Index: head/sys/dev/hyperv/include/vmbus.h
===================================================================
--- head/sys/dev/hyperv/include/vmbus.h
+++ head/sys/dev/hyperv/include/vmbus.h
@@ -172,6 +172,7 @@
 uint32_t	vmbus_chan_id(const struct vmbus_channel *chan);
 uint32_t	vmbus_chan_subidx(const struct vmbus_channel *chan);
 bool		vmbus_chan_is_primary(const struct vmbus_channel *chan);
+bool		vmbus_chan_is_revoked(const struct vmbus_channel *chan);
 const struct hyperv_guid *
 		vmbus_chan_guid_inst(const struct vmbus_channel *chan);
 int		vmbus_chan_prplist_nelem(int br_size, int prpcnt_max,
Index: head/sys/dev/hyperv/vmbus/vmbus_chan.c
===================================================================
--- head/sys/dev/hyperv/vmbus/vmbus_chan.c
+++ head/sys/dev/hyperv/vmbus/vmbus_chan.c
@@ -1220,7 +1220,7 @@
 	wakeup(prichan);
 done:
 	/*
-	 * Hook this channel up for later rescind.
+	 * Hook this channel up for later revocation.
 	 */
 	mtx_lock(&sc->vmbus_chan_lock);
 	vmbus_chan_ins_list(sc, newchan);
@@ -1368,7 +1368,7 @@
 
 	note = (const struct vmbus_chanmsg_chrescind *)msg->msg_data;
 	if (note->chm_chanid > VMBUS_CHAN_MAX) {
-		device_printf(sc->vmbus_dev, "invalid rescinded chan%u\n",
+		device_printf(sc->vmbus_dev, "invalid revoked chan%u\n",
 		    note->chm_chanid);
 		return;
 	}
@@ -1403,8 +1403,12 @@
 		mtx_unlock(&sc->vmbus_prichan_lock);
 	}
 
+	if (atomic_testandset_int(&chan->ch_stflags,
+	    VMBUS_CHAN_ST_REVOKED_SHIFT))
+		panic("channel has already been revoked");
+
 	if (bootverbose)
-		vmbus_chan_printf(chan, "chan%u rescinded\n", note->chm_chanid);
+		vmbus_chan_printf(chan, "chan%u revoked\n", note->chm_chanid);
 
 	/* Detach the target channel. */
 	taskqueue_enqueue(chan->ch_mgmt_tq, &chan->ch_detach_task);
@@ -1695,3 +1699,12 @@
 
 	return (chan->ch_mgmt_tq);
 }
+
+bool
+vmbus_chan_is_revoked(const struct vmbus_channel *chan)
+{
+
+	if (chan->ch_stflags & VMBUS_CHAN_ST_REVOKED)
+		return (true);
+	return (false);
+}
Index: head/sys/dev/hyperv/vmbus/vmbus_chanvar.h
===================================================================
--- head/sys/dev/hyperv/vmbus/vmbus_chanvar.h
+++ head/sys/dev/hyperv/vmbus/vmbus_chanvar.h
@@ -159,10 +159,12 @@
 #define VMBUS_CHAN_ST_ONPRIL_SHIFT	1
 #define VMBUS_CHAN_ST_ONSUBL_SHIFT	2
 #define VMBUS_CHAN_ST_ONLIST_SHIFT	3
+#define VMBUS_CHAN_ST_REVOKED_SHIFT	4	/* sticky */
 #define VMBUS_CHAN_ST_OPENED		(1 << VMBUS_CHAN_ST_OPENED_SHIFT)
 #define VMBUS_CHAN_ST_ONPRIL		(1 << VMBUS_CHAN_ST_ONPRIL_SHIFT)
 #define VMBUS_CHAN_ST_ONSUBL		(1 << VMBUS_CHAN_ST_ONSUBL_SHIFT)
 #define VMBUS_CHAN_ST_ONLIST		(1 << VMBUS_CHAN_ST_ONLIST_SHIFT)
+#define VMBUS_CHAN_ST_REVOKED		(1 << VMBUS_CHAN_ST_REVOKED_SHIFT)
 
 struct vmbus_softc;
 struct vmbus_message;