From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752232AbZEAFQu (ORCPT ); Fri, 1 May 2009 01:16:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750877AbZEAFQl (ORCPT ); Fri, 1 May 2009 01:16:41 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:45596 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750778AbZEAFQl (ORCPT ); Fri, 1 May 2009 01:16:41 -0400 Date: Thu, 30 Apr 2009 22:13:22 -0700 From: Andrew Morton To: Nikanth Karthikesan , mingo@elte.hu, jens.axboe@oracle.com, linux-kernel@vger.kernel.org, Rusty Russell Subject: Re: [PATCH] Detect and warn on atomic_inc/atomic_dec wrapping around Message-Id: <20090430221322.a3080bbd.akpm@linux-foundation.org> In-Reply-To: <20090430220648.268ab9bb.akpm@linux-foundation.org> References: <200904291221.40361.knikanth@novell.com> <200904301939.51022.knikanth@novell.com> <20090430144526.10b3039a.akpm@linux-foundation.org> <200905011027.46754.knikanth@novell.com> <20090430220648.268ab9bb.akpm@linux-foundation.org> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 30 Apr 2009 22:06:48 -0700 Andrew Morton wrote: > On Fri, 1 May 2009 10:27:46 +0530 Nikanth Karthikesan wrote: > > > I tried with linux/bug.h. But it creates a cyclic dependency. linux/bug.h > > pulls in linux/module.h => linux/spinlock.h => asm/spinlock.h (which uses > > atomic_inc) => asm/atomic.h,. > > And why on earth does bug.h need module.h? > > int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, > struct module *); > > The ever-smelly Elf_Ehdr and Elf_Shdr. > > Probably the module_bug_finalize/module_bug_cleanup declarations and > definitions should be in module.h. > I queued the below. I _guess_ it's an improvement - bug.h is a quite low-level thing. I don't yet know what will explode as a result. From: Andrew Morton They're in linux/bug.h at present, which causes include order tangles. In particular, linux/bug.h cannot be used by linux/atomic.h because, according to Nikanth: linux/bug.h pulls in linux/module.h => linux/spinlock.h => asm/spinlock.h (which uses atomic_inc) => asm/atomic.h. bug.h is a pretty low-level thing and module.h is a higher-level thing, IMO. Cc: Nikanth Karthikesan Cc: Rusty Russell Signed-off-by: Andrew Morton --- include/linux/bug.h | 12 ------------ include/linux/module.h | 17 +++++++++++++++++ 2 files changed, 17 insertions(+), 12 deletions(-) diff -puN include/linux/bug.h~headers-move-module_bug_finalize-module_bug_cleanup-definitions-into-moduleh include/linux/bug.h --- a/include/linux/bug.h~headers-move-module_bug_finalize-module_bug_cleanup-definitions-into-moduleh +++ a/include/linux/bug.h @@ -1,7 +1,6 @@ #ifndef _LINUX_BUG_H #define _LINUX_BUG_H -#include #include enum bug_trap_type { @@ -24,10 +23,6 @@ const struct bug_entry *find_bug(unsigne enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs); -int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, - struct module *); -void module_bug_cleanup(struct module *); - /* These are defined by the architecture */ int is_valid_bugaddr(unsigned long addr); @@ -38,13 +33,6 @@ static inline enum bug_trap_type report_ { return BUG_TRAP_TYPE_BUG; } -static inline int module_bug_finalize(const Elf_Ehdr *hdr, - const Elf_Shdr *sechdrs, - struct module *mod) -{ - return 0; -} -static inline void module_bug_cleanup(struct module *mod) {} #endif /* CONFIG_GENERIC_BUG */ #endif /* _LINUX_BUG_H */ diff -puN include/linux/module.h~headers-move-module_bug_finalize-module_bug_cleanup-definitions-into-moduleh include/linux/module.h --- a/include/linux/module.h~headers-move-module_bug_finalize-module_bug_cleanup-definitions-into-moduleh +++ a/include/linux/module.h @@ -696,4 +696,21 @@ static inline void module_remove_modinfo #define __MODULE_STRING(x) __stringify(x) + +#ifdef CONFIG_GENERIC_BUG +int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, + struct module *); +void module_bug_cleanup(struct module *); + +#else /* !CONFIG_GENERIC_BUG */ + +static inline int module_bug_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *mod) +{ + return 0; +} +static inline void module_bug_cleanup(struct module *mod) {} +#endif /* CONFIG_GENERIC_BUG */ + #endif /* _LINUX_MODULE_H */ _