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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable 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 42384C282CE for ; Mon, 11 Feb 2019 19:01:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 00A1920863 for ; Mon, 11 Feb 2019 19:01:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="AF/C1MIM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 00A1920863 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 89D718E0135; Mon, 11 Feb 2019 14:01:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 827568E0138; Mon, 11 Feb 2019 14:01:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6F0528E0135; Mon, 11 Feb 2019 14:01:17 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by kanga.kvack.org (Postfix) with ESMTP id 134EA8E012D for ; Mon, 11 Feb 2019 14:01:17 -0500 (EST) Received: by mail-wr1-f72.google.com with SMTP id f5so440136wrt.13 for ; Mon, 11 Feb 2019 11:01:17 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:date:from:to:cc:subject :message-id:references:mime-version:content-disposition:in-reply-to :user-agent; bh=qWpDfY9hdZigS4Dtjg1dc7Cbm4tCe4w1qekSQJB7WTQ=; b=SFyxuuHQvuHNx6x++M1ON0DKiv4T/bOX4rpmXwQlYFyHR4FrXIErYhKBDt5hJ2K0Ye aTPXXNH23p9i250+22ZESp5MmoT6+rvAx5i5PG7vs9iGgAgcwgwfwuNFbTktV1uqqaM4 Umh06lQBeSKUwonqwYgehRy8gL790uK77UhQfxHlLxbW9tq6lXDCU0ZEE6l6lKgLo8Bp c2ZtatJdw92t6LZWeJlNVpbnrG0374xzbpVVHn9YC3DHAWEqOWKMP2wqURhmS8wKg540 4mLUUyUEjtwrtlxsk5AqDe2cAhmbSqbKtqCR6YMvJaSkDfgl0zjq1RB9w80AsQ+l5E0a rc2g== X-Gm-Message-State: AHQUAuZkDq520INguWnpJuirFDKpLFSIz8JT5qFFu48yNJQkEQfjw1Mn cKpTTkBHmQfPSoKGhkCrQtRS+bqA0gaZPrntXPcl1UZgVcKBZNIX709NzuAhRu1N/pAS20lxs6c rpxz7ZF0MpRUm3Po4TSvuB4xX7zKZZ/o5PX4uxYkPQIz45o+P+np61t3tVeMTc4VngA== X-Received: by 2002:a05:6000:10cf:: with SMTP id b15mr28345100wrx.301.1549911676638; Mon, 11 Feb 2019 11:01:16 -0800 (PST) X-Google-Smtp-Source: AHgI3IYDJYTri+4kAMwwLaGJav88SYOLM11fvzmWpv+hIwJK1Nl6W5odcaJRjC2QLbt4YSaxZUzT X-Received: by 2002:a05:6000:10cf:: with SMTP id b15mr28345042wrx.301.1549911675596; Mon, 11 Feb 2019 11:01:15 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1549911675; cv=none; d=google.com; s=arc-20160816; b=tCQ2FT2pdPAh7f3M0qf5SwtsyhZJziLIdYDI0l1b5slo0JPZkxPtqceqcpP/nRM4J/ iGeUSCiU6c6Ah6KWnXn9uwAueQ7d/1jMXg9STg3vSOMvqiXlKt++nixsffpAqRoFE1VL 2giH/lrZCyAfcp839GByHAQpu3hSSDSTsgqjVVGXzNOCXpLH8/SgGJo/Ihx8xK564MTy GQp9AEOMA9eRlWmTnYtcAyXFS4MqgZI3K4RhVJUi5VPSndx5RniEfDD59qANLR0ld4MV GlRnPLZ5WnMvZfWwx/dAqlGExWDRRZMuH8cWVMXt//rJ6RDz5YceaM9hrDq8cTnIZh0m 7kBg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:dkim-signature; bh=qWpDfY9hdZigS4Dtjg1dc7Cbm4tCe4w1qekSQJB7WTQ=; b=HoS7g+W+rT0d9aXQg6LkyVZ6jc3u/j/sW/diN+LDAxEixnbSfaAcFlj2NTTOvNdjIn 2MX4qz2Ss4iQOER2n5fQ0hP/HtSlxuDGrm1r/gBHTqFrMysWjeGI+bK+NDyxq3Lbj7Mm oNRIIOvcmTMD+gzpYnrR3/kwP+66rZt/y1gFmLPMAQq501Gi+kQ+e8TEp57l+DAs1JNY IlKWBAlcAfZxgZ7te/d4liFrkoWTCiogeIGQIJ6iQdKQEB+NonXw4agAI8h8mxkUzfbo +6vl4XLXdCE64+38q7crMYhaNR5hufGpDN0qiodk36cX/moXN+pYdbY3n8zEWKvk/RF/ 5NWA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@alien8.de header.s=dkim header.b="AF/C1MIM"; spf=pass (google.com: domain of bp@alien8.de designates 2a01:4f8:190:11c2::b:1457 as permitted sender) smtp.mailfrom=bp@alien8.de; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alien8.de Received: from mail.skyhub.de (mail.skyhub.de. [2a01:4f8:190:11c2::b:1457]) by mx.google.com with ESMTPS id a16si105272wmd.137.2019.02.11.11.01.15 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 Feb 2019 11:01:15 -0800 (PST) Received-SPF: pass (google.com: domain of bp@alien8.de designates 2a01:4f8:190:11c2::b:1457 as permitted sender) client-ip=2a01:4f8:190:11c2::b:1457; Authentication-Results: mx.google.com; dkim=pass header.i=@alien8.de header.s=dkim header.b="AF/C1MIM"; spf=pass (google.com: domain of bp@alien8.de designates 2a01:4f8:190:11c2::b:1457 as permitted sender) smtp.mailfrom=bp@alien8.de; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alien8.de Received: from zn.tnic (p200300EC2BC7A10074DEFDFE3AD6CF32.dip0.t-ipconnect.de [IPv6:2003:ec:2bc7:a100:74de:fdfe:3ad6:cf32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 99AB21EC01AF; Mon, 11 Feb 2019 20:01:14 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1549911674; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=qWpDfY9hdZigS4Dtjg1dc7Cbm4tCe4w1qekSQJB7WTQ=; b=AF/C1MIM5X+09YOUt8D3qKn3HVAOfhn+qR7SVoJP7VlW/9RiKKb8XDrl7Zd3X4x34F3OWA itb3pR9IU1oePmeRJRAkXZ9WkBzL2B8pr0SohcMKAN8/JjHenMUuFOgfVr3peRm/Rlddxu SFxivBRbCkhNC48c5HPHOLAKykBGhLw= Date: Mon, 11 Feb 2019 20:01:08 +0100 From: Borislav Petkov To: Nadav Amit Cc: Rick Edgecombe , Andy Lutomirski , Ingo Molnar , LKML , X86 ML , "H. Peter Anvin" , Thomas Gleixner , Dave Hansen , Peter Zijlstra , Damian Tometzki , linux-integrity , LSM List , Andrew Morton , Kernel Hardening , Linux-MM , Will Deacon , Ard Biesheuvel , Kristen Carlson Accardi , "Dock, Deneen T" , Kees Cook , Dave Hansen , Masami Hiramatsu Subject: Re: [PATCH v2 10/20] x86: avoid W^X being broken during modules loading Message-ID: <20190211190108.GP19618@zn.tnic> References: <20190129003422.9328-1-rick.p.edgecombe@intel.com> <20190129003422.9328-11-rick.p.edgecombe@intel.com> <20190211182956.GN19618@zn.tnic> <1533F2BB-2284-499B-9912-6D74D0B87BC1@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1533F2BB-2284-499B-9912-6D74D0B87BC1@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) 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 Mon, Feb 11, 2019 at 10:45:26AM -0800, Nadav Amit wrote: > Are you sure about that? This path is still used when modules are loaded. Yes, I'm sure. Loading a module does a gazillion things so saving a couple of insns - yes, boot_cpu_has() is usually a RIP-relative MOV and a TEST - doesn't show even as a blip on any radar. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.