Index: usr.sbin/bhyve/pci_nvme.c
===================================================================
--- usr.sbin/bhyve/pci_nvme.c
+++ usr.sbin/bhyve/pci_nvme.c
@@ -62,6 +62,7 @@
 #include <sys/errno.h>
 #include <sys/types.h>
 #include <net/ieee_oui.h>
+#include <sys/time.h>
 
 #include <assert.h>
 #include <pthread.h>
@@ -241,6 +242,8 @@
     struct nvme_command *,
     struct nvme_completion *);
 
+typedef struct timeval timeval_t;
+
 struct nvme_feature_obj {
 	uint32_t	cdw11;
 	nvme_feature_cb	set;
@@ -300,6 +303,7 @@
 	__uint128_t	write_commands;
 	uint32_t	read_dunits_remainder;
 	uint32_t	write_dunits_remainder;
+	timeval_t	power_on_time;
 
 	STAILQ_HEAD(, pci_nvme_aer) aer_list;
 	uint32_t	aer_count;
@@ -503,6 +507,8 @@
 	cd->fna = 0x03;
 
 	cd->power_state[0].mp = 10;
+
+	gettimeofday(&sc->power_on_time, NULL);
 }
 
 /*
@@ -596,6 +602,7 @@
 static void
 pci_nvme_init_logpages(struct pci_nvme_softc *sc)
 {
+	__uint128_t	power_cycles = 1;
 
 	memset(&sc->err_log, 0, sizeof(sc->err_log));
 	memset(&sc->health_log, 0, sizeof(sc->health_log));
@@ -609,6 +616,8 @@
 	sc->health_log.temperature = 310;
 	sc->health_log.available_spare = 100;
 	sc->health_log.available_spare_threshold = 10;
+	memcpy(&sc->health_log.power_cycles, &power_cycles,
+	    sizeof(sc->health_log.power_cycles));
 }
 
 static void
@@ -1071,6 +1080,8 @@
 {
 	uint32_t logsize;
 	uint8_t logpage = command->cdw10 & 0xFF;
+	timeval_t now;
+	__uint128_t power_on_hours;
 
 	DPRINTF("%s log page %u len %u", __func__, logpage, logsize);
 
@@ -1091,6 +1102,9 @@
 		    NVME_COPY_TO_PRP);
 		break;
 	case NVME_LOG_HEALTH_INFORMATION:
+		gettimeofday(&now, NULL);
+		power_on_hours = (now.tv_sec - sc->power_on_time.tv_sec) / 3600;
+
 		pthread_mutex_lock(&sc->mtx);
 		memcpy(&sc->health_log.data_units_read, &sc->read_data_units,
 		    sizeof(sc->health_log.data_units_read));
@@ -1100,6 +1114,8 @@
 		    sizeof(sc->health_log.host_read_commands));
 		memcpy(&sc->health_log.host_write_commands, &sc->write_commands,
 		    sizeof(sc->health_log.host_write_commands));
+		memcpy(&sc->health_log.power_on_hours, &power_on_hours,
+		    sizeof(sc->health_log.power_on_hours));
 		pthread_mutex_unlock(&sc->mtx);
 
 		nvme_prp_memcpy(sc->nsc_pi->pi_vmctx, command->prp1,