From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from terminus.zytor.com (terminus.zytor.com [IPv6:2001:1868:205::10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 0D2382C0103 for ; Fri, 10 Aug 2012 01:35:18 +1000 (EST) Message-ID: <5023D60F.7010009@zytor.com> Date: Thu, 09 Aug 2012 08:23:59 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 To: "Kirill A. Shutemov" Subject: Re: [PATCH v2 4/6] x86: Add clear_page_nocache References: <1344524583-1096-1-git-send-email-kirill.shutemov@linux.intel.com> <1344524583-1096-5-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1344524583-1096-5-git-send-email-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Cc: Andrea Arcangeli , linux-mips@linux-mips.org, Andi Kleen , Alex Shi , Robert Richter , linuxppc-dev@lists.ozlabs.org, x86@kernel.org, Hugh Dickins , linux-kernel@vger.kernel.org, Jan Beulich , Andy Lutomirski , linux-mm@kvack.org, linux-sh@vger.kernel.org, Ingo Molnar , Mel Gorman , Johannes Weiner , sparclinux@vger.kernel.org, Thomas Gleixner , Tim Chen , Andrew Morton , KAMEZAWA Hiroyuki List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 08/09/2012 08:03 AM, Kirill A. Shutemov wrote: > From: Andi Kleen > > Add a cache avoiding version of clear_page. Straight forward integer variant > of the existing 64bit clear_page, for both 32bit and 64bit. > > Also add the necessary glue for highmem including a layer that non cache > coherent architectures that use the virtual address for flushing can > hook in. This is not needed on x86 of course. > > If an architecture wants to provide cache avoiding version of clear_page > it should to define ARCH_HAS_USER_NOCACHE to 1 and implement > clear_page_nocache() and clear_user_highpage_nocache(). > Compile failure: /home/hpa/kernel/tip.x86-mm/arch/x86/mm/fault.c: In function ‘clear_user_highpage_nocache’: /home/hpa/kernel/tip.x86-mm/arch/x86/mm/fault.c:1215:30: error: ‘KM_USER0’ undeclared (first use in this function) /home/hpa/kernel/tip.x86-mm/arch/x86/mm/fault.c:1215:30: note: each undeclared identifier is reported only once for each function it appears in /home/hpa/kernel/tip.x86-mm/arch/x86/mm/fault.c:1215:2: error: too many arguments to function ‘kmap_atomic’ In file included from /home/hpa/kernel/tip.x86-mm/include/linux/pagemap.h:10:0, from /home/hpa/kernel/tip.x86-mm/include/linux/mempolicy.h:70, from /home/hpa/kernel/tip.x86-mm/include/linux/hugetlb.h:15, from /home/hpa/kernel/tip.x86-mm/arch/x86/mm/fault.c:14: /home/hpa/kernel/tip.x86-mm/include/linux/highmem.h:66:21: note: declared here make[4]: *** [arch/x86/mm/fault.o] Error 1 make[3]: *** [arch/x86/mm] Error 2 make[2]: *** [arch/x86] Error 2 make[1]: *** [sub-make] Error 2 make[1]: Leaving directory `/home/hpa/kernel/tip.x86-mm' This happens on *all* my test configurations, including both x86-64 and i386 allyesconfig. I suspect your patchset base is stale. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.