From patchwork Fri Jun 16 02:38:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yan Zhao X-Patchwork-Id: 13281974 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 F11AEEB64D9 for ; Fri, 16 Jun 2023 03:04:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241272AbjFPDED (ORCPT ); Thu, 15 Jun 2023 23:04:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229654AbjFPDD7 (ORCPT ); Thu, 15 Jun 2023 23:03:59 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F30AC2D47; Thu, 15 Jun 2023 20:03:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1686884638; x=1718420638; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=tApTo48fmEWmOt000/vMI+RpIzA2pYKklHGoAN2lprc=; b=DCilRLKjlPcbjNYarsrjYWgkn934h+4jjB88EP+z5vlvBftB7ok9v1Mw HydxmHlgzrXTb4w/ksrTd3wuhEQD82n4fYODyBb+Gfzg+dRxDruGSv4Mu AQ2z+cZx38yCvX3J201s/CbEzHU+/iLY/Dy+4msQDelUQHLNy3DkYHzOY HhzjGxgyZr8H6kHLauEC3MMQ3ZZY+zkyJCd1hlkvk0y3Ip9gS0j1F9CKz 9qjCRhwtjgNtwfVkgKfIzH8dGFiORlBjWWSDVy5EBQH63I4JWJh1tdSo8 Fef0qiupUYibaur28516osfkm0nqtAo4xPgYqSSVKJhVf4qFiSm8T9Enl w==; X-IronPort-AV: E=McAfee;i="6600,9927,10742"; a="357976726" X-IronPort-AV: E=Sophos;i="6.00,246,1681196400"; d="scan'208";a="357976726" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2023 20:03:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10742"; a="782724568" X-IronPort-AV: E=Sophos;i="6.00,246,1681196400"; d="scan'208";a="782724568" Received: from yzhao56-desk.sh.intel.com ([10.239.159.62]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2023 20:03:34 -0700 From: Yan Zhao To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: pbonzini@redhat.com, seanjc@google.com, chao.gao@intel.com, kai.huang@intel.com, robert.hoo.linux@gmail.com, Yan Zhao Subject: [PATCH v3 07/11] KVM: VMX: drop IPAT in memtype when CD=1 for KVM_X86_QUIRK_CD_NW_CLEARED Date: Fri, 16 Jun 2023 10:38:15 +0800 Message-Id: <20230616023815.7439-1-yan.y.zhao@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230616023101.7019-1-yan.y.zhao@intel.com> References: <20230616023101.7019-1-yan.y.zhao@intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org For KVM_X86_QUIRK_CD_NW_CLEARED, remove the ignore PAT bit in EPT memory types when cache is disabled and non-coherent DMA are present. With the quirk KVM_X86_QUIRK_CD_NW_CLEARED, WB + IPAT are returned as the EPT memory type when guest cache is disabled before this patch. Removing the IPAT bit in this patch will allow effective memory type to honor PAT values as well, which will make the effective memory type stronger than WB as WB is the weakest memtype. However, this change is acceptable as it doesn't make the memory type weaker, consider without this quirk, the original memtype for cache disabled is UC + IPAT. Suggested-by: Sean Christopherson Signed-off-by: Yan Zhao --- arch/x86/kvm/vmx/vmx.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0ecf4be2c6af..c1e93678cea4 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7548,8 +7548,6 @@ static int vmx_vm_init(struct kvm *kvm) static u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { - u8 cache; - /* We wanted to honor guest CD/MTRR/PAT, but doing so could result in * memory aliases with conflicting memory types and sometimes MCEs. * We have to be careful as to what are honored and when. @@ -7576,11 +7574,10 @@ static u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) if (kvm_read_cr0_bits(vcpu, X86_CR0_CD)) { if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED)) - cache = MTRR_TYPE_WRBACK; + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT; else - cache = MTRR_TYPE_UNCACHABLE; - - return (cache << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT; + return (MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT) | + VMX_EPT_IPAT_BIT; } return kvm_mtrr_get_guest_memory_type(vcpu, gfn) << VMX_EPT_MT_EPTE_SHIFT;