Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5148FC43219 for ; Wed, 12 Jan 2022 07:56:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351299AbiALH4P (ORCPT ); Wed, 12 Jan 2022 02:56:15 -0500 Received: from verein.lst.de ([213.95.11.211]:45167 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237500AbiALH4O (ORCPT ); Wed, 12 Jan 2022 02:56:14 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id BD67E68AFE; Wed, 12 Jan 2022 08:56:09 +0100 (CET) Date: Wed, 12 Jan 2022 08:56:09 +0100 From: Christoph Hellwig To: Arnd Bergmann Cc: Christoph Hellwig , Guo Ren , the arch/x86 maintainers , Linux ARM , Linux Kernel Mailing List , "open list:BROADCOM NVRAM DRIVER" , Parisc List , linuxppc-dev , linux-s390 , sparclinux , linux-arch , Jeff Layton , "J. Bruce Fields" Subject: Re: [PATCH 4/5] uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h Message-ID: <20220112075609.GA4854@lst.de> References: <20220111083515.502308-1-hch@lst.de> <20220111083515.502308-5-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 11, 2022 at 04:33:30PM +0100, Arnd Bergmann wrote: > This is a very subtle change to the exported UAPI header contents: > On 64-bit architectures, the three unusable numbers are now always > shown, rather than depending on a user-controlled symbol. Well, the change is bigger and less subtle. Before this change the constants were never visible to userspace at all (except on mips), because the #ifdef CONFIG_64BIT it never set for userspace builds. > This is probably what we want here for compatibility reasons, but I think > it should be explained in the changelog text, and I'd like Jeff or Bruce > to comment on it as well: the alternative here would be to make the > uapi definition depend on __BITS_PER_LONG==32, which is > technically the right thing to do but more a of a change. I can change this to #if __BITS_PER_LONG==32 || defined(__KERNEL__), but it will still be change in what userspace sees.