KVM: X86: Provide a capability to disable HLT intercepts

If host CPUs are dedicated to a VM, we can avoid VM exits on HLT.
This patch adds the per-VM capability to disable them.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index f6578ce..0f801d8 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1380,7 +1380,6 @@ static void init_vmcb(struct vcpu_svm *svm)
 	set_intercept(svm, INTERCEPT_RDPMC);
 	set_intercept(svm, INTERCEPT_CPUID);
 	set_intercept(svm, INTERCEPT_INVD);
-	set_intercept(svm, INTERCEPT_HLT);
 	set_intercept(svm, INTERCEPT_INVLPG);
 	set_intercept(svm, INTERCEPT_INVLPGA);
 	set_intercept(svm, INTERCEPT_IOIO_PROT);
@@ -1403,6 +1402,9 @@ static void init_vmcb(struct vcpu_svm *svm)
 		set_intercept(svm, INTERCEPT_MWAIT);
 	}
 
+	if (!kvm_hlt_in_guest(svm->vcpu.kvm))
+		set_intercept(svm, INTERCEPT_HLT);
+
 	control->iopm_base_pa = __sme_set(iopm_base);
 	control->msrpm_base_pa = __sme_set(__pa(svm->msrpm));
 	control->int_ctl = V_INTR_MASKING_MASK;