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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 4D6E2C04EB9 for ; Wed, 5 Dec 2018 19:40:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0B211214E0 for ; Wed, 5 Dec 2018 19:40:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0B211214E0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728326AbeLETk5 (ORCPT ); Wed, 5 Dec 2018 14:40:57 -0500 Received: from mga18.intel.com ([134.134.136.126]:19844 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727523AbeLETk5 (ORCPT ); Wed, 5 Dec 2018 14:40:57 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Dec 2018 11:40:56 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,319,1539673200"; d="scan'208";a="98359884" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by orsmga006.jf.intel.com with SMTP; 05 Dec 2018 11:40:52 -0800 Received: by stinkbox (sSMTP sendmail emulation); Wed, 05 Dec 2018 21:40:51 +0200 Date: Wed, 5 Dec 2018 21:40:51 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Greg Kroah-Hartman Cc: linux-bluetooth@vger.kernel.org, Dmitry Torokhov , Marcel Holtmann , Kay Sievers , Zbigniew =?utf-8?Q?J=C4=99drzejewski-Szmek?= , systemd-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 BlueZ] hid2hci: Fix udev rules for linux-4.14+ Message-ID: <20181205194051.GU9144@intel.com> References: <20180620164240.6535-1-ville.syrjala@linux.intel.com> <20181204204117.14964-1-ville.syrjala@linux.intel.com> <20181205070621.GE16346@kroah.com> <20181205154032.GT9144@intel.com> <20181205192036.GB434@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181205192036.GB434@kroah.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 05, 2018 at 08:20:36PM +0100, Greg Kroah-Hartman wrote: > On Wed, Dec 05, 2018 at 05:40:32PM +0200, Ville Syrjälä wrote: > > On Wed, Dec 05, 2018 at 08:06:21AM +0100, Greg Kroah-Hartman wrote: > > > On Tue, Dec 04, 2018 at 10:41:17PM +0200, Ville Syrjala wrote: > > > > From: Ville Syrjälä > > > > > > > > Since commit 1455cf8dbfd0 ("driver core: emit uevents when > > > > device is bound to a driver") the kernel started emitting > > > > "bind" and "unbind" uevents which confuse the hid2hci > > > > udev rules. > > > > > > > > The symptoms on an affected machine (Dell E5400 in my case) > > > > include bluetooth devices not appearing and udev hogging > > > > the cpu as it's busy processing a constant stream of these > > > > "bind"+"unbind" uevents. > > > > > > What is causing a "stream" of bind and unbind events? This only happens > > > when a device is attached to a driver or removed from a driver, which is > > > caused by something else happening. > > > > Not sure if it's just due to this thing causing devices to > > appear/disappear during bind/unbind events or what. > > Someone has to be telling the kernel to bind/unbind from a driver to > a device, it doesn't do it on its own. Look at your other rules/scripts > for that. > > Also note that the kernel has been doing this for over a year now (since > 4.l4), what just happened in 4.19 to cause this to be an issue? It became an issue for me after I got a machine that suffers from this. The regression has been present ever since commit 1455cf8dbfd0 ("driver core: emit uevents when device is bound to a driver"). You need a Dell E5400 or something similar to see it since those have these magic bluetooth devices or whatever. > > > > This should not be a normal > > > occurance, unless something odd is happening to your hardware? > > > > It's not specific to my hardware. Lot's of people are affected. > > See eg. > > https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1759836 > > > > Acutally looking through that bug it seems someone else noticed > > hid2hci failing lot in the logs. So maybe it's just that we already > > switched the mode during "add", and then we try to redo the same > > thing during "bind" which fails, and that then causes and unbind? > > You have to manually unbind the device, the kernel does not do that. So > perhaps you have a broken udev rule somewhere else that would do > something odd like unbind/bind? > > I don't see this happening on my systems, but hey, I know better than to > run Ubuntu :) As do I. And you don't see it because you don't have the right hardware. -- Ville Syrjälä Intel