tests/sys/geom/class/raid3/4_test.sh
+++ b/tests/sys/geom/class/raid3/4_test.sh
@@ -1,35 +1,35 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 #
 # Writing without one DATA component.
 #
 graid3 remove -n 1 $name
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/5_test.sh b/tests/sys/geom/class/raid3/5_test.sh
index 66cfa9e58b8b..76d90cb60754 100644
--- a/tests/sys/geom/class/raid3/5_test.sh
+++ b/tests/sys/geom/class/raid3/5_test.sh
@@ -1,35 +1,35 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 #
 # Writing without PARITY component.
 #
 graid3 remove -n 2 $name
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/6_test.sh b/tests/sys/geom/class/raid3/6_test.sh
index 562c6f021e88..4c1d3288b82b 100644
--- a/tests/sys/geom/class/raid3/6_test.sh
+++ b/tests/sys/geom/class/raid3/6_test.sh
@@ -1,39 +1,39 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 #
 # Rebuild of DATA component.
 #
 graid3 remove -n 1 $name
 dd if=/dev/zero of=/dev/${us1} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 graid3 insert -n 1 $name md${us1}
 sleep 1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/7_test.sh b/tests/sys/geom/class/raid3/7_test.sh
index e2aeb783890f..53933c96cd99 100644
--- a/tests/sys/geom/class/raid3/7_test.sh
+++ b/tests/sys/geom/class/raid3/7_test.sh
@@ -1,42 +1,42 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 #
 # Rebuild of PARITY component.
 #
 graid3 remove -n 2 $name
 dd if=/dev/zero of=/dev/${us2} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 graid3 insert -n 2 $name md${us2}
 sleep 1
 # Remove DATA component, so PARITY component can be used while reading.
 graid3 remove -n 1 $name
 dd if=/dev/zero of=/dev/${us1} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/8_test.sh b/tests/sys/geom/class/raid3/8_test.sh
index bd3463a465f2..4c31ec0d4b1c 100644
--- a/tests/sys/geom/class/raid3/8_test.sh
+++ b/tests/sys/geom/class/raid3/8_test.sh
@@ -1,38 +1,38 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 #
 # Writing without DATA component and rebuild of DATA component.
 #
 graid3 remove -n 1 $name
 dd if=/dev/zero of=/dev/${us1} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 graid3 insert -n 1 $name md${us1}
 sleep 1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/raid3/9_test.sh b/tests/sys/geom/class/raid3/9_test.sh
index dc26ff53b6ce..880b2a20c817 100644
--- a/tests/sys/geom/class/raid3/9_test.sh
+++ b/tests/sys/geom/class/raid3/9_test.sh
@@ -1,41 +1,41 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 ddbs=2048
 nblocks1=1024
 nblocks2=`expr $nblocks1 / \( $ddbs / 512 \)`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
-us0=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us1=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
-us2=$(attach_md -t malloc -s $(expr $nblocks1 + 1)) || exit 1
+attach_md us0 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us1 -t malloc -s $(expr $nblocks1 + 1) || exit 1
+attach_md us2 -t malloc -s $(expr $nblocks1 + 1) || exit 1
 
 dd if=/dev/random of=${src} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 
 graid3 label $name /dev/${us0} /dev/${us1} /dev/${us2} || exit 1
 devwait
 
 #
 # Writing without PARITY component and rebuild of PARITY component.
 #
 graid3 remove -n 2 $name
 dd if=/dev/zero of=/dev/${us2} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 dd if=${src} of=/dev/raid3/${name} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 graid3 insert -n 2 $name md${us2}
 sleep 1
 # Remove DATA component, so PARITY component can be used while reading.
 graid3 remove -n 1 $name
 dd if=/dev/zero of=/dev/${us1} bs=512 count=`expr $nblocks1 + 1` >/dev/null 2>&1
 
 dd if=/dev/raid3/${name} of=${dst} bs=$ddbs count=$nblocks2 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/shsec/1_test.sh b/tests/sys/geom/class/shsec/1_test.sh
index f1e6ab4137a1..93e1c02e7cf9 100644
--- a/tests/sys/geom/class/shsec/1_test.sh
+++ b/tests/sys/geom/class/shsec/1_test.sh
@@ -1,27 +1,27 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..2"
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 gshsec label $name /dev/${us0} /dev/${us1} /dev/${us2} 2>/dev/null || exit 1
 devwait
 
