Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753339AbcKYJDw (ORCPT ); Fri, 25 Nov 2016 04:03:52 -0500 Received: from mx2.suse.de ([195.135.220.15]:45254 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752264AbcKYIbB (ORCPT ); Fri, 25 Nov 2016 03:31:01 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Long Li , "K . Y . Srinivasan" , Jiri Slaby Subject: [PATCH 3.12 023/127] hv: do not lose pending heartbeat vmbus packets Date: Fri, 25 Nov 2016 09:28:56 +0100 Message-Id: <5ec8acb01c720a8522e5998814eead852dccb512.1480062521.git.jslaby@suse.cz> X-Mailer: git-send-email 2.10.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1545 Lines: 47 From: Long Li 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- 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 665b7dac6b7d..74d7025a05e6 100644 --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -276,10 +276,14 @@ 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)]; -- 2.10.2