From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=iuVh=YD=vger.kernel.org=linux-sgx-owner@kernel.org>
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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,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 CA6C8C47404
	for <linux-sgx@archiver.kernel.org>; Thu, 10 Oct 2019 00:21:17 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.kernel.org (Postfix) with ESMTP id A760221848
	for <linux-sgx@archiver.kernel.org>; Thu, 10 Oct 2019 00:21:17 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1731589AbfJJAVR (ORCPT <rfc822;linux-sgx@archiver.kernel.org>);
        Wed, 9 Oct 2019 20:21:17 -0400
Received: from mga01.intel.com ([192.55.52.88]:53359 "EHLO mga01.intel.com"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1731230AbfJJAVR (ORCPT <rfc822;linux-sgx@vger.kernel.org>);
        Wed, 9 Oct 2019 20:21:17 -0400
X-Amp-Result: UNKNOWN
X-Amp-Original-Verdict: FILE UNKNOWN
X-Amp-File-Uploaded: False
Received: from fmsmga005.fm.intel.com ([10.253.24.32])
  by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Oct 2019 17:21:16 -0700
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.67,278,1566889200"; 
   d="scan'208";a="393858404"
Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.41])
  by fmsmga005.fm.intel.com with ESMTP; 09 Oct 2019 17:21:16 -0700
Date:   Wed, 9 Oct 2019 17:21:16 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     "Xing, Cedric" <cedric.xing@intel.com>
Cc:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        linux-sgx@vger.kernel.org
Subject: Re: [PATCH for_v23 16/16] x86/vdso: sgx: Rework
 __vdso_sgx_enter_enclave() to prefer "no callback"
Message-ID: <20191010002116.GB12533@linux.intel.com>
References: <20191008044613.12350-1-sean.j.christopherson@intel.com>
 <20191008044613.12350-17-sean.j.christopherson@intel.com>
 <15c03e7e-cd98-5ea2-82a1-a11bec4abe2a@intel.com>
 <20191009191003.GD19952@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20191009191003.GD19952@linux.intel.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-sgx-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-sgx.vger.kernel.org>
X-Mailing-List: linux-sgx@vger.kernel.org

On Wed, Oct 09, 2019 at 12:10:03PM -0700, Sean Christopherson wrote:
> > >+
> > >+	/* Clear RFLAGS.DF per x86_64 ABI */
> > >+	cld
> > >+
> > >+	/* Load the callback pointer to %rax and invoke it via retpoline. */
> > >+	mov	0x20(%rbp), %rax
> > 
> > Per X86_64 ABI, %rsp shall be 16 bytes aligned before "call". But %rsp here
> > doesn't look aligned properly.
> 
> Argh, I probably botched it back in patch 02/16 too.  I'll see if I can
> add a check to verify %rsp alignment in the selftest, verifying via code
> inspection is bound to be error prone.

Added a selftest, stack is indeed not properly aligned.