From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9268DC5ACCC for ; Thu, 18 Oct 2018 18:06:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4F6AF2148D for ; Thu, 18 Oct 2018 18:06:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="jp09aiK4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4F6AF2148D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730582AbeJSCJB (ORCPT ); Thu, 18 Oct 2018 22:09:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:58314 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729925AbeJSCJB (ORCPT ); Thu, 18 Oct 2018 22:09:01 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5A9E4204FD; Thu, 18 Oct 2018 18:06:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539886013; bh=Dc/JuhonEwyxFPxYoRu1Fc+zFKcLZOQY3MUCRSL0ZLE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jp09aiK4vSHJFYwlNpus9Z5Sb4sJGf0kWY1w0ejKX70bhtBZxGAwxy/VYgqjmZ7Rd yHrop/yd4axuZL29vrZUF8L5z0DWPmBUZ7/kneAfE1E5ziLNE+cY2GtCEk+WqvrOx5 tiSMyer2qARZDK3aOMBYtoedrLKWUT6EZPRHqmjo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "K. Y. Srinivasan" , Vitaly Kuznetsov , Dexuan Cui Subject: [PATCH 4.4 46/48] Drivers: hv: util: Pass the channel information during the init call Date: Thu, 18 Oct 2018 19:55:21 +0200 Message-Id: <20181018175430.353000104@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181018175427.133690306@linuxfoundation.org> References: <20181018175427.133690306@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: K. Y. Srinivasan commit b9830d120cbe155863399f25eaef6aa8353e767f upstream. Pass the channel information to the util drivers that need to defer reading the channel while they are processing a request. This would address the following issue reported by Vitaly: Commit 3cace4a61610 ("Drivers: hv: utils: run polling callback always in interrupt context") removed direct *_transaction.state = HVUTIL_READY assignments from *_handle_handshake() functions introducing the following race: if a userspace daemon connects before we get first non-negotiation request from the server hv_poll_channel() won't set transaction state to HVUTIL_READY as (!channel) condition will fail, we set it to non-NULL on the first real request from the server. Signed-off-by: K. Y. Srinivasan Reported-by: Vitaly Kuznetsov Signed-off-by: Dexuan Cui Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv_fcopy.c | 2 +- drivers/hv/hv_kvp.c | 2 +- drivers/hv/hv_snapshot.c | 2 +- drivers/hv/hv_util.c | 1 + include/linux/hyperv.h | 1 + 5 files changed, 5 insertions(+), 3 deletions(-) --- a/drivers/hv/hv_fcopy.c +++ b/drivers/hv/hv_fcopy.c @@ -256,7 +256,6 @@ void hv_fcopy_onchannelcallback(void *co */ fcopy_transaction.recv_len = recvlen; - fcopy_transaction.recv_channel = channel; fcopy_transaction.recv_req_id = requestid; fcopy_transaction.fcopy_msg = fcopy_msg; @@ -323,6 +322,7 @@ static void fcopy_on_reset(void) int hv_fcopy_init(struct hv_util_service *srv) { recv_buffer = srv->recv_buffer; + fcopy_transaction.recv_channel = srv->channel; init_completion(&release_event); /* --- a/drivers/hv/hv_kvp.c +++ b/drivers/hv/hv_kvp.c @@ -640,7 +640,6 @@ void hv_kvp_onchannelcallback(void *cont */ kvp_transaction.recv_len = recvlen; - kvp_transaction.recv_channel = channel; kvp_transaction.recv_req_id = requestid; kvp_transaction.kvp_msg = kvp_msg; @@ -690,6 +689,7 @@ int hv_kvp_init(struct hv_util_service *srv) { recv_buffer = srv->recv_buffer; + kvp_transaction.recv_channel = srv->channel; init_completion(&release_event); /* --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -264,7 +264,6 @@ void hv_vss_onchannelcallback(void *cont */ vss_transaction.recv_len = recvlen; - vss_transaction.recv_channel = channel; vss_transaction.recv_req_id = requestid; vss_transaction.msg = (struct hv_vss_msg *)vss_msg; @@ -340,6 +339,7 @@ hv_vss_init(struct hv_util_service *srv) return -ENOTSUPP; } recv_buffer = srv->recv_buffer; + vss_transaction.recv_channel = srv->channel; /* * When this driver loads, the user level daemon that --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -326,6 +326,7 @@ static int util_probe(struct hv_device * srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL); if (!srv->recv_buffer) return -ENOMEM; + srv->channel = dev->channel; if (srv->util_init) { ret = srv->util_init(srv); if (ret) { --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -1179,6 +1179,7 @@ int vmbus_allocate_mmio(struct resource struct hv_util_service { u8 *recv_buffer; + void *channel; void (*util_cb)(void *); int (*util_init)(struct hv_util_service *); void (*util_deinit)(void);