From mboxrd@z Thu Jan  1 00:00:00 1970
Authentication-Results: mx.groups.io;
 dkim=missing; spf=pass (domain: redhat.com, ip: 209.132.183.28, mailfrom: lersek@redhat.com)
Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28])
 by groups.io with SMTP; Fri, 26 Jul 2019 03:38:32 -0700
Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11])
	(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
	(No client certificate requested)
	by mx1.redhat.com (Postfix) with ESMTPS id 98F9583F4C;
	Fri, 26 Jul 2019 10:38:31 +0000 (UTC)
Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-40.ams2.redhat.com [10.36.116.40])
	by smtp.corp.redhat.com (Postfix) with ESMTP id 74C8F600C4;
	Fri, 26 Jul 2019 10:38:30 +0000 (UTC)
Subject: Re: [edk2-devel] [Patch v3 6/6] UefiCpuPkg/RegisterCpuFeaturesLib: Start all processors simultaneously.
To: devel@edk2.groups.io, eric.dong@intel.com
Cc: Ray Ni <ray.ni@intel.com>, Chandana Kumar <chandana.c.kumar@intel.com>,
 Star Zeng <star.zeng@intel.com>
References: <20190724070727.14976-1-eric.dong@intel.com>
 <20190724070727.14976-7-eric.dong@intel.com>
From: "Laszlo Ersek" <lersek@redhat.com>
Message-ID: <f3484f29-fe6c-50cb-b66a-782775920d54@redhat.com>
Date: Fri, 26 Jul 2019 12:38:29 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.9.1
MIME-Version: 1.0
In-Reply-To: <20190724070727.14976-7-eric.dong@intel.com>
X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11
X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Fri, 26 Jul 2019 10:38:31 +0000 (UTC)
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit

On 07/24/19 09:07, Dong, Eric wrote:
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1973
> 
> For semaphore type register, it required all processors to do the
> task at the same time.
> Current logic begins BSP's task after all APs have finished their tasks.
> This will caused set semaphore task hang if semaphore has package
> level type.
> This patch use new EDKII_PEI_MP_SERVICES2_PPI to start all processors at
> the same time to fix the potential hang issue.
> 
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Chandana Kumar <chandana.c.kumar@intel.com>
> Cc: Star Zeng <star.zeng@intel.com>
> Signed-off-by: Eric Dong <eric.dong@intel.com>
> ---
>  .../CpuFeaturesInitialize.c                   |  2 +-
>  .../DxeRegisterCpuFeaturesLib.c               |  6 +-
>  .../PeiRegisterCpuFeaturesLib.c               | 66 ++++++++++++++-----
>  .../PeiRegisterCpuFeaturesLib.inf             |  1 +
>  .../RegisterCpuFeatures.h                     |  2 +-
>  5 files changed, 54 insertions(+), 23 deletions(-)

My testing did not cover this patch.

Thanks
Laszlo