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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 3D427C7618B for ; Fri, 26 Jul 2019 11:33:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 129A7216C8 for ; Fri, 26 Jul 2019 11:33:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726001AbfGZLdU (ORCPT ); Fri, 26 Jul 2019 07:33:20 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:42815 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725903AbfGZLdU (ORCPT ); Fri, 26 Jul 2019 07:33:20 -0400 X-Originating-IP: 86.250.200.211 Received: from windsurf (lfbn-1-17395-211.w86-250.abo.wanadoo.fr [86.250.200.211]) (Authenticated sender: thomas.petazzoni@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id ABC04240014; Fri, 26 Jul 2019 11:33:17 +0000 (UTC) Date: Fri, 26 Jul 2019 13:33:16 +0200 From: Thomas Petazzoni To: Greg Kroah-Hartman Cc: Sai Prakash Ranjan , Geert Uytterhoeven , Mathieu Poirier , Suzuki K Poulose , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Leo Yan , linux-arm-kernel@lists.infradead.org Subject: Re: [Regression] Missing device nodes for ETR, ETF and STM after CONFIG_UEVENT_HELPER=n Message-ID: <20190726133316.688a43d8@windsurf> In-Reply-To: <20190726101925.GA22476@kroah.com> References: <20190726070429.GA15714@kroah.com> <165028a7-ff12-dd28-cc4c-57a3961dbb40@codeaurora.org> <20190726084127.GA28470@kroah.com> <097942a1-6914-2542-450f-65a6147dc7aa@codeaurora.org> <6d48f996-6297-dc69-250b-790be6d2670c@codeaurora.org> <20190726101925.GA22476@kroah.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hello, On Fri, 26 Jul 2019 12:19:25 +0200 Greg Kroah-Hartman wrote: > > This somehow is not mounting etr, etf, stm devices when uevent-helper is > > disabled. Anyways as Suzuki mentioned, using devtmpfs does fix the issue. > > Last I looked (many years ago) mdev requires uevent-helper in order for > it to work. I recommend that if you rely on mdev to keep that option > enabled, or to just use devtmpfs and udev :) Since Busybox 1.31.0, mdev has gained a daemon mode. In this mode, mdev runs in the background, and receives uevent through a netlink socket. So there's been some changes in how Busybox mdev works in recent times. Best regards, Thomas -- Thomas Petazzoni, CTO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com