From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: linux-next: build failure after merge of the tip tree Date: Sun, 19 Jan 2014 17:07:04 -0800 Message-ID: <52DC76B8.7050808@zytor.com> References: <20140116145829.5e4fcab103b1c5c77501ee77@canb.auug.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from terminus.zytor.com ([198.137.202.10]:37778 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752166AbaATBIZ (ORCPT ); Sun, 19 Jan 2014 20:08:25 -0500 In-Reply-To: Sender: linux-next-owner@vger.kernel.org List-ID: To: Len Brown , Stephen Rothwell Cc: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , linux-next@vger.kernel.org, "linux-kernel@vger.kernel.org" On 01/19/2014 05:00 PM, 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. > > Also, I'm wondering if that clean-up went too far -- as not all users of mwait > are necessarily under the same conditions... > Sounds like a NAK to me, in which case that bit should probably be deferred and reintroduced after fixing via the idle tree? -hpa