diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
index 53ce78d7d07be0f68834046f2c4d10cb6c63fed9..5e2e1b9a9fd3af111dfee7385f315cbfed1f792d 100644
--- a/drivers/vfio/pci/Kconfig
+++ b/drivers/vfio/pci/Kconfig
@@ -2,6 +2,7 @@
 config VFIO_PCI
 	tristate "VFIO support for PCI devices"
 	depends on VFIO && PCI && EVENTFD
+	depends on MMU
 	select VFIO_VIRQFD
 	select IRQ_BYPASS_MANAGER
 	help
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index d57f037f65b85d48942e17a659e9bb7bc0fd137d..70e28efbc51f80e04b87edd010d8d27799795cca 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1581,7 +1581,7 @@ static int vfio_ecap_init(struct vfio_pci_device *vdev)
 			if (len == 0xFF) {
 				len = vfio_ext_cap_len(vdev, ecap, epos);
 				if (len < 0)
-					return ret;
+					return len;
 			}
 		}
 
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 361e5b57e369327e4143717025d7aaad75765d7a..470fcf7dac564cece9a6fdc867b9e646649d6df6 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -291,7 +291,7 @@ static int vfio_platform_open(struct vfio_device *core_vdev)
 	vfio_platform_regions_cleanup(vdev);
 err_reg:
 	mutex_unlock(&driver_lock);
-	module_put(THIS_MODULE);
+	module_put(vdev->parent_module);
 	return ret;
 }
 
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index a0747c35a7781ec3b71b1d06583abbcb05a9e6e2..a3e925a41b0de881d2a2e358ce4cb5fb7c93be33 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -2795,7 +2795,7 @@ static int vfio_iommu_iova_build_caps(struct vfio_iommu *iommu,
 		return 0;
 	}
 
-	size = sizeof(*cap_iovas) + (iovas * sizeof(*cap_iovas->iova_ranges));
+	size = struct_size(cap_iovas, iova_ranges, iovas);
 
 	cap_iovas = kzalloc(size, GFP_KERNEL);
 	if (!cap_iovas)
diff --git a/samples/vfio-mdev/mdpy-fb.c b/samples/vfio-mdev/mdpy-fb.c
index 21dbf63d6e415f19a0c795d51d62bd17e7a1f344..9ec93d90e8a5a647f1e8ddce1ed2f005abdfeeee 100644
--- a/samples/vfio-mdev/mdpy-fb.c
+++ b/samples/vfio-mdev/mdpy-fb.c
@@ -117,22 +117,27 @@ static int mdpy_fb_probe(struct pci_dev *pdev,
 	if (format != DRM_FORMAT_XRGB8888) {
 		pci_err(pdev, "format mismatch (0x%x != 0x%x)\n",
 			format, DRM_FORMAT_XRGB8888);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_release_regions;
 	}
 	if (width < 100	 || width > 10000) {
 		pci_err(pdev, "width (%d) out of range\n", width);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_release_regions;
 	}
 	if (height < 100 || height > 10000) {
 		pci_err(pdev, "height (%d) out of range\n", height);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_release_regions;
 	}
 	pci_info(pdev, "mdpy found: %dx%d framebuffer\n",
 		 width, height);
 
 	info = framebuffer_alloc(sizeof(struct mdpy_fb_par), &pdev->dev);
-	if (!info)
+	if (!info) {
+		ret = -ENOMEM;
 		goto err_release_regions;
+	}
 	pci_set_drvdata(pdev, info);
 	par = info->par;