From 1f7ff6f7910efeb370e8382bfd15e8acb1dcf003 Mon Sep 17 00:00:00 2001 From: Long Li Date: Wed, 5 Oct 2016 16:57:46 -0700 Subject: [PATCH] hv: do not lose pending heartbeat vmbus packets [ Upstream commit 407a3aee6ee2d2cb46d9ba3fc380bc29f35d020c ] 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 Signed-off-by: K. Y. Srinivasan CC: Stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/hv/hv_util.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c index 7994ec2..41f5896 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)]; -- 2.7.4