From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id E483B8E3 for ; Tue, 6 Sep 2016 21:36:51 +0000 (UTC) Received: from mail-lf0-f66.google.com (mail-lf0-f66.google.com [209.85.215.66]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 988B1AF for ; Tue, 6 Sep 2016 21:36:49 +0000 (UTC) Received: by mail-lf0-f66.google.com with SMTP id 29so5129020lfv.1 for ; Tue, 06 Sep 2016 14:36:49 -0700 (PDT) Date: Wed, 7 Sep 2016 00:36:44 +0300 From: Alexey Dobriyan To: Steven Rostedt Message-ID: <20160906213644.GA16732@p183.telecom.by> References: <20160906185143.GF2356@ZenIV.linux.org.uk> <20160906152243.766f3845@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160906152243.766f3845@gandalf.local.home> Cc: ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [topic proposal] tracepoints and ABI stability warranties List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Sep 06, 2016 at 03:22:43PM -0400, Steven Rostedt wrote: > On Tue, 6 Sep 2016 19:51:43 +0100 > Al Viro wrote: > > > I think this is something that needs to be discussed at KS; IMO we > > need at least some way to express the degree of stability promises made > > wrt individual tracepoints and some mechanisms for preventing silent creep > > towards full stability; something along the lines of "unstable tracepoint $FOO > > used by $PROGRAM, kernel tainted", at least. > > What about having a set of tracepoints that are only enabled if one > adds to the kernel command line "this-kernel-is-broken" and a big > printk banner saying something like: The solution was out there for quite some time :-) Scope of Compatibility Packages in Red Hat Enterprise Linux are classified under one of the following four compatibility levels: [ ] Compatibility level 1: APIs and ABIs are stable across three major releases; [ ] Compatibility level 2: APIs and ABIs are stable within one major release. [ ] Compatibility level 3: Reserved for future use. [X] Compatibility level 4: No compatibility is provided. The winning move is to not play and let distros sort it out. P.S.: techically every kernel release almost certainly breaks crash(1) program, program many people on this list should be familiar with. It is unclear why rules should be different for tracepoints.