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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 61BB6C433E0 for ; Tue, 16 Mar 2021 21:16:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EA9A664F92 for ; Tue, 16 Mar 2021 21:16:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA9A664F92 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D92D16B006C; Tue, 16 Mar 2021 17:16:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D68306B006E; Tue, 16 Mar 2021 17:16:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C07D96B0070; Tue, 16 Mar 2021 17:16:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0001.hostedemail.com [216.40.44.1]) by kanga.kvack.org (Postfix) with ESMTP id A78046B006C for ; Tue, 16 Mar 2021 17:16:39 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 6AF2F180AD82F for ; Tue, 16 Mar 2021 21:16:39 +0000 (UTC) X-FDA: 77926996518.25.C4572B9 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf22.hostedemail.com (Postfix) with ESMTP id 9DBDFC000C57 for ; Tue, 16 Mar 2021 21:16:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=5gozf9msiE9KxmQI3WyWORDOu9a/cAx+NIytFUdmLig=; b=X/SgE772DCUsq82Z3cmFeX95oO PqfjJ2FRHKtH42r39m6MsvF9e5TdZgVBI17+s6kSwsdLRIH6v9V4li+P1j+8WqrEOiBkH6dTpmXCl zj1Kf2d5mWrKPa8KsbpoPAW1aiwZWNaloYuw/CAIYs+xvotJFNzpXH8o2sLJTPSdxOe8bKxhzoW7R Fj+2vE8z7DbOu1UEzcqo4TMCRdDso4boo0dWkPh4i3GG1J0Wl3oHeTBkK6TokK4mP/RePGYbmcBdt UCFi0He2Yd3bwFvSsH+Qnhs7glJ4VOkYI0qVv+/wM6AHgCid9xL3/c/oJyHftKdVv1DVOVvqYwv5V V7lwKkHg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lMH2e-000dKj-Op; Tue, 16 Mar 2021 21:15:57 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 59827981337; Tue, 16 Mar 2021 22:15:52 +0100 (CET) Date: Tue, 16 Mar 2021 22:15:52 +0100 From: Peter Zijlstra To: Yu-cheng Yu Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang Subject: Re: [PATCH v23 00/28] Control-flow Enforcement: Shadow Stack Message-ID: <20210316211552.GU4746@worktop.programming.kicks-ass.net> References: <20210316151054.5405-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210316151054.5405-1-yu-cheng.yu@intel.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 9DBDFC000C57 X-Stat-Signature: t43qeox7ojqxayrh7pxzs9yt9iee6smj Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf22; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615929398-5353 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Mar 16, 2021 at 08:10:26AM -0700, Yu-cheng Yu wrote: > Control-flow Enforcement (CET) is a new Intel processor feature that blocks > return/jump-oriented programming attacks. Details are in "Intel 64 and > IA-32 Architectures Software Developer's Manual" [1]. > > CET can protect applications and the kernel. This series enables only > application-level protection, and has three parts: > > - Shadow stack [2], > - Indirect branch tracking [3], and > - Selftests [4]. CET is marketing; afaict SS and IBT are 100% independent and there's no reason what so ever to have them share any code, let alone a Kconfig knob. In fact, I think all of this would improve is you remove the CET name from all of this entirely. Put this series under CONFIG_X86_SHSTK (or _SS) and use CONFIG_X86_IBT for the other one. Similarly with the .c file. All this CET business is just pure confusion.