From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933574Ab3GPQnJ (ORCPT ); Tue, 16 Jul 2013 12:43:09 -0400 Received: from mail.lang.hm ([64.81.33.126]:55970 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933369Ab3GPQnF (ORCPT ); Tue, 16 Jul 2013 12:43:05 -0400 Date: Tue, 16 Jul 2013 09:42:34 -0700 (PDT) From: David Lang X-X-Sender: dlang@asgard.lang.hm To: Takashi Iwai cc: Willy Tarreau , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, ksummit-2013-discuss@lists.linux-foundation.org, torvalds@linux-foundation.org Subject: Re: [Ksummit-2013-discuss] When to push bug fixes to mainline In-Reply-To: Message-ID: References: <20130711214830.611455274@linuxfoundation.org> <20130712005023.GB31005@thunk.org> <20130712051451.GC25815@1wt.eu> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 16 Jul 2013, Takashi Iwai wrote: > At Tue, 16 Jul 2013 00:19:16 -0700 (PDT), > David Lang wrote: >> >> On Fri, 12 Jul 2013, Willy Tarreau wrote: >> >>> And maybe in the end, having 1/10 patch cause a regression is not *that* >>> dramatic, and probably less than not fixing the 9 other bugs. In one case >>> we rely on -stable to merge the 10 fixes, and on the other case we'd rely >>> on -stable to just revert one of them. >> >> Apologies for the late post, I'm catching up on things, but this jumped out at >> me. >> >> We went through a LOT of pain several years ago when people got into the mindset >> that a patch was acceptable if it fixed more people than it broke. eliminating >> that mindset did wonders for kernel stability. >> >> Regressions are a lot more of a negative than bugfixes are a positive, a 10:1 >> ratio of fixes to regressions is _not_ good enough. > > IMO, one of the reasons is the nature of stable-release: the stable > tree is released soon after reviews of patches, so no actual > regression tests can be done before the release. > > For finding a regression, patch reviews won't be enough; all patches > have been already reviewed, thus essentially they must be all > positive/good fixes. And the compile is OK. So what's the problem? > > Maybe some QA period before the release might help, but who would > care? (Especially under the situation where everybody has own x.y > stable tree?) I am not saying that no regressions will happen (for exactly the reasons that you are giving). what I am complaining about is the attitude that a few regressions are Ok, as long as there are more fixes than there are regressions. David Lang