From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marcelo Tosatti , Paolo Bonzini , Josh Boyer Subject: [PATCH 3.4 10/13] KVM: MMU: handle invalid root_hpa at __direct_map Date: Fri, 28 Mar 2014 10:32:00 -0700 Message-Id: <20140328173054.448665049@linuxfoundation.org> In-Reply-To: <20140328173053.049244535@linuxfoundation.org> References: <20140328173053.049244535@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable 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 Cc: Josh Boyer Signed-off-by: Greg Kroah-Hartman --- 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;