diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 60a5cf40d49a..d56da1db8ba0 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -28,7 +28,7 @@
 #define IOINT_AI_MASK 0x04000000
 #define PFAULT_INIT 0x0600
 
-static int deliver_ckc_interrupt(struct kvm_vcpu *vcpu);
+static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu);
 
 static int is_ioint(u64 type)
 {
@@ -77,7 +77,7 @@ static u64 int_word_to_isc_bits(u32 int_word)
 	return (0x80 >> isc) << 24;
 }
 
-static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
+static int __must_check __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
 				      struct kvm_s390_interrupt_info *inti)
 {
 	switch (inti->type) {
@@ -225,7 +225,7 @@ static u16 get_ilc(struct kvm_vcpu *vcpu)
 	}
 }
 
-static int __deliver_prog_irq(struct kvm_vcpu *vcpu,
+static int __must_check __deliver_prog_irq(struct kvm_vcpu *vcpu,
 			      struct kvm_s390_pgm_info *pgm_info)
 {
 	int rc = 0;
@@ -307,7 +307,7 @@ static int __deliver_prog_irq(struct kvm_vcpu *vcpu,
 	return rc;
 }
 
-static int __do_deliver_interrupt(struct kvm_vcpu *vcpu,
+static int __must_check __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 				   struct kvm_s390_interrupt_info *inti)
 {
 	const unsigned short table[] = { 2, 4, 4, 6 };
@@ -508,7 +508,7 @@ static int __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 	return rc;
 }
 
-static int deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
+static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
 {
 	int rc;
 
@@ -657,7 +657,7 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
 			  &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl);
 }
 
-int kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
+int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 {
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 	struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 99abcb56e478..b1a77669137b 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -138,7 +138,7 @@ static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm)
 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu);
 void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu);
 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer);
-int kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
+int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
 void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu);
 void kvm_s390_clear_float_irqs(struct kvm *kvm);
 int __must_check kvm_s390_inject_vm(struct kvm *kvm,