diff mbox

[SRU,Trusty,Vivid,Xenial,Yakkety,1/1] hv: do not lose pending heartbeat vmbus packets

Message ID 45ad3ec334c7027f574bc33163f1843c936526cc.1478809399.git.joseph.salisbury@canonical.com
State New
Headers show

Commit Message

Joseph Salisbury Nov. 10, 2016, 8:51 p.m. UTC 
From: Long Li <longli@microsoft.com>

BugLink: http://bugs.launchpad.net/bugs/1632786

The host keeps sending heartbeat packets independent of the
guest responding to them.  Even though we respond to the heartbeat messages at
interrupt level, we can have situations where there maybe multiple heartbeat
messages pending that have not been responded to. For instance this occurs when the
VM is paused and the host continues to send the heartbeat messages.
Address this issue by draining and responding to all
the heartbeat messages that maybe pending.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 407a3aee6ee2d2cb46d9ba3fc380bc29f35d020c)
Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
---
 drivers/hv/hv_util.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

Comments

Tim Gardner Nov. 11, 2016, 1:59 p.m. UTC | #1
Stefan Bader Nov. 15, 2016, 8:48 a.m. UTC | #2
diff mbox

Patch

diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index d5acaa2..9dc6372 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -283,10 +283,14 @@  static void heartbeat_onchannelcallback(void *context)
 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
 	struct icmsg_negotiate *negop = NULL;
 
-	vmbus_recvpacket(channel, hbeat_txf_buf,
-			 PAGE_SIZE, &recvlen, &requestid);
+	while (1) {
+
+		vmbus_recvpacket(channel, hbeat_txf_buf,
+				 PAGE_SIZE, &recvlen, &requestid);
+
+		if (!recvlen)
+			break;
 
-	if (recvlen > 0) {
 		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 				sizeof(struct vmbuspipe_hdr)];