diff --git a/sys/dev/disk/nata/atapi-fd.c b/sys/dev/disk/nata/atapi-fd.c
--- a/sys/dev/disk/nata/atapi-fd.c
+++ b/sys/dev/disk/nata/atapi-fd.c
@@ -458,8 +458,8 @@
 		  ata_mode2str(atadev->mode));
     if (bootverbose) {
 	device_printf(dev, "%ju sectors [%juC/%dH/%dS]\n",
-		      fdp->mediasize / fdp->sectorsize,
-		     fdp->mediasize/(fdp->sectorsize*fdp->sectors*fdp->heads),
+		      (fdp->sectorsize ? fdp->mediasize / fdp->sectorsize : 0),
+		     (fdp->sectorsize && fdp->sectors && fdp->heads) ? fdp->mediasize/(fdp->sectorsize*fdp->sectors*fdp->heads) : 0,
 		      fdp->heads, fdp->sectors);
     }
 }