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=-2.3 required=3.0 tests=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 D9990C2D0C3 for ; Tue, 31 Dec 2019 02:40:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF500206DB for ; Tue, 31 Dec 2019 02:40:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726709AbfLaCk6 (ORCPT ); Mon, 30 Dec 2019 21:40:58 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:55612 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725536AbfLaCk6 (ORCPT ); Mon, 30 Dec 2019 21:40:58 -0500 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1im7So-0001le-HG; Tue, 31 Dec 2019 02:40:54 +0000 Date: Tue, 31 Dec 2019 02:40:54 +0000 From: Al Viro To: Rob Landley Cc: Randy Dunlap , linux-kernel@vger.kernel.org Subject: Re: Why is CONFIG_VT forced on? Message-ID: <20191231024054.GC4203@ZenIV.linux.org.uk> References: <9b79fb95-f20c-f299-f568-0ffb60305f04@landley.net> <018540ef-0327-78dc-ea5c-a43318f1f640@landley.net> <774dfe49-61a0-0144-42b7-c2cbac150687@landley.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <774dfe49-61a0-0144-42b7-c2cbac150687@landley.net> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 30, 2019 at 08:04:35PM -0600, Rob Landley wrote: > > > On 12/30/19 7:45 PM, Rob Landley wrote: > > On 12/30/19 6:59 PM, Randy Dunlap wrote: > >> # > >> # Character devices > >> # > >> CONFIG_TTY=y > >> # CONFIG_VT is not set > >> > >> But first you must set/enable EXPERT. See the bool prompt. > > > > Wait, the if doesn't _disable_ the symbol? It disables _editability_ of the > > symbol, but the symbol can still be on (and displayed) when the if is false? > > (Why would...) > > > > Ok. Thanks for pointing that out. Any idea why the menuconfig help text has no > > mention of this? > > So if I disable CONFIG_EXPERT, using miniconfig I then need to manually switch on: > > ./init/Kconfig: bool "Namespaces support" if EXPERT > ./init/Kconfig: bool "Multiple users, groups and capabilities support" if EXPERT > ./init/Kconfig: bool "Sysfs syscall support" if EXPERT > ./init/Kconfig: bool "open by fhandle syscalls" if EXPERT > ./init/Kconfig: bool "Posix Clocks & timers" if EXPERT > ./init/Kconfig: bool "Enable support for printk" if EXPERT > ./init/Kconfig: bool "BUG() support" if EXPERT > ./init/Kconfig: bool "Enable ELF core dumps" if EXPERT > ./init/Kconfig: bool "Enable full-sized data structures for core" if EXPERT > ./init/Kconfig: bool "Enable futex support" if EXPERT > ./init/Kconfig: bool "Enable eventpoll support" if EXPERT > ./init/Kconfig: bool "Enable signalfd() system call" if EXPERT > ./init/Kconfig: bool "Enable timerfd() system call" if EXPERT > ./init/Kconfig: bool "Enable eventfd() system call" if EXPERT > ./init/Kconfig: bool "Use full shmem filesystem" if EXPERT > ./init/Kconfig: bool "Enable AIO support" if EXPERT > ./init/Kconfig: bool "Enable IO uring support" if EXPERT > ./init/Kconfig: bool "Enable madvise/fadvise syscalls" if EXPERT > ./init/Kconfig: bool "Enable membarrier() system call" if EXPERT > ./init/Kconfig: bool "Load all symbols for debugging/ksymoops" if EXPERT > ./init/Kconfig: bool "Enable rseq() system call" if EXPERT > ./init/Kconfig: bool "Enabled debugging of rseq() system call" if EXPERT > ./init/Kconfig: bool "PC/104 support" if EXPERT > ./init/Kconfig: bool "Enable VM event counters for /proc/vmstat" if EXPERT No. What you need is * actually attempt to flip CONFIG_EXPERT (go to "General setup" submenu and set "Configure standard kernel features (expert users)" there) * check the resulting .config (or look at the items in question via menuconfig) * get enlightened Rob, if you are in a mood for a long wank, it's your business. But try to avoid spraying the results over public lists.