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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 D7442C4360C for ; Fri, 4 Oct 2019 09:45:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC669215EA for ; Fri, 4 Oct 2019 09:45:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="lsrK3yQq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388475AbfJDJpU (ORCPT ); Fri, 4 Oct 2019 05:45:20 -0400 Received: from mail.skyhub.de ([5.9.137.197]:58984 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388388AbfJDJpT (ORCPT ); Fri, 4 Oct 2019 05:45:19 -0400 Received: from zn.tnic (p200300EC2F0C7700A886458DB1699599.dip0.t-ipconnect.de [IPv6:2003:ec:2f0c:7700:a886:458d:b169:9599]) (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 512CC1EC0B59; Fri, 4 Oct 2019 11:45:18 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1570182318; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4fjavIWUE7bcCsSR2gUXUpZ+AhGZW8WM0D0bMXAAJTE=; b=lsrK3yQqWIovY51s2Gd51Ja0zlGWC+RfoXQeEt/1uBJMK3ZGB0QcCyHmzujej+2RlTkKVo DIYpoA7k8SxJxBw7tRQL1/OI5LBxjxu8FkJCHbi30HPzbZEube81+KrYTV47MMVzf4ils1 GZbKhCPnWYI04ddZ7p7z3h8jGMMUeA0= Date: Fri, 4 Oct 2019 11:45:13 +0200 From: Borislav Petkov To: Jarkko Sakkinen Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org, akpm@linux-foundation.org, dave.hansen@intel.com, sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com, rientjes@google.com, cedric.xing@intel.com Subject: Re: [PATCH v22 07/24] x86/sgx: Add wrappers for ENCLS leaf functions Message-ID: <20191004094513.GA3362@zn.tnic> References: <20190903142655.21943-1-jarkko.sakkinen@linux.intel.com> <20190903142655.21943-8-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190903142655.21943-8-jarkko.sakkinen@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 03, 2019 at 05:26:38PM +0300, Jarkko Sakkinen wrote: > ENCLS is a ring 0 instruction that contains a set of leaf functions for > managing enclaves [1]. Enclaves SGX hosted measured and signed software > entities, which are protected by asserting the outside memory accesses and > memory encryption. > > Add a two-layer macro system along with an encoding scheme to allow > wrappers to return trap numbers along ENCLS-specific error codes. The > bottom layer of the macro system splits between the leafs that return an > error code and those that do not. The second layer generates the correct > input/output annotations based on the number of operands for each leaf > function. > > [1] Intel SDM: 36.6 ENCLAVE INSTRUCTIONS AND INTELĀ® > > Signed-off-by: Jarkko Sakkinen This SOB needs to come... > Co-developed-by: Sean Christopherson > Signed-off-by: Sean Christopherson <--- ... here. > +/** > + * ENCLS_FAULT_FLAG - flag signifying an ENCLS return code is a trapnr > + * > + * ENCLS has its own (positive value) error codes and also generates > + * ENCLS specific #GP and #PF faults. And the ENCLS values get munged > + * with system error codes as everything percolates back up the stack. > + * Unfortunately (for us), we need to precisely identify each unique > + * error code, e.g. the action taken if EWB fails varies based on the > + * type of fault and on the exact SGX error code, i.e. we can't simply > + * convert all faults to -EFAULT. > + * > + * To make all three error types coexist, we set bit 30 to identify an > + * ENCLS fault. Bit 31 (technically bits N:31) is used to differentiate > + * between positive (faults and SGX error codes) and negative (system > + * error codes) values. > + */ > +#define ENCLS_FAULT_FLAG 0x40000000 BIT(30) > + > +/** > + * Retrieve the encoded trapnr from the specified return code. > + */ > +#define ENCLS_TRAPNR(r) ((r) & ~ENCLS_FAULT_FLAG) > + > +/* Issue a WARN() about an ENCLS leaf. */ > +#define ENCLS_WARN(r, name) { \ > + do { \ > + int _r = (r); \ > + WARN(_r, "sgx: %s returned %d (0x%x)\n", (name), _r, \ > + _r); \ Let that line stick out a bit: WARN(_r, "sgx: %s returned %d (0x%x)\n", (name), _r, _r); \ > + } while (0); \ > +} > + > +/** > + * encls_faulted() - Check if ENCLS leaf function faulted > + * @ret: the return value of an ENCLS leaf function call > + * > + * Return: true if the fault flag is set > + */ > +static inline bool encls_faulted(int ret) > +{ > + return (ret & ENCLS_FAULT_FLAG) != 0; return ret & ENCLS_FAULT_FLAG; -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette