From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by mx.groups.io with SMTP id smtpd.web10.5526.1582707376064891365 for ; Wed, 26 Feb 2020 00:56:16 -0800 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: intel.com, ip: 192.55.52.88, mailfrom: liming.gao@intel.com) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Feb 2020 00:56:15 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,487,1574150400"; d="scan'208";a="256247153" Received: from fmsmsx106.amr.corp.intel.com ([10.18.124.204]) by orsmga002.jf.intel.com with ESMTP; 26 Feb 2020 00:56:14 -0800 Received: from shsmsx601.ccr.corp.intel.com (10.109.6.141) by FMSMSX106.amr.corp.intel.com (10.18.124.204) with Microsoft SMTP Server (TLS) id 14.3.439.0; Wed, 26 Feb 2020 00:56:14 -0800 Received: from shsmsx606.ccr.corp.intel.com (10.109.6.216) by SHSMSX601.ccr.corp.intel.com (10.109.6.141) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Wed, 26 Feb 2020 16:56:12 +0800 Received: from shsmsx606.ccr.corp.intel.com ([10.109.6.216]) by SHSMSX606.ccr.corp.intel.com ([10.109.6.216]) with mapi id 15.01.1713.004; Wed, 26 Feb 2020 16:56:12 +0800 From: "Liming Gao" To: "devel@edk2.groups.io" , "Ni, Ray" , Laszlo Ersek , "leo.duran@amd.com" , "Wu, Hao A" , "Fu, Siyuan" CC: "Dong, Eric" , "leif@nuviainc.com" , "Kinney, Michael D" , "afish@apple.com" , "Gao, Liming" Subject: Re: [edk2-devel] [PATCH 0/2] UefiCpuPkg/Library: Fix bug in MpInitLib Thread-Topic: [edk2-devel] [PATCH 0/2] UefiCpuPkg/Library: Fix bug in MpInitLib Thread-Index: AQHV7B0sTUgS6gAtT0OX4rRSWd18rqgsIFiAgAB2EICAAI0S4A== Date: Wed, 26 Feb 2020 08:56:12 +0000 Message-ID: <58ccd1485c0a409691e542247699fe58@intel.com> References: <1582659566-9893-1-git-send-email-leo.duran@amd.com> <734D49CCEBEEF84792F5B80ED585239D5C4542DA@SHSMSX104.ccr.corp.intel.com> In-Reply-To: <734D49CCEBEEF84792F5B80ED585239D5C4542DA@SHSMSX104.ccr.corp.intel.com> Accept-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-version: 11.2.0.6 dlp-product: dlpe-windows dlp-reaction: no-action x-originating-ip: [10.239.127.36] MIME-Version: 1.0 Return-Path: liming.gao@intel.com Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Leo: Now, we enter into Hard Feature Freeze phase until edk2-stable202002 tag= is created at 2020-02-28. Only critical bug fix is still allowed. Do you request to catch this fix into this stable tag? If yes, please wo= rk closely with UefiCpuPkg maintainers to catch the stable tag release sche= dule 2020-02-28. Thanks Liming > -----Original Message----- > From: devel@edk2.groups.io On Behalf Of Ni, Ray > Sent: Wednesday, February 26, 2020 3:57 PM > To: Laszlo Ersek ; devel@edk2.groups.io; leo.duran@am= d.com; Wu, Hao A ; Fu, Siyuan > > Cc: Dong, Eric > Subject: Re: [edk2-devel] [PATCH 0/2] UefiCpuPkg/Library: Fix bug in MpI= nitLib >=20 > Leo, >=20 > > > BTW, reading the PlatformId MSR was already being done by MicrocodeD= etect(), > > > but it never affected AMD-based platforms as the flow never gets tha= t far, since > > > the Detect routine bails out early when it finds the size of the pat= ch is zero. >=20 > You are saying that PlatformId MSR access is not performed by CPU in old= code because of the zero size uCode. > But now with Hao or Siyuan's change, the PlatformId MSR access is always= performed even when there is no uCode. It sounds like a > regression to optimization to me. > Did you evaluate the path to avoid accessing PlatformID MSR when uCode d= oesn't exist? So that the API to detect AMD processor is not > needed at all. >=20 > Thanks, > Ray >=20 >=20