From nobody Sun Sep 7 12:24:19 2025 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 4E913CDB465 for ; Mon, 16 Oct 2023 16:18:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233998AbjJPQSr (ORCPT ); Mon, 16 Oct 2023 12:18:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234092AbjJPQSX (ORCPT ); Mon, 16 Oct 2023 12:18:23 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 891CAD49; Mon, 16 Oct 2023 09:17:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697473054; x=1729009054; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LZtjKP0zUaYueJKf49xZZ2JcB5JrAggPB5C1l4MJZbo=; b=QsBjH62h74sjaPVo1CoZiJuLa2G5CWDu0JwFgaBLoJ2WKi1j9LkPXVSa Z6I0CzZKc33pbqtFtx2+6GQ7kqZgHoAtOvyxEoKZ7fuvLGk1AW1RvxeG9 X3KryRX4HWfXKOsupsY9PMeCj+iI/ctXnbAUl/9KvmkVisc5+Eiess+ff XSvufJDd2HMCNw3O5Lw/IxVqKM9ve65HZX3vxUKrohBCqlQlkv9ICyVMC v0QeW50YsbkeM4YBBbaL8yMASW6jLaZpqaMNZppjv940/Fgd5PjQpvXir BrApoGKqMLbujbrF8QRcn9Q53mAcXn6aDun12LPRT22b+xDX7Ijo0RmBP w==; X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="364921870" X-IronPort-AV: E=Sophos;i="6.03,229,1694761200"; d="scan'208";a="364921870" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 09:15:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="846448189" X-IronPort-AV: E=Sophos;i="6.03,229,1694761200"; d="scan'208";a="846448189" Received: from ls.sc.intel.com (HELO localhost) ([172.25.112.31]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 09:15:51 -0700 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack , Kai Huang , Zhi Wang , chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com Subject: [PATCH v16 064/116] KVM: TDX: restore host xsave state when exit from the guest TD Date: Mon, 16 Oct 2023 09:14:16 -0700 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Isaku Yamahata On exiting from the guest TD, xsave state is clobbered. Restore xsave state on TD exit. Signed-off-by: Isaku Yamahata --- v15 -> v16: - Added CET flag mask --- arch/x86/kvm/vmx/tdx.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index add9a0083adb..98827160c6f9 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -2,6 +2,7 @@ #include #include =20 +#include #include =20 #include "capabilities.h" @@ -508,6 +509,23 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_e= vent) */ } =20 +static void tdx_restore_host_xsave_state(struct kvm_vcpu *vcpu) +{ + struct kvm_tdx *kvm_tdx =3D to_kvm_tdx(vcpu->kvm); + + if (static_cpu_has(X86_FEATURE_XSAVE) && + host_xcr0 !=3D (kvm_tdx->xfam & kvm_caps.supported_xcr0)) + xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0); + if (static_cpu_has(X86_FEATURE_XSAVES) && + /* PT can be exposed to TD guest regardless of KVM's XSS support */ + host_xss !=3D (kvm_tdx->xfam & + (kvm_caps.supported_xss | XFEATURE_MASK_PT | TDX_TD_XFAM_CET))) + wrmsrl(MSR_IA32_XSS, host_xss); + if (static_cpu_has(X86_FEATURE_PKU) && + (kvm_tdx->xfam & XFEATURE_MASK_PKRU)) + write_pkru(vcpu->arch.host_pkru); +} + static noinstr void tdx_vcpu_enter_exit(struct vcpu_tdx *tdx) { struct tdx_module_args args; @@ -583,6 +601,7 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) =20 tdx_vcpu_enter_exit(tdx); =20 + tdx_restore_host_xsave_state(vcpu); tdx->host_state_need_restore =3D true; =20 vcpu->arch.regs_avail &=3D ~VMX_REGS_LAZY_LOAD_SET; --=20 2.25.1