From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753663AbcB2LAF (ORCPT ); Mon, 29 Feb 2016 06:00:05 -0500 Received: from torg.zytor.com ([198.137.202.12]:52840 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752180AbcB2LAD (ORCPT ); Mon, 29 Feb 2016 06:00:03 -0500 Date: Mon, 29 Feb 2016 02:58:41 -0800 From: tip-bot for Josh Poimboeuf Message-ID: Cc: bp@alien8.de, jslaby@suse.cz, akpm@linux-foundation.org, mingo@kernel.org, peterz@infradead.org, linux-kernel@vger.kernel.org, namhyung@gmail.com, acme@kernel.org, luto@kernel.org, bernd@petrovitsch.priv.at, jpoimboe@redhat.com, palves@redhat.com, chris.j.arges@canonical.com, tglx@linutronix.de, hpa@zytor.com, mmarek@suse.cz, torvalds@linux-foundation.org Reply-To: jslaby@suse.cz, bp@alien8.de, linux-kernel@vger.kernel.org, namhyung@gmail.com, akpm@linux-foundation.org, mingo@kernel.org, peterz@infradead.org, acme@kernel.org, jpoimboe@redhat.com, palves@redhat.com, bernd@petrovitsch.priv.at, luto@kernel.org, chris.j.arges@canonical.com, tglx@linutronix.de, torvalds@linux-foundation.org, mmarek@suse.cz, hpa@zytor.com In-Reply-To: <34487a17b23dba43c50941599d47054a9584b219.1456719558.git.jpoimboe@redhat.com> References: <34487a17b23dba43c50941599d47054a9584b219.1456719558.git.jpoimboe@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:core/objtool] objtool: Add STACK_FRAME_NON_STANDARD() macro Git-Commit-ID: 9a99417acbad99ba6c6a9389b45a53a4d002bb7e X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 9a99417acbad99ba6c6a9389b45a53a4d002bb7e Gitweb: http://git.kernel.org/tip/9a99417acbad99ba6c6a9389b45a53a4d002bb7e Author: Josh Poimboeuf AuthorDate: Sun, 28 Feb 2016 22:22:35 -0600 Committer: Ingo Molnar CommitDate: Mon, 29 Feb 2016 08:35:10 +0100 objtool: Add STACK_FRAME_NON_STANDARD() macro Add a new macro, STACK_FRAME_NON_STANDARD(), which is used to denote a function which does something unusual related to its stack frame. Use of the macro prevents objtool from emitting a false positive warning. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/34487a17b23dba43c50941599d47054a9584b219.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/vmlinux.lds.S | 5 ++++- include/linux/frame.h | 23 +++++++++++++++++++++++ 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 92dc211..13fa0ad 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -343,7 +343,10 @@ SECTIONS /* Sections to be discarded */ DISCARDS - /DISCARD/ : { *(.eh_frame) } + /DISCARD/ : { + *(.eh_frame) + *(__func_stack_frame_non_standard) + } } diff --git a/include/linux/frame.h b/include/linux/frame.h new file mode 100644 index 0000000..e6baaba --- /dev/null +++ b/include/linux/frame.h @@ -0,0 +1,23 @@ +#ifndef _LINUX_FRAME_H +#define _LINUX_FRAME_H + +#ifdef CONFIG_STACK_VALIDATION +/* + * This macro marks the given function's stack frame as "non-standard", which + * tells objtool to ignore the function when doing stack metadata validation. + * It should only be used in special cases where you're 100% sure it won't + * affect the reliability of frame pointers and kernel stack traces. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ +#define STACK_FRAME_NON_STANDARD(func) \ + static void __used __section(__func_stack_frame_non_standard) \ + *__func_stack_frame_non_standard_##func = func + +#else /* !CONFIG_STACK_VALIDATION */ + +#define STACK_FRAME_NON_STANDARD(func) + +#endif /* CONFIG_STACK_VALIDATION */ + +#endif /* _LINUX_FRAME_H */