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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 2718EC18E5B for ; Tue, 17 Mar 2020 09:27:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F3D9E20674 for ; Tue, 17 Mar 2020 09:27:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726189AbgCQJ1B (ORCPT ); Tue, 17 Mar 2020 05:27:01 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:53686 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725794AbgCQJ1A (ORCPT ); Tue, 17 Mar 2020 05:27:00 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jE8Ur-0004sf-Uy; Tue, 17 Mar 2020 10:26:50 +0100 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 37F12101161; Tue, 17 Mar 2020 10:26:49 +0100 (CET) From: Thomas Gleixner To: Masami Hiramatsu , Peter Zijlstra Cc: jpoimboe@redhat.com, linux-kernel@vger.kernel.org, x86@kernel.org, Dan Carpenter Subject: Re: [RFC][PATCH 00/16] objtool: vmlinux.o and noinstr validation In-Reply-To: <20200317095628.4f3690afe24e059a146a4b6f@kernel.org> References: <20200312134107.700205216@infradead.org> <20200312162337.GU12561@hirez.programming.kicks-ass.net> <20200317095628.4f3690afe24e059a146a4b6f@kernel.org> Date: Tue, 17 Mar 2020 10:26:49 +0100 Message-ID: <87h7yncox2.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Masami Hiramatsu writes: > BTW, out of curiously, if BUG*() or WARN*() cases happens in the noinstr > section, do we also need to move them (register dump, stack unwinding, > printk, console output, etc.) all into noinstr section? The current plan is to declare BUG()/WARN() "safe". On x86 it is kinda safe as it uses UD2. That raises an exception which handles the bug/warn after establishing the correct state. Of course it's debatable, but moving all of this into the noinstr section might be just a too wide scope. Thanks, tglx