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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0514AC433FE for ; Mon, 4 Oct 2021 13:32:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E5E6C61166 for ; Mon, 4 Oct 2021 13:32:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237262AbhJDNeC (ORCPT ); Mon, 4 Oct 2021 09:34:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:47290 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236866AbhJDNbo (ORCPT ); Mon, 4 Oct 2021 09:31:44 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 118516321D; Mon, 4 Oct 2021 13:14:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1633353254; bh=mbmNN62ELByuihih3ryR8Om+bUVPmgYhHcEm5uwHV1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aOLIp+J9p7YIX2MuB6ny9EvbAgETSIydX2r6OwS/nM8me5JO8iUDjRJNhfPJLl/qk OfmVcr5l9q8Vi4Ubid9YWvxN8F6PmudP6n0RuUaPtCLzdbv+6cYp9TCjcCc0J+oUbl nwi2vYWRSLgFcCtfhves9DCNCEopsLM3GzTJ5AKk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Kuznetsov , Paolo Bonzini Subject: [PATCH 5.14 054/172] KVM: nVMX: Filter out all unsupported controls when eVMCS was activated Date: Mon, 4 Oct 2021 14:51:44 +0200 Message-Id: <20211004125046.745188738@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211004125044.945314266@linuxfoundation.org> References: <20211004125044.945314266@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vitaly Kuznetsov commit 8d68bad6d869fae8f4d50ab6423538dec7da72d1 upstream. Windows Server 2022 with Hyper-V role enabled failed to boot on KVM when enlightened VMCS is advertised. Debugging revealed there are two exposed secondary controls it is not happy with: SECONDARY_EXEC_ENABLE_VMFUNC and SECONDARY_EXEC_SHADOW_VMCS. These controls are known to be unsupported, as there are no corresponding fields in eVMCSv1 (see the comment above EVMCS1_UNSUPPORTED_2NDEXEC definition). Previously, commit 31de3d2500e4 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()") introduced the required filtering mechanism for VMX MSRs but for some reason put only known to be problematic (and not full EVMCS1_UNSUPPORTED_* lists) controls there. Note, Windows Server 2022 seems to have gained some sanity check for VMX MSRs: it doesn't even try to launch a guest when there's something it doesn't like, nested_evmcs_check_controls() mechanism can't catch the problem. Let's be bold this time and instead of playing whack-a-mole just filter out all unsupported controls from VMX MSRs. Fixes: 31de3d2500e4 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()") Signed-off-by: Vitaly Kuznetsov Message-Id: <20210907163530.110066-1-vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx/evmcs.c | 12 +++++++++--- arch/x86/kvm/vmx/vmx.c | 9 +++++---- 2 files changed, 14 insertions(+), 7 deletions(-) --- a/arch/x86/kvm/vmx/evmcs.c +++ b/arch/x86/kvm/vmx/evmcs.c @@ -354,14 +354,20 @@ void nested_evmcs_filter_control_msr(u32 switch (msr_index) { case MSR_IA32_VMX_EXIT_CTLS: case MSR_IA32_VMX_TRUE_EXIT_CTLS: - ctl_high &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; + ctl_high &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL; break; case MSR_IA32_VMX_ENTRY_CTLS: case MSR_IA32_VMX_TRUE_ENTRY_CTLS: - ctl_high &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; + ctl_high &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL; break; case MSR_IA32_VMX_PROCBASED_CTLS2: - ctl_high &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES; + ctl_high &= ~EVMCS1_UNSUPPORTED_2NDEXEC; + break; + case MSR_IA32_VMX_PINBASED_CTLS: + ctl_high &= ~EVMCS1_UNSUPPORTED_PINCTRL; + break; + case MSR_IA32_VMX_VMFUNC: + ctl_low &= ~EVMCS1_UNSUPPORTED_VMFUNC; break; } --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1840,10 +1840,11 @@ static int vmx_get_msr(struct kvm_vcpu * &msr_info->data)) return 1; /* - * Enlightened VMCS v1 doesn't have certain fields, but buggy - * Hyper-V versions are still trying to use corresponding - * features when they are exposed. Filter out the essential - * minimum. + * Enlightened VMCS v1 doesn't have certain VMCS fields but + * instead of just ignoring the features, different Hyper-V + * versions are either trying to use them and fail or do some + * sanity checking and refuse to boot. Filter all unsupported + * features out. */ if (!msr_info->host_initiated && vmx->nested.enlightened_vmcs_enabled)