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=-5.3 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 73B97C43462 for ; Tue, 18 May 2021 19:45:29 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0BEB561285 for ; Tue, 18 May 2021 19:45:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BEB561285 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 9EC208E0042; Tue, 18 May 2021 15:45:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9C4CE8E002F; Tue, 18 May 2021 15:45:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 88D358E0042; Tue, 18 May 2021 15:45:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0054.hostedemail.com [216.40.44.54]) by kanga.kvack.org (Postfix) with ESMTP id 5780D8E002F for ; Tue, 18 May 2021 15:45:28 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id F3FD18249980 for ; Tue, 18 May 2021 19:45:27 +0000 (UTC) X-FDA: 78155381136.02.C541FEE Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by imf11.hostedemail.com (Postfix) with ESMTP id 7ED4720003B4 for ; Tue, 18 May 2021 19:45:24 +0000 (UTC) IronPort-SDR: dZ1RZ37crUI+6z3b6qYT6u8nlvUc022IZ2BdiRBKSPgZAkUIUkkMzR44FGNvf3VBNT9Dtk7BvO cUQE3kRqBvwQ== X-IronPort-AV: E=McAfee;i="6200,9189,9988"; a="200850336" X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="200850336" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2021 12:45:18 -0700 IronPort-SDR: tYQi2B82XedKDm6qGiBjeEUdZVyLSN3ijHw1VG6+3/gOUcVnRwKduMlDNvjLJFTLm5urO60hXJ V5q6mwSq98IA== X-IronPort-AV: E=Sophos;i="5.82,310,1613462400"; d="scan'208";a="439600915" Received: from yyu32-mobl1.amr.corp.intel.com (HELO [10.209.166.158]) ([10.209.166.158]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2021 12:45:16 -0700 Subject: Re: [PATCH v26 24/30] x86/cet/shstk: Introduce shadow stack token setup/verify routines To: Borislav Petkov , Eugene Syromiatnikov 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 , Cyrill Gorcunov , Dave Hansen , 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 , Pengfei Xu , Haitao Huang References: <20210427204315.24153-1-yu-cheng.yu@intel.com> <20210427204315.24153-25-yu-cheng.yu@intel.com> <20210518001316.GR15897@asgard.redhat.com> From: "Yu, Yu-cheng" Message-ID: <10f74571-f8c4-9b08-0157-1570b30a1a6d@intel.com> Date: Tue, 18 May 2021 12:45:13 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Authentication-Results: imf11.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf11.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.24) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 7ED4720003B4 X-Stat-Signature: q8zsfshm84i616f3c9xai53xjx1zoogc X-HE-Tag: 1621367124-953439 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 5/18/2021 10:58 AM, Borislav Petkov wrote: > On Tue, May 18, 2021 at 02:14:14AM +0200, Eugene Syromiatnikov wrote: >> Speaking of which, I wonder what would happen if a 64-bit process makes >> a 32-bit system call (using int 0x80, for example), and gets a signal. > > I guess that's the next patch. And I see amluto has some concerns... > > /me goes read. > In the next revision, there will be no "signal context extension" struct. However, the flow for 64, ia32 and x32 will be similar. I will send that out after some testing. Thanks, Yu-cheng