diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c
index 5dc4636..1c15ea6 100644
--- a/sys/kern/vfs_cache.c
+++ b/sys/kern/vfs_cache.c
@@ -1134,6 +1134,7 @@ retry:
 						/* forced unmount */
 						vrele(*vpp);
 						*vpp = NULL;
+						printf("%s: failing dot lookup for %p\n", __func__, *vpp);
 						return (ENOENT);
 					}
 				} else
@@ -1641,6 +1642,16 @@ cache_enter_time(struct vnode *dvp, struct vnode *vp, struct componentname *cnp,
 		if (n2->nc_dvp == dvp &&
 		    n2->nc_nlen == cnp->cn_namelen &&
 		    !bcmp(nc_get_name(n2), cnp->cn_nameptr, n2->nc_nlen)) {
+			if ((n2->nc_flag & NCF_NEGATIVE) || vp == NULL) {
+				if ((n2->nc_flag & NCF_NEGATIVE && vp != NULL) ||
+				   (!(n2->nc_flag & NCF_NEGATIVE) && vp == NULL)) {
+					printf("%s: dvp %p name [%s] positive vs negative entry (found %p, inserting %p)\n", __func__,
+						dvp, cnp->cn_nameptr, n2->nc_vp, ncp->nc_vp);
+				}
+			} else if (n2->nc_vp != ncp->nc_vp) {
+				printf("%s: dvp %p name [%s] positive entry conflict (found %p, inserting %p)\n", __func__,
+					dvp, cnp->cn_nameptr, n2->nc_vp, ncp->nc_vp);
+			}
 			if (tsp != NULL) {
 				KASSERT((n2->nc_flag & NCF_TS) != 0,
 				    ("no NCF_TS"));