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=-0.8 required=3.0 tests=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 E2CCAC3F2CD for ; Thu, 5 Mar 2020 15:23:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C160E20848 for ; Thu, 5 Mar 2020 15:23:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726498AbgCEPXq (ORCPT ); Thu, 5 Mar 2020 10:23:46 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:45235 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726243AbgCEPXq (ORCPT ); Thu, 5 Mar 2020 10:23:46 -0500 Received: from b2b-5-147-251-51.unitymedia.biz ([5.147.251.51] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1j9sLc-0006Xj-1j; Thu, 05 Mar 2020 15:23:40 +0000 Date: Thu, 5 Mar 2020 16:23:39 +0100 From: Christian Brauner To: Aleksa Sarai Cc: Florian Weimer , David Howells , linux-api@vger.kernel.org, viro@zeniv.linux.org.uk, metze@samba.org, torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Have RESOLVE_* flags superseded AT_* flags for new syscalls? Message-ID: <20200305152339.3uitms2pua5wzzed@wittgenstein> References: <96563.1582901612@warthog.procyon.org.uk> <20200228152427.rv3crd7akwdhta2r@wittgenstein> <87h7z7ngd4.fsf@oldenburg2.str.redhat.com> <20200302115239.pcxvej3szmricxzu@wittgenstein> <8736arnel9.fsf@oldenburg2.str.redhat.com> <20200302121959.it3iophjavbhtoyp@wittgenstein> <20200302123510.bm3a2zssohwvkaa4@wittgenstein> <87y2sjlygl.fsf@oldenburg2.str.redhat.com> <20200305141154.e246swv62rnctite@yavin> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200305141154.e246swv62rnctite@yavin> Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Fri, Mar 06, 2020 at 01:11:54AM +1100, Aleksa Sarai wrote: > On 2020-03-02, Florian Weimer wrote: > > * Christian Brauner: > > > One difference to openat() is that openat2() doesn't silently ignore > > > unknown flags. But I'm not sure that would matter for iplementing > > > openat() via openat2() since there are no flags that openat() knows about > > > that openat2() doesn't know about afaict. So the only risks would be > > > programs that accidently have a bit set that isn't used yet. > > > > Will there be any new flags for openat in the future? If not, we can > > just use a constant mask in an openat2-based implementation of openat. > > There is one being proposed at the moment as part of the compressed > read/write work[1]. That work predates openat2() having been merged so there's an argument to be made that it should be on top of openat2() imho. But that assumes people agree with https://lore.kernel.org/linux-fsdevel/3607683.1583419401@warthog.procyon.org.uk/T/#m58c1b6c2697e72e7b42bdbea248178ed31b7d787 and I haven't heard anything in either direction... Christian