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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 1D452C47404 for ; Thu, 12 Sep 2019 11:54:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2D6A20856 for ; Thu, 12 Sep 2019 11:54:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fmejUcQp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731351AbfILLyd (ORCPT ); Thu, 12 Sep 2019 07:54:33 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:37060 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730923AbfILLyc (ORCPT ); Thu, 12 Sep 2019 07:54:32 -0400 Received: by mail-lj1-f194.google.com with SMTP id y5so12487304lji.4 for ; Thu, 12 Sep 2019 04:54:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Vj0SR+yzDIZpsuoRQslUYdAjMnyWuXc5vlr+ljKbMWU=; b=fmejUcQpGOOhu1yXz7XvwtipwgqumIj9D8OGvChNKN+y9mXI+gwrqF8E0SfE8Op4sS 0xVEsbkdVdolyNdHzm6SptgMdKSG9Aqsp8uARdQtLNL0Ndi9vr6RVVYvbC0O5h7A15EU p8M54Y4Gdbh2MIx9vuwv06jZJzNAZZzF1hyUOs3tb3cDyzup2W9JqBZlBfHKGsJSdstL Ix1IDfFjYf7oI3ebWu6NArCNrf9EK/1Vefxb1JlhkHhoJFKz3XnmqAIFj5de2EzIWVRH W2DZKH8ejj9hcE+e2P5A9NNlc2qQqwQglAPJcTfwKO4Lrk13gf14VaXrVYOTb3e5HgzQ FRxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Vj0SR+yzDIZpsuoRQslUYdAjMnyWuXc5vlr+ljKbMWU=; b=Ytc2tqcozAG2QHk4fs+Yl6QLSxZFUhYiirYPIZqq7PGe6rkXIhCqytWuAzOC8f7DW+ kum2VN4C3B/GI7y6bHJfBVGyIg0PD4FPYHDbHu+cWy1YgGZ5rIcM7stLzUeOcm4umY7p UaN2gnGVLiEUsoIJY14Hx0dKzJYBeOoNUwnEffHcugi04U8tuBl70OOV0Zzl3R/4vMYn OpB7Fb5qL5MeXcEauj5wCbdLscTY+U5v9y6Y7U+AcuemeSqhJu79eTZbFgAw8tHzUgPi g0Kve88TuFnHokdjkF08G9RH+V/1FIX4/hm+rWSJryH4BlFTCaNvxv523UJXcBOjNbBn JfOQ== X-Gm-Message-State: APjAAAX/2pJYnG49+mG3Hx6NksWQQblAHINdkUHlHpjxDitUEq0l0fdH RjUeNAPaSp4t2CWljF5jD1zXm5SvQ0flj1AysCM= X-Google-Smtp-Source: APXvYqxeaeWhKT6vNuTKX5/soTx/nSLjq4jLtpUicAFrQzga/3r0y15qBSgKneJ6mhD4PriApxxLQi+S/3JeHHE7myI= X-Received: by 2002:a2e:9d88:: with SMTP id c8mr11449093ljj.157.1568289270610; Thu, 12 Sep 2019 04:54:30 -0700 (PDT) MIME-Version: 1.0 References: <20190912.113807.52193745382103083.davem@davemloft.net> <20190912.133717.257813019167130934.davem@davemloft.net> In-Reply-To: <20190912.133717.257813019167130934.davem@davemloft.net> From: Taehee Yoo Date: Thu, 12 Sep 2019 20:54:19 +0900 Message-ID: Subject: Re: [PATCH net v2 01/11] net: core: limit nested device depth To: David Miller Cc: Netdev , j.vosburgh@gmail.com, vfalico@gmail.com, Andy Gospodarek , =?UTF-8?B?SmnFmcOtIFDDrXJrbw==?= , sd@queasysnail.net, Roopa Prabhu , 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 Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 12 Sep 2019 at 20:37, David Miller wrote: > > From: Taehee Yoo > Date: Thu, 12 Sep 2019 19:14:37 +0900 > > > On Thu, 12 Sep 2019 at 18:38, David Miller wrote: > >> > >> From: Taehee Yoo > >> Date: Thu, 12 Sep 2019 12:56:19 +0900 > >> > >> > I tested with this reproducer commands without lockdep. > >> > > >> > ip link add dummy0 type dummy > >> > ip link add link dummy0 name vlan1 type vlan id 1 > >> > ip link set vlan1 up > >> > > >> > for i in {2..200} > >> > do > >> > let A=$i-1 > >> > > >> > ip link add name vlan$i link vlan$A type vlan id $i > >> > done > >> > ip link del vlan1 <-- this command is added. > >> > >> Is there any other device type which allows arbitrary nesting depth > >> in this manner other than VLAN? Perhaps it is the VLAN nesting > >> depth that we should limit instead of all of this extra code. > > > > Below device types have the same problem. > > VLAN, BONDING, TEAM, VXLAN, MACVLAN, and MACSEC. > > All the below test commands reproduce a panic. > > I think then we need to move the traversals over to a iterative > rather than recursive algorithm. I agree with that. So I will check it out then send a v3 patchset. Thank you!