From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f41.google.com (mail-wm0-f41.google.com [74.125.82.41]) by kanga.kvack.org (Postfix) with ESMTP id 46F256B0258 for ; Fri, 4 Dec 2015 18:14:28 -0500 (EST) Received: by wmuu63 with SMTP id u63so80032376wmu.0 for ; Fri, 04 Dec 2015 15:14:27 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id ch4si21584107wjb.109.2015.12.04.15.14.26 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 04 Dec 2015 15:14:26 -0800 (PST) Date: Fri, 4 Dec 2015 15:14:24 -0800 From: Andrew Morton Subject: Re: [linux-next:master 4174/4356] kernel/built-in.o:undefined reference to `mmap_rnd_bits' Message-Id: <20151204151424.e73641da44c61f20f10d93e9@linux-foundation.org> In-Reply-To: <201512050045.l2G9WhTi%fengguang.wu@intel.com> References: <201512050045.l2G9WhTi%fengguang.wu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: kbuild test robot Cc: Daniel Cashman , kbuild-all@01.org, Mark Brown , Linux Memory Management List On Sat, 5 Dec 2015 00:18:47 +0800 kbuild test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: dcccebc04ddba852aad354270986d508e8f011c0 > commit: a8f025e63718534d6a9224a0b069b772ef21cb5d [4174/4356] arm: mm: support ARCH_MMAP_RND_BITS > config: arm-vf610m4_defconfig (attached as .config) > reproduce: > wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > git checkout a8f025e63718534d6a9224a0b069b772ef21cb5d > # save the attached .config to linux build tree > make.cross ARCH=arm > > All errors (new ones prefixed by >>): > > >> kernel/built-in.o:(.data+0x754): undefined reference to `mmap_rnd_bits' > >> kernel/built-in.o:(.data+0x76c): undefined reference to `mmap_rnd_bits_min' > >> kernel/built-in.o:(.data+0x770): undefined reference to `mmap_rnd_bits_max' OK, the patches are pretty broken when HAVE_ARCH_MMAP_RND_BITS=n. I guess a pile of new ifdefs need adding for this case. There's also the matter of CONFIG_MMU=n. mm/mmap.o doesn't get included in the build in this case, so that will also break things. I suggest that can be fixed by making HAVE_ARCH_MMAP_RND_BITS and HAVE_ARCH_MMAP_RND_COMPAT_BITS depend on MMU. That should fix things up when combined with the new ifdef-sprinkling. This stuff is going to break quite a lot of test builds so I think I'll consolidate the patches then drop 'em for now. -- 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