Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754685AbbGQQ5v (ORCPT ); Fri, 17 Jul 2015 12:57:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37044 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754490AbbGQQ5s (ORCPT ); Fri, 17 Jul 2015 12:57:48 -0400 From: Josh Poimboeuf To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Michal Marek , Peter Zijlstra , Andy Lutomirski , Borislav Petkov , Linus Torvalds , Andi Kleen , Pedro Alves , x86@kernel.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 17/21] x86/asm/entry: Fix frame pointer usage in thunk functions Date: Fri, 17 Jul 2015 11:47:33 -0500 Message-Id: <9868088e73dee9dd77810845e14b2f8867a929ef.1437150175.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: 1324 Lines: 47 Thunk functions are callable non-leaf functions that don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Also they aren't annotated as ELF callable functions which can confuse tooling. Create stack frames for them when CONFIG_FRAME_POINTER is enabled and add the ELF function type. Signed-off-by: Josh Poimboeuf --- arch/x86/entry/thunk_64.S | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk_64.S index efb2b93..03ee0cd 100644 --- a/arch/x86/entry/thunk_64.S +++ b/arch/x86/entry/thunk_64.S @@ -8,11 +8,14 @@ #include #include "calling.h" #include +#include /* rdi: arg1 ... normal C conventions. rax is saved/restored. */ .macro THUNK name, func, put_ret_addr_in_rdi=0 .globl \name + .type \name, @function \name: + FRAME /* this one pushes 9 elems, the next one would be %rIP */ pushq %rdi @@ -62,6 +65,7 @@ restore: popq %rdx popq %rsi popq %rdi + ENDFRAME ret _ASM_NOKPROBE(restore) #endif -- 2.1.0 -- 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/