Index: sys/contrib/openzfs/module/os/freebsd/zfs/zfs_znode.c
===================================================================
--- sys/contrib/openzfs/module/os/freebsd/zfs/zfs_znode.c
+++ sys/contrib/openzfs/module/os/freebsd/zfs/zfs_znode.c
@@ -540,6 +540,7 @@
 	 * Acquire vnode lock before making it available to the world.
 	 */
 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	VN_LOCK_AREC(vp);
 	if (vp->v_type != VFIFO)
 		VN_LOCK_ASHARE(vp);
Index: sys/fs/autofs/autofs_vnops.c
===================================================================
--- sys/fs/autofs/autofs_vnops.c
+++ sys/fs/autofs/autofs_vnops.c
@@ -704,6 +704,7 @@
 
 	sx_xunlock(&anp->an_vnode_lock);
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }
Index: sys/fs/cd9660/cd9660_vfsops.c
===================================================================
--- sys/fs/cd9660/cd9660_vfsops.c
+++ sys/fs/cd9660/cd9660_vfsops.c
@@ -822,6 +822,7 @@
 	 * XXX need generation number?
 	 */
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }
Index: sys/fs/devfs/devfs_vnops.c
===================================================================
--- sys/fs/devfs/devfs_vnops.c
+++ sys/fs/devfs/devfs_vnops.c
@@ -613,6 +613,7 @@
 		return (error);
 	}
 	if (devfs_allocv_drop_refs(0, dmp, de)) {
+		vgone(vp);
 		vput(vp);
 		return (ENOENT);
 	}
@@ -620,6 +621,7 @@
 	mac_devfs_vnode_associate(mp, de, vp);
 #endif
 	sx_xunlock(&dmp->dm_lock);
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }
Index: sys/fs/ext2fs/ext2_alloc.c
===================================================================
--- sys/fs/ext2fs/ext2_alloc.c
+++ sys/fs/ext2fs/ext2_alloc.c
@@ -480,6 +480,7 @@
 	ip->i_birthtime = ts.tv_sec;
 	ip->i_birthnsec = ts.tv_nsec;
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 
 	return (0);
Index: sys/fs/ext2fs/ext2_vfsops.c
===================================================================
--- sys/fs/ext2fs/ext2_vfsops.c
+++ sys/fs/ext2fs/ext2_vfsops.c
@@ -1308,6 +1308,7 @@
 	 * Finish inode initialization.
 	 */
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }
Index: sys/fs/fdescfs/fdesc_vnops.c
===================================================================
--- sys/fs/fdescfs/fdesc_vnops.c
+++ sys/fs/fdescfs/fdesc_vnops.c
@@ -235,6 +235,7 @@
 	/* If we came here, we can insert it safely. */
 	LIST_INSERT_HEAD(fc, fd, fd_hash);
 	mtx_unlock(&fdesc_hashmtx);
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }
Index: sys/fs/fuse/fuse_node.c
===================================================================
--- sys/fs/fuse/fuse_node.c
+++ sys/fs/fuse/fuse_node.c
@@ -263,6 +263,7 @@
 	if (data->dataflags & FSESS_ASYNC_READ && vtyp != VFIFO)
 		VN_LOCK_ASHARE(*vpp);
 
+	vn_set_state(*vpp, VSTATE_CONSTRUCTED);
 	err = vfs_hash_insert(*vpp, fuse_vnode_hash(nodeid), LK_EXCLUSIVE,
 	    td, &vp2, fuse_vnode_cmp, &nodeid);
 	if (err) {
Index: sys/fs/mntfs/mntfs_vnops.c
===================================================================
--- sys/fs/mntfs/mntfs_vnops.c
+++ sys/fs/mntfs/mntfs_vnops.c
@@ -83,6 +83,9 @@
 	dev_ref(dev);
 	vp->v_rdev = dev;
 
+	VOP_UNLOCK(ovp);
+	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	return (vp);
 }
 
