From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH v15 15/23] x86/sgx: Add wrappers for ENCLS leaf functions Date: Tue, 6 Nov 2018 14:03:41 +0200 Message-ID: <20181106120341.GA11465@linux.intel.com> References: <20181102231320.29164-1-jarkko.sakkinen@linux.intel.com> <20181102231320.29164-16-jarkko.sakkinen@linux.intel.com> <20181105173038.GD4502@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Andy Shevchenko Cc: "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Platform Driver , linux-sgx@vger.kernel.org, Dave Hansen , sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, mark.shanahan@intel.com, Andy Shevchenko , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , suresh.b.siddha@intel.com, Linux Kernel Mailing List List-Id: platform-driver-x86.vger.kernel.org On Mon, Nov 05, 2018 at 10:39:46PM +0200, Andy Shevchenko wrote: > On Mon, Nov 5, 2018 at 7:30 PM Jarkko Sakkinen > wrote: > > > > On Sat, Nov 03, 2018 at 03:17:35PM +0200, Andy Shevchenko wrote: > > > On Sat, Nov 3, 2018 at 1:18 AM Jarkko Sakkinen > > > wrote: > > > > > > > > ENCLS is an umbrella instruction for a variety of cpl0 SGX functions. > > > > The ENCLS function that is executed is specified in EAX, with each > > > > function potentially having more leaf-specific operands beyond EAX. > > > > ENCLS introduces its own (positive value) error codes that (some) > > > > leafs use to return failure information in EAX. Leafs that return > > > > an error code also modify RFLAGS. And finally, ENCLS generates > > > > ENCLS-specific non-fatal #GPs and #PFs, i.e. a bug-free kernel may > > > > encounter faults on ENCLS that must be handled gracefully. > > > > > > > > Because of the complexity involved in encoding ENCLS and handling its > > > > assortment of failure paths, executing any given leaf is not a simple > > > > matter of emitting ENCLS. > > > > > > > > To enable adding support for ENCLS leafs with minimal fuss, 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. > > > > > > > +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */ > > > > > > > +/** > > > > > > I dunno if kernel-doc script still complains about this. > > > > Is there a way to ask for make htmldocs to do only a subset of docs? > > Still kind of trying to figure out what would be a good flow for > > working with Sphinx. > > What I'm telling here is about Copyright notice, which in my > understanding is not a part of kernel-doc formatting. Though I might > be mistaken. > I remember some USB code has that and I saw a warning. > > -- > With Best Regards, > Andy Shevchenko I'll remove it because I don't find it in other headers under arch/x86. /Jarkko