From: Long Li Date: Wed, 5 Oct 2016 23:57:46 +0000 (-0700) Subject: hv: do not lose pending heartbeat vmbus packets X-Git-Tag: firefly_0821_release~176^2~4^2~19^2~41 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fde4a5f237ab58fb1f2ec2d0405292eb4a04dff4;p=firefly-linux-kernel-4.4.55.git hv: do not lose pending heartbeat vmbus packets commit 407a3aee6ee2d2cb46d9ba3fc380bc29f35d020c upstream. 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c index 7994ec2e4151..41f5896224bd 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)];