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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 D5CABC43331 for ; Sat, 7 Sep 2019 13:46:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4ADD21835 for ; Sat, 7 Sep 2019 13:46:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="CwMOtSxc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394643AbfIGNqy (ORCPT ); Sat, 7 Sep 2019 09:46:54 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:36491 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733278AbfIGNqy (ORCPT ); Sat, 7 Sep 2019 09:46:54 -0400 Received: by mail-pf1-f194.google.com with SMTP id y22so6417252pfr.3 for ; Sat, 07 Sep 2019 06:46:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=96pFkduzmJrdb3ENbrleY2Qc+hL1joupTUsDyzf+3Jg=; b=CwMOtSxczx2eMZCriVDekc1d3NEnKQdSLqodeqhfgy1eTZh0s64gUYMHLP7sR+h2pz PpMuUWucbND0muzS5EsRAr5KSOiU5CJYfrtrrHdI8j9c5fE3jH6Cs2AXyui5UhrmBYgo 5E/CCVknONawjItUGskD948PpGpdFbXUI35APW6Mx61Xvrygsv73vSEhD9IYveJZJ1ZF 4TZ6cSwNRNaVKt3PUQAMqeVgge04WGFOcyayxhM7+gzuTToFppM49PdrBkyP2Kj9PUkC ND4vMFMpV7GNZQcaARJjpAXm+2k6gJpWyLBUYLDk6R2JI3h3Jn8r8OqLYzRgZ9hmnRw2 JBKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=96pFkduzmJrdb3ENbrleY2Qc+hL1joupTUsDyzf+3Jg=; b=V2MZu3kXND0+JbWT9EjmJB7v4XsE67wvajYE/q9CLPWeiTIkh1IZBxtdY/2oNU1buw euK3eyovyzFKBL6QvLFI06nBm0Z/vjS6vz2aDoswjjaWwsusgSse5mP5MknzFx0rH/fv 0J3PQSJhNYR4uGzQGzWZRiZ4WZ+P0TTjdws9FcjrP30g1MwwlswrvXFn84kPGX+MkZcY SUzfGXZUY0gOMXElDNJjoKUBOvy0Ii2oVy5vBYeNl6DGpEL92bjac0fIVvmTSuaDskxo a4aNsQ/ihIxCkJJOaE2i8icv2PI2yogGUdVrFtMMtLrq3vzp5snaFtv1hCvOwgm5HDQd ob0g== X-Gm-Message-State: APjAAAUp/lT+BSRjBSfmPQwprqGCEAXOGC4sgLaQ0fVGIvMgPUQUteHS fiQfqpwQ+Tp+7ek10PdFAiA= X-Google-Smtp-Source: APXvYqwe3Lf+391JBdNfU+D4t9wcUGURPXbmUM/tY1v9z8vsepty6hZXJVRP4M2+q03ZJC1z+44e4g== X-Received: by 2002:a63:9e54:: with SMTP id r20mr13005565pgo.64.1567864013423; Sat, 07 Sep 2019 06:46:53 -0700 (PDT) Received: from ap-To-be-filled-by-O-E-M.8.8.8.8 ([14.33.120.60]) by smtp.gmail.com with ESMTPSA id d14sm14069210pfh.36.2019.09.07.06.46.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Sep 2019 06:46:52 -0700 (PDT) From: Taehee Yoo To: davem@davemloft.net, netdev@vger.kernel.org, j.vosburgh@gmail.com, vfalico@gmail.com, andy@greyhouse.net, jiri@resnulli.us, sd@queasysnail.net, roopa@cumulusnetworks.com, saeedm@mellanox.com, manishc@marvell.com, rahulv@marvell.com, kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, sashal@kernel.org, hare@suse.de, varun@chelsio.com, ubraun@linux.ibm.com, kgraul@linux.ibm.com, jay.vosburgh@canonical.com Cc: ap420073@gmail.com Subject: [PATCH net v2 06/11] macsec: use dynamic lockdep key instead of subclass Date: Sat, 7 Sep 2019 22:46:43 +0900 Message-Id: <20190907134643.32500-1-ap420073@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org All macsec device has same lockdep key and subclass is initialized with nest_level. But actual nest_level value can be changed when a lower device is attached. And at this moment, the subclass should be updated but it seems to be unsafe. So this patch makes macsec use dynamic lockdep key instead of the subclass. Test commands: ip link add bond0 type bond ip link add dummy0 type dummy ip link add macsec0 link bond0 type macsec ip link add macsec1 link dummy0 type macsec ip link set bond0 mtu 1000 ip link set macsec1 master bond0 ip link set bond0 up ip link set macsec0 up ip link set dummy0 up ip link set macsec1 up Splat looks like: [ 146.540123] ============================================ [ 146.540123] WARNING: possible recursive locking detected [ 146.540123] 5.3.0-rc7+ #322 Not tainted [ 146.540123] -------------------------------------------- [ 146.540123] ip/1340 is trying to acquire lock: [ 146.540123] 00000000446fd8bd (&macsec_netdev_addr_lock_key/1){+...}, at: dev_uc_sync_multiple+0xfa/0x1a0 [ 146.540123] [ 146.540123] but task is already holding lock: [ 146.540123] 00000000a9ab6378 (&macsec_netdev_addr_lock_key/1){+...}, at: dev_set_rx_mode+0x19/0x30 [ 146.540123] [ 146.540123] other info that might help us debug this: [ 146.540123] Possible unsafe locking scenario: [ 146.540123] [ 146.540123] CPU0 [ 146.540123] ---- [ 146.540123] lock(&macsec_netdev_addr_lock_key/1); [ 146.540123] lock(&macsec_netdev_addr_lock_key/1); [ 146.623155] [ 146.623155] *** DEADLOCK *** [ 146.623155] [ 146.623155] May be due to missing lock nesting notation [ 146.623155] [ 146.623155] 4 locks held by ip/1340: [ 146.623155] #0: 0000000026436ef0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0 [ 146.623155] #1: 00000000a9ab6378 (&macsec_netdev_addr_lock_key/1){+...