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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 5B54CC433DB for ; Wed, 10 Mar 2021 16:47:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3685F64DE7 for ; Wed, 10 Mar 2021 16:47:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229790AbhCJQqt (ORCPT ); Wed, 10 Mar 2021 11:46:49 -0500 Received: from mga17.intel.com ([192.55.52.151]:29227 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232897AbhCJQqS (ORCPT ); Wed, 10 Mar 2021 11:46:18 -0500 IronPort-SDR: F5UdMpwQ9TCtVCxNersPagI+L7vJ5v0TLbtE7U2oWhv+fYCLaune76kUgwEHtIIDBsFXKgWFgG 8ahFnUos3IxQ== X-IronPort-AV: E=McAfee;i="6000,8403,9919"; a="168426360" X-IronPort-AV: E=Sophos;i="5.81,237,1610438400"; d="scan'208";a="168426360" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2021 08:46:17 -0800 IronPort-SDR: Sds4hKTkWchtDN71VgM2MRAuXkwKsgw53XHFCjqIMXLUsOznZPp210pmlL9nNNqrYIl0n5uO3/ 7drXJ3gJVLng== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,237,1610438400"; d="scan'208";a="603163275" Received: from linux.intel.com ([10.54.29.200]) by fmsmga005.fm.intel.com with ESMTP; 10 Mar 2021 08:46:17 -0800 Received: from [10.249.151.8] (mtkaczyk-MOBL1.ger.corp.intel.com [10.249.151.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id EEB9F580816; Wed, 10 Mar 2021 08:46:15 -0800 (PST) Subject: Re: [PATCH] mdmonitor: check if udev has finished events processing To: Jes Sorensen , Michael Fritscher , Wols Lists , Oleksandr Shchirskyi Cc: linux-raid@vger.kernel.org, artur.paszkiewicz@intel.com References: <20210114141416.42934-1-oleksandr.shchirskyi@intel.com> <51ec46c1-c632-b3a9-010f-8f13aee0e02c@linux.intel.com> <60473C1F.4080602@youngman.org.uk> <1b5b0495-c645-7f81-24f4-07fbad54ca0e@fritscher.net> <6c833d95-7610-a3c3-01ca-3167a3e80335@trained-monkey.org> From: "Tkaczyk, Mariusz" Message-ID: <4c6c4262-7590-df44-e8cb-eca6bc936287@linux.intel.com> Date: Wed, 10 Mar 2021 17:46:13 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <6c833d95-7610-a3c3-01ca-3167a3e80335@trained-monkey.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On 09.03.2021 15:52, Jes Sorensen wrote: > On 3/9/21 6:17 AM, Tkaczyk, Mariusz wrote: >> On 09.03.2021 10:45, Michael Fritscher wrote: >>> Am 09.03.21 um 10:13 schrieb Wols Lists: >>>> Is udev part of systemd? Are there alternate implementations for the >>>> anti-systemd-holdouts? Iirc you don't need systemd itself to have udev, >>>> but it might provoke a few screams ... >>>> >>>> My current (gentoo) system is OpenRC, but that's still on KDE4 and >>>> hasn't been updated in a couple of years (don't ask why). My new system >>>> is currently being built and is gentoo/systemd, but it's clear the >>>> anti-systemd sentiment is still strong ... >>>> >>>> Cheers, >>>> Wol >>>> >>> >>> Good day, >>> >>> there is e.g. eudev ( https://wiki.gentoo.org/wiki/Project:Eudev ) with >>> the explicit target to be used without systemd. >> >> It is a udev replacement and offers similar functionality. >> I'm wondering on configuration without udev (systemd or other forks). >> Is it still a case? > > This is my main concern, small embedded devices that don't use systemd. > I've never been a big systemd fan, but it's how the chips have fallen, > so I am not overly worried about a couple of fanatics. > > If eudev can do the trick, that would be great. > > Cheers, > Jes > Hello, Mdadm is in use in openwrt without udev (thanks to Artur for research). They are using hotplug scripts: https://openwrt.org/docs/guide-user/base-system/hotplug#coldplug To provide compatibility with libudev dependency they wrote small shim: https://openwrt.org/packages/pkgdata/libudev-fbsd Unfortunately, not all libudev functions are defined, mdadm compilation there might be problematic: https://openwrt.org/packages/pkgdata_lede17_1/mdadm Now, it makes sense to define libudev as optional dependency. It should be done before new release, Intel will do that. Anyway, I still think that we should drop udev detection from mdadm. I there is no systemd-udevd, we should expect other tool to provide similar functionality, like hotplug scripts, eudev. IMO mdadm doesn't need to create any link. Mariusz