Re: [PATCH v15 15/23] x86/sgx: Add wrappers for ENCLS leaf functions

From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
	<x86@kernel.org>,
	Platform Driver <platform-driver-x86@vger.kernel.org>,
	linux-sgx@vger.kernel.org, Dave Hansen <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,
	mark.shanahan@intel.com,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	suresh.b.siddha@intel.com,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v15 15/23] x86/sgx: Add wrappers for ENCLS leaf functions
Date: Mon, 5 Nov 2018 19:30:38 +0200	[thread overview]
Message-ID: <20181105173038.GD4502@linux.intel.com> (raw)
Message-ID: <20181105173038.SO3PE6PTYlLi-Gj52kJ9TcKM_E43vtVCnrMg7GRXYng@z> (raw)
In-Reply-To: <CAHp75VdhSwy8zzf64PZnHhZVikJEzasu-=a+UOz4cLAxEJW-YA@mail.gmail.com>

On Sat, Nov 03, 2018 at 03:17:35PM +0200, Andy Shevchenko wrote:
> On Sat, Nov 3, 2018 at 1:18 AM Jarkko Sakkinen
> <jarkko.sakkinen@linux.intel.com> 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.

/Jarkko