[PATCH 5.10 093/120] KVM: x86: Set so called reserved CR3 bits in LM mask at vCPU reset

Greg Kroah-Hartman
2021-02-08T17:33:25Z

From: Sean Christopherson <seanjc@google.com>

commit 031b91a5fe6f1ce61b7617614ddde9ed61e252be upstream.

Set cr3_lm_rsvd_bits, which is effectively an invalid GPA mask, at vCPU
reset. The reserved bits check needs to be done even if userspace never
configures the guest's CPUID model.

Cc: stable@vger.kernel.org
Fixes: 0107973a80ad ("KVM: x86: Introduce cr3_lm_rsvd_bits in kvm_vcpu_arch")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210204000117.3303214-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/x86.c | 1 +
1 file changed, 1 insertion(+)

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9915,6 +9915,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu
fx_init(vcpu);

vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
+ vcpu->arch.cr3_lm_rsvd_bits = rsvd_bits(cpuid_maxphyaddr(vcpu), 63);

vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT;