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=-3.8 required=3.0 tests=BAYES_00, 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 340CBC2D0A8 for ; Wed, 23 Sep 2020 13:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C5AF52220D for ; Wed, 23 Sep 2020 13:23:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726500AbgIWNXJ (ORCPT ); Wed, 23 Sep 2020 09:23:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726130AbgIWNXI (ORCPT ); Wed, 23 Sep 2020 09:23:08 -0400 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97A9BC0613CE; Wed, 23 Sep 2020 06:23:08 -0700 (PDT) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kL4jW-004YbY-CV; Wed, 23 Sep 2020 13:22:54 +0000 Date: Wed, 23 Sep 2020 14:22:54 +0100 From: Al Viro To: Pavel Begunkov Cc: Arnd Bergmann , Andy Lutomirski , Christoph Hellwig , Andrew Morton , Jens Axboe , David Howells , linux-arm-kernel , X86 ML , LKML , "open list:MIPS" , Parisc List , linuxppc-dev , linux-s390 , sparclinux , linux-block , Linux SCSI List , Linux FS Devel , linux-aio , io-uring@vger.kernel.org, linux-arch , Linux-MM , Network Development , keyrings@vger.kernel.org, LSM List Subject: Re: [PATCH 1/9] kernel: add a PF_FORCE_COMPAT flag Message-ID: <20200923132254.GI3421308@ZenIV.linux.org.uk> References: <563138b5-7073-74bc-f0c5-b2bad6277e87@gmail.com> <486c92d0-0f2e-bd61-1ab8-302524af5e08@gmail.com> <91209170-dcb4-d9ee-afa0-a819f8877b86@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <91209170-dcb4-d9ee-afa0-a819f8877b86@gmail.com> Sender: Al Viro Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Wed, Sep 23, 2020 at 11:01:34AM +0300, Pavel Begunkov wrote: > > I'm not following why that would be considered a valid option, > > as that clearly breaks existing users that update from a 32-bit > > kernel to a 64-bit one. > > Do you mean users who move 32-bit binaries (without recompiling) to a > new x64 kernel? Does the kernel guarantees that to work? Yes. No further (printable) comments for now...