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 00854C433EF for ; Thu, 10 Mar 2022 11:19:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236562AbiCJLUH (ORCPT ); Thu, 10 Mar 2022 06:20:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241561AbiCJLUB (ORCPT ); Thu, 10 Mar 2022 06:20:01 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B50388CDB0; Thu, 10 Mar 2022 03:19:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646911140; x=1678447140; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=UYIKoaA6kmpekLkyIKkHDzFL2cnsVds98qcFgEdzL5w=; b=SDesxgD/z7diAP5NwITf/tdGklOEW7jjIiignj25e48poBzKv4ngf1MR fP1R95if4jvP2cfO+N7gzGL/eekDWsRHtpjXmcb3UDBJdf0wX00CMCzsj V5a2eIbkeCkwLLrfMYMACh3cuVy3TukjlQTElcHb4ZxnKi4dQP6lSImSu AUcWjBjKl8dr6OY57sYLOdIXz/zk80DQ6FkIUT6Mz+bZAhT31LtGfLvav i+p+66Lffl5gMEq+uc+8v3RufJggyl6pwBrWaARhfw7EtSxJIo4dxxYzW SMH1Jv/z5UzvldNKqlraBvsP4EI16tP6KLdL0QnXhoO4oHgZfdCeXxp2i A==; X-IronPort-AV: E=McAfee;i="6200,9189,10281"; a="254962715" X-IronPort-AV: E=Sophos;i="5.90,170,1643702400"; d="scan'208";a="254962715" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2022 03:19:00 -0800 X-IronPort-AV: E=Sophos;i="5.90,170,1643702400"; d="scan'208";a="712325502" Received: from duan-server-s2600bt.bj.intel.com ([10.240.192.123]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2022 03:18:58 -0800 From: Zhenzhong Duan To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org Subject: [PATCH] KVM: x86: Remove redundant vm_entry_controls_clearbit() call Date: Thu, 10 Mar 2022 19:13:54 +0800 Message-Id: <20220310111354.504565-1-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When emulating exit from long mode, EFER_LMA is cleared which lead to efer writing emulation, which will unset VM_ENTRY_IA32E_MODE control bit as requested by SDM. So no need to unset VM_ENTRY_IA32E_MODE again in exit_lmode() explicitly. In fact benefited from shadow controls mechanism, this change doesn't eliminate vmread or vmwrite. Opportunistically remove unnecessory assignment to uret MSR data field as vmx_setup_uret_msrs() will do the same thing. In case EFER isn't supported by hardware, long mode isn't supported, so this will no break. Signed-off-by: Zhenzhong Duan --- arch/x86/kvm/vmx/vmx.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b730d799c26e..b04588dc7faa 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2878,14 +2878,11 @@ int vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer) return 0; vcpu->arch.efer = efer; - if (efer & EFER_LMA) { + if (efer & EFER_LMA) vm_entry_controls_setbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE); - msr->data = efer; - } else { + else vm_entry_controls_clearbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE); - msr->data = efer & ~EFER_LME; - } vmx_setup_uret_msrs(vmx); return 0; } @@ -2911,7 +2908,6 @@ static void enter_lmode(struct kvm_vcpu *vcpu) static void exit_lmode(struct kvm_vcpu *vcpu) { - vm_entry_controls_clearbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE); vmx_set_efer(vcpu, vcpu->arch.efer & ~EFER_LMA); } -- 2.25.1