From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754259AbbGXUQU (ORCPT ); Fri, 24 Jul 2015 16:16:20 -0400 Received: from mx2.suse.de ([195.135.220.15]:42579 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753030AbbGXUQS (ORCPT ); Fri, 24 Jul 2015 16:16:18 -0400 Message-ID: <1437768965.3298.52.camel@stgolabs.net> Subject: Re: linux-next: build failure after merge of the akpm-current tree From: Davidlohr Bueso To: Stephen Rothwell , "Paul E. McKenney" Cc: Andrew Morton , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 24 Jul 2015 13:16:05 -0700 In-Reply-To: <20150724153334.543cfc7b@canb.auug.org.au> References: <20150724153334.543cfc7b@canb.auug.org.au> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2015-07-24 at 15:33 +1000, Stephen Rothwell wrote: > Hi Andrew, > > After merging the akpm-current tree, today's linux-next build (powerpc > allnoconfig) failed like this: > > mm/built-in.o: In function `shrink_slab.part.73.constprop.83': > vmscan.c:(.text+0xf760): undefined reference to `__srcu_read_lock' > vmscan.c:(.text+0xf924): undefined reference to `__srcu_read_unlock' > mm/built-in.o: In function `unregister_shrinker': > (.text+0xfa60): undefined reference to `synchronize_srcu' > mm/built-in.o:(.data+0x1e8): undefined reference to `process_srcu' > > Caused by commit > > dab937da82f9 ("mm: srcu-ify shrinkers") > > I have reverted that commit for today. Adding paulmck. I'm not entirely sure what is the fix here. Paul G also reported it failing for arm. I was able to reproduce with powerpc, and the following fixes the issue, but I doubt it is the correct way to address this. The idea was based on how we do it for x86. Also, having SRCU in mm is, lets say, more than convenient, beyond MMU_NOTIFIERS which explicitly selects SRCU. Paul? diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 5ef2711..774207e 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -124,6 +124,7 @@ config PPC select GENERIC_IRQ_SHOW select GENERIC_IRQ_SHOW_LEVEL select IRQ_FORCED_THREADING + select SRCU select HAVE_RCU_TABLE_FREE if SMP select HAVE_SYSCALL_TRACEPOINTS select HAVE_BPF_JIT Thanks, Davidlohr