From nobody Mon Feb 9 12:10:06 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) client-ip=66.175.222.108; envelope-from=bounce+27952+111519+1787277+3901457@groups.io; helo=mail02.groups.io; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+111519+1787277+3901457@groups.io; dmarc=fail(p=none dis=none) header.from=intel.com ARC-Seal: i=1; a=rsa-sha256; t=1700550182; cv=none; d=zohomail.com; s=zohoarc; b=afLtFLkGDiG/VdOjUC7UZy6LdkZM8lK0F9nEJevM1oiTA3DUJwCIVsLDP+BQP2EELDn9sBAK3SlvKgZ14w7sM+M1ZRlelB7JmDA6txV05Na6Vt+s0zqIQqXLY4Q9zYLzRZE27JgB/CwwBF2XxF7DgiXUvU33wEG0B4KRLg4xEw8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1700550182; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Reply-To:Reply-To:References:Sender:Subject:Subject:To:To:Message-Id; bh=OGAohxBRXErP78LINxaHp0JKKHvzHfhRx94QmuhIVn8=; b=C/135vcXHVlv1DEZAQv3XNNfJE1ZvZylwpdKLOHdLDh1rd6PVdXeYACQi7QtjMMoLiIW9dV4/XsciOHMO6n5Za2gMWAAhDayVMxVSsNS4iP+nzUa2mj8EmbW19U8A+L9Qpvs8RuZadU9pOHIBW7I5thucT24sUym4KIziD2vpYA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+111519+1787277+3901457@groups.io; dmarc=fail header.from= (p=none dis=none) Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by mx.zohomail.com with SMTPS id 1700550182095405.2981216520318; Mon, 20 Nov 2023 23:03:02 -0800 (PST) Return-Path: DKIM-Signature: a=rsa-sha256; bh=ADLlj5TIR7nuQP9U2gmXEzgSbUT1V7Dr01jnT9eoBcw=; 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; s=20140610; t=1700550181; v=1; b=JMFQbODQSTMiiRd365VLhjTQogyVZpduCDVW9Z7RFENxBt/7qvKwDnIoTrnd7+9jyc6ASo4Z 691rR8LzoAliCmjkVoTYNNDlGM92b25ZiuTF9tx1YalbsW4YIFY/YzMTNBO7uR0sUgmLHJu0DIg ZTVSL4WUJqBGU7AIkwjh7s4M= X-Received: by 127.0.0.2 with SMTP id DGdqYY1788612x2hMQDdg8k6; Mon, 20 Nov 2023 23:03:01 -0800 X-Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) by mx.groups.io with SMTP id smtpd.web10.30512.1700550170171771930 for ; Mon, 20 Nov 2023 23:03:01 -0800 X-IronPort-AV: E=McAfee;i="6600,9927,10900"; a="390633424" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="390633424" X-Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Nov 2023 23:03:00 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10900"; a="795704989" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="795704989" X-Received: from shwdesssddpdwei.ccr.corp.intel.com ([10.239.157.28]) by orsmga008.jf.intel.com with ESMTP; 20 Nov 2023 23:02:58 -0800 From: "Sheng Wei" To: devel@edk2.groups.io Cc: Eric Dong , Ray Ni , Laszlo Ersek , Wu Jiaxin , Tan Dun Subject: [edk2-devel] [PATCH v6 5/6] UefiCpuPkg: Backup and Restore MSR IA32_U_CET in SMI handler. Date: Tue, 21 Nov 2023 15:02:45 +0800 Message-Id: <20231121070246.505-6-w.sheng@intel.com> In-Reply-To: <20231121070246.505-1-w.sheng@intel.com> References: <20231121070246.505-1-w.sheng@intel.com> MIME-Version: 1.0 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,w.sheng@intel.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: pk6xUgefFGCRp0ISXfHgmu9Gx1787277AA= Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @groups.io) X-ZM-MESSAGEID: 1700550182926100007 Content-Type: text/plain; charset="utf-8" OS may enable CET-IBT feature by set MSR IA32_U_CET.bit2. If IA32_U_CET.bit2 is set, CPU is in WAIT_FOR_ENDBRANCH state and the next assemble code is not ENDBR, it will trigger #CP exception when set CR4.CET bit. SMI handler needs to backup MSR IA32_U_CET and clear MSR IA32_U_CET before set CR4.CET bit, And SMI handler needs to restore MSR IA32_U_CET when exit SMI handler. Signed-off-by: Sheng Wei Cc: Eric Dong Cc: Ray Ni Cc: Laszlo Ersek Cc: Wu Jiaxin Cc: Tan Dun Reviewed-by: Laszlo Ersek Reviewed-by: Ray Ni --- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm | 15 +++++++++++++++ UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm | 15 +++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm b/UefiCpuPkg/PiSm= mCpuDxeSmm/Ia32/SmiEntry.nasm index 1da9afab97..9e1155dee6 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm @@ -202,11 +202,21 @@ ASM_PFX(mPatchCetSupported): push edx push eax =20 + mov ecx, MSR_IA32_U_CET + rdmsr + push edx + push eax + mov ecx, MSR_IA32_PL0_SSP rdmsr push edx push eax =20 + mov ecx, MSR_IA32_U_CET + xor eax, eax + xor edx, edx + wrmsr + mov ecx, MSR_IA32_S_CET mov eax, MSR_IA32_CET_SH_STK_EN xor edx, edx @@ -276,6 +286,11 @@ CetDone: pop edx wrmsr =20 + mov ecx, MSR_IA32_U_CET + pop eax + pop edx + wrmsr + mov ecx, MSR_IA32_S_CET pop eax pop edx diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm b/UefiCpuPkg/PiSmm= CpuDxeSmm/X64/SmiEntry.nasm index abf9f1a90a..881d3177f7 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm @@ -217,6 +217,11 @@ ASM_PFX(mPatchCetSupported): push rdx push rax =20 + mov ecx, MSR_IA32_U_CET + rdmsr + push rdx + push rax + mov ecx, MSR_IA32_PL0_SSP rdmsr push rdx @@ -227,6 +232,11 @@ ASM_PFX(mPatchCetSupported): push rdx push rax =20 + mov ecx, MSR_IA32_U_CET + xor eax, eax + xor edx, edx + wrmsr + mov ecx, MSR_IA32_S_CET mov eax, MSR_IA32_CET_SH_STK_EN xor edx, edx @@ -325,6 +335,11 @@ mCetSupportedAbsAddr: pop rdx wrmsr =20 + mov ecx, MSR_IA32_U_CET + pop rax + pop rdx + wrmsr + mov ecx, MSR_IA32_S_CET pop rax pop rdx --=20 2.26.2.windows.1 -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. 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