From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754780AbaDFXjO (ORCPT ); Sun, 6 Apr 2014 19:39:14 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:59431 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754641AbaDFXjG (ORCPT ); Sun, 6 Apr 2014 19:39:06 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Paolo Bonzini" , "Marcelo Tosatti" Date: Mon, 07 Apr 2014 00:35:48 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 15/18] KVM: MMU: handle invalid root_hpa at __direct_map In-Reply-To: X-SA-Exim-Connect-IP: 192.168.2.102 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.57-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marcelo Tosatti commit 989c6b34f6a9480e397b170cc62237e89bf4fdb9 upstream. It is possible for __direct_map to be called on invalid root_hpa (-1), two examples: 1) try_async_pf -> can_do_async_pf -> vmx_interrupt_allowed -> nested_vmx_vmexit 2) vmx_handle_exit -> vmx_interrupt_allowed -> nested_vmx_vmexit Then to load_vmcs12_host_state and kvm_mmu_reset_context. Check for this possibility, let fault exception be regenerated. BZ: https://bugzilla.redhat.com/show_bug.cgi?id=924916 Signed-off-by: Marcelo Tosatti Signed-off-by: Paolo Bonzini Signed-off-by: Ben Hutchings --- arch/x86/kvm/mmu.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2451,6 +2451,9 @@ static int __direct_map(struct kvm_vcpu int emulate = 0; gfn_t pseudo_gfn; + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return 0; + for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { if (iterator.level == level) { unsigned pte_access = ACC_ALL;