From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F69FEB64DC for ; Wed, 19 Jul 2023 03:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230253AbjGSDGZ (ORCPT ); Tue, 18 Jul 2023 23:06:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229731AbjGSDGU (ORCPT ); Tue, 18 Jul 2023 23:06:20 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BBB61BCF; Tue, 18 Jul 2023 20:06:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1689735979; x=1721271979; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=+Z0zqG7VipzZjKGonsZ4TWL6em48rDUeDmL5b7Oaqdk=; b=h+SILe6TzxPocRWTvY/mx1GlHztCBRbrJIwe+09gvRxrs6so2F2JLQve Y4sGqMg0Z3ppxaW0IkJ8C3xRZYeKSKTLq4DpSa5cgmhSmLFtyoELhExbq WaHX7x6yAWqr3lFdOPPp3wdjI9pGeULz4bZjaxWQjKx+D7Qe8ARRaakeH P0AsWpcrQngO87xCgtop5Eg0OHMxj003stOz2dgiE1WlNbRyC++rpBmSi F6we0RTTS/VH0/DIYvymsvrmhpsxXHJqvD48bz2+zbpaL2HD87ALp70bN D587IgKvSPFDMaCj5VOPQobsaXMTQhdxZZ6RtNvqhhMJaaZo/bAWV/Met A==; X-IronPort-AV: E=McAfee;i="6600,9927,10775"; a="452737931" X-IronPort-AV: E=Sophos;i="6.01,215,1684825200"; d="scan'208";a="452737931" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jul 2023 20:06:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10775"; a="727161982" X-IronPort-AV: E=Sophos;i="6.01,215,1684825200"; d="scan'208";a="727161982" Received: from zengguan-mobl1.ccr.corp.intel.com (HELO [10.238.2.33]) ([10.238.2.33]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jul 2023 20:06:16 -0700 Message-ID: <69afdc99-df5d-678e-5a63-2ef33c607d3a@intel.com> Date: Wed, 19 Jul 2023 11:05:40 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v2 0/8] LASS KVM virtualization support Content-Language: en-US To: Paolo Bonzini , "Christopherson,, Sean" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , H Peter Anvin , "kvm@vger.kernel.org" Cc: "x86@kernel.org" , "linux-kernel@vger.kernel.org" References: <20230718131844.5706-1-guang.zeng@intel.com> From: Zeng Guang In-Reply-To: <20230718131844.5706-1-guang.zeng@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Please ignore this patch set as I posted wrong one by mistake. I will submit the correct patch series soon. Sorry for bothering. On 7/18/2023 9:18 PM, Zeng, Guang wrote: > Linear Address Space Separation (LASS)[1] is a new mechanism that > enforces the same mode-based protections as paging, i.e. SMAP/SMEP > but without traversing the paging structures. Because the protections > enforced by LASS are applied before paging, "probes" by malicious > software will provide no paging-based timing information. > > Based on a linear-address organization, LASS partitions 64-bit linear > address space into two halves, user-mode address (LA[bit 63]=0) and > supervisor-mode address (LA[bit 63]=1). > > LASS aims to prevent any attempt to probe supervisor-mode addresses by > user mode, and likewise stop any attempt to access (if SMAP enabled) or > execute user-mode addresses from supervisor mode. > > When platform has LASS capability, KVM requires to expose this feature > to guest VM enumerated by CPUID.(EAX=07H.ECX=1):EAX.LASS[bit 6], and > allow guest to enable it via CR4.LASS[bit 27] on demand. For instruction > executed in the guest directly, hardware will perform the check. But KVM > also needs to behave same as hardware to apply LASS to kinds of guest > memory accesses when emulating instructions by software. > > KVM will take following LASS violations check on emulation path. > User-mode access to supervisor space address: > LA[bit 63] && (CPL == 3) > Supervisor-mode access to user space address: > Instruction fetch: !LA[bit 63] && (CPL < 3) > Data access: !LA[bit 63] && (CR4.SMAP==1) && ((RFLAGS.AC == 0 && > CPL < 3) || Implicit supervisor access) > > This patch series provide a LASS KVM solution and depends on kernel > enabling that can be found at > https://lore.kernel.org/all/20230609183632.48706-1-alexander.shishkin@linux.intel.com/ > > We tested the basic function of LASS virtualization including LASS > enumeration and enabling in non-root and nested environment. As KVM > unittest framework is not compatible to LASS rule, we use kernel module > and application test to emulate LASS violation instead. With KVM forced > emulation mechanism, we also verified the LASS functionality on some > emulation path with instruction fetch and data access to have same > behavior as hardware. > > How to extend kselftest to support LASS is under investigation and > experiment. > > [1] Intel ISE https://cdrdv2.intel.com/v1/dl/getContent/671368 > Chapter Linear Address Space Separation (LASS) > > ------------------------------------------------------------------------ > > v1->v2 > 1. refactor and optimize the interface of instruction emulation > by introducing new set of operation type definition prefixed with > "X86EMUL_F_" to distinguish access. > 2. reorganize the patch to make each area of KVM better isolated. > 3. refine LASS violation check design with consideration of wraparound > access across address space boundary. > > v0->v1 > 1. Adapt to new __linearize() API > 2. Function refactor of vmx_check_lass() > 3. Refine commit message to be more precise > 4. Drop LASS kvm cap detection depending > on hardware capability > > Binbin Wu (4): > KVM: x86: Consolidate flags for __linearize() > KVM: x86: Use a new flag for branch instructions > KVM: x86: Add an emulation flag for implicit system access > KVM: x86: Add X86EMUL_F_INVTLB and pass it in em_invlpg() > > Zeng Guang (4): > KVM: emulator: Add emulation of LASS violation checks on linear > address > KVM: VMX: Implement and apply vmx_is_lass_violation() for LASS > protection > KVM: x86: Virtualize CR4.LASS > KVM: x86: Advertise LASS CPUID to user space > > arch/x86/include/asm/kvm-x86-ops.h | 3 ++- > arch/x86/include/asm/kvm_host.h | 5 +++- > arch/x86/kvm/cpuid.c | 5 ++-- > arch/x86/kvm/emulate.c | 37 ++++++++++++++++++++--------- > arch/x86/kvm/kvm_emulate.h | 9 +++++++ > arch/x86/kvm/vmx/nested.c | 3 ++- > arch/x86/kvm/vmx/sgx.c | 4 ++++ > arch/x86/kvm/vmx/vmx.c | 38 ++++++++++++++++++++++++++++++ > arch/x86/kvm/vmx/vmx.h | 3 +++ > arch/x86/kvm/x86.c | 10 ++++++++ > arch/x86/kvm/x86.h | 2 ++ > 11 files changed, 102 insertions(+), 17 deletions(-) >