[3.13.y.z extended stable] Patch "Drivers: hv: vmbus: Negotiate version 3.0 when running on ws2012r2 hosts" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    Drivers: hv: vmbus: Negotiate version 3.0 when running on ws2012r2 hosts

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.3.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 6b4b3abb3ae3a97280014406df5f322f5c7bfb9f Mon Sep 17 00:00:00 2001
From: "K. Y. Srinivasan" <kys at microsoft.com>
Date: Thu, 3 Apr 2014 18:02:45 -0700
Subject: Drivers: hv: vmbus: Negotiate version 3.0 when running on ws2012r2
 hosts

commit 03367ef5ea811475187a0732aada068919e14d61 upstream.

Only ws2012r2 hosts support the ability to reconnect to the host on VMBUS. This functionality
is needed by kexec in Linux. To use this functionality we need to negotiate version 3.0 of the
VMBUS protocol.

Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/hv/connection.c | 5 ++++-
 include/linux/hyperv.h  | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index f2d7bf9..2e7801a 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -55,6 +55,9 @@ static __u32 vmbus_get_next_version(__u32 current_version)
 	case (VERSION_WIN8):
 		return VERSION_WIN7;

+	case (VERSION_WIN8_1):
+		return VERSION_WIN8;
+
 	case (VERSION_WS2008):
 	default:
 		return VERSION_INVAL;
@@ -77,7 +80,7 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
 	msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
 	msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]);
 	msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]);
-	if (version == VERSION_WIN8)
+	if (version == VERSION_WIN8_1)
 		msg->target_vcpu = hv_context.vp_index[smp_processor_id()];

 	/*
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 344883d..6088058 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -464,15 +464,17 @@ hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi,
  * 0 . 13 (Windows Server 2008)
  * 1 . 1  (Windows 7)
  * 2 . 4  (Windows 8)
+ * 3 . 0  (Windows 8 R2)
  */

 #define VERSION_WS2008  ((0 << 16) | (13))
 #define VERSION_WIN7    ((1 << 16) | (1))
 #define VERSION_WIN8    ((2 << 16) | (4))
+#define VERSION_WIN8_1    ((3 << 16) | (0))

 #define VERSION_INVAL -1

-#define VERSION_CURRENT VERSION_WIN8
+#define VERSION_CURRENT VERSION_WIN8_1

 /* Make maximum size of pipe payload of 16K */
 #define MAX_PIPE_DATA_PAYLOAD		(sizeof(u8) * 16384)
--
1.9.1