Index: head/sys/dev/hyperv/include/hyperv.h
===================================================================
--- head/sys/dev/hyperv/include/hyperv.h
+++ head/sys/dev/hyperv/include/hyperv.h
@@ -538,6 +538,7 @@
 	struct vmbus_softc		*vmbus_sc;
 	hv_vmbus_channel_state		state;
 	hv_vmbus_channel_offer_channel	offer_msg;
+	uint32_t			ch_id;		/* channel id */
 	/*
 	 * These are based on the offer_msg.monitor_id.
 	 * Save it here for easy access.
Index: head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c
===================================================================
--- head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c
+++ head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c
@@ -2953,7 +2953,7 @@
 	chan->hv_chan_rxr = rxr;
 	if (bootverbose) {
 		if_printf(sc->hn_ifp, "link RX ring %d to channel%u\n",
-		    idx, chan->offer_msg.child_rel_id);
+		    idx, chan->ch_id);
 	}
 
 	if (idx < sc->hn_tx_ring_inuse) {
@@ -2967,7 +2967,7 @@
 		txr->hn_chan = chan;
 		if (bootverbose) {
 			if_printf(sc->hn_ifp, "link TX ring %d to channel%u\n",
-			    idx, chan->offer_msg.child_rel_id);
+			    idx, chan->ch_id);
 		}
 	}
 
Index: head/sys/dev/hyperv/vmbus/hv_channel.c
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_channel.c
+++ head/sys/dev/hyperv/vmbus/hv_channel.c
@@ -62,7 +62,7 @@
 vmbus_channel_set_event(hv_vmbus_channel *channel)
 {
 	struct vmbus_softc *sc = channel->vmbus_sc;
-	uint32_t chanid = channel->offer_msg.child_rel_id;
+	uint32_t chanid = channel->ch_id;
 
 	atomic_set_long(&sc->vmbus_tx_evtflags[chanid >> VMBUS_EVTFLAG_SHIFT],
 	    1UL << (chanid & VMBUS_EVTFLAG_MASK));
@@ -107,10 +107,10 @@
 
 	if (primary_ch == NULL) {
 		dev = channel->device->device;
-		ch_id = channel->offer_msg.child_rel_id;
+		ch_id = channel->ch_id;
 	} else {
 		dev = primary_ch->device->device;
-		ch_id = primary_ch->offer_msg.child_rel_id;
+		ch_id = primary_ch->ch_id;
 		sub_ch_id = channel->offer_msg.offer.sub_channel_index;
 	}
 	ctx = &channel->ch_sysctl_ctx;
@@ -136,7 +136,7 @@
 
 		SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(devch_id_sysctl),
 		    OID_AUTO, "chanid", CTLFLAG_RD,
-		    &channel->offer_msg.child_rel_id, 0, "channel id");
+		    &channel->ch_id, 0, "channel id");
 	}
 	SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(devch_id_sysctl), OID_AUTO,
 	    "cpu", CTLFLAG_RD, &channel->target_cpu, 0, "owner CPU id");
@@ -190,7 +190,7 @@
 	if (user_data_len > VMBUS_CHANMSG_CHOPEN_UDATA_SIZE) {
 		device_printf(sc->vmbus_dev,
 		    "invalid udata len %u for chan%u\n",
-		    user_data_len, new_channel->offer_msg.child_rel_id);
+		    user_data_len, new_channel->ch_id);
 		return EINVAL;
 	}
 
@@ -261,14 +261,14 @@
 	if (mh == NULL) {
 		device_printf(sc->vmbus_dev,
 		    "can not get msg hypercall for chopen(chan%u)\n",
-		    new_channel->offer_msg.child_rel_id);
+		    new_channel->ch_id);
 		return ENXIO;
 	}
 
