KVM: x86: rdpmc emulation checks the counter incorrectly

The rdpmc emulation checks that the counter (ECX) is not higher than 2, without
taking into considerations bits 30:31 role (e.g., bit 30 marks whether the
counter is fixed). The fix uses the pmu information for checking the validity
of the pmu counter.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index a04fe4e..ffa2671 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -194,6 +194,7 @@
 	int (*set_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong value);
 	int (*set_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data);
 	int (*get_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata);
+	int (*check_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc);
 	int (*read_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc, u64 *pdata);
 	void (*halt)(struct x86_emulate_ctxt *ctxt);
 	void (*wbinvd)(struct x86_emulate_ctxt *ctxt);