Index: head/sys/dev/nvme/nvme.c
===================================================================
--- head/sys/dev/nvme/nvme.c
+++ head/sys/dev/nvme/nvme.c
@@ -54,9 +54,7 @@
 
 uma_zone_t	nvme_request_zone;
 int32_t		nvme_retry_count;
-int		nvme_verbose_cmd_dump;
 
-TUNABLE_INT("hw.nvme.verbose_cmd_dump", &nvme_verbose_cmd_dump);
 
 MALLOC_DEFINE(M_NVME, "nvme", "nvme(4) memory allocations");
 
Index: head/sys/dev/nvme/nvme_private.h
===================================================================
--- head/sys/dev/nvme/nvme_private.h
+++ head/sys/dev/nvme/nvme_private.h
@@ -114,7 +114,7 @@
 
 extern uma_zone_t	nvme_request_zone;
 extern int32_t		nvme_retry_count;
-extern int32_t		nvme_verbose_cmd_dump;
+extern bool		nvme_verbose_cmd_dump;
 
 struct nvme_completion_poll_status {
 
Index: head/sys/dev/nvme/nvme_sysctl.c
===================================================================
--- head/sys/dev/nvme/nvme_sysctl.c
+++ head/sys/dev/nvme/nvme_sysctl.c
@@ -42,10 +42,14 @@
 #endif
 
 int nvme_use_nvd = NVME_USE_NVD;
+bool nvme_verbose_cmd_dump = false;
 
 SYSCTL_NODE(_hw, OID_AUTO, nvme, CTLFLAG_RD, 0, "NVMe sysctl tunables");
 SYSCTL_INT(_hw_nvme, OID_AUTO, use_nvd, CTLFLAG_RDTUN,
     &nvme_use_nvd, 1, "1 = Create NVD devices, 0 = Create NDA devices");
+SYSCTL_BOOL(_hw_nvme, OID_AUTO, verbose_cmd_dump, CTLFLAG_RWTUN,
+    &nvme_verbose_cmd_dump, 0,
+    "enable verbose command printting when a command fails");
 
 /*
  * CTLTYPE_S64 and sysctl_handle_64 were added in r217616.  Define these