diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt
index 4ed229789852..151584a1f950 100644
--- a/Documentation/ABI/testing/sysfs-bus-thunderbolt
+++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt
@@ -35,6 +35,9 @@ Description:	This attribute holds current Thunderbolt security level
 			minimum. User needs to authorize each device.
 		dponly: Automatically tunnel Display port (and USB). No
 			PCIe tunnels are created.
+		usbonly: Automatically tunnel USB controller of the
+			 connected Thunderbolt dock (and Display Port). All
+			 PCIe links downstream of the dock are removed.
 
 What: /sys/bus/thunderbolt/devices/.../authorized
 Date:		Sep 2017
diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst
index 9948ec36a204..35fccba6a9a6 100644
--- a/Documentation/admin-guide/thunderbolt.rst
+++ b/Documentation/admin-guide/thunderbolt.rst
@@ -21,11 +21,11 @@ vulnerable to DMA attacks.
 Security levels and how to use them
 -----------------------------------
 Starting with Intel Falcon Ridge Thunderbolt controller there are 4
-security levels available. The reason for these is the fact that the
-connected devices can be DMA masters and thus read contents of the host
-memory without CPU and OS knowing about it. There are ways to prevent
-this by setting up an IOMMU but it is not always available for various
-reasons.
+security levels available. Intel Titan Ridge added one more security level
+(usbonly). The reason for these is the fact that the connected devices can
+be DMA masters and thus read contents of the host memory without CPU and OS
+knowing about it. There are ways to prevent this by setting up an IOMMU but
+it is not always available for various reasons.
 
 The security levels are as follows:
 
@@ -52,6 +52,11 @@ The security levels are as follows:
     USB. No PCIe tunneling is done. In BIOS settings this is
     typically called *Display Port Only*.
 
+  usbonly
+    The firmware automatically creates tunnels for the USB controller and
+    Display Port in a dock. All PCIe links downstream of the dock are
+    removed.
+
 The current security level can be read from
 ``/sys/bus/thunderbolt/devices/domainX/security`` where ``domainX`` is
 the Thunderbolt domain the host controller manages. There is typically
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
index ab4b304306f7..6281266b8ec0 100644
--- a/drivers/thunderbolt/domain.c
+++ b/drivers/thunderbolt/domain.c
@@ -117,6 +117,7 @@ static const char * const tb_security_names[] = {
 	[TB_SECURITY_USER] = "user",
 	[TB_SECURITY_SECURE] = "secure",
 	[TB_SECURITY_DPONLY] = "dponly",
+	[TB_SECURITY_USBONLY] = "usbonly",
 };
 
 static ssize_t boot_acl_show(struct device *dev, struct device_attribute *attr,
@@ -227,8 +228,12 @@ static ssize_t security_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
 {
 	struct tb *tb = container_of(dev, struct tb, dev);
+	const char *name = "unknown";
 
-	return sprintf(buf, "%s\n", tb_security_names[tb->security_level]);
+	if (tb->security_level < ARRAY_SIZE(tb_security_names))
+		name = tb_security_names[tb->security_level];
+
+	return sprintf(buf, "%s\n", name);
 }
 static DEVICE_ATTR_RO(security);
 
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 47251844d064..a3ed26082bc1 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -45,12 +45,16 @@ enum tb_cfg_pkg_type {
  * @TB_SECURITY_USER: User approval required at minimum
  * @TB_SECURITY_SECURE: One time saved key required at minimum
  * @TB_SECURITY_DPONLY: Only tunnel Display port (and USB)
+ * @TB_SECURITY_USBONLY: Only tunnel USB controller of the connected
+ *			 Thunderbolt dock (and Display Port). All PCIe
+ *			 links downstream of the dock are removed.
  */
 enum tb_security_level {
 	TB_SECURITY_NONE,
 	TB_SECURITY_USER,
 	TB_SECURITY_SECURE,
 	TB_SECURITY_DPONLY,
+	TB_SECURITY_USBONLY,
 };
 
 /**