From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f178.google.com (mail-lb0-f178.google.com [209.85.217.178]) by kanga.kvack.org (Postfix) with ESMTP id 8729B6B0032 for ; Thu, 22 Jan 2015 18:49:39 -0500 (EST) Received: by mail-lb0-f178.google.com with SMTP id u10so4379050lbd.9 for ; Thu, 22 Jan 2015 15:49:38 -0800 (PST) Received: from mail-la0-x236.google.com (mail-la0-x236.google.com. [2a00:1450:4010:c03::236]) by mx.google.com with ESMTPS id yv9si19470024lbb.103.2015.01.22.15.49.37 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 22 Jan 2015 15:49:37 -0800 (PST) Received: by mail-la0-f54.google.com with SMTP id hv19so4541294lab.13 for ; Thu, 22 Jan 2015 15:49:36 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20150122144147.019eedc41f189eac44c3c4cd@freescale.com> References: <20150120140200.aa7ba0eb28d95e456972e178@freescale.com> <20150120230150.GA14475@cloud> <20150120160738.edfe64806cc8b943beb1dfa0@linux-foundation.org> <20150122014550.GA21444@js1304-P5Q-DELUXE> <20150122144147.019eedc41f189eac44c3c4cd@freescale.com> Date: Fri, 23 Jan 2015 08:49:36 +0900 Message-ID: Subject: Re: [PATCH 2/2] mm: fix undefined reference to `.kernel_map_pages' on PPC builds From: Akinobu Mita Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Kim Phillips Cc: Joonsoo Kim , Andrew Morton , josh@joshtriplett.org, Johannes Weiner , Minchan Kim , Rik van Riel , Sasha Levin , Al Viro , Konstantin Khlebnikov , Jens Axboe , linux-mm@kvack.org, LKML , linuxppc-dev 2015-01-23 5:41 GMT+09:00 Kim Phillips : > On Thu, 22 Jan 2015 10:45:51 +0900 > Joonsoo Kim wrote: > >> On Wed, Jan 21, 2015 at 09:57:59PM +0900, Akinobu Mita wrote: >> > 2015-01-21 9:07 GMT+09:00 Andrew Morton : >> > > On Tue, 20 Jan 2015 15:01:50 -0800 josh@joshtriplett.org wrote: >> > > >> > >> On Tue, Jan 20, 2015 at 02:02:00PM -0600, Kim Phillips wrote: >> > >> > It's possible to configure DEBUG_PAGEALLOC without PAGE_POISONING on >> > >> > ppc. Fix building the generic kernel_map_pages() implementation in >> > >> > this case: >> > >> > >> > >> > LD init/built-in.o >> > >> > mm/built-in.o: In function `free_pages_prepare': >> > >> > mm/page_alloc.c:770: undefined reference to `.kernel_map_pages' >> > >> > mm/built-in.o: In function `prep_new_page': >> > >> > mm/page_alloc.c:933: undefined reference to `.kernel_map_pages' >> > >> > mm/built-in.o: In function `map_pages': >> > >> > mm/compaction.c:61: undefined reference to `.kernel_map_pages' >> > >> > make: *** [vmlinux] Error 1 >> > >> > kernel_map_pages() is static inline function since commit 031bc5743f15 >> > ("mm/debug-pagealloc: make debug-pagealloc boottime configurable"). >> > >> > But there is old declaration in 'arch/powerpc/include/asm/cacheflush.h'. >> > Removing it or changing s/kernel_map_pages/__kernel_map_pages/ in this >> > header file or something can fix this problem? >> > >> > The architecture which has ARCH_SUPPORTS_DEBUG_PAGEALLOC >> > including PPC should not build mm/debug-pagealloc.o >> >> Yes, architecture with ARCH_SUPPORTS_DEBUG_PAGEALLOC should not build >> mm/debug-pagealloc.o. I attach the patch to remove old declaration. >> I hope it will fix Kim's problem. >> >> -------------->8------------------ >> From 7cb9d1ed8a785df152cb8934e187031c8ebd1bb2 Mon Sep 17 00:00:00 2001 >> From: Joonsoo Kim >> Date: Thu, 22 Jan 2015 10:28:58 +0900 >> Subject: [PATCH] mm/debug_pagealloc: fix build failure on ppc and some other >> archs >> >> Kim Phillips reported following build failure. >> >> LD init/built-in.o >> mm/built-in.o: In function `free_pages_prepare': >> mm/page_alloc.c:770: undefined reference to `.kernel_map_pages' >> mm/built-in.o: In function `prep_new_page': >> mm/page_alloc.c:933: undefined reference to `.kernel_map_pages' >> mm/built-in.o: In function `map_pages': >> mm/compaction.c:61: undefined reference to `.kernel_map_pages' >> make: *** [vmlinux] Error 1 >> >> Reason for this problem is that commit 031bc5743f15 >> ("mm/debug-pagealloc: make debug-pagealloc boottime configurable") forgot >> to remove old declaration of kernel_map_pages() in some architectures. >> This patch removes them to fix build failure. >> >> Reported-by: Kim Phillips >> Signed-off-by: Joonsoo Kim >> --- > > Thanks. Now I get this: > > LD init/built-in.o > mm/built-in.o: In function `kernel_map_pages': > include/linux/mm.h:2076: undefined reference to `.__kernel_map_pages' > include/linux/mm.h:2076: undefined reference to `.__kernel_map_pages' > include/linux/mm.h:2076: undefined reference to `.__kernel_map_pages' > Makefile:925: recipe for target 'vmlinux' failed > make: *** [vmlinux] Error 1 > > but, AFAICT, that's not because this patch is invalid: it's because > __kernel_map_pages() isn't implemented in > arch/powerpc/mm/pgtable_64.c, i.e., for non-PPC_STD_MMU_64 PPC64 > machines. Then, in order to use generic __kernel_map_pages() in mm/debug-pagealloc.c, CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC shouldn't be selected in arch/powerpc/Kconfig, when CONFIG_PPC_STD_MMU_64 isn't defined. -- 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