diff --git a/tests/zfs-tests/tests/functional/cli_root/zfs_upgrade/setup.ksh b/tests/zfs-tests/tests/functional/cli_root/zfs_upgrade/setup.ksh
index 4c1348a192..c9f36017df 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zfs_upgrade/setup.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zfs_upgrade/setup.ksh
@@ -39,4 +39,4 @@ else
    log_note "This machine is running ZFS Filesystem version $ZFS_VERSION"
 fi
 
-default_setup $DISKS
+default_setup "$DISKS"
diff --git a/tests/zfs-tests/tests/functional/write_dirs/setup.ksh b/tests/zfs-tests/tests/functional/write_dirs/setup.ksh
index 3aafdbdb38..9e70fc47b8 100755
--- a/tests/zfs-tests/tests/functional/write_dirs/setup.ksh
+++ b/tests/zfs-tests/tests/functional/write_dirs/setup.ksh
@@ -33,4 +33,4 @@
 
 verify_runnable "global"
 
-default_setup $DISKS
+default_setup "$DISKS"