From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail05.groups.io (mail05.groups.io [45.79.224.7]) by spool.mail.gandi.net (Postfix) with ESMTPS id 09CC07803D1 for ; Fri, 3 May 2024 13:56:26 +0000 (UTC) DKIM-Signature: a=rsa-sha256; bh=ICw7VYMH9Z9fAbntgNlRN/5T0H0nryuPDYlKvMskO2s=; c=relaxed/simple; d=groups.io; h=DKIM-Filter:Message-ID:Date:MIME-Version:User-Agent:Subject:To:Cc:References:From:In-Reply-To:Precedence:List-Subscribe:List-Help:Sender:List-Id:Mailing-List:Delivered-To:Resent-Date:Resent-From:Reply-To:List-Unsubscribe-Post:List-Unsubscribe:Content-Language:Content-Type:Content-Transfer-Encoding; s=20240206; t=1714744585; v=1; b=FseQF0NdRolLOY0u+3DpM9iVpmwlqCgR2xl4fpxhlvrZ6NauUWpqrwmoEBG86pZ+/ynsMYVI nZWu68HMa9iyoyk5uq7cVUdojlgVq5i7Jkul/+ltaUrGp35ySTSDJ1Q7svub7VYKuyNGeb5NvEL jBb4byaoX/7t3me7SyMm2y2t8cFkmFQp7WCpObq4rKoCvWr+tQIpe1+1mPiV8A3R7Px2EawkTsE g829KUgjfOY1oiuYdD9pfaSYr8hbxAr15E2FgIY6ylwNiinQCVawGNhfksOuqm2VqMvErDZ9AT4 nR0mE+yiszkMmjwEnXxRk26wHZp8yn1GGqIBm4fo+xCMQ== X-Received: by 127.0.0.2 with SMTP id OZsWYY7687511x8mx3yaxqsJ; Fri, 03 May 2024 06:56:25 -0700 X-Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mx.groups.io with SMTP id smtpd.web10.13320.1714744584946554009 for ; Fri, 03 May 2024 06:56:25 -0700 X-Received: from [10.137.194.171] (unknown [131.107.159.43]) by linux.microsoft.com (Postfix) with ESMTPSA id 644B720B2C80; Fri, 3 May 2024 06:56:24 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 644B720B2C80 Message-ID: Date: Fri, 3 May 2024 06:56:24 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [edk2-devel] [PATCH v1 1/1] StandaloneMmPkg/StandaloneMmHobLib: Remove HOB creation To: devel@edk2.groups.io, nhi@os.amperecomputing.com, nhiphambka@gmail.com Cc: Ard Biesheuvel , Ray Ni , Sami Mujawar , Kun Qin References: <20231205134757.14692-1-nhiphambka@gmail.com> <0d99c3c9-9dd0-494a-93b1-e9270914162b@linux.microsoft.com> From: "Oliver Smith-Denny" In-Reply-To: Precedence: Bulk List-Subscribe: List-Help: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Resent-Date: Fri, 03 May 2024 06:56:25 -0700 Resent-From: osde@linux.microsoft.com Reply-To: devel@edk2.groups.io,osde@linux.microsoft.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: XItTEQgR3O3v7B5fp7kcXFHXx7686176AA= Content-Language: en-CA Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-GND-Status: LEGIT Authentication-Results: spool.mail.gandi.net; dkim=pass header.d=groups.io header.s=20240206 header.b=FseQF0Nd; dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=linux.microsoft.com (policy=none); spf=pass (spool.mail.gandi.net: domain of bounce@groups.io designates 45.79.224.7 as permitted sender) smtp.mailfrom=bounce@groups.io On 5/2/2024 7:28 PM, Nhi Pham via groups.io wrote: > On 5/2/2024 4:31 AM, Oliver Smith-Denny via groups.io wrote: >> Hi folks, returning to this thread because I noticed that HOB >> creation still exists in StandaloneMmCore for ARM: >> >> https://github.com/tianocore/edk2/blob/5d4c5253e8bbc0baa8837fcd868925212= df85201/StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/Arm/CreateHobLis= t.c >> >> As far as I can tell, there is only this one file that creates 6 >> HOBs from StandaloneMmCore. Per our earlier discussion that led to >> disabling HOB creation in StandaloneMm, I think that this falls into >> the case where StandaloneMm is a HOB consumer phase, not a producer >> phase and so it should not be creating these HOBs. On the x64 side, >> all of the StandaloneMm HOB creation functions ASSERT with the >> comment that StandaloneMm is a HOB consumer phase and should not >> be creating HOBs. >=20 > The HOB creation in StandaloneMmCoreEntryPoint is exclusively consumed=20 > by the MM_CORE_STANDALONE module=20 > (StandaloneMmPkg/Core/StandaloneMmCore.inf), not a MM_STANDALONE module.= =20 > Per my understanding earlier, the MM_CORE_STANDALONE is a producer and=20 > other MM_STANDALONE modules are consumers. So we removed the HOB=20 > creation in the StandaloneMmHobLib which is consumed by MM_STANDALONE=20 > modules. >=20 > Also, we still retain the HOB creation in the=20 > StandaloneMmPkg/Library/StandaloneMmCoreHobLib library instance. >=20 The PI spec is light on details on HOBs in Standalone MM, but it is clear that there are HOB producer phases and HOB consumer phases. Pre-Standalone MM, the HOB producer phase was PEI and the HOB consumer phase was DXE/SMM. In the Standalone MM world, it still follows that a boot phase is either a HOB consumer or a HOB producer. Currently, Standalone MM is both, regardless that it is the core that is producing the HOBs. I think that Levi's work to remove HOB creation in Standalone MM and move it to TF-A is the right move here. Thanks, Oliver -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#118556): https://edk2.groups.io/g/devel/message/118556 Mute This Topic: https://groups.io/mt/103018869/7686176 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io] -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-