From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: linux-next: build failure after merge of the tip tree Date: Mon, 20 Jan 2014 09:30:21 +0100 Message-ID: <20140120083021.GC30183@twins.programming.kicks-ass.net> References: <20140116145829.5e4fcab103b1c5c77501ee77@canb.auug.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from merlin.infradead.org ([205.233.59.134]:50448 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751031AbaATIap (ORCPT ); Mon, 20 Jan 2014 03:30:45 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-next-owner@vger.kernel.org List-ID: To: Len Brown Cc: Stephen Rothwell , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-next@vger.kernel.org, "linux-kernel@vger.kernel.org" On Sun, Jan 19, 2014 at 08:00:19PM -0500, Len Brown wrote: > On Wed, Jan 15, 2014 at 10:58 PM, Stephen Rothwell wrote: > > Hi all, > > > > After merging the tip tree, today's linux-next build (x86_64 allmodconfig) > > failed like this: > > > > arch/x86/kernel/process.c: In function 'mwait_idle': > > /scratch/sfr/next/arch/x86/kernel/process.c:434:3: error: implicit declaration of function '__monitor' [-Werror=implicit-function-declaration] > > __monitor((void *)¤t_thread_info()->flags, 0, 0); > > ^ > > arch/x86/kernel/process.c:437:4: error: implicit declaration of function '__sti_mwait' [-Werror=implicit-function-declaration] > > __sti_mwait(0, 0); > > ^ > > > > Caused by commit 16824255394f ("x86, acpi, idle: Restructure the mwait > > idle routines") interacting with commit 7760518cce95 ("x86 idle: restore > > mwait_idle()") from the idle tree. > > > > I am not sure how to fix this so I just reverted the idle tree commit for > > now (since it reverted cleanly). Please let me know if there is a better > > solution. > > IMO, a regression fix (restore mwait_idle()) is more important than a clean up > (restructure mwait routines), and the clean-up should take a back seat; > in -tip, in -next, upstream, and in -stable. It was part of that other regression fix, the 50+ watt thingy for your broken EX chips. It was also written much earlier and widely mailed and published before you did the core2 thing. > Also, I'm wondering if that clean-up went too far -- as not all users of mwait > are necessarily under the same conditions... Then make them so. The fact was that most of the mwait idle sites were bloody broken. And the single mwait_idle_with_hints() function presents a single nice function that does all the required magics.