From faaba341e529d89c60f7a19e9131220d6b61744a Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@FreeBSD.org>
Date: Mon, 28 Nov 2016 04:53:36 +0000
Subject: [PATCH] hyperv/vmbus: Zero out GPADL if error happens.

MFC after:	1 week
Sponsored by:	Microsoft
Differential Revision:	https://reviews.freebsd.org/D8601
---
 sys/dev/hyperv/vmbus/vmbus_chan.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/sys/dev/hyperv/vmbus/vmbus_chan.c b/sys/dev/hyperv/vmbus/vmbus_chan.c
index 18f83aa5dbbc..0118439ba1e5 100644
--- a/sys/dev/hyperv/vmbus/vmbus_chan.c
+++ b/sys/dev/hyperv/vmbus/vmbus_chan.c
@@ -502,6 +502,12 @@ vmbus_chan_gpadl_connect(struct vmbus_channel *chan, bus_addr_t paddr,
 	int page_count, range_len, i, cnt, error;
 	uint64_t page_id;
 
+	/*
+	 * Reset GPADL, so that the result would consistent, if error
+	 * happened later on.
+	 */
+	*gpadl0 = 0;
+
 	/*
 	 * Preliminary checks.
 	 */