From patchwork Thu Apr 23 02:25:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11504869 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DD2D31667 for ; Thu, 23 Apr 2020 02:26:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CEEA120CC7 for ; Thu, 23 Apr 2020 02:26:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726602AbgDWC0A (ORCPT ); Wed, 22 Apr 2020 22:26:00 -0400 Received: from mga06.intel.com ([134.134.136.31]:33065 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726581AbgDWCZ7 (ORCPT ); Wed, 22 Apr 2020 22:25:59 -0400 IronPort-SDR: REO5yVs0shxwcwZlDnWQB6Bc3qxgbwrXiDpp5iIFTtearGmtFxPBo3fH5I40+cpdQHb7hVyocw vhT8E0xUwH3Q== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Apr 2020 19:25:55 -0700 IronPort-SDR: 2Z/0fy1Rj0mpp5HFgJpPAkSaA7HUQoMV89zmGJqKByl/vjrCA/CzdXYCq+JEjbLy8gSDNGasTb 0NBw3t7FIu0Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,305,1583222400"; d="scan'208";a="259273964" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga006.jf.intel.com with ESMTP; 22 Apr 2020 19:25:54 -0700 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, Oliver Upton , Peter Shier Subject: [PATCH 11/13] KVM: VMX: Use vmx_interrupt_blocked() directly from vmx_handle_exit() Date: Wed, 22 Apr 2020 19:25:48 -0700 Message-Id: <20200423022550.15113-12-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200423022550.15113-1-sean.j.christopherson@intel.com> References: <20200423022550.15113-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Use vmx_interrupt_blocked() instead of bouncing through vmx_interrupt_allowed() when handling edge cases in vmx_handle_exit(). The nested_run_pending check in vmx_interrupt_allowed() should never evaluate true in the VM-Exit path. Hoist the WARN in handle_invalid_guest_state() up to vmx_handle_exit() to enforce the above assumption for the !enable_vnmi case, and to detect any other potential bugs with nested VM-Enter. Signed-off-by: Sean Christopherson Reviewed-by: Jim Mattson --- arch/x86/kvm/vmx/vmx.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 50c726a21feb..2f8cacb3aa9b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5268,18 +5268,11 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu) bool intr_window_requested; unsigned count = 130; - /* - * We should never reach the point where we are emulating L2 - * due to invalid guest state as that means we incorrectly - * allowed a nested VMEntry with an invalid vmcs12. - */ - WARN_ON_ONCE(vmx->emulation_required && vmx->nested.nested_run_pending); - intr_window_requested = exec_controls_get(vmx) & CPU_BASED_INTR_WINDOW_EXITING; while (vmx->emulation_required && count-- != 0) { - if (intr_window_requested && vmx_interrupt_allowed(vcpu)) + if (intr_window_requested && !vmx_interrupt_blocked(vcpu)) return handle_interrupt_window(&vmx->vcpu); if (kvm_test_request(KVM_REQ_EVENT, vcpu)) @@ -5896,6 +5889,14 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, if (enable_pml) vmx_flush_pml_buffer(vcpu); + /* + * We should never reach this point with a pending nested VM-Enter, and + * more specifically emulation of L2 due to invalid guest state (see + * below) should never happen as that means we incorrectly allowed a + * nested VM-Enter with an invalid vmcs12. + */ + WARN_ON_ONCE(vmx->nested.nested_run_pending); + /* If guest state is invalid, start emulating */ if (vmx->emulation_required) return handle_invalid_guest_state(vcpu); @@ -5962,7 +5963,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, if (unlikely(!enable_vnmi && vmx->loaded_vmcs->soft_vnmi_blocked)) { - if (vmx_interrupt_allowed(vcpu)) { + if (!vmx_interrupt_blocked(vcpu)) { vmx->loaded_vmcs->soft_vnmi_blocked = 0; } else if (vmx->loaded_vmcs->vnmi_blocked_time > 1000000000LL && vcpu->arch.nmi_pending) {