diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 6fda746ba32874999db3fcf68450bcd73a248b48..c90698972f42dd844d309594c701c4851a64a45e 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -415,6 +415,7 @@
 #define   HFSCR_DSCR	__MASK(FSCR_DSCR_LG)
 #define   HFSCR_VECVSX	__MASK(FSCR_VECVSX_LG)
 #define   HFSCR_FP	__MASK(FSCR_FP_LG)
+#define   HFSCR_INTR_CAUSE (ASM_CONST(0xFF) << 56)	/* interrupt cause */
 #define SPRN_TAR	0x32f	/* Target Address Register */
 #define SPRN_LPCR	0x13E	/* LPAR Control Register */
 #define   LPCR_VPM0		ASM_CONST(0x8000000000000000)
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index a876dc3c8e1ffb0a49dd46029f7a29a28bebb27d..e2305962fecfb1a180c91a98f1248c30d5ab73c8 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -86,6 +86,22 @@ static void save_hv_return_state(struct kvm_vcpu *vcpu, int trap,
 	}
 }
 
+static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
+{
+	/*
+	 * Don't let L1 enable features for L2 which we've disabled for L1,
+	 * but preserve the interrupt cause field.
+	 */
+	hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr);
+
+	/* Don't let data address watchpoint match in hypervisor state */
+	hr->dawrx0 &= ~DAWRX_HYP;
+
+	/* Don't let completed instruction address breakpt match in HV state */
+	if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER)
+		hr->ciabr &= ~CIABR_PRIV;
+}
+
 static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
 {
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
@@ -198,6 +214,7 @@ long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 	mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD |
 		LPCR_LPES | LPCR_MER;
 	lpcr = (vc->lpcr & ~mask) | (l2_hv.lpcr & mask);
+	sanitise_hv_regs(vcpu, &l2_hv);
 	restore_hv_regs(vcpu, &l2_hv);
 
 	vcpu->arch.ret = RESUME_GUEST;