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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 2623FC432C3 for ; Fri, 15 Nov 2019 18:34:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F234F20730 for ; Fri, 15 Nov 2019 18:34:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="DPVoi3lq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726997AbfKOSel (ORCPT ); Fri, 15 Nov 2019 13:34:41 -0500 Received: from mail-vs1-f68.google.com ([209.85.217.68]:46320 "EHLO mail-vs1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726075AbfKOSek (ORCPT ); Fri, 15 Nov 2019 13:34:40 -0500 Received: by mail-vs1-f68.google.com with SMTP id m6so6931356vsn.13 for ; Fri, 15 Nov 2019 10:34:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=z/RQj5FqYPBFFb/BHpJq3oq0/JIX3F5mcr3Ic1KDLoA=; b=DPVoi3lqXCZqeWh9romeMaws5hqXk7f+VlyR9XfhSR/9BdSIhcYmEux7SQ5St6jgAv Qy7JHhLn5W/E49pgWgOuvApN0oQk7kKUVdvzqM0GYzY6xGnHrcu3/C3H75y46ixSvuca LjPAO51k95incrTQsuJOy8ZRL6zlZ92V+cSt7WAY8zd/QGfPmISheb/46Q0qXikywE7H 4Xh/pOiL99Mk+H/Q9TdrDS1OLq9XHIwJxh3HXyW7oVjDzKgHZwFJFMojZFKSuD9lUD8s TsrwyDeDC5tuRiLuIUH3CjrVYpkyH7ytqD6EnefisDfsVDoa6xNUGa6ZrfAwBeh0RQqM vZrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=z/RQj5FqYPBFFb/BHpJq3oq0/JIX3F5mcr3Ic1KDLoA=; b=dpjIMXImc0HQtWl1gSvlMRaA/jUTq1f7LpZv1AV1iWOCQh/TNqEbFPgMRjRh14LbIh /twRYy7g3KMi+LMTIY95+NqJGfiIxmx4bOFqo/XB3j4IOZ0s5jX2Mp2+COSbe7tQIjPL S1Ke8MZdjoN54vGjzIbv8a8N9uxUrTkRl8+ZnquxeIJ5EYrYGcBjG1sHCH2S6nLl4FUR ZFJQOC3mZva2XUqOkRfoJ4SyswE/DFpZrYIY3K71ddtmziZZOEk6UZq6B5kY2eazt93b dnox+XE9R2sfF9Z4dBhqIBOE3+vkY0hFoSxypLwzW4MZf2Jd6dxPNPfeCgmVZI3rfO6Y N0kQ== X-Gm-Message-State: APjAAAVWLAFy/FfnpPemzcnKE2AZQWDJQg/9LyRCzxnhIkr4wE8V8DeW zWuxR/ikWFDzLO6ZBVrXZn9LJJLTBxTDTMJYLk3rHw== X-Google-Smtp-Source: APXvYqy9ZihhNwSz15zAc2n9wuqx0KKCFEmVQyQmPiar9gQiv4PEvu699gEh+PcCmRyXpyUO7fCyzGA8P+JoII/zuY4= X-Received: by 2002:a67:e951:: with SMTP id p17mr5243152vso.112.1573842878866; Fri, 15 Nov 2019 10:34:38 -0800 (PST) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191105235608.107702-1-samitolvanen@google.com> <20191105235608.107702-6-samitolvanen@google.com> <20191115153705.GJ41572@lakrids.cambridge.arm.com> In-Reply-To: <20191115153705.GJ41572@lakrids.cambridge.arm.com> From: Sami Tolvanen Date: Fri, 15 Nov 2019 10:34:25 -0800 Message-ID: Subject: Re: [PATCH v5 05/14] add support for Clang's Shadow Call Stack (SCS) To: Mark Rutland Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux , Kernel Hardening , linux-arm-kernel , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 15, 2019 at 7:37 AM Mark Rutland wrote: > > +config SHADOW_CALL_STACK_VMAP > > + bool > > + depends on SHADOW_CALL_STACK > > + help > > + Use virtually mapped shadow call stacks. Selecting this option > > + provides better stack exhaustion protection, but increases per-thread > > + memory consumption as a full page is allocated for each shadow stack. > > The bool needs some display text to make it selectable. > > This should probably be below SHADOW_CALL_STACK so that when it shows up > in menuconfig it's where you'd expect it to be. > > I locally hacked that in, but when building defconfig + > SHADOW_CALL_STACK + SHADOW_CALL_STACK_VMAP, the build explodes as below: Ugh, thanks for pointing this out. I'll fix this in v6. Sami