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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 AA676C33CB3 for ; Tue, 28 Jan 2020 04:43:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79F032173E for ; Tue, 28 Jan 2020 04:43:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="RDbsI95f" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726599AbgA1Enf (ORCPT ); Mon, 27 Jan 2020 23:43:35 -0500 Received: from mail-pf1-f173.google.com ([209.85.210.173]:44922 "EHLO mail-pf1-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726080AbgA1Enf (ORCPT ); Mon, 27 Jan 2020 23:43:35 -0500 Received: by mail-pf1-f173.google.com with SMTP id y5so2911275pfb.11 for ; Mon, 27 Jan 2020 20:43:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=o/eiodGD5lp4RWZNR205Jfk41Ea2mOrlpEOAJGFIIOE=; b=RDbsI95fxayjdpnQGgTzzWcOn+WF5GX4k/uSyZQlGLHI+1rbOZT/V0Go2Bfaaq/LXi +GTw9RApTN5AaG+yvm+3S7bxl1mEWmLqecwTtD/Pr/MiRZ5jueoHu351RXFAGSdnUpE+ M5CHud/zIRiBVrqG2IQcdWM2IypgB52/sJgKA1D3lv1sQQ2L83IUz0eT/IdnwMOX5doh yrd5RBaYVxQe6BtZvJetc96h167zt+dQpuOreo+vr0tvVLzOlUcgAElvJsOz1IlUeSFI fSkvu+z1LyVLIuHoXF4Y/9bMA8P7+dmC1zERot7GkrKYBcG5O3YqMYytWzXAD48AxCxc eURg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=o/eiodGD5lp4RWZNR205Jfk41Ea2mOrlpEOAJGFIIOE=; b=Uot6eRdWuzXhWb/fZ+q1YU5g92snU6H921IKET44fOLylvQC7xNzHWI1d16tsAqibh 7B0AVszH4JJ41ViN9WNHTd2JsPRJg5H/miwBybnx32jH+jK73WqW3IOPsOHXVIc5gLtM 7DOswkhxLmUJIpiDZyjC0Fi+IDxsUNmb662Zt7UxLX1ppj2d0AIWpe+fNPNiixTuKJux Y8YfIcuyF5yzjUERDaDqPvT9uJDNvs/LV+mBUPAD026Cbg11cTk2ZeMWHe94jEpRaIXe ZDyvYdEHkWh8GfuDSgXkJLkReprQu6ubUExYOHMFdCfQqUkBTw5gnBZnpX102qWUQPsA 5d+A== X-Gm-Message-State: APjAAAWOFbnlb2FyeBDKaJ0SxD1TZEreLfthFzLl30t5npxL0sbZW6TE bHz0zS+2NvaIJiwndM6JADk= X-Google-Smtp-Source: APXvYqwxDJIVmbpnATu5bEpg3pxqqVwS4f7Pl082BK6VxiT99QH6kMl4MJUW5za+f9V+ZY+s5MRTDQ== X-Received: by 2002:a63:ff20:: with SMTP id k32mr22273186pgi.448.1580186614618; Mon, 27 Jan 2020 20:43:34 -0800 (PST) Received: from localhost ([2401:fa00:8f:203:5bbb:c872:f2b1:f53b]) by smtp.gmail.com with ESMTPSA id z14sm17352926pgj.43.2020.01.27.20.43.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2020 20:43:33 -0800 (PST) Date: Tue, 28 Jan 2020 13:43:32 +0900 From: Sergey Senozhatsky To: Andy Shevchenko Cc: Petr Mladek , Sergey Senozhatsky , Steven Rostedt , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 4/5] console: Avoid positive return code from unregister_console() Message-ID: <20200128044332.GA115889@google.com> References: <20200127114719.69114-1-andriy.shevchenko@linux.intel.com> <20200127114719.69114-4-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200127114719.69114-4-andriy.shevchenko@linux.intel.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 (20/01/27 13:47), Andy Shevchenko wrote: [..] > res = _braille_unregister_console(console); > - if (res) > + if (res < 0) > return res; > + if (res > 0) > + return 0; > > - res = 1; > + res = -ENODEV; > console_lock(); > if (console_drivers == console) { > console_drivers=console->next; > @@ -2838,6 +2840,9 @@ int unregister_console(struct console *console) > if (!res && (console->flags & CON_EXTENDED)) > nr_ext_console_drivers--; > > + if (res && !(console->flags & CON_ENABLED)) > + res = 0; Console is not on the console_drivers list. Why does !ENABLED case require extra handling? What about the case when console is ENABLED but still not registered? I think that if the console is not on the list (was never registered) then we can just bail out, without console_sysfs_notify(), etc. IOW, if (res) { console->flags &= ~CON_ENABLED; /* just in case */ console_unlock(); return res; } -ss