From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id DD9456B0279 for ; Tue, 13 Mar 2018 10:45:39 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id p128so5317762pga.19 for ; Tue, 13 Mar 2018 07:45:39 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id m5si207712pgv.487.2018.03.13.07.45.38 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 13 Mar 2018 07:45:38 -0700 (PDT) Date: Tue, 13 Mar 2018 15:45:36 +0100 From: Michal Hocko Subject: Re: [PATCH] memory-failure: fix section mismatch Message-ID: <20180313144536.GC4811@dhcp22.suse.cz> References: <20180304071613.16899-1-nick.desaulniers@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180304071613.16899-1-nick.desaulniers@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: Nick Desaulniers Cc: Andrew Morton , Dan Williams , "Kirill A. Shutemov" , Jan Kara , =?iso-8859-1?B?Suly9G1l?= Glisse , Hugh Dickins , Matthew Wilcox , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Sat 03-03-18 23:16:11, Nick Desaulniers wrote: > Clang complains when a variable is declared extern twice, but with two > different sections. num_poisoned_pages is marked extern and __read_mostly > in include/linux/swapops.h, but only extern in include/linux/mm.h. Some > c source files must include both, and thus see the conflicting > declarations. Why do we need declarations in both places? This sounds like a mess to me. > Signed-off-by: Nick Desaulniers > --- > include/linux/mm.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index ad06d42adb1a..bd4bd59f02c1 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -2582,7 +2582,7 @@ extern int get_hwpoison_page(struct page *page); > extern int sysctl_memory_failure_early_kill; > extern int sysctl_memory_failure_recovery; > extern void shake_page(struct page *p, int access); > -extern atomic_long_t num_poisoned_pages; > +extern atomic_long_t num_poisoned_pages __read_mostly; > extern int soft_offline_page(struct page *page, int flags); > > > -- > 2.14.1 > -- Michal Hocko SUSE Labs