Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755318AbbHNDQE (ORCPT ); Thu, 13 Aug 2015 23:16:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47576 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754931AbbHNDM6 (ORCPT ); Thu, 13 Aug 2015 23:12:58 -0400 From: Josh Poimboeuf To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org Cc: linux-kernel@vger.kernel.org, Michal Marek , Peter Zijlstra , Andy Lutomirski , Borislav Petkov , Linus Torvalds , Andi Kleen , Pedro Alves , Namhyung Kim , Bernd Petrovitsch , "Chris J Arges" , live-patching@vger.kernel.org Subject: [PATCH v10 10/20] x86/reboot: Add ljmp instructions to stackvalidate whitelist Date: Thu, 13 Aug 2015 22:10:31 -0500 Message-Id: <9edef4f90bf449d572bbd602400e10f0f5e23b32.1439521412.git.jpoimboe@redhat.com> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1551 Lines: 47 stackvalidate reports a false positive warning for the ljmp instruction in machine_real_restart(). Normally, ljmp isn't allowed in a function, but this is a special case where it's jumping into real mode. Add the jumps to a whitelist which tells stackvalidate to ignore them. Signed-off-by: Josh Poimboeuf --- arch/x86/kernel/reboot.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 86db4bc..0931d87 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -97,11 +98,13 @@ void __noreturn machine_real_restart(unsigned int type) /* Jump to the identity-mapped low memory code */ #ifdef CONFIG_X86_32 - asm volatile("jmpl *%0" : : + asm volatile(STACKVALIDATE_IGNORE_INSN + "jmpl *%0;" : : "rm" (real_mode_header->machine_real_restart_asm), "a" (type)); #else - asm volatile("ljmpl *%0" : : + asm volatile(STACKVALIDATE_IGNORE_INSN + "ljmpl *%0" : : "m" (real_mode_header->machine_real_restart_asm), "D" (type)); #endif -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/