diff --git a/sys/geom/geom_disk.c b/sys/geom/geom_disk.c
index 57dab5f72e4..6ac4a59008c 100644
--- a/sys/geom/geom_disk.c
+++ b/sys/geom/geom_disk.c
@@ -53,6 +53,7 @@
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <geom/geom.h>
+#include <geom/geom_int.h>
 
 static struct mtx g_disk_done_mtx;
 
@@ -252,7 +253,8 @@ g_disk_start(struct bio *bp)
 			break;
 		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
 			g_disk_kerneldump(bp, dp);
-		else if ((dp->d_ioctl != NULL) &&
+		else if ((g_debugflags & G_F_DISKIOCTL) &&
+		    (dp->d_ioctl != NULL) &&
 		    !strcmp(bp->bio_attribute, "GEOM::ioctl") &&
 		    bp->bio_length == sizeof *gio) {
 			gio = (struct g_ioctl *)bp->bio_data;
diff --git a/sys/geom/geom_int.h b/sys/geom/geom_int.h
index 81f80692bb0..0b55670482b 100644
--- a/sys/geom/geom_int.h
+++ b/sys/geom/geom_int.h
@@ -46,9 +46,12 @@ extern int g_debugflags;
  * 1	G_T_TOPOLOGY
  * 2	G_T_BIO
  * 4	G_T_ACCESS
- * 8	enable sanity checks
+ * 8	Enable sanity checks
  * 16	Allow footshooting on rank#1 providers
+ * 32	G_T_DETAILS
  */
+#define G_F_DISKIOCTL	64
+
 
 /*
  * Various internal actions are tracked by tagging g_event[s] onto