From nobody Mon Apr 20 07:30:14 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0534CCA473 for ; Tue, 21 Jun 2022 12:12:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349755AbiFUMMq (ORCPT ); Tue, 21 Jun 2022 08:12:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348842AbiFUMMi (ORCPT ); Tue, 21 Jun 2022 08:12:38 -0400 X-Greylist: delayed 1339 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 21 Jun 2022 05:12:36 PDT Received: from mx.kernkonzept.com (serv1.kernkonzept.com [159.69.200.6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D15E2BB07; Tue, 21 Jun 2022 05:12:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kernkonzept.com; s=mx1; h=Content-Transfer-Encoding:MIME-Version:Message-Id :Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=njJuoA2Sc/56TeF9U5fuCJ1Q1iYeeVXupfO3Z71rmfU=; b=N20iD1j4QJpCbcdtTtf0vx4SfS v9vaHEUavFbJcnwamVJjVHTPAgSNlSJXTH6poPimDs9+bULGexIuzt+l9cAjUpktSS0RCyKacIuCp 7mkrrtulA3TPEdxbQGC4sc5Fem19JxPiWAcf5N2zGRLSh38enkeRCc5KY2ypcoD+ovxYLed2+JLKv qD/IM8Xp/H194fGBE9LyVjxnqVy20zgwo5GUcbzjiUCR/QtX66QNX/o2nRLpjiZGWuqRSCMCEp5sY Qwl4QveMpiaAd3HMniNlZ1tVnv3oVi371F+FhewiOTracn0ddYLjmA3dk5eXCF63MrB9E/zqurcjw LYtHnsDA==; Received: from [10.22.3.24] (helo=kernkonzept.com) by mx.kernkonzept.com with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) id 1o3cOK-005hVa-SB; Tue, 21 Jun 2022 13:49:56 +0200 From: Stephan Gerhold To: "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend Cc: Stephan Gerhold , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH net] virtio_net: fix xdp_rxq_info bug after suspend/resume Date: Tue, 21 Jun 2022 13:48:44 +0200 Message-Id: <20220621114845.3650258-1-stephan.gerhold@kernkonzept.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The following sequence currently causes a driver bug warning when using virtio_net: # ip link set eth0 up # echo mem > /sys/power/state (or e.g. # rtcwake -s 10 -m mem) # ip link set eth0 down Missing register, driver bug WARNING: CPU: 0 PID: 375 at net/core/xdp.c:138 xdp_rxq_info_unreg+0x58/0x= 60 Call trace: xdp_rxq_info_unreg+0x58/0x60 virtnet_close+0x58/0xac __dev_close_many+0xac/0x140 __dev_change_flags+0xd8/0x210 dev_change_flags+0x24/0x64 do_setlink+0x230/0xdd0 ... This happens because virtnet_freeze() frees the receive_queue completely (including struct xdp_rxq_info) but does not call xdp_rxq_info_unreg(). Similarly, virtnet_restore() sets up the receive_queue again but does not call xdp_rxq_info_reg(). Actually, parts of virtnet_freeze_down() and virtnet_restore_up() are almost identical to virtnet_close() and virtnet_open(): only the calls to xdp_rxq_info_(un)reg() are missing. This means that we can fix this easily and avoid such problems in the future by just calling virtnet_close()/open() from the freeze/restore handlers. Aside from adding the missing xdp_rxq_info calls the only difference is that the refill work is only cancelled if netif_running(). However, this should not make any functional difference since the refill work should only be active if the network interface is actually up. Fixes: 754b8a21a96d ("virtio_net: setup xdp_rxq_info") Signed-off-by: Stephan Gerhold Acked-by: Jason Wang Acked-by: Jesper Dangaard Brouer --- drivers/net/virtio_net.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index db05b5e930be..969a67970e71 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2768,7 +2768,6 @@ static const struct ethtool_ops virtnet_ethtool_ops = =3D { static void virtnet_freeze_down(struct virtio_device *vdev) { struct virtnet_info *vi =3D vdev->priv; - int i; =20 /* Make sure no work handler is accessing the device */ flush_work(&vi->config_work); @@ -2776,14 +2775,8 @@ static void virtnet_freeze_down(struct virtio_device= *vdev) netif_tx_lock_bh(vi->dev); netif_device_detach(vi->dev); netif_tx_unlock_bh(vi->dev); - cancel_delayed_work_sync(&vi->refill); - - if (netif_running(vi->dev)) { - for (i =3D 0; i < vi->max_queue_pairs; i++) { - napi_disable(&vi->rq[i].napi); - virtnet_napi_tx_disable(&vi->sq[i].napi); - } - } + if (netif_running(vi->dev)) + virtnet_close(vi->dev); } =20 static int init_vqs(struct virtnet_info *vi); @@ -2791,7 +2784,7 @@ static int init_vqs(struct virtnet_info *vi); static int virtnet_restore_up(struct virtio_device *vdev) { struct virtnet_info *vi =3D vdev->priv; - int err, i; + int err; =20 err =3D init_vqs(vi); if (err) @@ -2800,15 +2793,9 @@ static int virtnet_restore_up(struct virtio_device *= vdev) virtio_device_ready(vdev); =20 if (netif_running(vi->dev)) { - for (i =3D 0; i < vi->curr_queue_pairs; i++) - if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL)) - schedule_delayed_work(&vi->refill, 0); - - for (i =3D 0; i < vi->max_queue_pairs; i++) { - virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); - virtnet_napi_tx_enable(vi, vi->sq[i].vq, - &vi->sq[i].napi); - } + err =3D virtnet_open(vi->dev); + if (err) + return err; } =20 netif_tx_lock_bh(vi->dev); --=20 2.30.2