}, at: dev_set_rx_mode+0x19/0x30 [ 146.623155] #2: 00000000a8947dd0 (&dev_addr_list_lock_key/3){+...}, at: dev_mc_sync+0xfa/0x1a0 [ 146.623155] #3: 00000000b62011e9 (rcu_read_lock){....}, at: bond_set_rx_mode+0x5/0x3c0 [bonding] [ 146.674970] [ 146.674970] stack backtrace: [ 146.687145] CPU: 0 PID: 1340 Comm: ip Not tainted 5.3.0-rc7+ #322 [ 146.693024] Call Trace: [ 146.693024] dump_stack+0x7c/0xbb [ 146.693024] __lock_acquire+0x26a9/0x3de0 [ 146.693024] ? register_lock_class+0x14d0/0x14d0 [ 146.693024] ? register_lock_class+0x14d0/0x14d0 [ 146.693024] lock_acquire+0x164/0x3b0 [ 146.693024] ? dev_uc_sync_multiple+0xfa/0x1a0 [ 146.693024] _raw_spin_lock_nested+0x2e/0x60 [ 146.693024] ? dev_uc_sync_multiple+0xfa/0x1a0 [ 146.693024] dev_uc_sync_multiple+0xfa/0x1a0 [ 146.693024] bond_set_rx_mode+0x269/0x3c0 [bonding] [ 146.751163] ? bond_init+0x6f0/0x6f0 [bonding] [ 146.757006] ? do_raw_spin_trylock+0xa9/0x170 [ 146.757006] dev_mc_sync+0x15a/0x1a0 [ 146.757006] macsec_dev_set_rx_mode+0x3a/0x50 [macsec] [ 146.757006] dev_set_rx_mode+0x21/0x30 [ 146.757006] __dev_open+0x202/0x310 [ 146.757006] ? dev_set_rx_mode+0x30/0x30 [ 146.757006] ? mark_held_locks+0xa5/0xe0 [ 146.757006] ? __local_bh_enable_ip+0xe9/0x1b0 [ 146.757006] __dev_change_flags+0x3c3/0x500 [ 146.757006] ? dev_set_allmulti+0x10/0x10 [ 146.757006] ? sched_clock_local+0xd4/0x140 [ 146.757006] ? check_chain_key+0x236/0x5d0 [ 146.757006] dev_change_flags+0x7a/0x160 [ 146.757006] do_setlink+0xa26/0x2f20 [ 146.757006] ? sched_clock_local+0xd4/0x140 [ ... ] Fixes: e20038724552 ("macsec: fix lockdep splats when nesting devices") Signed-off-by: Taehee Yoo --- v1 -> v2 : this patch isn't changed drivers/net/macsec.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 8f46aa1ddec0..25a4fc88145d 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -267,6 +267,8 @@ struct macsec_dev { struct pcpu_secy_stats __percpu *stats; struct list_head secys; struct gro_cells gro_cells; + struct lock_class_key xmit_lock_key; + struct lock_class_key addr_lock_key; unsigned int nest_level; }; @@ -2749,7 +2751,32 @@ static netdev_tx_t macsec_start_xmit(struct sk_buff *skb, #define MACSEC_FEATURES \ (NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST) -static struct lock_class_key macsec_netdev_addr_lock_key; + +static void macsec_dev_set_lockdep_one(struct net_device *dev, + struct netdev_queue *txq, + void *_unused) +{ + struct macsec_dev *macsec = macsec_priv(dev); + + lockdep_set_class(&txq->_xmit_lock, &macsec->xmit_lock_key); +} + +static struct lock_class_key qdisc_tx_busylock_key; +static struct lock_class_key qdisc_running_key; + +static void macsec_dev_set_lockdep_class(struct net_device *dev) +{ + struct macsec_dev *macsec = macsec_priv(dev); + + dev->qdisc_tx_busylock = &qdisc_tx_busylock_key; + dev->qdisc_running_key = &qdisc_running_key; + + lockdep_register_key(&macsec->addr_lock_key); + lockdep_set_class(&dev->addr_list_lock, &macsec->addr_lock_key); + + lockdep_register_key(&macsec->xmit_lock_key); + netdev_for_each_tx_queue(dev, macsec_dev_set_lockdep_one, NULL); +} static int macsec_dev_init(struct net_device *dev) { @@ -2780,6 +2807,7 @@ static int macsec_dev_init(struct net_device *dev) if (is_zero_ether_addr(dev->broadcast)) memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len); + macsec_dev_set_lockdep_class(dev); return 0; } @@ -2789,6 +2817,9 @@ static void macsec_dev_uninit(struct net_device *dev) gro_cells_destroy(&macsec->gro_cells); free_percpu(dev->tstats); + + lockdep_unregister_key(&macsec->addr_lock_key); + lockdep_unregister_key(&macsec->xmit_lock_key); } static netdev_features_t macsec_fix_features(struct net_device *dev, @@ -3263,10 +3294,6 @@ static int macsec_newlink(struct net *net, struct net_device *dev, dev_hold(real_dev); macsec->nest_level = dev_get_nest_level(real_dev) + 1; - netdev_lockdep_set_classes(dev); - lockdep_set_class_and_subclass(&dev->addr_list_lock, - &macsec_netdev_addr_lock_key, - macsec_get_nest_level(dev)); err = netdev_upper_dev_link(real_dev, dev, extack); if (err < 0) -- 2.17.1