From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by spool.mail.gandi.net (Postfix) with ESMTPS id C31847803E3 for ; Fri, 1 Mar 2024 07:44:17 +0000 (UTC) DKIM-Signature: a=rsa-sha256; bh=DYyDiG+IsR6kG+KldWbpC2e5jkPbwUKyO0COdchaHXI=; c=relaxed/simple; d=groups.io; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References:MIME-Version:Precedence:List-Subscribe:List-Help:Sender:List-Id:Mailing-List:Delivered-To:Reply-To:List-Unsubscribe-Post:List-Unsubscribe:Content-Transfer-Encoding:Content-Type; s=20140610; t=1709279056; v=1; b=KMztL3vnGNcHh1pQSm/o7aBboDVUeWCv+1z9bb629O7UxXwzmtNQ5YmS9oFYNvAxoOe27tV6 djxbN4/Nte0cD7opi+95Idpe8MbW2uCtvcNGLE2bCdp7Ehysl4wNXVzUG/G2JeWhI8z0CCrgNYn Iuf5TeqOPHD/mAyCw6uFtJAA= X-Received: by 127.0.0.2 with SMTP id H37kYY7687511x060lLn8VYi; Thu, 29 Feb 2024 23:44:16 -0800 X-Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mx.groups.io with SMTP id smtpd.web11.17787.1709279055569551574 for ; Thu, 29 Feb 2024 23:44:15 -0800 X-Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-213-lQsQziFHPya7MPVA9m2_tg-1; Fri, 01 Mar 2024 02:44:11 -0500 X-MC-Unique: lQsQziFHPya7MPVA9m2_tg-1 X-Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 16964800074; Fri, 1 Mar 2024 07:44:11 +0000 (UTC) X-Received: from sirius.home.kraxel.org (unknown [10.39.192.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A500D8CED; Fri, 1 Mar 2024 07:44:10 +0000 (UTC) X-Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id EBEFA18014A4; Fri, 1 Mar 2024 08:44:02 +0100 (CET) From: "Gerd Hoffmann" To: devel@edk2.groups.io Cc: Jiewen Yao , Oliver Steffen , Laszlo Ersek , Michael Roth , Erdem Aktas , Gerd Hoffmann , Min Xu , Ard Biesheuvel , Tom Lendacky Subject: [edk2-devel] [PATCH v2 09/10] OvmfPkg/ResetVector: leave SEV VC handler installed longer Date: Fri, 1 Mar 2024 08:44:01 +0100 Message-ID: <20240301074402.98625-10-kraxel@redhat.com> In-Reply-To: <20240301074402.98625-1-kraxel@redhat.com> References: <20240301074402.98625-1-kraxel@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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 Reply-To: devel@edk2.groups.io,kraxel@redhat.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: KLqzshSFxUOog9eWwCkXAMxYx7686176AA= Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-GND-Status: LEGIT Authentication-Results: spool.mail.gandi.net; dkim=pass header.d=groups.io header.s=20140610 header.b=KMztL3vn; dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=redhat.com (policy=none); spf=pass (spool.mail.gandi.net: domain of bounce@groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce@groups.io When running in SEV mode keep the VC handler installed. Add a function to uninstall it later. This allows using the cpuid instruction in SetCr3ForPageTables64, which is needed to check for la57 & 1G page support. Signed-off-by: Gerd Hoffmann --- OvmfPkg/ResetVector/Ia32/AmdSev.asm | 12 ++++++++++-- OvmfPkg/ResetVector/Ia32/PageTables64.asm | 1 + OvmfPkg/ResetVector/Main.asm | 4 ++++ 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/OvmfPkg/ResetVector/Ia32/AmdSev.asm b/OvmfPkg/ResetVector/Ia32/AmdSev.asm index 23e4c5ebbe92..cbb86871636f 100644 --- a/OvmfPkg/ResetVector/Ia32/AmdSev.asm +++ b/OvmfPkg/ResetVector/Ia32/AmdSev.asm @@ -320,9 +320,9 @@ NoSevEsVcHlt: NoSevPass: xor eax, eax -SevExit: ; - ; Clear exception handlers and stack + ; When NOT running in SEV mode: clear exception handlers and stack here. + ; Otherwise: SevClearVcHandlerAndStack must be called later. ; push eax mov eax, ADDR_OF(IdtrClear) @@ -330,8 +330,16 @@ SevExit: pop eax mov esp, 0 +SevExit: OneTimeCallRet CheckSevFeatures +SevClearVcHandlerAndStack: + ; Clear exception handlers and stack + mov eax, ADDR_OF(IdtrClear) + lidt [cs:eax] + mov esp, 0 + OneTimeCallRet SevClearVcHandlerAndStack + ; Start of #VC exception handling routines ; diff --git a/OvmfPkg/ResetVector/Ia32/PageTables64.asm b/OvmfPkg/ResetVector/Ia32/PageTables64.asm index b922c845f297..29ce155eed8d 100644 --- a/OvmfPkg/ResetVector/Ia32/PageTables64.asm +++ b/OvmfPkg/ResetVector/Ia32/PageTables64.asm @@ -254,6 +254,7 @@ SevInit: CreatePageTables4Level edx ; Clear the C-bit from the GHCB page if the SEV-ES is enabled. OneTimeCall SevClearPageEncMaskForGhcbPage + OneTimeCall SevClearVcHandlerAndStack jmp SetCr3 TdxBspInit: diff --git a/OvmfPkg/ResetVector/Main.asm b/OvmfPkg/ResetVector/Main.asm index 46cfa87c4c0a..88b25db3bc9e 100644 --- a/OvmfPkg/ResetVector/Main.asm +++ b/OvmfPkg/ResetVector/Main.asm @@ -80,7 +80,11 @@ SearchBfv: ; Set the OVMF/SEV work area as appropriate. ; OneTimeCall CheckSevFeatures + cmp byte[WORK_AREA_GUEST_TYPE], 1 + jnz NoSevIa32 + OneTimeCall SevClearVcHandlerAndStack +NoSevIa32: ; ; Restore initial EAX value into the EAX register ; -- 2.44.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#116221): https://edk2.groups.io/g/devel/message/116221 Mute This Topic: https://groups.io/mt/104660115/7686176 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io] -=-=-=-=-=-=-=-=-=-=-=-