 # Size of created device should be 1MB - 512B.
 
 mediasize=`diskinfo /dev/shsec/${name} | awk '{print $3}'`
 if [ $mediasize -eq 1048064 ]; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
 sectorsize=`diskinfo /dev/shsec/${name} | awk '{print $2}'`
 if [ $sectorsize -eq 512 ]; then
 	echo "ok 2"
 else
 	echo "not ok 2"
 fi
diff --git a/tests/sys/geom/class/shsec/2_test.sh b/tests/sys/geom/class/shsec/2_test.sh
index b16084218eed..4f4ab3404ee0 100644
--- a/tests/sys/geom/class/shsec/2_test.sh
+++ b/tests/sys/geom/class/shsec/2_test.sh
@@ -1,51 +1,51 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..4"
 
 nblocks1=1024
 nblocks2=`expr $nblocks1 + 1`
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} count=$nblocks1 >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s $nblocks2) || exit 1
-us1=$(attach_md -t malloc -s $nblocks2) || exit 1
-us2=$(attach_md -t malloc -s $nblocks2) || exit 1
+attach_md us0 -t malloc -s $nblocks2 || exit 1
+attach_md us1 -t malloc -s $nblocks2 || exit 1
+attach_md us2 -t malloc -s $nblocks2 || exit 1
 
 gshsec label $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 dd if=${src} of=/dev/shsec/${name} count=$nblocks1 >/dev/null 2>&1
 
 dd if=/dev/shsec/${name} of=${dst} count=$nblocks1 >/dev/null 2>&1
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 dd if=/dev/${us0} of=${dst} count=$nblocks1 >/dev/null 2>&1
 if [ `md5 -q ${src}` = `md5 -q ${dst}` ]; then
 	echo "not ok 2"
 else
 	echo "ok 2"
 fi
 
 dd if=/dev/${us1} of=${dst} count=$nblocks1 >/dev/null 2>&1
 if [ `md5 -q ${src}` = `md5 -q ${dst}` ]; then
 	echo "not ok 3"
 else
 	echo "ok 3"
 fi
 
 dd if=/dev/${us2} of=${dst} count=$nblocks1 >/dev/null 2>&1
 if [ `md5 -q ${src}` = `md5 -q ${dst}` ]; then
 	echo "not ok 4"
 else
 	echo "ok 4"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/stripe/1_test.sh b/tests/sys/geom/class/stripe/1_test.sh
index 9878baa30e86..a717866a0c5c 100644
--- a/tests/sys/geom/class/stripe/1_test.sh
+++ b/tests/sys/geom/class/stripe/1_test.sh
@@ -1,22 +1,22 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 gstripe create -s 16384 $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 # Size of created device should be 1MB * 3.
 
 size=`diskinfo /dev/stripe/${name} | awk '{print $3}'`
 
 if [ $size -eq 3145728 ]; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
diff --git a/tests/sys/geom/class/stripe/2_test.sh b/tests/sys/geom/class/stripe/2_test.sh
index 3558cf99146b..c4b1f2344629 100644
--- a/tests/sys/geom/class/stripe/2_test.sh
+++ b/tests/sys/geom/class/stripe/2_test.sh
@@ -1,29 +1,29 @@
 #!/bin/sh
 
 . `dirname $0`/conf.sh
 
 echo "1..1"
 
 tsize=3
 src=`mktemp $base.XXXXXX` || exit 1
 dst=`mktemp $base.XXXXXX` || exit 1
 
 dd if=/dev/random of=${src} bs=1m count=$tsize >/dev/null 2>&1
 
-us0=$(attach_md -t malloc -s 1M) || exit 1
-us1=$(attach_md -t malloc -s 2M) || exit 1
-us2=$(attach_md -t malloc -s 3M) || exit 1
+attach_md us0 -t malloc -s 1M || exit 1
+attach_md us1 -t malloc -s 2M || exit 1
+attach_md us2 -t malloc -s 3M || exit 1
 
 gstripe create -s 8192 $name /dev/$us0 /dev/$us1 /dev/$us2 || exit 1
 devwait
 
 dd if=${src} of=/dev/stripe/${name} bs=1m count=$tsize >/dev/null 2>&1
 dd if=/dev/stripe/${name} of=${dst} bs=1m count=$tsize >/dev/null 2>&1
 
 if [ `md5 -q ${src}` != `md5 -q ${dst}` ]; then
 	echo "not ok 1"
 else
 	echo "ok 1"
 fi
 
 rm -f ${src} ${dst}
diff --git a/tests/sys/geom/class/union/union_test.sh b/tests/sys/geom/class/union/union_test.sh
index 1872847bdf58..9d02cae83e8a 100644
--- a/tests/sys/geom/class/union/union_test.sh
+++ b/tests/sys/geom/class/union/union_test.sh
@@ -1,338 +1,338 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2023 The FreeBSD Foundation
 #
 # This software was developed1 by Yan-Hao Wang <bses30074@gmail.com>
 # under sponsorship from the FreeBSD Foundation.
 #
 # 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.
 #
 
