Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755681AbZJLJo0 (ORCPT ); Mon, 12 Oct 2009 05:44:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755638AbZJLJoZ (ORCPT ); Mon, 12 Oct 2009 05:44:25 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:56170 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755631AbZJLJoZ (ORCPT ); Mon, 12 Oct 2009 05:44:25 -0400 Date: Mon, 12 Oct 2009 11:43:34 +0200 From: Ingo Molnar To: Alexey Dobriyan Cc: Linus Torvalds , Thomas Gleixner , Peter Zijlstra , Linux Kernel Mailing List Subject: Re: Linux 2.6.32-rc4 Message-ID: <20091012094334.GA928@elte.hu> References: <20091012082950.GA2270@elte.hu> <20091012132917.GA4900@x200> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091012132917.GA4900@x200> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4097 Lines: 105 * Alexey Dobriyan wrote: > On Mon, Oct 12, 2009 at 10:29:50AM +0200, Ingo Molnar wrote: > > * Linus Torvalds wrote: > > > > > Alexey Dobriyan (2): > > > headers: remove sched.h from interrupt.h > > > > This commit broke the -rc4 build in numerous ways on x86: > > > > drivers/pci/hotplug/cpqphp.h: In function ???wait_for_ctrl_irq???: > > drivers/pci/hotplug/cpqphp.h:730: error: implicit declaration of function ???signal_pending??? > > > > drivers/char/rtc.c: In function 'rtc_interrupt': > > drivers/char/rtc.c:271: error: 'TASK_INTERRUPTIBLE' undeclared (first use in this function) > > drivers/char/rtc.c:271: error: (Each undeclared identifier is reported only once > > > > (I'll send fixes for the build failures as followups to this mail.) > > > > Beyond being buggy there's two workflow problems with the commit. > > > > Firstly, the commit log concentrates on the m68k situation while in > > reality more testing on x86 would have been much more important to the > > end result. If we break m68k with a header cleanup it's far less of a > > practical problem than if we break thousands of x86 boxes. I find this > > kind of artificially inflated focus on cross-testing (without properly > > weighting platforms) harmful. > > > > Secondly, i'm wondering why the original mail to lkml: > > > > Date: Wed, 7 Oct 2009 17:09:06 +0400 > > From: Alexey Dobriyan > > To: torvalds@linux-foundation.org > > Subject: [PATCH] headers: remove sched.h from interrupt.h > > Cc: linux-kernel@vger.kernel.org > > > > Wasnt Cc:-ed to the affected maintainers? > > To whom? All 42 of them? Nope. If you dont know who generally tends to modify a file you can use scripts/get_maintainer.pl, which gives you applicable Cc lines: earth4:~/tip> scripts/get_maintainer.pl -f include/linux/sched.h Ingo Molnar Peter Zijlstra Andrew Morton linux-kernel@vger.kernel.org earth4:~/tip> scripts/get_maintainer.pl -f include/linux/interrupt.h Ingo Molnar Thomas Gleixner Yinghai Lu Rusty Russell Peter Zijlstra linux-kernel@vger.kernel.org > > As a result the patch wasnt tested by any maintainer tree before it > > was sent to Linus. The change is good but obviously needs to be done > > more carefully, there are a _lot_ of hidden header dependencies in > > the kernel, especially related to sched.h. > > > > We are doing regular header cleanup patches in -tip and have the > > infrastructure to test them properly as well, so this change could > > have been done via either the scheduler tree and the interrupt tree. > > We also cross-test to all other architectures. > > Me too. The problem is that you dont test carefully enough and that you avoid maintainer trees that do. > This patch was tested on ~300 configs (allmodconfigs and defconfigs) > _and_ randconfigs on i386 and x86_64. I'm sorry I don't have more > compile time. > > > Alexey, could you please Cc: affected maintainers in the future, so > > that we can avoid such problems? > > Probably. Probably? You dont know for sure whether you will be able to Cc: affected maintainers in the future? > The problem I have with -tip is that god knows what's in there, git log? > [...] so any header dependency removed might very well be unrelated to > mainline. That's nonsense. It's trivial to tell whether a build failure is caused by a commit in a maintainer tree or whether it came from upstream. Maintainers do this all the time, it's not specific to -tip at all. All the 5 build fixes i sent today were for mainline build breakages you introduced via that patch. Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/