FreeBSD 9.2 XEN xenbusb_nop_confighook_cb

Recently I tried run FreeBSD 9.2 on my Citrix Xen machine with HVM support. After booting I got error: xenbusb_nop_confighook_cb This error got me confused. I'd searched awhile and found solution : http://web.archiveorange.com/archive/v/jbzpKsnhTPhFFEuQuYTP

root@pruebas:/root # diff -u /usr/src/sys/kern/subr_autoconf.c-defecto /usr/src/sys/kern/subr_autoconf.c
--- /usr/src/sys/kern/subr_autoconf.c-defecto	2012-10-10 13:51:27.000000000 +0200
+++ /usr/src/sys/kern/subr_autoconf.c	2012-10-10 18:21:51.000000000 +0200
@@ -133,16 +133,17 @@
 	/* Block boot processing until all hooks are disestablished. */
 	mtx_lock(&intr_config_hook_lock);
 	warned = 0;
-	while (!TAILQ_EMPTY(&intr_config_hook_list)) {
+	/* while (!TAILQ_EMPTY(&intr_config_hook_list)) { */
 		if (msleep(&intr_config_hook_list, &intr_config_hook_lock,
 		    0, "conifhk", WARNING_INTERVAL_SECS * hz) ==
 		    EWOULDBLOCK) {
+			printf("\n\n SARENET Individual lock name antes de unlock es : %s", intr_config_hook_lock.lock_object.lo_name);
 			mtx_unlock(&intr_config_hook_lock);
 			warned++;
 			run_interrupt_driven_config_hooks_warning(warned);
 			mtx_lock(&intr_config_hook_lock);
 		}
-	}
+	/* } */
 	mtx_unlock(&intr_config_hook_lock);
 }TAILQ_EMPTY is at queue.h : 

#define	STAILQ_EMPTY(head)	((head)->stqh_first == NULL)