From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753699AbaEHLGG (ORCPT ); Thu, 8 May 2014 07:06:06 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:26044 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753177AbaEHLGE (ORCPT ); Thu, 8 May 2014 07:06:04 -0400 Date: Thu, 8 May 2014 12:05:27 +0100 From: Catalin Marinas To: Stefano Stabellini Cc: David Vrabel , Julien Grall , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xenproject.org" , Ian Campbell , "konrad.wilk@oracle.com" Subject: Re: [PATCH] arm/xen: Remove definiition of virt_to_pfn in asm/xen/page.h Message-ID: <20140508110527.GE17344@arm.com> References: <1397836474-10478-1-git-send-email-julien.grall@linaro.org> <535901F0.3010908@citrix.com> <53590845.1090405@linaro.org> <53591B8F.8070300@citrix.com> <536A1CF8.5000309@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 07, 2014 at 05:58:21PM +0100, Stefano Stabellini wrote: > On Wed, 7 May 2014, David Vrabel wrote: > > On 07/05/14 12:41, Stefano Stabellini wrote: > > > On Fri, 25 Apr 2014, Stefano Stabellini wrote: > > >> On Thu, 24 Apr 2014, David Vrabel wrote: > > >>> On 24/04/14 13:49, Julien Grall wrote: > > >>>> Hi David, > > >>>> > > >>>> On 04/24/2014 01:22 PM, David Vrabel wrote: > > >>>>> On 18/04/14 16:54, Julien Grall wrote: > > >>>>>> virt_to_pfn has been defined in asm/memory.h by the commit e26a9e0 "ARM: Better > > >>>>>> virt_to_page() handling" > > >>>>>> > > >>>>>> This will result of a compilation warning when CONFIG_XEN is enabled. > > >>>>>> > > >>>>>> arch/arm/include/asm/xen/page.h:80:0: warning: "virt_to_pfn" redefined [enabled by default] > > >>>>>> #define virt_to_pfn(v) (PFN_DOWN(__pa(v))) > > >>>>>> ^ > > >>>>>> In file included from arch/arm/include/asm/page.h:163:0, > > >>>>>> from arch/arm/include/asm/xen/page.h:4, > > >>>>>> from include/xen/page.h:4, > > >>>>>> from arch/arm/xen/grant-table.c:33: > > >>>>>> > > >>>>>> The definition in memory.h is nearly the same (it directly expand PFN_DOWN), > > >>>>>> so we can safely drop virt_to_pfn in xen include. > > >>>>> > > >>>>> > > >>>>> This breaks the arm build for me. > > >>>>> > > >>>>> /local/davidvr/work/k.org/tip/drivers/block/xen-blkfront.c: In function > > >>>>> ‘setup_blkring’: > > >>>>> /local/davidvr/work/k.org/tip/drivers/block/xen-blkfront.c:1236:2: > > >>>>> error: implicit declaration of function ‘virt_to_pfn’ > > >>>>> [-Werror=implicit-function-declaration] > > >>>>> err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring)); > > >>>>> ^ > > >>>> > > >>>> I don't have any issue to build the following branch with this patch on: > > >>>> - v3.15-rc2 > > >>>> - xentip master > > >>>> - xentip for-linus-3.16 > > >>> > > >>> Applied to devel/for-linus-3.16. > > >>> > > >>> If something else turns up for 3.15 (and I remember) I'll take it for > > >>> 3.15 instead. > > >> > > >> David, > > >> thank you very much for taking the patch in my absence. > > >> > > >> Considering that the problem is affecting everybody enabling CONFIG_XEN > > >> on ARM on v3.15, I don't think we can wait for the next merge window to > > >> send this fix upstream. > > >> Too many warnings for too many people. > > > > > > Unfortunately this commit breaks arm64 compilation, as virt_to_pfn has > > > not been introduced to arm64/include/asm/memory.h. > > > Has the patch been sent upstream yet? > > > > No. > > > > > We need this additional change for arm64: > > > > > > diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h > > > index e94f945..993bce5 100644 > > > --- a/arch/arm64/include/asm/memory.h > > > +++ b/arch/arm64/include/asm/memory.h > > > @@ -138,6 +138,7 @@ static inline void *phys_to_virt(phys_addr_t x) > > > #define __pa(x) __virt_to_phys((unsigned long)(x)) > > > #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) > > > #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) > > > +#define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys(x)) > > > > This would need an ack from an arm64 maintainer. > > Certainly. Catalin is in CC. Acked-by: Catalin Marinas