From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id A84826B0005 for ; Thu, 16 Jun 2016 05:32:46 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id e189so94171981pfa.2 for ; Thu, 16 Jun 2016 02:32:46 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id x19si5113489pfi.191.2016.06.16.02.32.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Jun 2016 02:32:36 -0700 (PDT) Date: Thu, 16 Jun 2016 02:32:35 -0700 From: Christoph Hellwig Subject: Re: [PATCH] Revert "mm: rename _count, field of the struct page, to _refcount" Message-ID: <20160616093235.GA14640@infradead.org> References: <1466068966-24620-1-git-send-email-vkuznets@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1466068966-24620-1-git-send-email-vkuznets@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Vitaly Kuznetsov Cc: linux-mm@kvack.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Joonsoo Kim , Andrew Morton , Stephen Rothwell , Vlastimil Babka , Hugh Dickins , Ingo Molnar On Thu, Jun 16, 2016 at 11:22:46AM +0200, Vitaly Kuznetsov wrote: > _count -> _refcount rename in commit 0139aa7b7fa12 ("mm: rename _count, > field of the struct page, to _refcount") broke kdump. makedumpfile(8) does > stuff like READ_MEMBER_OFFSET("page._count", page._count) and fails. While > it is definitely possible to fix this particular tool I'm not sure about > other tools which might be doing the same. > > I suggest we remember the "we don't break userspace" rule and revert for > 4.7 while it's not too late. Err, sorry - this is not "userspace". It's crazy crap digging into kernel internal structure. The rename was absolutely useful, so fix up your stinking pike in kdump. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org