diff --git a/man/man4/zfs.4 b/man/man4/zfs.4
index 01baebb7d5..2c4cf80260 100644
--- a/man/man4/zfs.4
+++ b/man/man4/zfs.4
@@ -346,7 +346,10 @@ and the allocation can't actually be satisfied
 When a vdev is added, target this number of metaslabs per top-level vdev.
 .
 .It Sy zfs_vdev_default_ms_shift Ns = Ns Sy 29 Po 512MB Pc Pq int
-Default limit for metaslab size.
+Default lower limit for metaslab size.
+.
+.It Sy zfs_vdev_max_ms_shift Ns = Ns Sy 34 Po 16 GiB Pc Pq int
+Default upper limit for metaslab size.
 .
 .It Sy zfs_vdev_max_auto_ashift Ns = Ns Sy ASHIFT_MAX Po 16 Pc Pq ulong
 Maximum ashift used when optimizing for logical -> physical sector size on new
diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c
index 25d3f3ea6d..dc4f4ca8f0 100644
--- a/module/zfs/vdev.c
+++ b/module/zfs/vdev.c
@@ -5460,7 +5460,10 @@ ZFS_MODULE_PARAM(zfs_vdev, zfs_vdev_, default_ms_count, INT, ZMOD_RW,
 	"Target number of metaslabs per top-level vdev");
 
 ZFS_MODULE_PARAM(zfs_vdev, zfs_vdev_, default_ms_shift, INT, ZMOD_RW,
-	"Default limit for metaslab size");
+	"Default lower limit for metaslab size");
+
+ZFS_MODULE_PARAM(zfs_vdev, zfs_vdev_, max_ms_shift, INT, ZMOD_RW,
+	"Default upper limit for metaslab size");
 
 ZFS_MODULE_PARAM(zfs_vdev, zfs_vdev_, min_ms_count, INT, ZMOD_RW,
 	"Minimum number of metaslabs per top-level vdev");