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 EADEFC43334 for ; Tue, 14 Jun 2022 21:59:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358438AbiFNV7E (ORCPT ); Tue, 14 Jun 2022 17:59:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358019AbiFNV6m (ORCPT ); Tue, 14 Jun 2022 17:58:42 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F234A1D322 for ; Tue, 14 Jun 2022 14:58:41 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id b6-20020a252e46000000b0065d5168f3f0so8597770ybn.21 for ; Tue, 14 Jun 2022 14:58:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=hM7xMbhXzzpQsznI3mGO8g+Dd+xj8PMNtipqtZvGG6k=; b=GuwmpLX88ftCnnpvqBc0WWzPL0wSNukaXGYAF8kRU3fV4GL4+B9Elr4s4+wWKQ3/Rz xg+LLlOREPuRcRxHZKOFIBVH6tpVgBcu+qg1SyPbYUuTj2LeHp4CzOFvYXE9NL+dQt1o +Vw0KhKxEtxeoXYu9Sj5Zl0XeKb8VflPBYqi0tGcGGuDmaOIEC/hxaGQZMlFoiLPgt48 m0Gk4uwi/E2c2iCDlKMiCd0GOlJfPgP6eKlWtS1GaMP4EVNyXrivSMOwwTyNIvKB+PBU uf651/XmhZiMVcMv1l9rlJ/4l5c6D+8s/y89roi6/XOnE9ZysvYaodORfCg8EVWtW3J0 zs1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=hM7xMbhXzzpQsznI3mGO8g+Dd+xj8PMNtipqtZvGG6k=; b=k/0phgAMahsIQWJC/tjdHHu+JsSsxQ0SxvfBUemORZnTLyxcjKpQtU1WV+QuojzboU okx+93OYPwkOpWPknU8QP7NAhg2yRVZhzP1rejxwhxjZz8kH3Ac4hxyi+Ur0fVR4AaGB CA24ND8w48fTFEY6f1zMW1a907AfVXAZPWyX3CbNAoSHPhKtlk9auPgTZyllRCZ9l06n iWW0lk528vgRhBydH0hoaLLpeHTQZayltBkq+/4YwEEmZYc38fLroTmHT1J1PQ1XAJVS tMskrA/Gat1iyaUg8JPQTMcglkngNacQbtj7znPS0wGDoMTznppK6TPdE0CN0Xkwy30U iNUQ== X-Gm-Message-State: AJIora86JFEPfPYJTd0jPdg+h7oZuguH7AcTfkXjRACLw6Xaf5OADS9L r1601RPPwh3P9tsiTN37qsktHgnkkZ8= X-Google-Smtp-Source: AGRyM1tLv+/JKHGTDIKQSxOo/noztvW59rm5koNkZaEIoKlUtzDtwmNubj8LmcaWwHqarnkYTx9vUqSqWNs= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a25:c544:0:b0:663:896f:2236 with SMTP id v65-20020a25c544000000b00663896f2236mr6636975ybe.234.1655243921135; Tue, 14 Jun 2022 14:58:41 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 14 Jun 2022 21:58:30 +0000 In-Reply-To: <20220614215831.3762138-1-seanjc@google.com> Message-Id: <20220614215831.3762138-5-seanjc@google.com> Mime-Version: 1.0 References: <20220614215831.3762138-1-seanjc@google.com> X-Mailer: git-send-email 2.36.1.476.g0c4daa206d-goog Subject: [PATCH 4/5] KVM: nVMX: Save BNDCFGS to vmcs12 iff relevant controls are exposed to L1 From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Lei Wang Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Save BNDCFGS to vmcs12 (from vmcs02) if and only if at least of one of the load-on-entry or clear-on-exit fields for BNDCFGS is enumerated as an allowed-1 bit in vmcs12. Skipping the field avoids an unnecessary VMREAD when MPX is supported but not exposed to L1. Per Intel's SDM: If the processor supports either the 1-setting of the "load IA32_BNDCFGS" VM-entry control or that of the "clear IA32_BNDCFGS" VM-exit control, the contents of the IA32_BNDCFGS MSR are saved into the corresponding field. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/nested.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 38015f4ecc54..496981b86f94 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4104,7 +4104,8 @@ static void sync_vmcs02_to_vmcs12_rare(struct kvm_vcpu *vcpu, vmcs12->guest_idtr_base = vmcs_readl(GUEST_IDTR_BASE); vmcs12->guest_pending_dbg_exceptions = vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS); - if (kvm_mpx_supported()) + if ((vmx->nested.msrs.entry_ctls_high & VM_ENTRY_LOAD_BNDCFGS) || + (vmx->nested.msrs.exit_ctls_high & VM_EXIT_CLEAR_BNDCFGS)) vmcs12->guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS); vmx->nested.need_sync_vmcs02_to_vmcs12_rare = false; -- 2.36.1.476.g0c4daa206d-goog