diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index 5533df91b257..67d0bf4efa16 100644
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -21,8 +21,8 @@ config VFIO_VIRQFD
 
 menuconfig VFIO
 	tristate "VFIO Non-Privileged userspace driver framework"
-	depends on IOMMU_API
-	select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM || ARM64)
+	select IOMMU_API
+	select VFIO_IOMMU_TYPE1 if MMU && (X86 || S390 || ARM || ARM64)
 	help
 	  VFIO provides a framework for secure userspace device drivers.
 	  See Documentation/driver-api/vfio.rst for more details.
diff --git a/drivers/vfio/platform/Kconfig b/drivers/vfio/platform/Kconfig
index dc1a3c44f2c6..ab341108a0be 100644
--- a/drivers/vfio/platform/Kconfig
+++ b/drivers/vfio/platform/Kconfig
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 config VFIO_PLATFORM
 	tristate "VFIO support for platform devices"
-	depends on VFIO && EVENTFD && (ARM || ARM64)
+	depends on VFIO && EVENTFD && (ARM || ARM64 || COMPILE_TEST)
 	select VFIO_VIRQFD
 	help
 	  Support for platform devices with VFIO. This is required to make
@@ -12,7 +12,7 @@ config VFIO_PLATFORM
 
 config VFIO_AMBA
 	tristate "VFIO support for AMBA devices"
-	depends on VFIO_PLATFORM && ARM_AMBA
+	depends on VFIO_PLATFORM && (ARM_AMBA || COMPILE_TEST)
 	help
 	  Support for ARM AMBA devices with VFIO. This is required to make
 	  use of ARM AMBA devices present on the system using the VFIO
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 4bb162c1d649..be444407664a 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -189,7 +189,7 @@ static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu,
 }
 
 static struct rb_node *vfio_find_dma_first_node(struct vfio_iommu *iommu,
-						dma_addr_t start, size_t size)
+						dma_addr_t start, u64 size)
 {
 	struct rb_node *res = NULL;
 	struct rb_node *node = iommu->dma_list.rb_node;
@@ -785,7 +785,12 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
 		return -ENODEV;
 
 	ret = vaddr_get_pfns(mm, vaddr, 1, dma->prot, pfn_base, pages);
-	if (ret == 1 && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) {
+	if (ret != 1)
+		goto out;
+
+	ret = 0;
+
+	if (do_accounting && !is_invalid_reserved_pfn(*pfn_base)) {
 		ret = vfio_lock_acct(dma, 1, true);
 		if (ret) {
 			put_pfn(*pfn_base, dma->prot);
@@ -797,6 +802,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
 		}
 	}
 
+out:
 	mmput(mm);
 	return ret;
 }
@@ -1288,7 +1294,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
 	int ret = -EINVAL, retries = 0;
 	unsigned long pgshift;
 	dma_addr_t iova = unmap->iova;
-	unsigned long size = unmap->size;
+	u64 size = unmap->size;
 	bool unmap_all = unmap->flags & VFIO_DMA_UNMAP_FLAG_ALL;
 	bool invalidate_vaddr = unmap->flags & VFIO_DMA_UNMAP_FLAG_VADDR;
 	struct rb_node *n, *first_n;
@@ -1304,14 +1310,12 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
 	if (unmap_all) {
 		if (iova || size)
 			goto unlock;
-		size = SIZE_MAX;
-	} else if (!size || size & (pgsize - 1)) {
+		size = U64_MAX;
+	} else if (!size || size & (pgsize - 1) ||
+		   iova + size - 1 < iova || size > SIZE_MAX) {
 		goto unlock;
 	}
 
-	if (iova + size - 1 < iova || size > SIZE_MAX)
-		goto unlock;
-
 	/* When dirty tracking is enabled, allow only min supported pgsize */
 	if ((unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) &&
 	    (!iommu->dirty_page_tracking || (bitmap->pgsize != pgsize))) {
diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index 6cc93ab5b809..c68d87b87283 100644
--- a/include/linux/amba/bus.h
+++ b/include/linux/amba/bus.h
@@ -105,8 +105,19 @@ extern struct bus_type amba_bustype;
 #define amba_get_drvdata(d)	dev_get_drvdata(&d->dev)
 #define amba_set_drvdata(d,p)	dev_set_drvdata(&d->dev, p)
 
+#ifdef CONFIG_ARM_AMBA
 int amba_driver_register(struct amba_driver *);
 void amba_driver_unregister(struct amba_driver *);
+#else
+static inline int amba_driver_register(struct amba_driver *drv)
+{
+	return -EINVAL;
+}
+static inline void amba_driver_unregister(struct amba_driver *drv)
+{
+}
+#endif
+
 struct amba_device *amba_device_alloc(const char *, resource_size_t, size_t);
 void amba_device_put(struct amba_device *);
 int amba_device_add(struct amba_device *, struct resource *);