Index: sys/fs/msdosfs/msdosfs_denode.c
===================================================================
--- sys/fs/msdosfs/msdosfs_denode.c
+++ sys/fs/msdosfs/msdosfs_denode.c
@@ -299,6 +299,7 @@
 		}
 	} else
 		nvp->v_type = VREG;
+	vn_set_state(nvp, VSTATE_CONSTRUCTED);
 	ldep->de_modrev = init_va_filerev();
 	*depp = ldep;
 	return (0);
Index: sys/fs/msdosfs/msdosfs_vfsops.c
===================================================================
--- sys/fs/msdosfs/msdosfs_vfsops.c
+++ sys/fs/msdosfs/msdosfs_vfsops.c
@@ -431,8 +431,6 @@
 	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
 
 	devvp = mntfs_allocvp(mp, odevvp);
-	VOP_UNLOCK(odevvp);
-	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 	dev = devvp->v_rdev;
 	if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0,
 	    (uintptr_t)mp) == 0) {
Index: sys/fs/nfsclient/nfs_clnode.c
===================================================================
--- sys/fs/nfsclient/nfs_clnode.c
+++ sys/fs/nfsclient/nfs_clnode.c
@@ -178,6 +178,7 @@
 		uma_zfree(newnfsnode_zone, np);
 		return (error);
 	}
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	error = vfs_hash_insert(vp, hash, lkflags, 
 	    td, &nvp, newnfs_vncmpf, np->n_fhp);
 	if (error)
Index: sys/fs/nfsclient/nfs_clport.c
===================================================================
--- sys/fs/nfsclient/nfs_clport.c
+++ sys/fs/nfsclient/nfs_clport.c
@@ -286,6 +286,7 @@
 		uma_zfree(newnfsnode_zone, np);
 		return (error);
 	}
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	error = vfs_hash_insert(vp, hash, lkflags, 
 	    td, &nvp, newnfs_vncmpf, nfhp);
 	if (error)
Index: sys/fs/nullfs/null_subr.c
===================================================================
--- sys/fs/nullfs/null_subr.c
+++ sys/fs/nullfs/null_subr.c
@@ -262,6 +262,7 @@
 	}
 
 	null_hashins(mp, xp);
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	rw_wunlock(&null_hash_lock);
 	*vpp = vp;
 
Index: sys/fs/pseudofs/pseudofs_vncache.c
===================================================================
--- sys/fs/pseudofs/pseudofs_vncache.c
+++ sys/fs/pseudofs/pseudofs_vncache.c
@@ -207,6 +207,7 @@
 		*vpp = NULLVP;
 		return (error);
 	}
+	vn_set_state(*vpp, VSTATE_CONSTRUCTED);
 retry2:
 	mtx_lock(&pfs_vncache_mutex);
 	/*
Index: sys/fs/smbfs/smbfs_node.c
===================================================================
--- sys/fs/smbfs/smbfs_node.c
+++ sys/fs/smbfs/smbfs_node.c
@@ -217,6 +217,7 @@
 		free(np, M_SMBNODE);
 		return (error);
 	}
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	error = vfs_hash_insert(vp, smbfs_hash(name, nmlen), LK_EXCLUSIVE,
 	    td, &vp2, smbfs_vnode_cmp, &sc);
 	if (error) 
Index: sys/fs/tmpfs/tmpfs_subr.c
===================================================================
--- sys/fs/tmpfs/tmpfs_subr.c
+++ sys/fs/tmpfs/tmpfs_subr.c
@@ -1080,6 +1080,8 @@
 		vgone(vp);
 		vput(vp);
 		vp = NULL;
+	} else {
+		vn_set_state(vp, VSTATE_CONSTRUCTED);
 	}
 
 unlock:
Index: sys/fs/udf/udf_vfsops.c
===================================================================
--- sys/fs/udf/udf_vfsops.c
+++ sys/fs/udf/udf_vfsops.c
@@ -717,6 +717,7 @@
 	if (ino == udf_getid(&udfmp->root_icb))
 		vp->v_vflag |= VV_ROOT;
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 
 	return (0);
Index: sys/fs/unionfs/union_subr.c
===================================================================
--- sys/fs/unionfs/union_subr.c
+++ sys/fs/unionfs/union_subr.c
@@ -407,6 +407,8 @@
 		return (ENOENT);
 	}
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
+
 	if (dvp != NULLVP && vt == VDIR)
 		*vpp = unionfs_ins_cached_vnode(unp, dvp);
 	if (*vpp != NULLVP) {
Index: sys/kern/vfs_lookup.c
===================================================================
--- sys/kern/vfs_lookup.c
+++ sys/kern/vfs_lookup.c
@@ -161,6 +161,7 @@
 	    UMA_ALIGN_PTR, 0);
 	vfs_vector_op_register(&crossmp_vnodeops);
 	getnewvnode("crossmp", NULL, &crossmp_vnodeops, &vp_crossmp);
+	vp_crossmp->v_state = VSTATE_CONSTRUCTED;
 }
 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nameiinit, NULL);
 