 . $(atf_get_srcdir)/conf.sh
 
 atf_test_case create cleanup
 create_head()
 {
     atf_set "descr" "Test gunion create and destroy"
     atf_set "require.user" "root"
 }
 create_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
 
     atf_check gunion create "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     atf_check -o inline:"/dev/${guniondev}\n" ls "/dev/${guniondev}"
     atf_check -o ignore fsck -p -f "/dev/${guniondev}"
 
     atf_check gunion destroy "$guniondev"
     atf_check -s not-exit:0 -o ignore -e ignore ls "/dev/${guniondev}"
 }
 create_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case basic cleanup
 basic_head()
 {
     atf_set "descr" "Check gunion doesn't affect lowerdev status and lowerdev can't be mounted when being in a gunion"
     atf_set "require.user" "root"
 }
 basic_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
     mkdir lowermnt
     mkdir gunionmnt
 
     mount "/dev/${lowerdev}" lowermnt
     echo "lower file" > lower_file
     cp lower_file lowermnt/lower_file
     sync
     umount lowermnt
 
     gunion create "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     atf_check -s not-exit:0 -o ignore -e ignore mount "/dev/${lowerdev}" lowermnt
 
     mount "/dev/${guniondev}" gunionmnt
     echo "update lower file" >> gunionmnt/lower_file
     echo "gunion file" > gunion_file
     cp gunion_file gunionmnt/gunion_file
     sync
     umount gunionmnt
 
     gunion destroy "$guniondev"
     mount "/dev/${lowerdev}" lowermnt
     checksum lowermnt/lower_file lower_file
     atf_check -s not-exit:0  -o ignore -e ignore ls lowermnt/gunion_file
 }
 basic_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case commit cleanup
 commit_head()
 {
     atf_set "descr" "Test basic gunion commit without option"
     atf_set "require.user" "root"
 }
 commit_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
     mkdir lowermnt
     mkdir gunionmnt
 
     mount "/dev/${lowerdev}" lowermnt
     echo "lower file" > lower_file
     cp lower_file lowermnt/lower_file
     sync
     umount lowermnt
 
     gunion create "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     mount "/dev/${guniondev}" gunionmnt
     checksum gunionmnt/lower_file lower_file
 
     echo "update lower file" >> lower_file
     cp -f lower_file gunionmnt/lower_file
     echo "gunion file" > gunion_file
     cp gunion_file gunionmnt/gunion_file
     sync
     umount gunionmnt
     atf_check gunion commit "$guniondev"
     gunion destroy "$guniondev"
 
     atf_check -o ignore fsck -p -f "/dev/${lowerdev}"
     mount "/dev/${lowerdev}" lowermnt
     checksum lowermnt/lower_file lower_file
     checksum lowermnt/gunion_file gunion_file
 }
 commit_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case offset cleanup
 offset_head()
 {
     atf_set "descr" "Test gunion create with -o offset option"
     atf_set "require.user" "root"
 }
 offset_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     gpart create -s GPT "/dev/${lowerdev}"
     gpart add -t freebsd-ufs "$lowerdev"
     newfs "/dev/${lowerdev}p1"
     gpt_entry_1=$(gpart show "/dev/${lowerdev}")
     mkdir gunionmnt
 
     secsize="$(diskinfo "/dev/${lowerdev}" | awk '{print $2}')"
     p1_start_sector="$(gpart show -p "/dev/${lowerdev}" | grep ${lowerdev}p1 | awk '{print $1}')"
     offset_size="$((secsize * p1_start_sector))"
 
     gunion create -o "$offset_size" "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
 
     atf_check -o ignore fsck -p -f "/dev/${guniondev}"
     atf_check mount "/dev/${guniondev}" gunionmnt
     umount gunionmnt
     gunion destroy "$guniondev"
 
     gpt_entry_2=$(gpart show "/dev/${lowerdev}")
     atf_check_equal "$gpt_entry_1" "$gpt_entry_2"
 }
 offset_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case size cleanup
 size_head()
 {
     atf_set "descr" "Test gunion create with -s size option"
     atf_set "require.user" "root"
 }
 size_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 2m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 2m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
 
     gunion create -s 2m "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     echo "$guniondev" > guniondev
 
