diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 3b931056edf5..4d410aa6ec2e 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -171,6 +171,16 @@ vinvalbuf(struct vnode *vp, int flags, kauth_cred_t cred, struct lwp *l,
 	mutex_enter(&bufcache_lock);
 restart:
 	for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
+		if (bp->b_vp != vp) {
+			if (bp->b_vp)
+				vprint("bp->b_vp", bp->b_vp);
+			else
+				printf("bp->b_vp is null\n");
+			if (vp)
+				vprint("vp", vp);
+			else
+				printf("vp is null\n");
+		}
 		KASSERT(bp->b_vp == vp);
 		nbp = LIST_NEXT(bp, b_vnbufs);
 		error = bbusy(bp, catch_p, slptimeo, NULL);
@@ -184,6 +194,16 @@ restart:
 	}
 
 	for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
+		if (bp->b_vp != vp) {
+			if (bp->b_vp)
+				vprint("bp->b_vp", bp->b_vp);
+			else
+				printf("bp->b_vp is null\n");
+			if (vp)
+				vprint("vp", vp);
+			else
+				printf("vp is null\n");
+		}
 		KASSERT(bp->b_vp == vp);
 		nbp = LIST_NEXT(bp, b_vnbufs);
 		error = bbusy(bp, catch_p, slptimeo, NULL);
@@ -1119,6 +1139,14 @@ vprint_common(struct vnode *vp, const char *prefix,
 	    ARRAY_PRINT(vp->v_tag, vnode_tags), vp->v_tag,
 	    ARRAY_PRINT(vp->v_type, vnode_types), vp->v_type,
 	    vp->v_mount, vp->v_mountedhere);
+	switch (vp->v_type) {
+	case VBLK:
+	case VCHR:
+		(*pr)("%s  rdev=0x%lx\n", prefix, vp->v_rdev);
+		break;
+	default:
+		break;
+	}
 	(*pr)("%susecount %d writecount %d holdcount %d\n", prefix,
 	    vrefcnt(vp), vp->v_writecount, vp->v_holdcnt);
 	(*pr)("%ssize %" PRIx64 " writesize %" PRIx64 " numoutput %d\n",