From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from nwk-aaemail-lapp02.apple.com (nwk-aaemail-lapp02.apple.com [17.151.62.67]) by mx.groups.io with SMTP id smtpd.web11.1442.1581356347810117747 for ; Mon, 10 Feb 2020 09:39:08 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@apple.com header.s=20180706 header.b=L5r1cNnY; spf=pass (domain: apple.com, ip: 17.151.62.67, mailfrom: afish@apple.com) Received: from pps.filterd (nwk-aaemail-lapp02.apple.com [127.0.0.1]) by nwk-aaemail-lapp02.apple.com (8.16.0.27/8.16.0.27) with SMTP id 01AHRkvl033378 for ; Mon, 10 Feb 2020 09:39:06 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=apple.com; h=sender : from : content-type : content-transfer-encoding : mime-version : subject : message-id : date : to; s=20180706; bh=q33SoB/N15J0mRmWuHVaiUTVXbTLpN12POecM5+m8vI=; b=L5r1cNnYzPWERUQ260w7SfHMt9a5aXDrioo6d+zkE0zXF/0+pwYxvKdKI3g/oZHnfb7p dkr7+YhMDhhfqgf50vTTpaUtCH0AGW7aB53c+8Ni1JVzfzz5pSNaqkWzo4TfjO1qQ76m pGQ4Nd/4VnSphaRpK0xqbFjsldbrJm9wcM9H0/Jf5ITD0Uic7bZGy3vTgURX8PUqWU3K B8iy/RClDUEb2Krjhd3juaByLcvMamuCjpijtufoc9Zro0b591Papk3xwyITAw1fu6l1 BjT9RvnugKnqWdSoJGHcbuOSR1qGFQxf+qHOfz4bhu+8gbL5pc6Izn/D6ITgkiu1oXqO 7g== Received: from rn-mailsvcp-mta-lapp03.rno.apple.com (rn-mailsvcp-mta-lapp03.rno.apple.com [10.225.203.151]) by nwk-aaemail-lapp02.apple.com with ESMTP id 2y1tenrgbh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO) for ; Mon, 10 Feb 2020 09:39:06 -0800 Received: from rn-mailsvcp-mmp-lapp04.rno.apple.com (rn-mailsvcp-mmp-lapp04.rno.apple.com [17.179.253.17]) by rn-mailsvcp-mta-lapp03.rno.apple.com (Oracle Communications Messaging Server 8.1.0.1.20190704 64bit (built Jul 4 2019)) with ESMTPS id <0Q5H0029ZYD5O5C0@rn-mailsvcp-mta-lapp03.rno.apple.com> for devel@edk2.groups.io; Mon, 10 Feb 2020 09:39:05 -0800 (PST) Received: from process_milters-daemon.rn-mailsvcp-mmp-lapp04.rno.apple.com by rn-mailsvcp-mmp-lapp04.rno.apple.com (Oracle Communications Messaging Server 8.1.0.1.20190704 64bit (built Jul 4 2019)) id <0Q5H00B00XUOPT00@rn-mailsvcp-mmp-lapp04.rno.apple.com> for devel@edk2.groups.io; Mon, 10 Feb 2020 09:39:05 -0800 (PST) X-Va-A: X-Va-T-CD: af33feddfb7fcbdf4ba2524fa1b83a2c X-Va-E-CD: 894be3b6b7792010cb25f75e5439e51d X-Va-R-CD: 9f516bdfde8686d72718a43120b7b108 X-Va-CD: 0 X-Va-ID: 7ba5a94a-7ef8-4108-b3db-859a01415e20 X-V-A: X-V-T-CD: af33feddfb7fcbdf4ba2524fa1b83a2c X-V-E-CD: 894be3b6b7792010cb25f75e5439e51d X-V-R-CD: 9f516bdfde8686d72718a43120b7b108 X-V-CD: 0 X-V-ID: 6fa081b3-6d2a-4c80-bc4d-aa1053821859 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-10_06:2020-02-10,2020-02-10 signatures=0 Received: from [17.235.8.241] by rn-mailsvcp-mmp-lapp04.rno.apple.com (Oracle Communications Messaging Server 8.1.0.1.20190704 64bit (built Jul 4 2019)) with ESMTPSA id <0Q5H00VQ1YD4AU20@rn-mailsvcp-mmp-lapp04.rno.apple.com> for devel@edk2.groups.io; Mon, 10 Feb 2020 09:39:05 -0800 (PST) Sender: afish@apple.com From: "Andrew Fish" MIME-version: 1.0 (Mac OS X Mail 13.0 \(3594.4.17\)) Subject: PCD Migration issue Message-id: <6D19BFCB-B1F3-415E-9DDA-23992E98B637@apple.com> Date: Mon, 10 Feb 2020 09:39:03 -0800 To: devel@edk2.groups.io X-Mailer: Apple Mail (2.3594.4.17) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2020-02-10_06:,, signatures=0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: quoted-printable We recently hit an issue when updating our UDK version in our common = code base. Our recovery update path started failing for older platforms = since the PEI was the old UDK version and the DXE from the Capsule was = the new UDK version. Basically the version of the PCD changed. It looks = like there are some checks, but the seem to be more about making sure = the build systems matches the code vs. dealing with an update case like = we hit.=20 It does not look like the PCD database is designed to deal with this. We = are fixing this by extracting the PEI PCD database from the capsule and = then having some platform specific code to patch any PCD entries that = got set in PEI that are needed by DXE.=20 In the future it would be helpful if the PCD database would change in = some what of a backward compatible way, and have the headers needed to = parse the old and new version.=20 It also seems like adding a Dynamic PCD could potentially change the = token layout and thus break compatibility? Is there any scheme to keep a = previous token layout?=20 Thanks, Andrew Fish=