     size="$(diskinfo "/dev/$guniondev" | awk '{print $3}')"
     atf_check_equal "2097152" "$size" # 2 MB = 2097152 bytes
 }
 size_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case secsize cleanup
 secsize_head()
 {
     atf_set "descr" "Test gunion create with -S secsize option"
     atf_set "require.user" "root"
 }
 secsize_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -S 512 -U "/dev/${lowerdev}"
     lower_secsize="$(diskinfo "/dev/${lowerdev}" | awk '{print $2}')"
     atf_check_equal "512" "$lower_secsize"
 
     gunion create -S 1024 "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     echo "$guniondev" > guniondev
 
     secsize="$(diskinfo "/dev/${guniondev}" | awk '{print $2}')"
     atf_check_equal "1024" "$secsize"
 }
 secsize_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case gunionname cleanup
 gunionname_head()
 {
     atf_set "descr" "Test gunion create with -Z gunionname option"
     atf_set "require.user" "root"
 }
 gunionname_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
 
     gunion create -Z gunion1 "$upperdev" "$lowerdev"
     echo "gunion1.union" > guniondev
     atf_check -o inline:"/dev/gunion1.union\n" ls /dev/gunion1.union
 }
 gunionname_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_test_case revert cleanup
 revert_head()
 {
     atf_set "descr" "Test gunion revert"
     atf_set "require.user" "root"
 }
 revert_body()
 {
     gunion_test_setup
 
-    upperdev="$(attach_md -s 1m)"
-    lowerdev="$(attach_md -s 1m)"
+    attach_md upperdev -s 1m
+    attach_md lowerdev -s 1m
     newfs -U "/dev/${lowerdev}"
     mkdir lowermnt
     mkdir gunionmnt
 
     mount "/dev/${lowerdev}" lowermnt
     echo "lower file" > lower_file
     cp lower_file lowermnt/lower_file
     sync
     umount lowermnt
 
     atf_check gunion create "$upperdev" "$lowerdev"
     guniondev="${upperdev}-${lowerdev}.union"
     mount "/dev/${guniondev}" gunionmnt
 
     echo "update lower file" >> gunionmnt/lower_file
     echo "gunion file" > gunion_file
     cp gunion_file gunionmnt/gunion_file
     sync
     umount gunionmnt
     atf_check gunion revert "$guniondev"
 
     mount "/dev/${guniondev}" gunionmnt
     checksum gunionmnt/lower_file lower_file
     atf_check -s not-exit:0 -o ignore -e ignore ls gunionmnt/gunion_file
 
     umount gunionmnt
     gunion destroy "$guniondev"
 }
 revert_cleanup()
 {
     gunion_test_cleanup
 }
 
 atf_init_test_cases()
 {
     atf_add_test_case create
     atf_add_test_case basic
     atf_add_test_case commit
     atf_add_test_case offset
     atf_add_test_case size
     atf_add_test_case secsize
     atf_add_test_case gunionname
     atf_add_test_case revert
 }
 
 checksum()
 {
     src=$1
     work=$2
 
     if [ ! -e "$src" ]; then
         atf_fail "file not exist"
     fi
     if [ ! -e "$work" ]; then
         atf_fail "file not exist"
     fi
 
     src_checksum=$(md5 -q "$src")
     work_checksum=$(md5 -q "$work")
 
     if [ "$work_checksum" != "$src_checksum" ]; then
         atf_fail "md5 checksum didn't match with ${src} and ${work}"
     fi
 }
diff --git a/tests/sys/geom/class/uzip/1_test.sh b/tests/sys/geom/class/uzip/1_test.sh
index 40c9fb44809d..066cacc158b4 100644
--- a/tests/sys/geom/class/uzip/1_test.sh
+++ b/tests/sys/geom/class/uzip/1_test.sh
@@ -1,33 +1,33 @@
 #!/bin/sh
 
 testsdir=$(dirname $0)
 . $testsdir/conf.sh
 
 # Check host endianness
 ret=$(echo I | tr -d "[:space:]" | od -to2 | head -n1 | awk '{print $2}' | cut -c6)
 if [ "$ret" = "1" ]; then
 	# Little endian
 	UUE=$testsdir/1_endian_little.img.uzip.uue
 elif [ "$ret" = "0" ]; then
 	# Big endian
 	UUE=$testsdir/1_endian_big.img.uzip.uue
 else
 	echo "Couldn't detect host endianness"
 	exit 2
 fi
 
 echo "1..1"
 
 uudecode $UUE
-us0=$(attach_md -f $(basename $UUE .uue)) || exit 1
+attach_md us0 -f $(basename $UUE .uue) || exit 1
 sleep 1
 
