From patchwork Fri Feb 4 09:22:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 540336 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 B9E62C433EF for ; Fri, 4 Feb 2022 09:24:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357361AbiBDJY1 (ORCPT ); Fri, 4 Feb 2022 04:24:27 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:42790 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357680AbiBDJXg (ORCPT ); Fri, 4 Feb 2022 04:23:36 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4179461601; Fri, 4 Feb 2022 09:23:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22F37C004E1; Fri, 4 Feb 2022 09:23:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643966615; bh=i1By24VIoY2lC/wDQNa/L9E+AUs3H7fv9iax0aywOIY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kxzNd352DGLyFAt5ui79/EHukOfVQLy4ZKj8KHSzKU/IEhUP9NPiSUKF00cUTA+LB Y58P7qU7ekiOPD8GPZs6isanxr4cC8LHwFCRPiqJ/ceZ63BNGpHXZUVLdWUP09Wr3E Yzx6nYCsoKAVGiTFpm5WvIUJOAQ+HUQFe3xVbH7Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Roi Dayan , Vlad Buslov , Saeed Mahameed Subject: [PATCH 5.15 19/32] net/mlx5: Bridge, Fix devlink deadlock on net namespace deletion Date: Fri, 4 Feb 2022 10:22:29 +0100 Message-Id: <20220204091915.888414403@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220204091915.247906930@linuxfoundation.org> References: <20220204091915.247906930@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Roi Dayan commit 880b517691908fb753019b9b27cd082e7617debd upstream. When changing mode to switchdev, rep bridge init registered to netdevice notifier holds the devlink lock and then takes pernet_ops_rwsem. At that time deleting a netns holds pernet_ops_rwsem and then takes the devlink lock. Example sequence is: $ ip netns add foo $ devlink dev eswitch set pci/0000:00:08.0 mode switchdev & $ ip netns del foo deleting netns trace: [ 1185.365555] ? devlink_pernet_pre_exit+0x74/0x1c0 [ 1185.368331] ? mutex_lock_io_nested+0x13f0/0x13f0 [ 1185.370984] ? xt_find_table+0x40/0x100 [ 1185.373244] ? __mutex_lock+0x24a/0x15a0 [ 1185.375494] ? net_generic+0xa0/0x1c0 [ 1185.376844] ? wait_for_completion_io+0x280/0x280 [ 1185.377767] ? devlink_pernet_pre_exit+0x74/0x1c0 [ 1185.378686] devlink_pernet_pre_exit+0x74/0x1c0 [ 1185.379579] ? devlink_nl_cmd_get_dumpit+0x3a0/0x3a0 [ 1185.380557] ? xt_find_table+0xda/0x100 [ 1185.381367] cleanup_net+0x372/0x8e0 changing mode to switchdev trace: [ 1185.411267] down_write+0x13a/0x150 [ 1185.412029] ? down_write_killable+0x180/0x180 [ 1185.413005] register_netdevice_notifier+0x1e/0x210 [ 1185.414000] mlx5e_rep_bridge_init+0x181/0x360 [mlx5_core] [ 1185.415243] mlx5e_uplink_rep_enable+0x269/0x480 [mlx5_core] [ 1185.416464] ? mlx5e_uplink_rep_disable+0x210/0x210 [mlx5_core] [ 1185.417749] mlx5e_attach_netdev+0x232/0x400 [mlx5_core] [ 1185.418906] mlx5e_netdev_attach_profile+0x15b/0x1e0 [mlx5_core] [ 1185.420172] mlx5e_netdev_change_profile+0x15a/0x1d0 [mlx5_core] [ 1185.421459] mlx5e_vport_rep_load+0x557/0x780 [mlx5_core] [ 1185.422624] ? mlx5e_stats_grp_vport_rep_num_stats+0x10/0x10 [mlx5_core] [ 1185.424006] mlx5_esw_offloads_rep_load+0xdb/0x190 [mlx5_core] [ 1185.425277] esw_offloads_enable+0xd74/0x14a0 [mlx5_core] Fix this by registering rep bridges for per net netdev notifier instead of global one, which operats on the net namespace without holding the pernet_ops_rwsem. Fixes: 19e9bfa044f3 ("net/mlx5: Bridge, add offload infrastructure") Signed-off-by: Roi Dayan Reviewed-by: Vlad Buslov Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx5/core/en/rep/bridge.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/bridge.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/bridge.c @@ -491,7 +491,7 @@ void mlx5e_rep_bridge_init(struct mlx5e_ } br_offloads->netdev_nb.notifier_call = mlx5_esw_bridge_switchdev_port_event; - err = register_netdevice_notifier(&br_offloads->netdev_nb); + err = register_netdevice_notifier_net(&init_net, &br_offloads->netdev_nb); if (err) { esw_warn(mdev, "Failed to register bridge offloads netdevice notifier (err=%d)\n", err); @@ -526,7 +526,7 @@ void mlx5e_rep_bridge_cleanup(struct mlx return; cancel_delayed_work_sync(&br_offloads->update_work); - unregister_netdevice_notifier(&br_offloads->netdev_nb); + unregister_netdevice_notifier_net(&init_net, &br_offloads->netdev_nb); unregister_switchdev_blocking_notifier(&br_offloads->nb_blk); unregister_switchdev_notifier(&br_offloads->nb); destroy_workqueue(br_offloads->wq);