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.

This patch has been backported to apply against the 3.12 stable tree.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>        [3.9+]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index d6b1e29b0ad26e2300abce4abd7a8f6942af11bf..8dd98d4fc124605078aa6dc843258b13c8879b6b 100644 (file)
--- 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;
@@ -79,7 +82,7 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
        msg->monitor_page2 = virt_to_phys(
                        (void *)((unsigned long)vmbus_connection.monitor_pages +
                                 PAGE_SIZE));
-       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 1835c615948c0c0f7582e2ff103ec14d7715cdd2..b6043a0c629f484355c2eea4ac21d8db06746eec 100644 (file)
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -473,15 +473,18 @@ 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)