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=-2.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham 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 AFD3DC43381 for ; Wed, 6 Mar 2019 12:50:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7921920652 for ; Wed, 6 Mar 2019 12:50:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="ev5uKQUS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730165AbfCFMuc (ORCPT ); Wed, 6 Mar 2019 07:50:32 -0500 Received: from pandora.armlinux.org.uk ([78.32.30.218]:59620 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726317AbfCFMuc (ORCPT ); Wed, 6 Mar 2019 07:50:32 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding: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=WR0S/PfcH9lLxoKWJu+GgLcUWJNBIIuWZc/DeVg1zag=; b=ev5uKQUSUImCZnLFxWslUIdvF KWcV7cGenVyMyathz8+BGrbknbuTs679sitr1j/+EQzbl8hAkli/k4CJ7G7MZTU78DnH6dro+0Ukh syZRwsECaGXM0NN1ukQWD7yiD/hQYHSNrLA19iWo7eia/ECIiO4G78UUq8Cn4dgfME4x7lNBRNpgG 9SM4ppnuOExQwTkdH4MBMYPRLnnS34NeDqXsIysyY2wrAVOhEjEZ88Z4UAI6wnTq4QaMnKBTm/Afl Q2ujBq0eoqLEcssDKivDynq4o6rs7crB4MkeIRNNFLSIbGP1mKRTCAl1zfreo7xZgSaqAumOkxwn7 JAMYg9rWQ==; Received: from shell.armlinux.org.uk ([2001:4d48:ad52:3201:5054:ff:fe00:4ec]:54980) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1h1W09-0007jK-Mf; Wed, 06 Mar 2019 12:50:25 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.89) (envelope-from ) id 1h1W06-00044X-DV; Wed, 06 Mar 2019 12:50:22 +0000 Date: Wed, 6 Mar 2019 12:50:22 +0000 From: Russell King - ARM Linux admin To: Mark Rutland Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Lucas Stach , Peng Hao , Andy Shevchenko , Greg Kroah-Hartman Subject: Re: Smarter Kconfig help Message-ID: <20190306125022.ikqy66lf25yifxwc@shell.armlinux.org.uk> References: <20190305173111.t3n6ycktht7kxuhq@shell.armlinux.org.uk> <20190306093521.GA50994@lakrids.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190306093521.GA50994@lakrids.cambridge.arm.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mark, On Wed, Mar 06, 2019 at 09:35:21AM +0000, Mark Rutland wrote: > On Tue, Mar 05, 2019 at 05:31:12PM +0000, Russell King - ARM Linux admin wrote: > > Guys, > > Hi Russell, > > > We need to be smarter when writing Kconfig help. I'm just going > > through updating my build trees with the results of 5.0 development, > > and a number of the help texts are next to useless. For example, > > > > PVPANIC - is this something that should be enabled for a host or > > guest kernel? Answer: you have to read the driver code to find out. > > When I looked at the help text: > > This driver provides support for the pvpanic device. pvpanic is > a paravirtualized device provided by QEMU; it lets a virtual machine > (guest) communicate panic events to the host. > > ... it seemed clear to me that this was for a guest, given the text says > QEMU provides the device. I guess you read that as meaning QEMU asks the > host kernel to provide the device to the guest? Yes - that's exactly where the confusion was. It could be something like a tap network device to allow a guest access to a facility on the host, or it could be something that the guest kernel uses to communicate with its host environment. > Do you have a suggestion for how to word that unambiguously? It used to be normal to include a sugestion in the help text that guided when an option should be enabled. So, adding something like: "Say Y here if you are building a kernel for a virtual machine." would make it clear. This used to be standard throughout the kernel, but it seems in recent years, this has been omitted. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up