diff --git a/module/zfs/spa.c b/module/zfs/spa.c
index 7e18048af5e6..961b92d56ac3 100644
--- a/module/zfs/spa.c
+++ b/module/zfs/spa.c
@@ -1597,25 +1597,34 @@ spa_unload(spa_t *spa)
 	spa_wake_waiters(spa);
 
 	/*
-	 * If the log space map feature is enabled and the pool is getting
-	 * exported (but not destroyed), we want to spend some time flushing
-	 * as many metaslabs as we can in an attempt to destroy log space
-	 * maps and save import time.
+	 * If we have set the spa_final_txg, we have already performed the
+	 * tasks below in spa_export_common(). We should not redo it here since
+	 * we may dirty the final TXGs, eg vdev_trim_stop_all() ->
+	 * spa_history_log_internal().
 	 */
-	if (spa_should_flush_logs_on_unload(spa))
-		spa_unload_log_sm_flush_all(spa);
+	if (spa->spa_final_txg == UINT64_MAX) {
+		/*
+		 * If the log space map feature is enabled and the pool is
+		 * getting exported (but not destroyed), we want to spend some
+		 * time flushing as many metaslabs as we can in an attempt to
+		 * destroy log space maps and save import time.
+		 */
+		if (spa_should_flush_logs_on_unload(spa))
+			spa_unload_log_sm_flush_all(spa);
 
-	/*
-	 * Stop async tasks.
-	 */
-	spa_async_suspend(spa);
+		/*
+		 * Stop async tasks.
+		 */
+		spa_async_suspend(spa);
 
-	if (spa->spa_root_vdev) {
-		vdev_t *root_vdev = spa->spa_root_vdev;
-		vdev_initialize_stop_all(root_vdev, VDEV_INITIALIZE_ACTIVE);
-		vdev_trim_stop_all(root_vdev, VDEV_TRIM_ACTIVE);
-		vdev_autotrim_stop_all(spa);
-		vdev_rebuild_stop_all(spa);
+		if (spa->spa_root_vdev) {
+			vdev_t *root_vdev = spa->spa_root_vdev;
+			vdev_initialize_stop_all(root_vdev,
+			    VDEV_INITIALIZE_ACTIVE);
+			vdev_trim_stop_all(root_vdev, VDEV_TRIM_ACTIVE);
+			vdev_autotrim_stop_all(spa);
+			vdev_rebuild_stop_all(spa);
+		}
 	}
 
 	/*
@@ -6427,9 +6436,27 @@ spa_export_common(const char *pool, int new_state, nvlist_t **oldconfig,
 		if (new_state != POOL_STATE_UNINITIALIZED && !hardforce) {
 			spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
 			spa->spa_state = new_state;
+			vdev_config_dirty(spa->spa_root_vdev);
+			spa_config_exit(spa, SCL_ALL, FTAG);
+		}
+
+		/*
+		 * If the log space map feature is enabled and the pool is
+		 * getting exported (but not destroyed), we want to spend some
+		 * time flushing as many metaslabs as we can in an attempt to
+		 * destroy log space maps and save import time. This has to be
+		 * done before we set the spa_final_txg, otherwise
+		 * spa_sync() -> spa_flush_metaslabs() may dirty the final TXGs.
+		 * spa_should_flush_logs_on_unload() should be called after
+		 * spa_state has been set to the new_state.
+		 */
+		if (spa_should_flush_logs_on_unload(spa))
+			spa_unload_log_sm_flush_all(spa);
+
+		if (new_state != POOL_STATE_UNINITIALIZED && !hardforce) {
+			spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
 			spa->spa_final_txg = spa_last_synced_txg(spa) +
 			    TXG_DEFER_SIZE + 1;
-			vdev_config_dirty(spa->spa_root_vdev);
 			spa_config_exit(spa, SCL_ALL, FTAG);
 		}
 	}