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=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 9714FC433E2 for ; Tue, 1 Sep 2020 16:06:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C12D20866 for ; Tue, 1 Sep 2020 16:06:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731678AbgIAQGn (ORCPT ); Tue, 1 Sep 2020 12:06:43 -0400 Received: from foss.arm.com ([217.140.110.172]:44880 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731549AbgIAQGc (ORCPT ); Tue, 1 Sep 2020 12:06:32 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DC8E81045; Tue, 1 Sep 2020 09:06:31 -0700 (PDT) Received: from C02TD0UTHF1T.local (unknown [10.57.10.252]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DF7303F71F; Tue, 1 Sep 2020 09:06:28 -0700 (PDT) Date: Tue, 1 Sep 2020 17:06:26 +0100 From: Mark Rutland To: Mark Brown Cc: Catalin Marinas , Will Deacon , Vasily Gorbik , Heiko Carstens , Borislav Petkov , Thomas Gleixner , "H. Peter Anvin" , Christian Borntraeger , Ingo Molnar , Jiri Slaby , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Miroslav Benes Subject: Re: [PATCH v2 0/3] arm64: Convert to ARCH_STACKWALK Message-ID: <20200901160626.GE95447@C02TD0UTHF1T.local> References: <20200819124913.37261-1-broonie@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200819124913.37261-1-broonie@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Aug 19, 2020 at 01:49:10PM +0100, Mark Brown wrote: > This series updates the arm64 stacktrace code to use the newer and much > simpler arch_stack_walk() interface, the main benefit being a single > entry point to the arch code with no need for the arch code to worry > about skipping frames. Along the way I noticed that the reliable > parameter to the arch_stack_walk() callback appears to be redundant > so there's also a patch here removing that from the existing code to > simplify the interface. > > This is preparatory work for implementing reliable stack trace for > arm64. This all looks pretty nice! Just to check, has the skipping logic been tested to work equivalently to what we had before? By inspection I think it should, but since it relies on function call boundaries it always strikes me as fragile. If you could confirm that (e.g. with LKDTM perhaps?) that'd be great. Assuming that looks right, for the series: Acked-by: Mark Rutland Mark. > > v2: Rebase onto v5.9-rc1. > > Mark Brown (3): > stacktrace: Remove reliable argument from arch_stack_walk() callback > arm64: stacktrace: Make stack walk callback consistent with generic > code > arm64: stacktrace: Convert to ARCH_STACKWALK > > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/stacktrace.h | 2 +- > arch/arm64/kernel/perf_callchain.c | 6 +-- > arch/arm64/kernel/return_address.c | 8 +-- > arch/arm64/kernel/stacktrace.c | 84 ++++------------------------- > arch/s390/kernel/stacktrace.c | 4 +- > arch/x86/kernel/stacktrace.c | 10 ++-- > include/linux/stacktrace.h | 5 +- > kernel/stacktrace.c | 8 ++- > 9 files changed, 30 insertions(+), 98 deletions(-) > > -- > 2.20.1 >