 mount -o ro /dev/${us0}.uzip "${mntpoint}" || exit 1
 
 #cat "${mntpoint}/etalon.txt"
 diff -I '\$FreeBSD.*\$' -u $testsdir/etalon/etalon.txt "${mntpoint}/etalon.txt"
 if [ $? -eq 0 ]; then
 	echo "ok 1"
 else
 	echo "not ok 1"
 fi
diff --git a/tests/sys/kern/sendfile_test.sh b/tests/sys/kern/sendfile_test.sh
index 2e9779d6779c..03d87292f3a3 100755
--- a/tests/sys/kern/sendfile_test.sh
+++ b/tests/sys/kern/sendfile_test.sh
@@ -1,168 +1,168 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2020 Netflix, Inc.
 #
 # 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.
 #
 
 #
 # These tests exercise a few basic cases for the sendfile() syscall:
 # - successful operation.
 # - sendfile() starts an async disk read but that async I/O fails.
 # - sendfile() fails to read an indirect block and thus cannot
 #   even start an async I/O.
 #
 # In all cases we request some read ahead in addition to
 # the data to be sent to the socket.
 #
 
 MD_DEVS="md.devs"
 MNT=mnt
 FILE=$MNT/file
 HELPER="$(atf_get_srcdir)/sendfile_helper"
 BSIZE=4096
 
 atf_test_case io_success cleanup
 io_success_head()
 {
 	atf_set "descr" "sendfile where all disk I/O succeeds"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_success_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
-	md=$(alloc_md)
+	alloc_md md
 	common_body_setup $md
 
 	atf_check $HELPER $FILE 0 0x10000 0x10000
 }
 io_success_cleanup()
 {
 	common_cleanup
 }
 
 atf_test_case io_fail_sync cleanup
 io_fail_sync_head()
 {
 	atf_set "descr" "sendfile where we fail to start async I/O"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_fail_sync_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
-	md=$(alloc_md)
+	alloc_md md
 	common_body_setup $md
 
 	atf_check gnop configure -r 100 -e 5 ${md}.nop
 	atf_check -s exit:3 -e ignore $HELPER $FILE $((12 * $BSIZE)) $BSIZE 0x10000
 }
 io_fail_sync_cleanup()
 {
 	common_cleanup
 }
 
 atf_test_case io_fail_async cleanup
 io_fail_async_head()
 {
 	atf_set "descr" "sendfile where an async I/O fails"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_fail_async_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
-	md=$(alloc_md)
+	alloc_md md
 	common_body_setup $md
 
 	atf_check gnop configure -r 100 -e 5 ${md}.nop
 	atf_check -s exit:2 -e ignore $HELPER $FILE 0 $BSIZE 0x10000
 }
 io_fail_async_cleanup()
 {
 	common_cleanup
 }
 
 
 atf_init_test_cases()
 {
 	atf_add_test_case io_success
 	atf_add_test_case io_fail_sync
 	atf_add_test_case io_fail_async
 }
 
 alloc_md()
 {
-	local md
+	local _md
 
 	[ -c /dev/mdctl ] || atf_skip "no /dev/mdctl to create md devices"
-	md=$(mdconfig -a -t swap -s 256M) || atf_fail "mdconfig -a failed"
-	echo ${md} >> $MD_DEVS
-	echo ${md}
+	_md=$(mdconfig -a -t swap -s 256M) || atf_fail "mdconfig -a failed"
+	echo ${_md} >> $MD_DEVS
+	eval "${1}='${_md}'"
 }
 
 common_body_setup()
 {
 	us=$1
 
 	atf_check mkdir $MNT
 	atf_check -o ignore -e ignore newfs -b $BSIZE -U -j /dev/${us}
 	atf_check mount /dev/${us} $MNT
 	atf_check -e ignore dd if=/dev/zero of=$FILE bs=1m count=1
 	atf_check umount $MNT
 
 	load_gnop
 	atf_check gnop create /dev/${us}
 	atf_check mount /dev/${us}.nop $MNT
 	atf_check -o ignore ls -l $MNT/file
 }
 
 common_cleanup()
 {
 	umount -f $MNT
 	if [ -f "$MD_DEVS" ]; then
 		while read test_md; do
 			gnop destroy -f ${test_md}.nop 2>/dev/null
 			mdconfig -d -u $test_md 2>/dev/null
 		done < $MD_DEVS
 		rm $MD_DEVS
 	fi
 
 	true
 }
 
 load_gnop()
 {
 	if ! kldstat -q -m g_nop; then
 		geom nop load || atf_skip "could not load module for geom nop"
 	fi
 }