Index: sys/kern/vfs_subr.c
===================================================================
--- sys/kern/vfs_subr.c
+++ sys/kern/vfs_subr.c
@@ -603,6 +603,8 @@
 
 	vp->v_dbatchcpu = NOCPU;
 
+	vp->v_state = VSTATE_DEAD;
+
 	/*
 	 * Check vhold_recycle_free for an explanation.
 	 */
@@ -1792,6 +1794,9 @@
 		vp = vn_alloc(mp);
 	}
 	counter_u64_add(vnodes_created, 1);
+
+	vn_set_state(vp, VSTATE_UNINITIALIZED);
+
 	/*
 	 * Locks are given the generic name "vnode" when created.
 	 * Follow the historic practice of using the filesystem
@@ -4015,14 +4020,18 @@
 	/*
 	 * Don't vgonel if we're already doomed.
 	 */
-	if (VN_IS_DOOMED(vp))
+	if (VN_IS_DOOMED(vp)) {
+		VNPASS(vn_get_state(vp) == VSTATE_DESTROYING || \
+		    vn_get_state(vp) == VSTATE_DEAD, vp);
 		return;
+	}
 	/*
 	 * Paired with freevnode.
 	 */
 	vn_seqc_write_begin_locked(vp);
 	vunlazy_gone(vp);
 	vn_irflag_set_locked(vp, VIRF_DOOMED);
+	vn_set_state(vp, VSTATE_DESTROYING);
 
 	/*
 	 * Check to see if the vnode is in use.  If so, we have to
@@ -4140,14 +4149,28 @@
 	vp->v_vnlock = &vp->v_lock;
 	vp->v_op = &dead_vnodeops;
 	vp->v_type = VBAD;
+	vn_set_state(vp, VSTATE_DEAD);
 }
 
 /*
  * Print out a description of a vnode.
  */
-static const char * const typename[] =
-{"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
- "VMARKER"};
+static const char *const vtypename[] = {
+ [VNON] = "VNON", [VREG] = "VREG", [VDIR] = "VDIR", [VBLK] = "VBLK",
+ [VCHR] = "VCHR", [VLNK] = "VLNK", [VSOCK] = "VSOCK", [VFIFO] = "VFIFO",
+ [VBAD] = "VBAD", [VMARKER] = "VMARKER"
+};
+_Static_assert(nitems(vtypename) == VLASTTYPE + 1,
+    "vnode type name not added to vtypename");
+
+static const char *const vstatename[] = {
+ [VSTATE_UNINITIALIZED] = "VSTATE_UNINITIALIZED",
+ [VSTATE_CONSTRUCTED] = "VSTATE_CONSTRUCTED",
+ [VSTATE_DESTROYING] = "VSTATE_DESTROYING",
+ [VSTATE_DEAD] = "VSTATE_DEAD",
+};
+_Static_assert(nitems(vstatename) == VLASTSTATE + 1,
+    "vnode state name not added to vstatename");
 
 _Static_assert((VHOLD_ALL_FLAGS & ~VHOLD_NO_SMR) == 0,
     "new hold count flag not added to vn_printf");
@@ -4165,7 +4188,7 @@
 	vprintf(fmt, ap);
 	va_end(ap);
 	printf("%p: ", (void *)vp);
-	printf("type %s\n", typename[vp->v_type]);
+	printf("type %s state %s\n", vtypename[vp->v_type], vstatename[vp->v_state]);
 	holdcnt = atomic_load_int(&vp->v_holdcnt);
 	printf("    usecount %d, writecount %d, refcount %d seqc users %d",
 	    vp->v_usecount, vp->v_writecount, holdcnt & ~VHOLD_ALL_FLAGS,
@@ -5063,6 +5086,7 @@
 	if (error != 0)
 		panic("vfs_allocate_syncvnode: insmntque() failed");
 	vp->v_vflag &= ~VV_FORCEINSMQ;
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	VOP_UNLOCK(vp);
 	/*
 	 * Place the vnode onto the syncer worklist. We attempt to
@@ -5709,8 +5733,11 @@
 vop_unlock_debugpre(void *ap)
 {
 	struct vop_unlock_args *a = ap;
+	struct vnode *vp = a->a_vp;
+
+	VNPASS(vn_get_state(vp) != VSTATE_UNINITIALIZED, vp);
 
