Index: sys/dev/xen/console/xen_console.c
===================================================================
--- sys/dev/xen/console/xen_console.c
+++ sys/dev/xen/console/xen_console.c
@@ -55,6 +55,7 @@
 #include <xen/hypervisor.h>
 #include <xen/xen_intr.h>
 #include <xen/interface/io/console.h>
+#include <xen/hvm.h>
 
 #include "opt_ddb.h"
 #include "opt_printf.h"
@@ -272,6 +273,14 @@
 static void
 xencons_early_init_ring(struct xencons_priv *cons)
 {
+	/*
+	 * The ring is initialized later for the HVM console as the
+	 * pmap code is not yet fully initialized
+	 * TODO: See if we can map the ring in another way earlier.
+	 */
+	if (!xen_hvm_domain())
+		return;
+
 	cons->intf = pmap_mapdev_attr(ptoa(xen_get_console_mfn()), PAGE_SIZE,
 	    VM_MEMATTR_XEN);
 	cons->evtchn = xen_get_console_evtchn();
@@ -282,9 +291,23 @@
 {
 	struct xencons_priv *cons;
 	int err;
+	xen_pfn_t pfn;
 
 	cons = tty_softc(tp);
 
+	/*
+	 * The information are already retrieved in
+	 * xencons_early_init_ring for PV guest
+	 */
+	if (xen_hvm_domain()) {
+		cons->evtchn = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN);
+		pfn = hvm_get_parameter(HVM_PARAM_CONSOLE_PFN);
+		if (!pfn)
+			return (ENODEV);
+		cons->intf = pmap_mapdev_attr(pfn << PAGE_SHIFT, PAGE_SIZE,
+		    VM_MEMATTR_XEN);
+	}
+
 	if (cons->evtchn == 0)
 		return (ENODEV);
 
@@ -327,6 +350,10 @@
 
 	xencons_lock_assert(cons);
 
+	/* The console page may have not yet been initialized for HVM domain */
+	if (__predict_false(!intf))
+		return -1;
+
 	wcons = intf->out_cons;
 	wprod = intf->out_prod;
 
@@ -359,6 +386,10 @@
 
 	xencons_lock_assert(cons);
 
+	/* The console page may have not yet been initialized for HVM domain */
+	if (__predict_false(!intf))
+		return 0;
+
 	rcons = intf->in_cons;
 	rprod = intf->in_prod;
 	rmb();