Index: sys/dev/usb/usb_subr.c
===================================================================
RCS file: /cvsroot/src/sys/dev/usb/usb_subr.c,v
retrieving revision 1.198.2.26
diff -u -p -r1.198.2.26 usb_subr.c
--- sys/dev/usb/usb_subr.c	19 Mar 2016 07:12:21 -0000	1.198.2.26
+++ sys/dev/usb/usb_subr.c	12 Apr 2016 06:41:57 -0000
@@ -899,8 +899,10 @@ usbd_attachwholedevice(device_t parent, 
 	dlocs[USBDEVIFCF_CONFIGURATION] = -1;
 	dlocs[USBDEVIFCF_INTERFACE] = -1;
 
+	KERNEL_LOCK(1, NULL);
 	dv = config_found_sm_loc(parent, "usbdevif", dlocs, &uaa, usbd_print,
 				 config_stdsubmatch);
+	KERNEL_UNLOCK_ONE(NULL);
 	if (dv) {
 		dev->ud_subdevs = kmem_alloc(sizeof(dv), KM_SLEEP);
 		if (dev->ud_subdevs == NULL)
@@ -978,8 +980,10 @@ usbd_attachinterfaces(device_t parent, s
 			    loc != uiaa.uiaa_ifaceno)
 				continue;
 		}
+		KERNEL_LOCK(1, NULL);
 		dv = config_found_sm_loc(parent, "usbifif", ilocs, &uiaa,
 					 usbd_ifprint, config_stdsubmatch);
+		KERNEL_UNLOCK_ONE(NULL);
 		if (!dv)
 			continue;