Index: sys/arch/amd64/amd64/db_interface.c
===================================================================
RCS file: /cvsroot/src/sys/arch/amd64/amd64/db_interface.c,v
retrieving revision 1.15
diff -u -p -r1.15 db_interface.c
--- sys/arch/amd64/amd64/db_interface.c	28 Nov 2007 16:28:43 -0000	1.15
+++ sys/arch/amd64/amd64/db_interface.c	19 Apr 2008 17:03:28 -0000
@@ -35,6 +35,7 @@
 #include <sys/cdefs.h>
 __KERNEL_RCSID(0, "$NetBSD: db_interface.c,v 1.15 2007/11/28 16:28:43 ad Exp $");
 
+#include "opt_xen.h"
 #include "opt_ddb.h"
 #include "opt_multiprocessor.h"
 
@@ -99,10 +100,20 @@ db_machine_init(void)
 {
 
 #ifdef MULTIPROCESSOR
+
+#if !defined(XEN)
 	ddb_vec = idt_vec_alloc(0xf0, 0xff);
 	setgate((struct gate_descriptor *)&idt[ddb_vec], &Xintrddb, 1,
 	    SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
+#else
+	xen_idt[xen_idt_idx].vector = 0xf0;
+	xen_idt[xen_idt_idx].flags = SEL_KPL;
+	xen_idt[xen_idt_idx].cs = GSEL(GCODE_SEL, SEL_KPL);
+	xen_idt[xen_idt_idx].address = (unsigned long) &Xintrddb;
+	xen_idt_idx++;
 #endif
+
+#endif /* MULTIPROCESSOR */
 }
 
 #ifdef MULTIPROCESSOR
Index: sys/arch/amd64/include/segments.h
===================================================================
RCS file: /cvsroot/src/sys/arch/amd64/include/segments.h,v
retrieving revision 1.18
diff -u -p -r1.18 segments.h
--- sys/arch/amd64/include/segments.h	19 Apr 2008 12:10:08 -0000	1.18
+++ sys/arch/amd64/include/segments.h	19 Apr 2008 17:03:29 -0000
@@ -218,7 +218,8 @@ struct region_descriptor {
 extern struct sys_segment_descriptor *ldt;
 #endif
 #ifdef XEN
-extern struct trap_info *idt;
+extern struct trap_info *xen_idt;
+extern int xen_idt_idx;
 #else
 extern struct gate_descriptor *idt;
 #endif