Index: usr.sbin/bhyve/pci_nvme.c
===================================================================
--- usr.sbin/bhyve/pci_nvme.c
+++ usr.sbin/bhyve/pci_nvme.c
@@ -30,7 +30,7 @@
  * bhyve PCIe-NVMe device emulation.
  *
  * options:
- *  -s <n>,nvme,devpath,maxq=#,qsz=#,ioslots=#,sectsz=#,ser=A-Z
+ *  -s <n>,nvme,devpath,maxq=#,qsz=#,ioslots=#,sectsz=#,ser=A-Z,eui64=#
  *
  *  accepted devpath:
  *    /dev/blockdev
@@ -42,6 +42,7 @@
  *  ioslots = max number of concurrent io requests
  *  sectsz  = sector size (defaults to blockif sector size)
  *  ser     = serial number (20-chars max)
+ *  eui64   = IEEE Extended Unique Identifier (8 byte value)
  *
  */
 
@@ -164,6 +165,7 @@
 	uint64_t	size;
 	uint32_t	sectsz;
 	uint32_t	sectsz_bits;
+	uint64_t	eui64;
 };
 
 struct pci_nvme_ioreq {
@@ -353,11 +355,11 @@
 }
 
 static void
-pci_nvme_init_nsdata(struct pci_nvme_softc *sc)
+pci_nvme_init_nsdata(struct pci_nvme_softc *sc,
+    struct nvme_namespace_data *nd, uint32_t nsid,
+    uint64_t eui64)
 {
-	struct nvme_namespace_data *nd;
-
-	nd = &sc->nsdata;
+	uint16_t be_nsid;
 
 	nd->nsze = sc->nvstore.size / sc->nvstore.sectsz;
 	nd->ncap = nd->nsze;
@@ -365,10 +367,28 @@
 
 	/* Get LBA and backstore information from backing store */
 	nd->nlbaf = 0; /* NLBAF is a 0's based value (i.e. 1 LBA Format) */
+
+	nd->flbas = 0;
+
+	/* Create an EUI-64 if user did not provide one */
+	if (eui64 != 0)
+		memcpy(nd->eui64, &eui64, sizeof(nd->eui64));
+	else {
+		/* OUI followed by the PCI BDF and the Namespace ID */
+		memcpy(nd->eui64, sc->ctrldata.ieee, 3);
+
+		nd->eui64[3] = sc->nsc_pi->pi_bus;
+		nd->eui64[4] = sc->nsc_pi->pi_slot;
+		nd->eui64[5] = sc->nsc_pi->pi_func;
+
+		assert(nsid <= UINT16_MAX);
+
+		be_nsid = htobe16(nsid);
+		memcpy(nd->eui64 + 6, &be_nsid, 2);
+	}
+
 	/* LBA data-sz = 2^lbads */
 	nd->lbaf[0] = sc->nvstore.sectsz_bits << NVME_NS_DATA_LBAF_LBADS_SHIFT;
-
-	nd->flbas = 0;
 }
 
 static void
@@ -1816,6 +1836,8 @@
 				free(uopt);
 				return (-1);
 			}
+		} else if (!strcmp("eui64", xopts)) {
+			sc->nvstore.eui64 = htobe64(strtoull(config, NULL, 0));
 		} else if (optidx == 0) {
 			snprintf(bident, sizeof(bident), "%d:%d",
 			         sc->nsc_pi->pi_slot, sc->nsc_pi->pi_func);
@@ -1936,7 +1958,7 @@
 
 	pci_nvme_reset(sc);
 	pci_nvme_init_ctrldata(sc);
-	pci_nvme_init_nsdata(sc);
+	pci_nvme_init_nsdata(sc, &sc->nsdata, 0, sc->nvstore.eui64);
 	pci_nvme_init_logpages(sc);
 
 	pci_lintr_request(pi);