From: Maxim Levitsky mlevitsk@redhat.com
commit 33fbe6befa622c082f7d417896832856814bdde0 upstream.
This shows up as a TDP MMU leak when running nested. Non-working cmpxchg on L0 relies makes L1 install two different shadow pages under same spte, and one of them is leaked.
Fixes: 1c2361f667f36 ("KVM: x86: Use __try_cmpxchg_user() to emulate atomic accesses") Signed-off-by: Maxim Levitsky mlevitsk@redhat.com Message-Id: 20220512101420.306759-1-mlevitsk@redhat.com Reviewed-by: Sean Christopherson seanjc@google.com Reviewed-by: Vitaly Kuznetsov vkuznets@redhat.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kvm/x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7207,7 +7207,7 @@ static int emulator_cmpxchg_emulated(str goto emul_write;
hva = kvm_vcpu_gfn_to_hva(vcpu, gpa_to_gfn(gpa)); - if (kvm_is_error_hva(addr)) + if (kvm_is_error_hva(hva)) goto emul_write;
hva += offset_in_page(gpa);