Index: head/sys/dev/xen/balloon/balloon.c
===================================================================
--- head/sys/dev/xen/balloon/balloon.c
+++ head/sys/dev/xen/balloon/balloon.c
@@ -79,7 +79,9 @@
 #define bs balloon_stats
 
 SYSCTL_DECL(_dev_xen);
-static SYSCTL_NODE(_dev_xen, OID_AUTO, balloon, CTLFLAG_RD, NULL, "Balloon");
+static SYSCTL_NODE(_dev_xen, OID_AUTO, balloon,
+    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
+    "Balloon");
 SYSCTL_ULONG(_dev_xen_balloon, OID_AUTO, current, CTLFLAG_RD,
     &bs.current_pages, 0, "Current allocation");
 SYSCTL_ULONG(_dev_xen_balloon, OID_AUTO, target, CTLFLAG_RD,
Index: head/sys/dev/xen/blkfront/blkfront.c
===================================================================
--- head/sys/dev/xen/blkfront/blkfront.c
+++ head/sys/dev/xen/blkfront/blkfront.c
@@ -83,7 +83,8 @@
 static MALLOC_DEFINE(M_XENBLOCKFRONT, "xbd", "Xen Block Front driver data");
 
 static int xbd_enable_indirect = 1;
-SYSCTL_NODE(_hw, OID_AUTO, xbd, CTLFLAG_RD, 0, "xbd driver parameters");
+SYSCTL_NODE(_hw, OID_AUTO, xbd, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
+    "xbd driver parameters");
 SYSCTL_INT(_hw_xbd, OID_AUTO, xbd_enable_indirect, CTLFLAG_RDTUN,
     &xbd_enable_indirect, 0, "Enable xbd indirect segments");
 
@@ -926,8 +927,8 @@
 	    "communication channel pages (negotiated)");
 
 	SYSCTL_ADD_PROC(sysctl_ctx, children, OID_AUTO,
-	    "features", CTLTYPE_STRING|CTLFLAG_RD, xbd, 0,
-	    xbd_sysctl_features, "A", "protocol features (negotiated)");
+	    "features", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, xbd,
+	    0, xbd_sysctl_features, "A", "protocol features (negotiated)");
 }
 
 /*
Index: head/sys/dev/xen/netback/netback.c
===================================================================
--- head/sys/dev/xen/netback/netback.c
+++ head/sys/dev/xen/netback/netback.c
@@ -1157,7 +1157,7 @@
 			SYSCTL_CHILDREN(sysctl_tree),
 			OID_AUTO,
 			"unit_test_results",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
 			xnb,
 			0,
 			xnb_unit_test_main,
@@ -1168,7 +1168,7 @@
 			SYSCTL_CHILDREN(sysctl_tree),
 			OID_AUTO,
 			"dump_rings",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
 			xnb,
 			0,
 			xnb_dump_rings,
Index: head/sys/dev/xen/xenstore/xenstore.c
===================================================================
--- head/sys/dev/xen/xenstore/xenstore.c
+++ head/sys/dev/xen/xenstore/xenstore.c
@@ -1241,7 +1241,8 @@
 
 /*------------------------------- Sysctl Data --------------------------------*/
 /* XXX Shouldn't the node be somewhere else? */
-SYSCTL_NODE(_dev, OID_AUTO, xen, CTLFLAG_RD, NULL, "Xen");
+SYSCTL_NODE(_dev, OID_AUTO, xen, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
+    "Xen");
 SYSCTL_INT(_dev_xen, OID_AUTO, xsd_port, CTLFLAG_RD, &xs.evtchn, 0, "");
 SYSCTL_ULONG(_dev_xen, OID_AUTO, xsd_kva, CTLFLAG_RD, (u_long *) &xen_store, 0, "");
 
Index: head/sys/xen/xenbus/xenbusb.c
===================================================================
--- head/sys/xen/xenbus/xenbusb.c
+++ head/sys/xen/xenbus/xenbusb.c
@@ -351,7 +351,7 @@
 			SYSCTL_CHILDREN(tree),
 			OID_AUTO,
 			"xenstore_path",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 			dev,
 			XENBUS_IVAR_NODE,
 			xenbusb_device_sysctl_handler,
@@ -362,7 +362,7 @@
 			SYSCTL_CHILDREN(tree),
 			OID_AUTO,
 			"xenbus_dev_type",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 			dev,
 			XENBUS_IVAR_TYPE,
 			xenbusb_device_sysctl_handler,
@@ -373,7 +373,7 @@
 			SYSCTL_CHILDREN(tree),
 			OID_AUTO,
 			"xenbus_connection_state",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 			dev,
 			XENBUS_IVAR_STATE,
 			xenbusb_device_sysctl_handler,
@@ -384,7 +384,7 @@
 			SYSCTL_CHILDREN(tree),
 			OID_AUTO,
 			"xenbus_peer_domid",
-			CTLTYPE_INT | CTLFLAG_RD,
+			CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
 			dev,
 			XENBUS_IVAR_OTHEREND_ID,
 			xenbusb_device_sysctl_handler,
@@ -395,7 +395,7 @@
 			SYSCTL_CHILDREN(tree),
 			OID_AUTO,
 			"xenstore_peer_path",
-			CTLTYPE_STRING | CTLFLAG_RD,
+			CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 			dev,
 			XENBUS_IVAR_OTHEREND_PATH,
 			xenbusb_device_sysctl_handler,