From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752677AbcEBCtN (ORCPT ); Sun, 1 May 2016 22:49:13 -0400 Received: from e18.ny.us.ibm.com ([129.33.205.208]:58038 "EHLO e18.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751771AbcEBCtD (ORCPT ); Sun, 1 May 2016 22:49:03 -0400 X-IBM-Helo: d01dlp02.pok.ibm.com X-IBM-MailFrom: paulmck@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;target-devel@vger.kernel.org Date: Sun, 1 May 2016 19:49:02 -0700 From: "Paul E. McKenney" To: hch@infradead.org Cc: falakreyaz@gmail.com, nab@linux-iscsi.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Fw: [rcu:rcu/next 41/41] arch/x86/kvm/vmx.c:11022:2: error: function '_r_a_p__v' is initialized like a variable Message-ID: <20160502024902.GR3686@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16050202-0045-0000-0000-00000413F87E X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Like this sort of compiler bug, maybe. Compiles just fine on my laptop. Thoughts? Thanx, Paul ----- Forwarded message from kbuild test robot ----- Date: Mon, 2 May 2016 10:12:38 +0800 From: kbuild test robot Cc: kbuild-all@01.org, "Paul E. McKenney" Subject: [rcu:rcu/next 41/41] arch/x86/kvm/vmx.c:11022:2: error: function '_r_a_p__v' is initialized like a variable tree: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/next head: 16d7afcaa5301f8243a7dda82be4d59e84ac6ee1 commit: 16d7afcaa5301f8243a7dda82be4d59e84ac6ee1 [41/41] rcu: No ordering for rcu_assign_pointer() of NULL config: x86_64-rhel (attached as .config) compiler: gcc-4.9 (Debian 4.9.3-14) 4.9.3 reproduce: git checkout 16d7afcaa5301f8243a7dda82be4d59e84ac6ee1 # save the attached .config to linux build tree make ARCH=x86_64 Note: the rcu/rcu/next HEAD 16d7afcaa5301f8243a7dda82be4d59e84ac6ee1 builds fine. It only hurts bisectibility. All error/warnings (new ones prefixed by >>): arch/x86/kvm/vmx.c: In function 'vmx_init': >> arch/x86/kvm/vmx.c:11022:2: error: function '_r_a_p__v' is initialized like a variable rcu_assign_pointer(crash_vmclear_loaded_vmcss, ^ In file included from include/linux/rbtree.h:34:0, from include/linux/mm_types.h:9, from arch/x86/kvm/irq.h:25, from arch/x86/kvm/vmx.c:19: >> include/linux/rcupdate.h:657:45: warning: the comparison will always evaluate as 'false' for the address of '_r_a_p__v' will never be NULL [-Waddress] if (__builtin_constant_p(v) && (_r_a_p__v) == NULL) \ ^ >> arch/x86/kvm/vmx.c:11022:2: note: in expansion of macro 'rcu_assign_pointer' rcu_assign_pointer(crash_vmclear_loaded_vmcss, ^ >> include/linux/rcupdate.h:655:12: error: nested function '_r_a_p__v' declared but never defined typeof(v) _r_a_p__v = (v); \ ^ >> arch/x86/kvm/vmx.c:11022:2: note: in expansion of macro 'rcu_assign_pointer' rcu_assign_pointer(crash_vmclear_loaded_vmcss, ^ In file included from arch/x86/kvm/vmx.c:25:0: arch/x86/kvm/vmx.c: At top level: >> include/linux/module.h:130:6: error: 'init_module' aliased to undefined symbol 'vmx_init' int init_module(void) __attribute__((alias(#initfn))); ^ >> arch/x86/kvm/vmx.c:11039:1: note: in expansion of macro 'module_init' module_init(vmx_init) ^ vim +/_r_a_p__v +11022 arch/x86/kvm/vmx.c 34a1cd60 arch/x86/kvm/vmx.c Tiejun Chen 2014-10-28 11016 int r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx), 0ee75bea arch/x86/kvm/vmx.c Avi Kivity 2010-04-28 11017 __alignof__(struct vcpu_vmx), THIS_MODULE); fdef3ad1 drivers/kvm/vmx.c He, Qing 2007-04-30 11018 if (r) 34a1cd60 arch/x86/kvm/vmx.c Tiejun Chen 2014-10-28 11019 return r; 25c5f225 arch/x86/kvm/vmx.c Sheng Yang 2008-03-28 11020 2965faa5 arch/x86/kvm/vmx.c Dave Young 2015-09-09 11021 #ifdef CONFIG_KEXEC_CORE 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 @11022 rcu_assign_pointer(crash_vmclear_loaded_vmcss, 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11023 crash_vmclear_local_loaded_vmcss); 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11024 #endif 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11025 fdef3ad1 drivers/kvm/vmx.c He, Qing 2007-04-30 11026 return 0; 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11027 } 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11028 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11029 static void __exit vmx_exit(void) 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11030 { 2965faa5 arch/x86/kvm/vmx.c Dave Young 2015-09-09 11031 #ifdef CONFIG_KEXEC_CORE 3b63a43f arch/x86/kvm/vmx.c Monam Agarwal 2014-03-22 11032 RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL); 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11033 synchronize_rcu(); 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11034 #endif 8f536b76 arch/x86/kvm/vmx.c Zhang Yanfei 2012-12-06 11035 cb498ea2 drivers/kvm/vmx.c Zhang Xiantao 2007-11-14 11036 kvm_exit(); 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11037 } 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11038 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 @11039 module_init(vmx_init) 6aa8b732 drivers/kvm/vmx.c Avi Kivity 2006-12-10 11040 module_exit(vmx_exit) :::::: The code at line 11022 was first introduced by commit :::::: 8f536b7697a0d40ef6b5fd04cf2c04953d5ca06f KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump :::::: TO: Zhang Yanfei :::::: CC: Gleb Natapov --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation ----- End forwarded message -----