From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934912AbdKGBAw (ORCPT ); Mon, 6 Nov 2017 20:00:52 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52672 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932579AbdKFXyK (ORCPT ); Mon, 6 Nov 2017 18:54:10 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Ingo Molnar" , "H. Peter Anvin" , "Thomas Gleixner" , "Linus Torvalds" , "Arnd Bergmann" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 270/294] x86/boot: Add CONFIG_PARAVIRT_SPINLOCKS quirk to arch/x86/boot/compressed/misc.h In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ingo Molnar commit 927392d73a97d8d235bb65400e2e3c7f0bec2b6f upstream. Linus reported the following new warning on x86 allmodconfig with GCC 5.1: > ./arch/x86/include/asm/spinlock.h: In function ‘arch_spin_lock’: > ./arch/x86/include/asm/spinlock.h:119:3: warning: implicit declaration > of function ‘__ticket_lock_spinning’ [-Wimplicit-function-declaration] > __ticket_lock_spinning(lock, inc.tail); > ^ This warning triggers because of these hacks in misc.h: /* * we have to be careful, because no indirections are allowed here, and * paravirt_ops is a kind of one. As it will only run in baremetal anyway, * we just keep it from happening */ #undef CONFIG_PARAVIRT #undef CONFIG_KASAN But these hacks were not updated when CONFIG_PARAVIRT_SPINLOCKS was added, and eventually (with the introduction of queued paravirt spinlocks in recent kernels) this created an invalid Kconfig combination and broke the build. So add a CONFIG_PARAVIRT_SPINLOCKS #undef line as well. Also remove the _ASM_X86_DESC_H quirk: that undocumented quirk was originally added ages ago, in: 099e1377269a ("x86: use ELF format in compressed images.") and I went back to that kernel (and fixed up the main Makefile which didn't build anymore) and checked what failure it avoided: it avoided an include file dependencies related build failure related to our old x86-platforms code. That old code is long gone, the header dependencies got cleaned up, and the build does not fail anymore with the totality of asm/desc.h included - so remove the quirk. Reported-by: Linus Torvalds Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Arnd Bergmann Signed-off-by: Ben Hutchings --- arch/x86/boot/compressed/misc.h | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -2,14 +2,13 @@ #define BOOT_COMPRESSED_MISC_H /* - * we have to be careful, because no indirections are allowed here, and - * paravirt_ops is a kind of one. As it will only run in baremetal anyway, - * we just keep it from happening + * Special hack: we have to be careful, because no indirections are allowed here, + * and paravirt_ops is a kind of one. As it will only run in baremetal anyway, + * we just keep it from happening. (This list needs to be extended when new + * paravirt and debugging variants are added.) */ #undef CONFIG_PARAVIRT -#ifdef CONFIG_X86_32 -#define _ASM_X86_DESC_H 1 -#endif +#undef CONFIG_PARAVIRT_SPINLOCKS #include #include