From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f41.google.com (mail-wg0-f41.google.com [74.125.82.41]) by kanga.kvack.org (Postfix) with ESMTP id 3C7316B0069 for ; Thu, 16 Oct 2014 05:25:39 -0400 (EDT) Received: by mail-wg0-f41.google.com with SMTP id b13so3249148wgh.12 for ; Thu, 16 Oct 2014 02:25:38 -0700 (PDT) Received: from mail-wg0-f46.google.com (mail-wg0-f46.google.com [74.125.82.46]) by mx.google.com with ESMTPS id w1si1516624wiz.34.2014.10.16.02.25.37 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 16 Oct 2014 02:25:37 -0700 (PDT) Received: by mail-wg0-f46.google.com with SMTP id l18so3248960wgh.29 for ; Thu, 16 Oct 2014 02:25:37 -0700 (PDT) Date: Thu, 16 Oct 2014 10:25:30 +0100 From: Steve Capper Subject: Re: [PATCH 1/2] mm: Update generic gup implementation to handle hugepage directory Message-ID: <20141016092529.GA1524@linaro.org> References: <1413390888-4934-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1413390888-4934-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: "Aneesh Kumar K.V" Cc: akpm@linux-foundation.org, Andrea Arcangeli , benh@kernel.crashing.org, mpe@ellerman.id.au, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, will.deacon@arm.com, catalin.marinas@arm.com, linux@arm.linux.org.uk On Wed, Oct 15, 2014 at 10:04:47PM +0530, Aneesh Kumar K.V wrote: > Update generic gup implementation with powerpc specific details. > On powerpc at pmd level we can have hugepte, normal pmd pointer > or a pointer to the hugepage directory. > > Signed-off-by: Aneesh Kumar K.V Hi, This patch causes compiler errors on arm and arm64 due to pgd_huge being undefined. I've attached a fixup below, this fixup will require that #define pgd_huge(pgd) 0 be added back into: arch/powerpc/include/asm/page.h For the second patch in this series. Another avenue would be to do something like: #ifndef pgd_huge #define pgd_huge(pgd) (0) #endif Then no changes would be required to arm and arm64 (or other architectures). To help with bisectability, could we please have a suitable fix applied to the two patches in the -mm tree: http://ozlabs.org/~akpm/mmots/broken-out/mm-update-generic-gup-implementation-to-handle-hugepage-directory.patch http://ozlabs.org/~akpm/mmots/broken-out/arch-powerpc-switch-to-generic-rcu-get_user_pages_fast.patch rather than applied afterwards? With pgd_huge(x) defined, this patch passes my futex test on arm (Arndale platform) and arm64(Juno). Cheers, -- Steve