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_INVALID,DKIM_SIGNED, 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 177CFC2D0C3 for ; Tue, 31 Dec 2019 02:03:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D776E2071E for ; Tue, 31 Dec 2019 02:03:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qRWm/zNl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726635AbfLaCD2 (ORCPT ); Mon, 30 Dec 2019 21:03:28 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:41666 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725379AbfLaCD2 (ORCPT ); Mon, 30 Dec 2019 21:03:28 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:To: Subject:Sender:Reply-To:Cc:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=NcR1DITLyZDwVfijh4Itb/klrZ9aX2S8Z/+EATPgWnc=; b=qRWm/zNlS/s/vrfX7y9C9CuuT K/ydTptVeAfZxDkqRACaA5fQ5RJ/xz4rmbgG/tiP52U96Br2DeN1iYAjgNkkFSYoufWKTkda/Nw9D pPrDAMaqDGKbg2REiHXs7OSLpLrX1+wQWrtfcLHhkGWBEwFr3g1Hj7nHnmVCTszLDvBjDZTOw2V3e 764RkvBU7ZX5+H/tN0jqdb0MMuDal/sxoWaK0ElWYxDG8UXaKHb4PJYJbHwIDqgAf5WwU1QL1VcON CBvpWn6rZqSYbjOpzOhLTqe/WdxsAHFZu5BDsjXdgpJe7olGlPm1JCG4qPGpzm4wJDqH7/6l0Cl9P Y9ZWjmE+w==; Received: from [2601:1c0:6280:3f0::34d9] by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1im6sa-000714-DF; Tue, 31 Dec 2019 02:03:28 +0000 Subject: Re: Why is CONFIG_VT forced on? To: Rob Landley , linux-kernel@vger.kernel.org References: <9b79fb95-f20c-f299-f568-0ffb60305f04@landley.net> <018540ef-0327-78dc-ea5c-a43318f1f640@landley.net> <774dfe49-61a0-0144-42b7-c2cbac150687@landley.net> From: Randy Dunlap Message-ID: <8059d1c4-759d-9911-73c7-211f8576e7f2@infradead.org> Date: Mon, 30 Dec 2019 18:03:26 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <774dfe49-61a0-0144-42b7-c2cbac150687@landley.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/30/19 6:04 PM, 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 > > plus of course > > ./arch/x86/Kconfig.cpu: bool "Supported processor vendors" if EXPERT > ./arch/x86/Kconfig: bool "DMA memory allocation support" if EXPERT > ./arch/x86/Kconfig: bool "Enable DMI scanning" if EXPERT > ./arch/x86/Kconfig: bool "Enable support for 16-bit segments" if EXPERT > ./arch/x86/Kconfig: bool "Enable vsyscall emulation" if EXPERT > ./arch/x86/Kconfig: bool "Enable the LDT (local descriptor table)" if EXPERT > ./arch/x86/Kconfig: bool "Read CNB20LE Host Bridge Windows" if EXPERT > ./arch/x86/Kconfig: bool "ISA bus support on modern systems" if EXPERT > ./arch/x86/Kconfig: bool "ISA-style DMA support" if (X86_64 && EXPERT) > > So nobody noticed you have a structural "this config option actually switches > this thing _off_" implemented via magic symbol then? I guess nobody had a problem with it for the last 10 or 15 or 20 years. > I think the right fix here involves running sed after kconfig does its thing... I doubt that would work, but if it does, go for it. -- ~Randy