Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756744AbcDNQlB (ORCPT ); Thu, 14 Apr 2016 12:41:01 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:34055 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753314AbcDNQk7 (ORCPT ); Thu, 14 Apr 2016 12:40:59 -0400 Message-ID: <1460652056.10638.50.camel@edumazet-glaptop3.roam.corp.google.com> Subject: Re: Deleting child qdisc doesn't reset parent to default qdisc? From: Eric Dumazet To: Phil Sutter Cc: Jiri Kosina , Jamal Hadi Salim , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 14 Apr 2016 09:40:56 -0700 In-Reply-To: <20160414162229.GF3715@orbyte.nwl.cc> References: <1460646099.10638.44.camel@edumazet-glaptop3.roam.corp.google.com> <20160414151813.GE3715@orbyte.nwl.cc> <1460648680.10638.47.camel@edumazet-glaptop3.roam.corp.google.com> <20160414162229.GF3715@orbyte.nwl.cc> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 848 Lines: 23 On Thu, 2016-04-14 at 18:22 +0200, Phil Sutter wrote: > And those being invisible can be overridden using 'tc qd add', right? > AFAIR they're not listed because they don't properly register, so the > system doesn't care to override them. In this case we could change all > classful qdiscs to restore the default qdisc if a leaf qdisc is being > deleted instead of noop (which is probably not what the user wants > anyway). Even if they properly register, they are not visible. Take a look at https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=95dc19299f741c986227ec33e23cbf9b3321f812 for some context. When a default pfifo is created on say a HTB class, you do not see it by default in a dump. If you have 100 HTB classes, HTB created 100 pfifo just fine, and it works, unless an admin tries to delete them maybe ;)