From: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: Sat, 1 Aug 2015 23:08:19 +0000 (-0700)
Subject: Drivers: hv: vmbus: don't send CHANNELMSG_UNLOAD on pre-Win2012R2 hosts
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4a54243fc08f0edda1303bb666f0da68c378c036;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

Drivers: hv: vmbus: don't send CHANNELMSG_UNLOAD on pre-Win2012R2 hosts

Pre-Win2012R2 hosts don't properly handle CHANNELMSG_UNLOAD and
wait_for_completion() hangs. Avoid sending such request on old hosts.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 4506a6623618..00ba3f36f193 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -469,6 +469,10 @@ void vmbus_initiate_unload(void)
 {
 	struct vmbus_channel_message_header hdr;
 
+	/* Pre-Win2012R2 hosts don't support reconnect */
+	if (vmbus_proto_version < VERSION_WIN8_1)
+		return;
+
 	init_completion(&vmbus_connection.unload_event);
 	memset(&hdr, 0, sizeof(struct vmbus_channel_message_header));
 	hdr.msgtype = CHANNELMSG_UNLOAD;