 	req = vmbus_msghc_dataptr(mh);
 	req->chm_hdr.chm_type = VMBUS_CHANMSG_TYPE_CHOPEN;
-	req->chm_chanid = new_channel->offer_msg.child_rel_id;
-	req->chm_openid = new_channel->offer_msg.child_rel_id;
+	req->chm_chanid = new_channel->ch_id;
+	req->chm_openid = new_channel->ch_id;
 	req->chm_gpadl = new_channel->ring_buffer_gpadl_handle;
 	req->chm_vcpuid = new_channel->target_vcpu;
 	req->chm_rxbr_pgofs = send_ring_buffer_size >> PAGE_SHIFT;
@@ -279,7 +279,7 @@
 	if (ret != 0) {
 		device_printf(sc->vmbus_dev,
 		    "chopen(chan%u) msg hypercall exec failed: %d\n",
-		    new_channel->offer_msg.child_rel_id, ret);
+		    new_channel->ch_id, ret);
 		vmbus_msghc_put(sc, mh);
 		return ret;
 	}
@@ -294,11 +294,11 @@
 		new_channel->state = HV_CHANNEL_OPENED_STATE;
 		if (bootverbose) {
 			device_printf(sc->vmbus_dev, "chan%u opened\n",
-			    new_channel->offer_msg.child_rel_id);
+			    new_channel->ch_id);
 		}
 	} else {
 		device_printf(sc->vmbus_dev, "failed to open chan%u\n",
-		    new_channel->offer_msg.child_rel_id);
+		    new_channel->ch_id);
 		ret = ENXIO;
 	}
 	return (ret);
@@ -369,13 +369,13 @@
 	if (mh == NULL) {
 		device_printf(sc->vmbus_dev,
 		    "can not get msg hypercall for gpadl->chan%u\n",
-		    channel->offer_msg.child_rel_id);
+		    channel->ch_id);
 		return EIO;
 	}
 
 	req = vmbus_msghc_dataptr(mh);
 	req->chm_hdr.chm_type = VMBUS_CHANMSG_TYPE_GPADL_CONN;
-	req->chm_chanid = channel->offer_msg.child_rel_id;
+	req->chm_chanid = channel->ch_id;
 	req->chm_gpadl = gpadl;
 	req->chm_range_len = range_len;
 	req->chm_range_cnt = 1;
@@ -388,7 +388,7 @@
 	if (error) {
 		device_printf(sc->vmbus_dev,
 		    "gpadl->chan%u msg hypercall exec failed: %d\n",
-		    channel->offer_msg.child_rel_id, error);
+		    channel->ch_id, error);
 		vmbus_msghc_put(sc, mh);
 		return error;
 	}
@@ -424,12 +424,12 @@
 
 	if (status != 0) {
 		device_printf(sc->vmbus_dev, "gpadl->chan%u failed: "
-		    "status %u\n", channel->offer_msg.child_rel_id, status);
+		    "status %u\n", channel->ch_id, status);
 		return EIO;
 	} else {
 		if (bootverbose) {
 			device_printf(sc->vmbus_dev, "gpadl->chan%u "
-			    "succeeded\n", channel->offer_msg.child_rel_id);
+			    "succeeded\n", channel->ch_id);
 		}
 	}
 	return 0;
@@ -450,20 +450,20 @@
 	if (mh == NULL) {
 		device_printf(sc->vmbus_dev,
 		    "can not get msg hypercall for gpa x->chan%u\n",
-		    chan->offer_msg.child_rel_id);
+		    chan->ch_id);
 		return EBUSY;
 	}
 
 	req = vmbus_msghc_dataptr(mh);
 	req->chm_hdr.chm_type = VMBUS_CHANMSG_TYPE_GPADL_DISCONN;
-	req->chm_chanid = chan->offer_msg.child_rel_id;
+	req->chm_chanid = chan->ch_id;
 	req->chm_gpadl = gpadl;
 
 	error = vmbus_msghc_exec(sc, mh);
 	if (error) {
 		device_printf(sc->vmbus_dev,
 		    "gpa x->chan%u msg hypercall exec failed: %d\n",
-		    chan->offer_msg.child_rel_id, error);
+		    chan->ch_id, error);
 		vmbus_msghc_put(sc, mh);
 		return error;
 	}
@@ -502,13 +502,13 @@
 	if (mh == NULL) {
 		device_printf(sc->vmbus_dev,
 		    "can not get msg hypercall for chclose(chan%u)\n",
-		    channel->offer_msg.child_rel_id);
+		    channel->ch_id);
 		return;
 	}
 
 	req = vmbus_msghc_dataptr(mh);
 	req->chm_hdr.chm_type = VMBUS_CHANMSG_TYPE_CHCLOSE;
-	req->chm_chanid = channel->offer_msg.child_rel_id;
+	req->chm_chanid = channel->ch_id;
 
 	error = vmbus_msghc_exec_noresult(mh);
 	vmbus_msghc_put(sc, mh);
@@ -516,11 +516,11 @@
 	if (error) {
 		device_printf(sc->vmbus_dev,
 		    "chclose(chan%u) msg hypercall exec failed: %d\n",
-		    channel->offer_msg.child_rel_id, error);
+		    channel->ch_id, error);
 		return;
 	} else if (bootverbose) {
 		device_printf(sc->vmbus_dev, "close chan%u\n",
-		    channel->offer_msg.child_rel_id);
+		    channel->ch_id);
 	}
 
