releases/3.10.59/drivers-hv-vmbus-cleanup-vmbus_post_msg.patch

From fdeebcc62279119dbeafbc1a2e39e773839025fd Mon Sep 17 00:00:00 2001
From: "K. Y. Srinivasan" <kys@microsoft.com>
Date: Wed, 27 Aug 2014 16:25:31 -0700
Subject: Drivers: hv: vmbus: Cleanup vmbus_post_msg()

From: "K. Y. Srinivasan" <kys@microsoft.com>

commit fdeebcc62279119dbeafbc1a2e39e773839025fd upstream.

Posting messages to the host can fail because of transient resource
related failures. Correctly deal with these failures and increase the
number of attempts to post the message before giving up.

In this version of the patch, I have normalized the error code to
Linux error code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/hv/connection.c |   17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -393,10 +393,21 @@ int vmbus_post_msg(void *buffer, size_t
 	 * insufficient resources. Retry the operation a couple of
 	 * times before giving up.
 	 */
-	while (retries < 3) {
-		ret =  hv_post_message(conn_id, 1, buffer, buflen);
-		if (ret != HV_STATUS_INSUFFICIENT_BUFFERS)
+	while (retries < 10) {
+		ret = hv_post_message(conn_id, 1, buffer, buflen);
+
+		switch (ret) {
+		case HV_STATUS_INSUFFICIENT_BUFFERS:
+			ret = -ENOMEM;
+		case -ENOMEM:
+			break;
+		case HV_STATUS_SUCCESS:
 			return ret;
+		default:
+			pr_err("hv_post_msg() failed; error code:%d\n", ret);
+			return -EINVAL;
+		}
+
 		retries++;
 		msleep(100);
 	}