Received: by 2002:ac0:a5b6:0:0:0:0:0 with SMTP id m51-v6csp2529118imm; Thu, 7 Jun 2018 12:11:00 -0700 (PDT) X-Google-Smtp-Source: ADUXVKJ1jmFgsQeGMTc9+abq0Yw/CHTn/CEuLiGs2J1f8FPPW32K5JexTLcNqWmCXIZDo5HkLbRH X-Received: by 2002:a63:3c4b:: with SMTP id i11-v6mr2569057pgn.414.1528398659999; Thu, 07 Jun 2018 12:10:59 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1528398659; cv=none; d=google.com; s=arc-20160816; b=lVrACKigA8q1GiTaNnmlZQoVBgmKx4APYPHNwkQSBvPRnoGw5rlE3CwIA4xQyBgMzw gKuyhkTbJt/XpHRUznc1St+20B7v+KAQcMhbbU6RnbHzFhVeX4HNLWB8fM0b+NKMmoXZ ug0aRS+hzIJ+WGYgr/ofENihBVPWpmk3tgZqw1x9FkpquzikOTmUImrq291xAxY0JPmw S/ljyyeK0wtiptngS0xCHlZ77Sb/K0bFBKk3aafpKmW5J/INrY2equp/meLa1jis6fpm yMTAwHm2iFc2n8defjnBoU/tebddNgOdOHp0RcMBJPO+F8DiJVbeYEkHWiF9I9B6Y+4x yQzg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature :arc-authentication-results; bh=0qYPRT2XH9Uz0UTBU1jQ2AP/N42sJuTWnRN0wq0a2eQ=; b=ztTna5Jo02RdFkOye4Td97mnegIKpQndLa4k0FWFN59Yv8Th3lDZCv2q2Ljt+GSCVa UuOsgSSYpf1PWSnk9h9/afga75VZkE63gN+O5CKl6Mz3tcowlB+cN8hiLwhdqkuKbiyD 8VTtZovkyaKzWwoDP+0DIe1mUI/G1u3NPYMBYuGjdsgMUB5JTI9ZTxMjOAEWDZaUTuPT uMLlyQ/THm2noFdICdGlXY1Q3uJZLkxhzciyubiPs/WjBjTqI0Y5wp5Qw9N2ckqRpS8m ueLp5JohNWWWwad2hSygz8YZMvUDFQU4tZHZjDpwtMo0ct+fUP/dl806ueGWNXAM0UBa qW4g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gtrF+tr9; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id c3-v6si53873690pld.593.2018.06.07.12.10.45; Thu, 07 Jun 2018 12:10:59 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gtrF+tr9; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932405AbeFGStQ (ORCPT + 99 others); Thu, 7 Jun 2018 14:49:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:36756 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932373AbeFGStN (ORCPT ); Thu, 7 Jun 2018 14:49:13 -0400 Received: from mail-wr0-f181.google.com (mail-wr0-f181.google.com [209.85.128.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 37AF3208B1 for ; Thu, 7 Jun 2018 18:49:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1528397353; bh=crbJkwTStLUzTuNVU01tdjm1kf88uyd/+FByIXqhZu0=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=gtrF+tr9mtgO+zr88VaZ6BT8kt3AaVa7gphT4iuEFeJp00TBxtk6D44BsMuImftsc d1soH5MA1tI1EaR5/mg8HyeTT9TS0d4lHoXhc9Y3QBw4sF4Zk5LFARZ1wJe3/FAf6S EcixHyvokfTTSW5PfaN7I14raG8S12jVMfs3418M= Received: by mail-wr0-f181.google.com with SMTP id w10-v6so10869592wrk.9 for ; Thu, 07 Jun 2018 11:49:13 -0700 (PDT) X-Gm-Message-State: APt69E2g84mT/K8fbVHAI76W8J2ntx9I65fW57IzjyfhRtWgguT5hzIb I9vSFtxB4PeuwqyOE52DVCas9stBl6i0aCC/gdhSLA== X-Received: by 2002:adf:e084:: with SMTP id c4-v6mr2563276wri.199.1528397351735; Thu, 07 Jun 2018 11:49:11 -0700 (PDT) MIME-Version: 1.0 References: <20180607143807.3611-1-yu-cheng.yu@intel.com> <20180607143807.3611-9-yu-cheng.yu@intel.com> In-Reply-To: <20180607143807.3611-9-yu-cheng.yu@intel.com> From: Andy Lutomirski Date: Thu, 7 Jun 2018 11:48:59 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 08/10] mm: Prevent mremap of shadow stack To: Yu-cheng Yu Cc: LKML , linux-doc@vger.kernel.org, Linux-MM , linux-arch , X86 ML , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , "H. J. Lu" , "Shanbhogue, Vedvyas" , "Ravi V. Shankar" , Dave Hansen , Jonathan Corbet , Oleg Nesterov , Arnd Bergmann , mike.kravetz@oracle.com 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 Thu, Jun 7, 2018 at 7:41 AM Yu-cheng Yu wrote: > > Signed-off-by: Yu-cheng Yu Please justify. This seems actively harmful to me.