Index: sys/x86/include/xen/xen-os.h
===================================================================
--- sys/x86/include/xen/xen-os.h
+++ sys/x86/include/xen/xen-os.h
@@ -43,6 +43,9 @@
 /* If non-zero, the hypervisor has been configured to use a direct vector */
 extern int xen_vector_callback_enabled;
 
+/* from 27c36a12f1584b53d2454dac238eeed3dedc82ba */
+extern bool xen_evtchn_needs_ack;
+
 /* tunable for disabling PV disks */
 extern int xen_disable_pv_disks;
 
Index: sys/x86/xen/xen_intr.c
===================================================================
--- sys/x86/xen/xen_intr.c
+++ sys/x86/xen/xen_intr.c
@@ -59,7 +59,6 @@
 #include <machine/xen/synch_bitops.h>
 
 #include <xen/xen-os.h>
-#include <xen/hvm.h>
 #include <xen/hypervisor.h>
 #include <xen/xen_intr.h>
 #include <xen/evtchn/evtchnvar.h>
Index: sys/xen/hvm.h
===================================================================
--- sys/xen/hvm.h
+++ sys/xen/hvm.h
@@ -105,6 +105,5 @@
 void xen_handle_shared_info(const void *__unused);
 
 extern uint32_t hvm_start_flags;
-extern bool xen_evtchn_needs_ack;
 
 #endif	/* __XEN_HVM_H__ */