From nobody Tue Dec 23 23:48:28 2025 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8B28C26AC7; Tue, 30 Jan 2024 07:19:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706599144; cv=none; b=CW2TGJqn4b60KybrYk9kreSBbCcmiKzm7X21RBsDBKo+hMTM9o1PYCnHlYtD2ldC5i0Czl47mx1g9jl0d/77ePkoGWlyECG8RXHStD4xN5PbleF2y2JE2nmW5SnJ5mBPK074XV/49+njdpgkoeCssTBqoQ6TeA3xex8itldrQLc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706599144; c=relaxed/simple; bh=XD0iHpQFJ0q6NZTMOVuKJqYMVJwALyyXiYdp7IAr+OQ=; h=From:To:Cc:Subject:Date:Message-Id; b=hQXlMbQEChoLY84Tg18LET3MGbtY3PTT0n/ne/Kk2j3udNYC7oUwGP2TX+U2c2zxEGgunMmrYQCLo2YVmPg5CndjIrCNGQ6kFc4yKe9vQN4eFsOuvBv1RU0cTkrP5T/gYKjOYQd2HZz2wnVQrqhPLf7cCgtksW9kAnbiIvW7sOk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=Sn9C0PKK; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="Sn9C0PKK" Received: by linux.microsoft.com (Postfix, from userid 1134) id 8875920B2000; Mon, 29 Jan 2024 23:18:56 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 8875920B2000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1706599136; bh=KFdAJcXVrqcUHwnaCxf3QIvJzyS/dFmrIoKhQOSds9g=; h=From:To:Cc:Subject:Date:From; b=Sn9C0PKKkRuccV6/DavK5CClBZPt3JRklmnKX5xKKvK/bcQZR8Azy7qhwbwD97MfX bY5ssVZDmaWP5qnjwuVz+ccR/c9JQSTR12RMPj2nSxqLtmLVjsAMyIa1JSnLtYIsWh lscE9CqeBH3nMk4R8tXzoQ1Do+tNuDcCbCwxh6kk= From: Shradha Gupta To: "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Wojciech Drewek , linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Shradha Gupta , shradhagupta@microsoft.com, stable@vger.kernel.org Subject: [PATCH] hv_netvsc:Register VF in netvsc_probe if NET_DEVICE_REGISTER missed Date: Mon, 29 Jan 2024 23:18:55 -0800 Message-Id: <1706599135-12651-1-git-send-email-shradhagupta@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" If hv_netvsc driver is removed and reloaded, the NET_DEVICE_REGISTER handler cannot perform VF register successfully as the register call is received before netvsc_probe is finished. This is because we register register_netdevice_notifier() very early(even before vmbus_driver_register()). To fix this, we try to register each such matching VF( if it is visible as a netdevice) at the end of netvsc_probe. Cc: stable@vger.kernel.org Fixes: 85520856466e ("hv_netvsc: Fix race of register_netdevice_notifier an= d VF register") Suggested-by: Dexuan Cui Signed-off-by: Shradha Gupta Tested-on: Ubuntu22 Testcases: LISA testsuites verify_reload_hyperv_modules, perf_tcp_ntttcp_sriov --- drivers/net/hyperv/netvsc_drv.c | 49 ++++++++++++++++++++++++++++----- 1 file changed, 42 insertions(+), 7 deletions(-) diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_dr= v.c index 706ea5263e87..25c4dc9cc4bd 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -42,6 +42,10 @@ #define LINKCHANGE_INT (2 * HZ) #define VF_TAKEOVER_INT (HZ / 10) =20 +/* Macros to define the context of vf registration */ +#define VF_REG_IN_PROBE 1 +#define VF_REG_IN_RECV_CBACK 2 + static unsigned int ring_size __ro_after_init =3D 128; module_param(ring_size, uint, 0444); MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)"); @@ -2183,7 +2187,7 @@ static rx_handler_result_t netvsc_vf_handle_frame(str= uct sk_buff **pskb) } =20 static int netvsc_vf_join(struct net_device *vf_netdev, - struct net_device *ndev) + struct net_device *ndev, int context) { struct net_device_context *ndev_ctx =3D netdev_priv(ndev); int ret; @@ -2205,8 +2209,11 @@ static int netvsc_vf_join(struct net_device *vf_netd= ev, ndev->name, ret); goto upper_link_failed; } - - schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT); + /* If this registration is called from probe context vf_takeover + * is taken care of later in probe itself. + */ + if (context =3D=3D VF_REG_IN_RECV_CBACK) + schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT); =20 call_netdevice_notifiers(NETDEV_JOIN, vf_netdev); =20 @@ -2344,7 +2351,7 @@ static int netvsc_prepare_bonding(struct net_device *= vf_netdev) return NOTIFY_DONE; } =20 -static int netvsc_register_vf(struct net_device *vf_netdev) +static int netvsc_register_vf(struct net_device *vf_netdev, int context) { struct net_device_context *net_device_ctx; struct netvsc_device *netvsc_dev; @@ -2384,7 +2391,7 @@ static int netvsc_register_vf(struct net_device *vf_n= etdev) =20 netdev_info(ndev, "VF registering: %s\n", vf_netdev->name); =20 - if (netvsc_vf_join(vf_netdev, ndev) !=3D 0) + if (netvsc_vf_join(vf_netdev, ndev, context) !=3D 0) return NOTIFY_DONE; =20 dev_hold(vf_netdev); @@ -2485,7 +2492,7 @@ static int netvsc_unregister_vf(struct net_device *vf= _netdev) static int netvsc_probe(struct hv_device *dev, const struct hv_vmbus_device_id *dev_id) { - struct net_device *net =3D NULL; + struct net_device *net =3D NULL, *vf_netdev; struct net_device_context *net_device_ctx; struct netvsc_device_info *device_info =3D NULL; struct netvsc_device *nvdev; @@ -2597,6 +2604,34 @@ static int netvsc_probe(struct hv_device *dev, } =20 list_add(&net_device_ctx->list, &netvsc_dev_list); + + /* When the hv_netvsc driver is removed and readded, the + * NET_DEVICE_REGISTER for the vf device is replayed before probe + * is complete. This is because register_netdevice_notifier() gets + * registered before vmbus_driver_register() so that callback func + * is set before probe and we don't miss events like NETDEV_POST_INIT + * So, in this section we try to register each matching + * vf device that is present as a netdevice, knowing that it's register + * call is not processed in the netvsc_netdev_notifier(as probing is + * progress and get_netvsc_byslot fails). + */ + for_each_netdev(dev_net(net), vf_netdev) { + if (vf_netdev->netdev_ops =3D=3D &device_ops) + continue; + + if (vf_netdev->type !=3D ARPHRD_ETHER) + continue; + + if (is_vlan_dev(vf_netdev)) + continue; + + if (netif_is_bond_master(vf_netdev)) + continue; + + netvsc_prepare_bonding(vf_netdev); + netvsc_register_vf(vf_netdev, VF_REG_IN_PROBE); + __netvsc_vf_setup(net, vf_netdev); + } rtnl_unlock(); =20 netvsc_devinfo_put(device_info); @@ -2773,7 +2808,7 @@ static int netvsc_netdev_event(struct notifier_block = *this, case NETDEV_POST_INIT: return netvsc_prepare_bonding(event_dev); case NETDEV_REGISTER: - return netvsc_register_vf(event_dev); + return netvsc_register_vf(event_dev, VF_REG_IN_RECV_CBACK); case NETDEV_UNREGISTER: return netvsc_unregister_vf(event_dev); case NETDEV_UP: --=20 2.34.1