diff --git a/tests/zfs-tests/tests/functional/alloc_class/alloc_class_013_pos.ksh b/tests/zfs-tests/tests/functional/alloc_class/alloc_class_013_pos.ksh
index 2ce22a6242..790a47f265 100755
--- a/tests/zfs-tests/tests/functional/alloc_class/alloc_class_013_pos.ksh
+++ b/tests/zfs-tests/tests/functional/alloc_class/alloc_class_013_pos.ksh
@@ -42,7 +42,8 @@ log_must display_status "$TESTPOOL"
 
 log_must zfs create -o dedup=on -V 2G $TESTPOOL/$TESTVOL
 
-log_must eval "new_fs $ZVOL_DEVDIR/$TESTPOOL/$TESTVOL >/dev/null 2>&1"
+block_device_wait "$ZVOL_DEVDIR/$TESTPOOL/$TESTVOL"
+log_must eval "new_fs $ZVOL_DEVDIR/$TESTPOOL/$TESTVOL >/dev/null"
 
 sync_pool
 log_must zpool list -v $TESTPOOL
diff --git a/tests/zfs-tests/tests/functional/cli_root/zpool_trim/zpool_trim_start_and_cancel_pos.ksh b/tests/zfs-tests/tests/functional/cli_root/zpool_trim/zpool_trim_start_and_cancel_pos.ksh
index fbb0c29104..19781137d3 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zpool_trim/zpool_trim_start_and_cancel_pos.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zpool_trim/zpool_trim_start_and_cancel_pos.ksh
@@ -35,7 +35,7 @@
 DISK1=${DISKS%% *}
 
 log_must zpool create -f $TESTPOOL $DISK1
-log_must zpool trim $TESTPOOL
+log_must zpool trim -r 1 $TESTPOOL
 
 [[ -z "$(trim_progress $TESTPOOL $DISK1)" ]] && \
     log_fail "TRIM did not start"