Respond to @amotin's latest comments:

* Remove an unhelpful assertion
* Move dn_maxblkid access out of the db_rwlock region

Author: asomers

module/zfs/dbuf.c

@@ -4663,21 +4663,21 @@ dbuf_lightweight_ready(zio_t *zio)
 	    bp_get_dsize_sync(spa, bp_orig);
 	dnode_diduse_space(dn, delta);
 
-	uint64_t blkid = dr->dt.dll.dr_blkid;
-	mutex_enter(&dn->dn_mtx);
-	if (blkid > dn->dn_phys->dn_maxblkid) {
-		ASSERT0(dn->dn_objset->os_raw_receive);
-		dn->dn_phys->dn_maxblkid = blkid;
-	}
-	mutex_exit(&dn->dn_mtx);
-
 	if (!BP_IS_EMBEDDED(bp)) {
 		uint64_t fill = BP_IS_HOLE(bp) ? 0 : 1;
 		BP_SET_FILL(bp, fill);
 	}
 
 	*bp_orig = *bp;
 	rw_exit(&parent_db->db_rwlock);
+
+	uint64_t blkid = dr->dt.dll.dr_blkid;
+	mutex_enter(&dn->dn_mtx);
+	if (blkid > dn->dn_phys->dn_maxblkid) {
+		ASSERT0(dn->dn_objset->os_raw_receive);
+		dn->dn_phys->dn_maxblkid = blkid;
+	}
+	mutex_exit(&dn->dn_mtx);
 }
 
 static void

module/zfs/dnode_sync.c

@@ -564,7 +564,6 @@ dnode_undirty_dbufs(list_t *list)
 		ASSERT(list_head(&db->db_dirty_records) == dr);
 		list_remove_head(&db->db_dirty_records);
 		ASSERT(list_is_empty(&db->db_dirty_records));
-		ASSERT(MUTEX_HELD(&db->db_mtx));
 		db->db_dirtycnt -= 1;
 		if (db->db_level == 0) {
 			ASSERT(db->db_blkid == DMU_BONUS_BLKID ||