From 496d023db35fdfd9312d8fda9dd2bcc4922b0f9d Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@FreeBSD.org>
Date: Mon, 30 May 2016 09:44:17 +0000
Subject: [PATCH] hyperv/et: Allow Hyper-V event timer be disabled

MFC after:	1 week
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D6599
---
 sys/dev/hyperv/vmbus/hv_et.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sys/dev/hyperv/vmbus/hv_et.c b/sys/dev/hyperv/vmbus/hv_et.c
index 3aaf5baa139..6e3fbfda402 100644
--- a/sys/dev/hyperv/vmbus/hv_et.c
+++ b/sys/dev/hyperv/vmbus/hv_et.c
@@ -113,6 +113,9 @@ vmbus_et_identify(driver_t *driver, device_t parent)
 static int
 vmbus_et_probe(device_t dev)
 {
+	if (resource_disabled(VMBUS_ET_NAME, 0))
+		return (ENXIO);
+
 	device_set_desc(dev, "Hyper-V event timer");
 
 	return (BUS_PROBE_NOWILDCARD);