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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 24B0BC4646D for ; Sat, 11 Aug 2018 09:52:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4360223A6 for ; Sat, 11 Aug 2018 09:52:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=agner.ch header.i=@agner.ch header.b="PkTxWjU5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C4360223A6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=agner.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727335AbeHKM0S (ORCPT ); Sat, 11 Aug 2018 08:26:18 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:49616 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727219AbeHKM0S (ORCPT ); Sat, 11 Aug 2018 08:26:18 -0400 Received: from trochilidae.toradex.int (unknown [37.17.239.3]) by mail.kmu-office.ch (Postfix) with ESMTPSA id 91FAC5C0487; Sat, 11 Aug 2018 11:52:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1533981156; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:content-type:content-transfer-encoding: in-reply-to:references; bh=kFAHeYhN1rRh+fKT4TJKu7jbX2C74qlkpx5L3b2bubw=; b=PkTxWjU5G6GRfATh3vy+t/mOVSB6L71CZjtVuF7U7rvYoq5ccma5/H3Uc809FTglA3DfIW YZ+jF6sKmeQuCyALlBTlGwTM6mA3qLU4mPbrGBwG+tZwK5cmoQuE+P0EvVDLp+ufmtnDTb juI3A5i43uzoPB9H7lnZGzfcbwUuHX8= From: Stefan Agner To: linux@armlinux.org.uk Cc: arnd@arndb.de, mka@chromium.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Stefan Agner Subject: [PATCH] ARM: require GCC for FRAME_POINTER Date: Sat, 11 Aug 2018 11:52:35 +0200 Message-Id: <20180811095235.1938-1-stefan@agner.ch> X-Mailer: git-send-email 2.18.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To produce a meaningful backtrace with FRAME_POINTER enabled the kernel needs a specific function prologue: mov ip, sp stmfd sp!, {fp, ip, lr, pc} sub fp, ip, #4 To get to the required prologue gcc uses apcs and no-sched-prolog. This compiler options are not available on clang, and clang is not able to generate the required prologue. Make the FRAME_POINTER config symbol dependent on GCC. Suggested-by: Arnd Bergmann Signed-off-by: Stefan Agner --- arch/arm/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 693f84392f1b..cb65cf67dfa2 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -54,7 +54,7 @@ config DEBUG_WX # n, but then RMK will have to kill you ;). config FRAME_POINTER bool - depends on !THUMB2_KERNEL + depends on !THUMB2_KERNEL && CC_IS_GCC default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER help If you say N here, the resulting kernel will be slightly smaller and -- 2.18.0