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=-7.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 CBBD1C433E1 for ; Tue, 25 Aug 2020 23:34:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 926CC20706 for ; Tue, 25 Aug 2020 23:34:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 926CC20706 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 387988D0002; Tue, 25 Aug 2020 19:34:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3368F6B0007; Tue, 25 Aug 2020 19:34:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 225968D0002; Tue, 25 Aug 2020 19:34:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 0DA0C6B0006 for ; Tue, 25 Aug 2020 19:34:32 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id C3430180AD807 for ; Tue, 25 Aug 2020 23:34:31 +0000 (UTC) X-FDA: 77190697542.30.cloth71_2615c852705f Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin30.hostedemail.com (Postfix) with ESMTP id 8F419180B3AA7 for ; Tue, 25 Aug 2020 23:34:31 +0000 (UTC) X-HE-Tag: cloth71_2615c852705f X-Filterd-Recvd-Size: 3830 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf10.hostedemail.com (Postfix) with ESMTP for ; Tue, 25 Aug 2020 23:34:30 +0000 (UTC) IronPort-SDR: dAJEP44niUJk0U0c77a7NHxwKi8YdapwmAnbAAjxPr2ksZW+8kXusxSyv4UKM4UAhTVGtjMsBq bbA1lYOe0pjQ== X-IronPort-AV: E=McAfee;i="6000,8403,9724"; a="135762932" X-IronPort-AV: E=Sophos;i="5.76,354,1592895600"; d="scan'208";a="135762932" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Aug 2020 16:34:29 -0700 IronPort-SDR: jDH1O40YY4lOk1YRVka2qfIczRRKbt6rlwfRgT/NIKrAOgYtq0SF7EEESuwd0piSxHaIIvjQiR Ag1HGEmIkTmw== X-IronPort-AV: E=Sophos;i="5.76,354,1592895600"; d="scan'208";a="336668677" Received: from yyu32-mobl1.amr.corp.intel.com (HELO [10.213.162.112]) ([10.213.162.112]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Aug 2020 16:34:28 -0700 Subject: Re: [PATCH v11 25/25] x86/cet/shstk: Add arch_prctl functions for shadow stack To: Dave Hansen , Andy Lutomirski Cc: X86 ML , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , LKML , "open list:DOCUMENTATION" , Linux-MM , linux-arch , Linux API , Arnd Bergmann , 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 , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang References: <20200825002540.3351-1-yu-cheng.yu@intel.com> <20200825002540.3351-26-yu-cheng.yu@intel.com> <2d253891-9393-44d0-35e0-4b9a2da23cec@intel.com> <086c73d8-9b06-f074-e315-9964eb666db9@intel.com> <73c2211f-8811-2d9f-1930-1c5035e6129c@intel.com> From: "Yu, Yu-cheng" Message-ID: Date: Tue, 25 Aug 2020 16:34:27 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US X-Rspamd-Queue-Id: 8F419180B3AA7 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 Content-Transfer-Encoding: quoted-printable 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 8/25/2020 4:20 PM, Dave Hansen wrote: > On 8/25/20 2:04 PM, Yu, Yu-cheng wrote: >>>> I think this is more arch-specific.=C2=A0 Even if it becomes a new s= yscall, >>>> we still need to pass the same parameters. >>> >>> Right, but without the copying in and out of memory. >>> >> Linux-api is already on the Cc list.=C2=A0 Do we need to add more peop= le to >> get some agreements for the syscall? > What kind of agreement are you looking for? I'd suggest just coding it > up and posting the patches. Adding syscalls really is really pretty > straightforward and isn't much code at all. >=20 Sure, I will do that. Thanks, Yu-cheng