diff --git a/lib/nvme/nvme_uevent.c b/lib/nvme/nvme_uevent.c
index 1bcfff1cb..a41f8bbe4 100644
--- a/lib/nvme/nvme_uevent.c
+++ b/lib/nvme/nvme_uevent.c
@@ -144,9 +144,7 @@ parse_event(const char *buf, struct spdk_uevent *event)
 			return -1;
 		}
 		spdk_pci_addr_fmt(event->traddr, sizeof(event->traddr), &pci_addr);
-		return 1;
-	}
-	if (!strncmp(driver, "vfio-pci", 8)) {
+	} else if (!strncmp(driver, "vfio-pci", 8)) {
 		struct spdk_pci_addr pci_addr;
 
 		event->subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_VFIO;
@@ -161,10 +159,11 @@ parse_event(const char *buf, struct spdk_uevent *event)
 			return -1;
 		}
 		spdk_pci_addr_fmt(event->traddr, sizeof(event->traddr), &pci_addr);
-		return 1;
-
+	} else {
+		event->subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 	}
-	return -1;
+
+	return 1;
 }
 
 int
diff --git a/lib/nvme/nvme_uevent.h b/lib/nvme/nvme_uevent.h
index 778d73c2a..94f67101e 100644
--- a/lib/nvme/nvme_uevent.h
+++ b/lib/nvme/nvme_uevent.h
@@ -41,6 +41,7 @@
 #ifndef SPDK_UEVENT_H_
 #define SPDK_UEVENT_H_
 
+#define SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED 0
 #define SPDK_NVME_UEVENT_SUBSYSTEM_UIO 1
 #define SPDK_NVME_UEVENT_SUBSYSTEM_VFIO 2
 
diff --git a/test/unit/lib/nvme/nvme_uevent.c/nvme_uevent_ut.c b/test/unit/lib/nvme/nvme_uevent.c/nvme_uevent_ut.c
index a9775c983..c5a94223d 100644
--- a/test/unit/lib/nvme/nvme_uevent.c/nvme_uevent_ut.c
+++ b/test/unit/lib/nvme/nvme_uevent.c/nvme_uevent_ut.c
@@ -47,8 +47,6 @@ enum uevent_parse_event_return_type {
 	uevent_expected_continue = 1
 };
 
-#define SPDK_NVME_UEVENT_SUBSYSTEM_NULL 0xFF
-
 static void
 test_nvme_uevent_parse_event(void)
 {
@@ -62,19 +60,19 @@ test_nvme_uevent_parse_event(void)
 	/* Case 1: Add wrong non-uio or vfio-pci /devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0 */
 	commands =
 		"ACTION=add\0DEVPATH=/devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0\0SUBSYSTEM= \0DRIVER= \0PCI_SLOT_NAME= \0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = 0xFF;
 	uevent.action = 0;
 
 	rc = parse_event(commands, &uevent);
 
-	CU_ASSERT(rc == uevent_abnormal_exit);
-	CU_ASSERT(uevent.subsystem == SPDK_NVME_UEVENT_SUBSYSTEM_NULL);
+	CU_ASSERT(rc == uevent_expected_continue);
+	CU_ASSERT(uevent.subsystem == SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED);
 	CU_ASSERT(uevent.action == SPDK_NVME_UEVENT_ADD);
 
 	/* Case 2: Add uio /devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0 */
 	commands =
 		"ACTION=add \0DEVPATH=/devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0\0SUBSYSTEM=uio\0DRIVER=\0PCI_SLOT_NAME= \0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 	uevent.action = 0;
 
 	rc = parse_event(commands, &uevent);
@@ -86,7 +84,7 @@ test_nvme_uevent_parse_event(void)
 	/* Case 3: Remove uio /devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0 */
 	commands =
 		"ACTION=remove\0DEVPATH=/devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0\0SUBSYSTEM=uio\0DRIVER=\0PCI_SLOT_NAME= \0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 
 	rc = parse_event(commands, &uevent);
 
@@ -96,7 +94,7 @@ test_nvme_uevent_parse_event(void)
 
 	/* Case 4: Add vfio-pci 0000:81:00.0 */
 	commands = "ACTION=bind\0DEVPATH=\0SUBSYSTEM= \0DRIVER=vfio-pci\0PCI_SLOT_NAME=0000:81:00.0\0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 
 	rc = parse_event(commands, &uevent);
 
@@ -106,7 +104,7 @@ test_nvme_uevent_parse_event(void)
 
 	/* Case 5: Remove vfio-pci 0000:81:00.0 */
 	commands = "ACTION=remove\0DEVPATH= \0SUBSYSTEM= \0DRIVER=vfio-pci \0PCI_SLOT_NAME=0000:81:00.0\0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 
 	rc = parse_event(commands, &uevent);
 
@@ -116,7 +114,7 @@ test_nvme_uevent_parse_event(void)
 
 	/* Case 6: Add wrong vfio-pci addr 000000 */
 	commands = "ACTION=bind\0DEVPATH= \0SUBSYSTEM= \0DRIVER=vfio-pci \0PCI_SLOT_NAME=000000\0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED;
 
 	rc = parse_event(commands, &uevent);
 
@@ -126,12 +124,12 @@ test_nvme_uevent_parse_event(void)
 
 	/* Case 7: Add wrong type vfio 0000:81:00.0 */
 	commands = "ACTION=bind\0DEVPATH= \0SUBSYSTEM= \0DRIVER=vfio \0PCI_SLOT_NAME=0000:81:00.0\0";
-	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_NULL;
+	uevent.subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UIO;
 	uevent.action = 0;
 	rc = parse_event(commands, &uevent);
 
-	CU_ASSERT(rc == uevent_abnormal_exit);
-	CU_ASSERT(uevent.subsystem == SPDK_NVME_UEVENT_SUBSYSTEM_NULL);
+	CU_ASSERT(rc == uevent_expected_continue);
+	CU_ASSERT(uevent.subsystem == SPDK_NVME_UEVENT_SUBSYSTEM_UNRECOGNIZED);
 	CU_ASSERT(uevent.action == SPDK_NVME_UEVENT_ADD);
 }