Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 218BFC433F5 for ; Mon, 15 Nov 2021 17:21:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07A28632B6 for ; Mon, 15 Nov 2021 17:21:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237506AbhKORWg (ORCPT ); Mon, 15 Nov 2021 12:22:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:47706 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236791AbhKORMr (ORCPT ); Mon, 15 Nov 2021 12:12:47 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 65BED61BF9; Mon, 15 Nov 2021 17:09:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636996191; bh=TDhxsyRUCBk/oFt2N3KLseCZVZ8NY9ReJr1yWJRh2DQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zd3acu9EEPXQ/DnTVxv1Tz/18MJebCdaa1H0Eq73qwl+t/wk8sSVimeR+u6bGWzbc Zj0ZLyvmhiirDm5mftdCb1+anopDniBV+vl4XY4ANIAaQ4/FgdkMZAJ5raRdM30j8L UC8OizjIMdZN8i83sB4xzTv5fze4vB5TlA9T3fJ8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Jin , Dongli Zhang , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 049/355] xen/netfront: stop tx queues during live migration Date: Mon, 15 Nov 2021 17:59:33 +0100 Message-Id: <20211115165315.135810649@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165313.549179499@linuxfoundation.org> References: <20211115165313.549179499@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dongli Zhang [ Upstream commit 042b2046d0f05cf8124c26ff65dbb6148a4404fb ] The tx queues are not stopped during the live migration. As a result, the ndo_start_xmit() may access netfront_info->queues which is freed by talk_to_netback()->xennet_destroy_queues(). This patch is to netif_device_detach() at the beginning of xen-netfront resuming, and netif_device_attach() at the end of resuming. CPU A CPU B talk_to_netback() -> if (info->queues) xennet_destroy_queues(info); to free netfront_info->queues xennet_start_xmit() to access netfront_info->queues -> err = xennet_create_queues(info, &num_queues); The idea is borrowed from virtio-net. Cc: Joe Jin Signed-off-by: Dongli Zhang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/xen-netfront.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 88280057e0321..7d389c2cc9026 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1439,6 +1439,10 @@ static int netfront_resume(struct xenbus_device *dev) dev_dbg(&dev->dev, "%s\n", dev->nodename); + netif_tx_lock_bh(info->netdev); + netif_device_detach(info->netdev); + netif_tx_unlock_bh(info->netdev); + xennet_disconnect_backend(info); return 0; } @@ -1987,6 +1991,10 @@ static int xennet_connect(struct net_device *dev) * domain a kick because we've probably just requeued some * packets. */ + netif_tx_lock_bh(np->netdev); + netif_device_attach(np->netdev); + netif_tx_unlock_bh(np->netdev); + netif_carrier_on(np->netdev); for (j = 0; j < num_queues; ++j) { queue = &np->queues[j]; -- 2.33.0