From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=209.132.183.28; helo=mx1.redhat.com; envelope-from=lersek@redhat.com; receiver=edk2-devel@lists.01.org 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 8E000211A43CD for ; Tue, 8 Jan 2019 07:38:25 -0800 (PST) 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 095F2811DD; Tue, 8 Jan 2019 15:38:25 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-197.rdu2.redhat.com [10.10.120.197]) by smtp.corp.redhat.com (Postfix) with ESMTP id 60A8019CB5; Tue, 8 Jan 2019 15:38:22 +0000 (UTC) To: Ard Biesheuvel , edk2-devel@lists.01.org Cc: Leif Lindholm , Michael D Kinney , Liming Gao , Jian J Wang , Hao Wu , Jagadeesh Ujja , Achin Gupta , Thomas Panakamattam Abraham , Sami Mujawar References: <20190103182825.32231-1-ard.biesheuvel@linaro.org> <20190103182825.32231-7-ard.biesheuvel@linaro.org> From: Laszlo Ersek Message-ID: <09818de2-2518-38f7-42ac-8882ecb2ea29@redhat.com> Date: Tue, 8 Jan 2019 16:38:21 +0100 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: <20190103182825.32231-7-ard.biesheuvel@linaro.org> 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]); Tue, 08 Jan 2019 15:38:25 +0000 (UTC) Subject: Re: [PATCH 5/6] MdeModulePkg/VariableRuntimeDxe: factor out boot service accesses X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Jan 2019 15:38:26 -0000 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 01/03/19 19:28, Ard Biesheuvel wrote: > In preparation of providing a standalone MM based variable runtime > driver, move the existing SMM driver to the new MM services table, > and factor out some pieces that are specific to the traditional > driver, mainly related to the use of UEFI boot services, which are > not accessible to standalone MM drivers. > > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ard Biesheuvel > --- > MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockSmm.c | 18 +--- > MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h | 50 +++++++++ > MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c | 59 ++++------ > MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf | 5 +- > MdeModulePkg/Universal/Variable/RuntimeDxe/VariableTraditionalMm.c | 114 ++++++++++++++++++++ > 5 files changed, 187 insertions(+), 59 deletions(-) I *vaguely* feel like we should extract the new functions to "PrivilegePolymorphic.h", rather than to "Variable.h". Please see initial commit 00663d047fc9 ("MdeModulePkg/Variable/RuntimeDxe: move SecureBootHook() decl to new header", 2017-10-10), and other commits that touched that file. I realize this is not a 100% "constructive" suggestion, and I feel appropriately bad about that. It's just that "Variable.h" has so many internals that I feel it's not a good dumping ground for these new functions. And the other header we have, looks closer in purpose. For example, MorLockInitAtEndOfDxe() is already declared in "PrivilegePolymorphic.h" (see commit f1304280435f, "MdeModulePkg/Variable/RuntimeDxe: introduce MorLockInitAtEndOfDxe() hook", 2017-10-10). Admittedly, now that we're going to have three separate builds of this driver, dedicating a separate header file to each "shared between A and B" relationship is getting a bit too complex. In retrospect, introducing "PrivilegePolymorphic.h" may not have been a "scalable" idea, after all, and I should have just dumped those functions all in "Variable.h". IOW, I think - targeting "Variable.h" now is inconsistent with earlier code, - extending "PrivilegePolymorphic.h" is also suboptimal (although still better than the previous option), - adding yet another header might be technically correct, but it would be over-engineering, - asking you to merge "PrivilegePolymorphic.h" back into "Variable.h" feels awkward, especially after I argued *for* "PrivilegePolymorphic.h" at length, when I originally introduced it. :/ Sigh. Can the variable driver maintainers comment please? (I still plan to regression-test this series, but I feel like I should force myself to at least skim the variable driver patches, beyond testing them. Because, next time I can't avoid working with this very complex driver, I wouldn't like to be *completely* lost.) Thanks, Laszlo