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=-5.8 required=3.0 tests=BAYES_00,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 B6CA8C433E0 for ; Mon, 18 Jan 2021 16:41:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79CC422C9D for ; Mon, 18 Jan 2021 16:41:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393532AbhARQlN (ORCPT ); Mon, 18 Jan 2021 11:41:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:50774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390380AbhARQk3 (ORCPT ); Mon, 18 Jan 2021 11:40:29 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8FC26206F7; Mon, 18 Jan 2021 16:39:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610987989; bh=/XyZZytsXsIiGIMUoHK1SO+Ufo+9X9KY7fkU6YpHpwA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Tw83WnlbDVTXWxk7hn9NDqNVAHRTcXQXINm45MJHO+zVdvtg5HQDXdFnyUNrnlaIu QyTbxenJ9dZWdJsbJjDVpGJaTgNaBZLDgeshrm5abzLVYLC20sQoqIqIxBguEsOthM YeUoWr8ZZLyK03Bg3yW4Na7uZjgJHcipLlIy3QGY= Date: Mon, 18 Jan 2021 17:39:46 +0100 From: Greg KH To: Sasha Levin Cc: masahiroy@kernel.org, michal.lkml@markovi.net, torvalds@linux-foundation.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, stable@kernel.org Subject: Re: [PATCH] kbuild: give SUBLEVEL more room in KERNEL_VERSION Message-ID: References: <20210118014951.250815-1-sashal@kernel.org> <20210118133959.GZ4035784@sasha-vm> <20210118153135.GA4035784@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210118153135.GA4035784@sasha-vm> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 18, 2021 at 10:31:35AM -0500, Sasha Levin wrote: > On Mon, Jan 18, 2021 at 02:52:02PM +0100, Greg KH wrote: > > On Mon, Jan 18, 2021 at 08:39:59AM -0500, Sasha Levin wrote: > > > I think it would also affect code that doesn't do things based on > > > SBULEVEL. Consider something like: > > > > > > if (LINUX_VERSION_CODE < KERNEL_VERSION(4,5,0)) > > > > > > Which will cause 4.4.256 to now change the result of that comparison. > > > > Sure, but there are no in-kernel users like this, so my sympathy is > > quite low :) > > Wouldn't it be an issue for the hacky in-kernel users too? For example, > right now the USB code does: > > #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff)) > #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff)) > > After 4.4.256, KERNEL_VER will be (5) rather than (4), indicating a > version of 4.5. Which, really, is just fine. This is an informational string that shows up in 'lsusb' for root hubs. Same for V4L devices, they just want to send some string to userspace. Yes, it might look odd, but nothing is going to break, it's just a string :) thanks, greg k-h