From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <lersek@redhat.com>
Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by ml01.01.org (Postfix) with ESMTPS id C6AD481D72
 for <edk2-devel@ml01.01.org>; Thu, 10 Nov 2016 00:56:16 -0800 (PST)
Received: from int-mx13.intmail.prod.int.phx2.redhat.com
 (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by mx1.redhat.com (Postfix) with ESMTPS id 01827769F6;
 Thu, 10 Nov 2016 08:56:20 +0000 (UTC)
Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-106.phx2.redhat.com
 [10.3.116.106])
 by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id
 uAA8uITJ011461; Thu, 10 Nov 2016 03:56:19 -0500
To: Jeff Fan <jeff.fan@intel.com>, edk2-devel@ml01.01.org
References: <20161110060708.13932-1-jeff.fan@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
From: Laszlo Ersek <lersek@redhat.com>
Message-ID: <b17363c2-5da4-f162-20d6-fc9a0d8590f7@redhat.com>
Date: Thu, 10 Nov 2016 09:56:18 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101
 Thunderbird/45.4.0
MIME-Version: 1.0
In-Reply-To: <20161110060708.13932-1-jeff.fan@intel.com>
X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26
X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16
 (mx1.redhat.com [10.5.110.27]); Thu, 10 Nov 2016 08:56:20 +0000 (UTC)
Subject: Re: [PATCH 0/2] Put AP into safe hlt-loop code on S3 path
X-BeenThere: edk2-devel@lists.01.org
X-Mailman-Version: 2.1.21
Precedence: list
List-Id: EDK II Development  <edk2-devel.lists.01.org>
List-Unsubscribe: <https://lists.01.org/mailman/options/edk2-devel>,
 <mailto:edk2-devel-request@lists.01.org?subject=unsubscribe>
List-Archive: <http://lists.01.org/pipermail/edk2-devel/>
List-Post: <mailto:edk2-devel@lists.01.org>
List-Help: <mailto:edk2-devel-request@lists.01.org?subject=help>
List-Subscribe: <https://lists.01.org/mailman/listinfo/edk2-devel>,
 <mailto:edk2-devel-request@lists.01.org?subject=subscribe>
X-List-Received-Date: Thu, 10 Nov 2016 08:56:16 -0000
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit

On 11/10/16 07:07, Jeff Fan wrote:
> On S3 path, we will wake up APs to restore CPU context in PiSmmCpuDxeSmm
> driver. In case, one NMI or SMI happens, APs may exit from hlt state and
> execute the instruction after HLT instruction.
> 
> But APs are not running on safe code, it leads OVMF S3 boot unstable.
> 
> https://bugzilla.tianocore.org/show_bug.cgi?id=216
> 
> I tested real platform with 64bit DXE.
> 
> Jeff Fan (2):
>   UefiCpuPkg/PiSmmCpuDxeSmm: Put AP into safe hlt-loop code on S3 path
>   UefiCpuPkg/PiSmmCpuDxeSmm: Place AP to 32bit protected mode on S3 path
> 
>  UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c             | 31 ++++++++++++++
>  UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c | 25 ++++++++++++
>  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h    | 13 ++++++
>  UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c  | 59 +++++++++++++++++++++++++++
>  4 files changed, 128 insertions(+)
> 

Can we please append, to both commit messages:

Analyzed-by: Paolo Bonzini <pbonzini@redhat.com>

I think we should give credit to Paolo for his work in this thread.

I'll report back with test results (with my suggested rounding-down of
TopOfStack in patch #1).

Thanks
Laszlo