3 files changed, 46 insertions, 20 deletions

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 6c8c4d340930..2b8b8d4558d2 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -46,37 +46,59 @@ struct vmbus_channel_message_table_entry {
  *
  * @icmsghdrp is of type &struct icmsg_hdr.
  * @negop is of type &struct icmsg_negotiate.
- * Set up and fill in default negotiate response message. This response can
- * come from both the vmbus driver and the hv_utils driver. The current api
- * will respond properly to both Windows 2008 and Windows 2008-R2 operating
- * systems.
+ * Set up and fill in default negotiate response message.
+ *
+ * The max_fw_version specifies the maximum framework version that
+ * we can support and max _srv_version specifies the maximum service
+ * version we can support. A special value MAX_SRV_VER can be
+ * specified to indicate that we can handle the maximum version
+ * exposed by the host.
  *
  * Mainly used by Hyper-V drivers.
  */
 void vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
-                               struct icmsg_negotiate *negop, u8 *buf)
+                                struct icmsg_negotiate *negop, u8 *buf,
+                                int max_fw_version, int max_srv_version)
 {
+        int icframe_vercnt;
+        int icmsg_vercnt;
+        int i;
+
         icmsghdrp->icmsgsize = 0x10;
 
         negop = (struct icmsg_negotiate *)&buf[
                 sizeof(struct vmbuspipe_hdr) +
                 sizeof(struct icmsg_hdr)];
 
-        if (negop->icframe_vercnt == 2 &&
-           negop->icversion_data[1].major == 3) {
-                negop->icversion_data[0].major = 3;
-                negop->icversion_data[0].minor = 0;
-                negop->icversion_data[1].major = 3;
-                negop->icversion_data[1].minor = 0;
-        } else {
-                negop->icversion_data[0].major = 1;
-                negop->icversion_data[0].minor = 0;
-                negop->icversion_data[1].major = 1;
-                negop->icversion_data[1].minor = 0;
+        icframe_vercnt = negop->icframe_vercnt;
+        icmsg_vercnt = negop->icmsg_vercnt;
+
+        /*
+         * Select the framework version number we will
+         * support.
+         */
+
+        for (i = 0; i < negop->icframe_vercnt; i++) {
+                if (negop->icversion_data[i].major <= max_fw_version)
+                        icframe_vercnt = negop->icversion_data[i].major;
+        }
+
+        for (i = negop->icframe_vercnt;
+                 (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) {
+                if (negop->icversion_data[i].major <= max_srv_version)
+                        icmsg_vercnt = negop->icversion_data[i].major;
         }
 
+        /*
+         * Respond with the maximum framework and service
+         * version numbers we can support.
+         */
         negop->icframe_vercnt = 1;
         negop->icmsg_vercnt = 1;
+        negop->icversion_data[0].major = icframe_vercnt;
+        negop->icversion_data[0].minor = 0;
+        negop->icversion_data[1].major = icmsg_vercnt;
+        negop->icversion_data[1].minor = 0;
 }
 
 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
index 6186025209ce..0012eed6d872 100644
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -394,7 +394,8 @@ void hv_kvp_onchannelcallback(void *context)
                         sizeof(struct vmbuspipe_hdr)];
 
                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-                        vmbus_prep_negotiate_resp(icmsghdrp, negop, recv_buffer);
+                        vmbus_prep_negotiate_resp(icmsghdrp, negop,
+                                 recv_buffer, MAX_SRV_VER, MAX_SRV_VER);
                 } else {
                         kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
                                 sizeof(struct vmbuspipe_hdr) +
diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index dbb8b8eec210..d3ac6a40118b 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -70,7 +70,8 @@ static void shutdown_onchannelcallback(void *context)
                         sizeof(struct vmbuspipe_hdr)];
 
                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-                        vmbus_prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf);
+                        vmbus_prep_negotiate_resp(icmsghdrp, negop,
+                                        shut_txf_buf, MAX_SRV_VER, MAX_SRV_VER);
                 } else {
                         shutdown_msg =
                                 (struct shutdown_msg_data *)&shut_txf_buf[
@@ -195,7 +196,8 @@ static void timesync_onchannelcallback(void *context)
                                 sizeof(struct vmbuspipe_hdr)];
 
                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-                        vmbus_prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf);
+                        vmbus_prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf,
+                                                MAX_SRV_VER, MAX_SRV_VER);
                 } else {
                         timedatap = (struct ictimesync_data *)&time_txf_buf[
                                 sizeof(struct vmbuspipe_hdr) +
@@ -234,7 +236,8 @@ static void heartbeat_onchannelcallback(void *context)
                                 sizeof(struct vmbuspipe_hdr)];
 
                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-                        vmbus_prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf);
+                        vmbus_prep_negotiate_resp(icmsghdrp, NULL,
+                                hbeat_txf_buf, MAX_SRV_VER, MAX_SRV_VER);
                 } else {
                         heartbeat_msg =
                                 (struct heartbeat_msg_data *)&hbeat_txf_buf[