 	/* Tear down the gpadl for the channel's ring buffer */
@@ -957,7 +957,7 @@
 	volatile int *flag_cnt_ptr;
 	int flag_cnt;
 
-	flag_cnt = (chan->offer_msg.child_rel_id / VMBUS_EVTFLAG_LEN) + 1;
+	flag_cnt = (chan->ch_id / VMBUS_EVTFLAG_LEN) + 1;
 	flag_cnt_ptr = VMBUS_PCPU_PTR(sc, event_flags_cnt, chan->target_cpu);
 
 	for (;;) {
@@ -970,7 +970,7 @@
 			if (bootverbose) {
 				device_printf(sc->vmbus_dev,
 				    "channel%u update cpu%d flag_cnt to %d\n",
-				    chan->offer_msg.child_rel_id,
+				    chan->ch_id,
 				    chan->target_cpu, flag_cnt);
 			}
 			break;
Index: head/sys/dev/hyperv/vmbus/hv_channel_mgmt.c
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_channel_mgmt.c
+++ head/sys/dev/hyperv/vmbus/hv_channel_mgmt.c
@@ -112,7 +112,7 @@
 	hv_vmbus_channel*	channel;
 	uint32_t                relid;
 
-	relid = new_channel->offer_msg.child_rel_id;
+	relid = new_channel->ch_id;
 	/*
 	 * Make sure this is a new offer
 	 */
@@ -148,10 +148,10 @@
 		logstr[0] = '\0';
 		if (channel != NULL) {
 			snprintf(logstr, sizeof(logstr), ", primary chan%u",
-			    channel->offer_msg.child_rel_id);
+			    channel->ch_id);
 		}
 		device_printf(sc->vmbus_dev, "chan%u subchanid%u offer%s\n",
-		    new_channel->offer_msg.child_rel_id,
+		    new_channel->ch_id,
 		    new_channel->offer_msg.offer.sub_channel_index, logstr);
 	}
 
@@ -200,7 +200,7 @@
 		}
 
 		printf("VMBUS: duplicated primary channel%u\n",
-		    new_channel->offer_msg.child_rel_id);
+		    new_channel->ch_id);
 		hv_vmbus_free_vmbus_channel(new_channel);
 		return;
 	}
@@ -241,7 +241,7 @@
 
 	if (bootverbose) {
 		printf("vmbus_chan%u: assigned to cpu%u [vcpu%u]\n",
-		    chan->offer_msg.child_rel_id,
+		    chan->ch_id,
 		    chan->target_cpu, chan->target_vcpu);
 	}
 }
@@ -292,6 +292,7 @@
 
 	/* Allocate the channel object and save this offer */
 	new_channel = hv_vmbus_allocate_channel(sc);
+	new_channel->ch_id = offer->child_rel_id;
 
 	/*
 	 * By default we setup state to enable batched
@@ -379,13 +380,13 @@
 		if (mh == NULL) {
 			device_printf(sc->vmbus_dev,
 			    "can not get msg hypercall for chfree(chan%u)\n",
-			    chan->offer_msg.child_rel_id);
+			    chan->ch_id);
 			goto remove;
 		}
 
 		req = vmbus_msghc_dataptr(mh);
 		req->chm_hdr.chm_type = VMBUS_CHANMSG_TYPE_CHFREE;
-		req->chm_chanid = chan->offer_msg.child_rel_id;
+		req->chm_chanid = chan->ch_id;
 
 		error = vmbus_msghc_exec_noresult(mh);
 		vmbus_msghc_put(sc, mh);
@@ -393,12 +394,12 @@
 		if (error) {
 			device_printf(sc->vmbus_dev,
 			    "chfree(chan%u) failed: %d",
-			    chan->offer_msg.child_rel_id, error);
+			    chan->ch_id, error);
 			/* NOTE: Move on! */
 		} else {
 			if (bootverbose) {
 				device_printf(sc->vmbus_dev, "chan%u freed\n",
-				    chan->offer_msg.child_rel_id);
+				    chan->ch_id);
 			}
 		}
 remove: