Commit 407a3aee authored Oct 05, 2016 by Long Li Committed by Greg Kroah-Hartman Oct 25, 2016

hv: do not lose pending heartbeat vmbus packets



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>

parent 43605e29

drivers/hv/hv_util.c

+7 −3

Original line number	Diff line number	Diff line
		@@ -314,10 +314,14 @@ static void heartbeat_onchannelcallback(void *context)
		u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
		struct icmsg_negotiate *negop = NULL;

		while (1) {

		vmbus_recvpacket(channel, hbeat_txf_buf,
		PAGE_SIZE, &recvlen, &requestid);

		if (recvlen > 0) {
		if (!recvlen)
		break;

		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
		sizeof(struct vmbuspipe_hdr)];