kvm: fix wrong exception emulation in check_rdtsc

According to Intel's SDM Vol2 and AMD's APM Vol3, when
CR4.TSD is set, use rdtsc/rdtscp instruction above privilege
level 0 should trigger a #GP.

Fixes: d7eb82030699e ("KVM: SVM: Add intercept checks for remaining group7 instructions")
Signed-off-by: Hou Wenlong <houwenlong93@linux.alibaba.com>
Message-Id: <1297c0dd3f1bb47a6d089f850b629c7aa0247040.1629257115.git.houwenlong93@linux.alibaba.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2837110..c589ac8 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4206,7 +4206,7 @@ static int check_rdtsc(struct x86_emulate_ctxt *ctxt)
        u64 cr4 = ctxt->ops->get_cr(ctxt, 4);
 
        if (cr4 & X86_CR4_TSD && ctxt->ops->cpl(ctxt))
-               return emulate_ud(ctxt);
+               return emulate_gp(ctxt, 0);
 
        return X86EMUL_CONTINUE;
 }