diff --git a/sys/ufs/ffs/ffs_softdep.c b/sys/ufs/ffs/ffs_softdep.c
index 785f430786cb..e55464eb9004 100644
--- a/sys/ufs/ffs/ffs_softdep.c
+++ b/sys/ufs/ffs/ffs_softdep.c
@@ -56,6 +56,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/systm.h>
 #include <sys/bio.h>
 #include <sys/buf.h>
+#include <sys/kdb.h>
 #include <sys/malloc.h>
 #include <sys/mount.h>
 #include <sys/proc.h>
@@ -5866,7 +5867,7 @@ getdirtybuf(bpp, mtx, waitfor)
 		if ((bp = *bpp) == NULL)
 			return (0);
 		if (bp->b_vp == NULL)
-			backtrace();
+			kdb_backtrace();
 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL) == 0) {
 			if ((bp->b_vflags & BV_BKGRDINPROG) == 0)
 				break;
diff --git a/sys/ufs/ffs/ffs_subr.c b/sys/ufs/ffs/ffs_subr.c
index 08f60cee5290..84295b9bba55 100644
--- a/sys/ufs/ffs/ffs_subr.c
+++ b/sys/ufs/ffs/ffs_subr.c
@@ -39,8 +39,6 @@ __FBSDID("$FreeBSD$");
 #include <ufs/ffs/fs.h>
 #include "fsck.h"
 #else
-#include "opt_ddb.h"
-
 #include <sys/systm.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
@@ -58,7 +56,7 @@ __FBSDID("$FreeBSD$");
 #include <ufs/ffs/ffs_extern.h>
 #include <ufs/ffs/fs.h>
 
-#ifdef DDB
+#ifdef KDB
 void	ffs_checkoverlap(struct buf *, struct inode *);
 #endif
 
@@ -168,7 +166,7 @@ ffs_fragacct(fs, fragmap, fraglist, cnt)
 	}
 }
 
-#ifdef DDB
+#ifdef KDB
 void
 ffs_checkoverlap(bp, ip)
 	struct buf *bp;
@@ -197,7 +195,7 @@ ffs_checkoverlap(bp, ip)
 		panic("ffs_checkoverlap: Disk buffer overlap");
 	}
 }
-#endif /* DDB */
+#endif /* KDB */
 
 /*
  * block operations