-	ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
+	ASSERT_VOP_LOCKED(vp, "VOP_UNLOCK");
 }
 
 void
@@ -7082,3 +7109,51 @@
 	vn_irflag_unset_locked(vp, tounset);
 	VI_UNLOCK(vp);
 }
+
+#ifdef INVARIANTS
+void
+vn_set_state_validate(struct vnode *vp, enum vstate state)
+{
+
+	switch (vp->v_state) {
+	case VSTATE_UNINITIALIZED:
+		switch (state) {
+		case VSTATE_CONSTRUCTED:
+		case VSTATE_DESTROYING:
+			return;
+		default:
+			break;
+		}
+		break;
+	case VSTATE_CONSTRUCTED:
+		ASSERT_VOP_ELOCKED(vp, __func__);
+		switch (state) {
+		case VSTATE_DESTROYING:
+			return;
+		default:
+			break;
+		}
+		break;
+	case VSTATE_DESTROYING:
+		ASSERT_VOP_ELOCKED(vp, __func__);
+		switch (state) {
+		case VSTATE_DEAD:
+			return;
+		default:
+			break;
+		}
+		break;
+	case VSTATE_DEAD:
+		switch (state) {
+		case VSTATE_UNINITIALIZED:
+			return;
+		default:
+			break;
+		}
+		break;
+	}
+
+	vn_printf(vp, "invalid state transition %d -> %d\n", vp->v_state, state);
+	panic("invalid state transition %d -> %d\n", vp->v_state, state);
+}
+#endif
Index: sys/sys/vnode.h
===================================================================
--- sys/sys/vnode.h
+++ sys/sys/vnode.h
@@ -58,6 +58,11 @@
  */
 enum vtype	{ VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD,
 		  VMARKER };
+#define VLASTTYPE VMARKER
+
+enum vstate	{ VSTATE_UNINITIALIZED, VSTATE_CONSTRUCTED, VSTATE_DESTROYING,
+		  VSTATE_DEAD };
+#define VLASTSTATE VSTATE_DEAD
 
 enum vgetstate	{ VGET_NONE, VGET_HOLDCNT, VGET_USECOUNT };
 /*
@@ -106,6 +111,7 @@
 	 * owned by the filesystem (XXX: and vgone() ?)
 	 */
 	enum	vtype v_type:8;			/* u vnode type */
+	enum	vstate v_state:8;		/* u vnode state */
 	short	v_irflag;			/* i frequently read flags */
 	seqc_t	v_seqc;				/* i modification count */
 	uint32_t v_nchash;			/* u namecache hash */
@@ -1135,6 +1141,25 @@
 int vn_dir_check_exec(struct vnode *vp, struct componentname *cnp);
 int vn_lktype_write(struct mount *mp, struct vnode *vp);
 
+#ifdef INVARIANTS
+void vn_set_state_validate(struct vnode *vp, enum vstate state);
+#endif
+
+static inline void
+vn_set_state(struct vnode *vp, enum vstate state)
+{
+#ifdef INVARIANTS
+	vn_set_state_validate(vp, state);
+#endif
+	vp->v_state = state;
+}
+
+static inline enum vstate
+vn_get_state(struct vnode *vp)
+{
+	return (vp->v_state);
+}
+
 #define VOP_UNLOCK_FLAGS(vp, flags)	({				\
 	struct vnode *_vp = (vp);					\
 	int _flags = (flags);						\
Index: sys/ufs/ffs/ffs_vfsops.c
===================================================================
--- sys/ufs/ffs/ffs_vfsops.c
+++ sys/ufs/ffs/ffs_vfsops.c
@@ -925,8 +925,6 @@
 	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
 
 	devvp = mntfs_allocvp(mp, odevvp);
-	VOP_UNLOCK(odevvp);
-	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 	KASSERT(devvp->v_type == VCHR, ("reclaimed devvp"));
 	dev = devvp->v_rdev;
 	KASSERT(dev->si_snapdata == NULL, ("non-NULL snapshot data"));
@@ -2028,6 +2026,7 @@
 	}
 #endif
 
+	vn_set_state(vp, VSTATE_CONSTRUCTED);
 	*vpp = vp;
 	return (0);
 }