diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 6113ca785c78..28e3aaa5e482 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -694,7 +694,8 @@ int arch_domain_create(struct domain *d,
                        struct xen_domctl_createdomain *config,
                        unsigned int flags)
 {
-    int rc, count = 0;
+    unsigned int count = 0;
+    int rc;
 
     BUILD_BUG_ON(GUEST_MAX_VCPUS < MAX_VIRT_CPUS);
 
diff --git a/xen/arch/arm/include/asm/mmio.h b/xen/arch/arm/include/asm/mmio.h
index 79e64d9af804..b22cfdac5be9 100644
--- a/xen/arch/arm/include/asm/mmio.h
+++ b/xen/arch/arm/include/asm/mmio.h
@@ -75,8 +75,8 @@ struct mmio_handler {
 };
 
 struct vmmio {
-    int num_entries;
-    int max_num_entries;
+    unsigned int num_entries;
+    unsigned int max_num_entries;
     rwlock_t lock;
     struct mmio_handler *handlers;
 };
@@ -86,7 +86,7 @@ enum io_state try_handle_mmio(struct cpu_user_regs *regs,
 void register_mmio_handler(struct domain *d,
                            const struct mmio_handler_ops *ops,
                            paddr_t addr, paddr_t size, void *priv);
-int domain_io_init(struct domain *d, int max_count);
+int domain_io_init(struct domain *d, unsigned int max_count);
 void domain_io_free(struct domain *d);
 
 void try_decode_instruction(const struct cpu_user_regs *regs,
diff --git a/xen/arch/arm/include/asm/vgic.h b/xen/arch/arm/include/asm/vgic.h
index aa9f49409edc..6901a05c0669 100644
--- a/xen/arch/arm/include/asm/vgic.h
+++ b/xen/arch/arm/include/asm/vgic.h
@@ -304,8 +304,8 @@ extern void vgic_enable_irqs(struct vcpu *v, uint32_t r, int n);
 extern void vgic_set_irqs_pending(struct vcpu *v, uint32_t r,
                                   unsigned int rank);
 extern void register_vgic_ops(struct domain *d, const struct vgic_ops *ops);
-int vgic_v2_init(struct domain *d, int *mmio_count);
-int vgic_v3_init(struct domain *d, int *mmio_count);
+int vgic_v2_init(struct domain *d, unsigned int *mmio_count);
+int vgic_v3_init(struct domain *d, unsigned int *mmio_count);
 
 extern bool vgic_to_sgi(struct vcpu *v, register_t sgir,
                         enum gic_sgi_mode irqmode, int virq,
@@ -352,7 +352,7 @@ int vgic_connect_hw_irq(struct domain *d, struct vcpu *v, unsigned int virq,
 
 bool vgic_evtchn_irq_pending(struct vcpu *v);
 
-int domain_vgic_register(struct domain *d, int *mmio_count);
+int domain_vgic_register(struct domain *d, unsigned int *mmio_count);
 int domain_vgic_init(struct domain *d, unsigned int nr_spis);
 void domain_vgic_free(struct domain *d);
 int vcpu_vgic_init(struct vcpu *v);
diff --git a/xen/arch/arm/io.c b/xen/arch/arm/io.c
index 172583df047f..96c740d5636c 100644
--- a/xen/arch/arm/io.c
+++ b/xen/arch/arm/io.c
@@ -224,7 +224,7 @@ void register_mmio_handler(struct domain *d,
     write_unlock(&vmmio->lock);
 }
 
-int domain_io_init(struct domain *d, int max_count)
+int domain_io_init(struct domain *d, unsigned int max_count)
 {
     rwlock_init(&d->arch.vmmio.lock);
     d->arch.vmmio.num_entries = 0;
diff --git a/xen/arch/arm/vgic-v2.c b/xen/arch/arm/vgic-v2.c
index 35363fee098c..2a2eda2e6f4c 100644
--- a/xen/arch/arm/vgic-v2.c
+++ b/xen/arch/arm/vgic-v2.c
@@ -731,7 +731,7 @@ static const struct vgic_ops vgic_v2_ops = {
     .lpi_get_priority = vgic_v2_lpi_get_priority,
 };
 
-int vgic_v2_init(struct domain *d, int *mmio_count)
+int vgic_v2_init(struct domain *d, unsigned int *mmio_count)
 {
     if ( !vgic_v2_hw.enabled )
     {
diff --git a/xen/arch/arm/vgic-v3.c b/xen/arch/arm/vgic-v3.c
index 1b7173da1e30..05a009409ab8 100644
--- a/xen/arch/arm/vgic-v3.c
+++ b/xen/arch/arm/vgic-v3.c
@@ -1812,7 +1812,7 @@ static const struct vgic_ops v3_ops = {
     .lpi_get_priority = vgic_v3_lpi_get_priority,
 };
 
-int vgic_v3_init(struct domain *d, int *mmio_count)
+int vgic_v3_init(struct domain *d, unsigned int *mmio_count)
 {
     if ( !vgic_v3_hw.enabled )
     {
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 97d6f6106638..afcac791fe4b 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -85,7 +85,7 @@ static void vgic_rank_init(struct vgic_irq_rank *rank, uint8_t index,
         write_atomic(&rank->vcpu[i], vcpu);
 }
 
-int domain_vgic_register(struct domain *d, int *mmio_count)
+int domain_vgic_register(struct domain *d, unsigned int *mmio_count)
 {
     switch ( d->arch.vgic.version )
     {
diff --git a/xen/arch/arm/vgic/vgic-init.c b/xen/arch/arm/vgic/vgic-init.c
index 76b85ea8231b..f8d7d3a226d0 100644
--- a/xen/arch/arm/vgic/vgic-init.c
+++ b/xen/arch/arm/vgic/vgic-init.c
@@ -101,7 +101,7 @@ static void vgic_vcpu_early_init(struct vcpu *vcpu)
  *
  * was: kvm_vgic_create
  */
-int domain_vgic_register(struct domain *d, int *mmio_count)
+int domain_vgic_register(struct domain *d, unsigned int *mmio_count)
 {
     switch ( d->arch.vgic.version )
     {
