From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:44995 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932245AbcILRGq (ORCPT ); Mon, 12 Sep 2016 13:06:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Olaf Hering , "K. Y. Srinivasan" , Sasha Levin Subject: [PATCH 4.4 038/192] [PATCH 039/135] Drivers: hv: vss: run only on supported host versions Date: Mon, 12 Sep 2016 18:59:07 +0200 Message-Id: <20160912152200.519151225@linuxfoundation.org> In-Reply-To: <20160912152158.855601725@linuxfoundation.org> References: <20160912152158.855601725@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit ed9ba608e4851144af8c7061cbb19f751c73e998 ] The Backup integration service on WS2012 has appearently trouble to negotiate with a guest which does not support the provided util version. Currently the VSS driver supports only version 5/0. A WS2012 offers only version 1/x and 3/x, and vmbus_prep_negotiate_resp correctly returns an empty icframe_vercnt/icmsg_vercnt. But the host ignores that and continues to send ICMSGTYPE_NEGOTIATE messages. The result are weird errors during boot and general misbehaviour. Check the Windows version to work around the host bug, skip hv_vss_init on WS2012 and older. Signed-off-by: Olaf Hering Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv_snapshot.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -331,6 +331,11 @@ static void vss_on_reset(void) int hv_vss_init(struct hv_util_service *srv) { + if (vmbus_proto_version < VERSION_WIN8_1) { + pr_warn("Integration service 'Backup (volume snapshot)'" + " not supported on this host version.\n"); + return -ENOTSUPP; + } recv_buffer = srv->recv_buffer; /*