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=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 54D8FC48BDF for ; Tue, 15 Jun 2021 04:56:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33D8B61410 for ; Tue, 15 Jun 2021 04:56:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229919AbhFOE6W (ORCPT ); Tue, 15 Jun 2021 00:58:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:48348 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229463AbhFOE6V (ORCPT ); Tue, 15 Jun 2021 00:58:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 188AC613DA; Tue, 15 Jun 2021 04:56:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623732977; bh=NRGdtYDLvpCd+/uSyt1rDy8DtVDlYObyw/BBM2ESELg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mLnV0J1JV2NotD7G0fMaeniEAsvdI/ryPu6oPWnXY2U3InxqVUGCzWWJkd4NBmOSE 2HR/FqST6AgnTIQxs/4s9cneWaaIcqzo6w8d2oZdJbgtqPQyx8TJTkQY3K058Pn4Fx AngERUkdeTtZ1abv0L4JQVVWtv/edwywvFqeZe3c= Date: Tue, 15 Jun 2021 06:56:13 +0200 From: Greg KH To: Siddharth Gupta Cc: bjorn.andersson@linaro.org, ohad@wizery.com, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, psodagud@codeaurora.org, stable@vger.kernel.org Subject: Re: [PATCH v3 1/4] remoteproc: core: Move cdev add before device add Message-ID: References: <1623723671-5517-1-git-send-email-sidgup@codeaurora.org> <1623723671-5517-2-git-send-email-sidgup@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1623723671-5517-2-git-send-email-sidgup@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org On Mon, Jun 14, 2021 at 07:21:08PM -0700, Siddharth Gupta wrote: > When cdev_add is called after device_add has been called there is no > way for the userspace to know about the addition of a cdev as cdev_add > itself doesn't trigger a uevent notification, or for the kernel to > know about the change to devt. This results in two problems: > - mknod is never called for the cdev and hence no cdev appears on > devtmpfs. > - sysfs links to the new cdev are not established. > > The cdev needs to be added and devt assigned before device_add() is > called in order for the relevant sysfs and devtmpfs entries to be > created and the uevent to be properly populated. So this means no one ever ran this code on a system that used devtmpfs? How was it ever tested? 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Tue, 15 Jun 2021 04:56:20 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 188AC613DA; Tue, 15 Jun 2021 04:56:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623732977; bh=NRGdtYDLvpCd+/uSyt1rDy8DtVDlYObyw/BBM2ESELg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mLnV0J1JV2NotD7G0fMaeniEAsvdI/ryPu6oPWnXY2U3InxqVUGCzWWJkd4NBmOSE 2HR/FqST6AgnTIQxs/4s9cneWaaIcqzo6w8d2oZdJbgtqPQyx8TJTkQY3K058Pn4Fx AngERUkdeTtZ1abv0L4JQVVWtv/edwywvFqeZe3c= Date: Tue, 15 Jun 2021 06:56:13 +0200 From: Greg KH To: Siddharth Gupta Cc: bjorn.andersson@linaro.org, ohad@wizery.com, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, psodagud@codeaurora.org, stable@vger.kernel.org Subject: Re: [PATCH v3 1/4] remoteproc: core: Move cdev add before device add Message-ID: References: <1623723671-5517-1-git-send-email-sidgup@codeaurora.org> <1623723671-5517-2-git-send-email-sidgup@codeaurora.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1623723671-5517-2-git-send-email-sidgup@codeaurora.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210615_055619_188178_6717D7D4 X-CRM114-Status: GOOD ( 14.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jun 14, 2021 at 07:21:08PM -0700, Siddharth Gupta wrote: > When cdev_add is called after device_add has been called there is no > way for the userspace to know about the addition of a cdev as cdev_add > itself doesn't trigger a uevent notification, or for the kernel to > know about the change to devt. This results in two problems: > - mknod is never called for the cdev and hence no cdev appears on > devtmpfs. > - sysfs links to the new cdev are not established. > > The cdev needs to be added and devt assigned before device_add() is > called in order for the relevant sysfs and devtmpfs entries to be > created and the uevent to be properly populated. So this means no one ever ran this code on a system that used devtmpfs? How was it ever tested? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel