From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C66CC742D2 for ; Mon, 15 Jul 2019 00:37:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A099214C6 for ; Mon, 15 Jul 2019 00:37:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729136AbfGOAhl (ORCPT ); Sun, 14 Jul 2019 20:37:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50680 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729019AbfGOAhe (ORCPT ); Sun, 14 Jul 2019 20:37:34 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5CD843688B; Mon, 15 Jul 2019 00:37:34 +0000 (UTC) Received: from treble.redhat.com (ovpn-120-170.rdu2.redhat.com [10.10.120.170]) by smtp.corp.redhat.com (Postfix) with ESMTP id 501475D9D2; Mon, 15 Jul 2019 00:37:33 +0000 (UTC) From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , Nick Desaulniers , Arnd Bergmann , Jann Horn , Randy Dunlap Subject: [PATCH 06/22] x86/head/64: Annotate start_cpu0() as non-callable Date: Sun, 14 Jul 2019 19:37:01 -0500 Message-Id: In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Mon, 15 Jul 2019 00:37:34 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After an objtool improvement, it complains about the fact that start_cpu0() jumps to code which has an LRET instruction. arch/x86/kernel/head_64.o: warning: objtool: .head.text+0xe4: unsupported instruction in callable function Technically, start_cpu0() is callable, but it acts nothing like a callable function. Prevent objtool from treating it like one by removing its ELF function annotation. Signed-off-by: Josh Poimboeuf --- arch/x86/kernel/head_64.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index bcd206c8ac90..66b4a7757397 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -253,10 +253,10 @@ END(secondary_startup_64) * start_secondary() via .Ljump_to_C_code. */ ENTRY(start_cpu0) - movq initial_stack(%rip), %rsp UNWIND_HINT_EMPTY + movq initial_stack(%rip), %rsp jmp .Ljump_to_C_code -ENDPROC(start_cpu0) +END(start_cpu0) #endif /* Both SMP bootup and ACPI suspend change these variables */ -- 2.20.1