Borrow a fix from FreeBSD: add boolean spa_splitting_newspa for `zpoo…

…l split`

include/sys/spa_impl.h

@@ -247,6 +247,9 @@ struct spa {
 	 */
 	spa_config_lock_t spa_config_lock[SCL_LOCKS]; /* config changes */
 	refcount_t	spa_refcount;		/* number of opens */
+#ifndef sun
+	boolean_t	spa_splitting_newspa;	/* creating new spa in split */
+#endif
 };
 
 extern char *spa_config_path;

module/zfs/spa.c

@@ -5105,8 +5105,15 @@ spa_vdev_split_mirror(spa_t *spa, char *newname, nvlist_t *config,
 	spa_activate(newspa, spa_mode_global);
 	spa_async_suspend(newspa);
 
+#ifndef sun
+	/* mark that we are creating new spa by splitting */
+	newspa->spa_splitting_newspa = B_TRUE;
+#endif
 	/* create the new pool from the disks of the original pool */
 	error = spa_load(newspa, SPA_LOAD_IMPORT, SPA_IMPORT_ASSEMBLE, B_TRUE);
+#ifndef sun
+	newspa->spa_splitting_newspa = B_FALSE;
+#endif
 	if (error)
 		goto out;
 

module/zfs/vdev_iokit.c

@@ -151,7 +151,7 @@ vdev_iokit_open(vdev_t *vd, uint64_t *size,
 
 	/* When creating or splitting pools, don't validate guid */
 	if (vd->vdev_spa->spa_load_state != SPA_LOAD_NONE &&
-	    vd->vdev_spa->spa_config_splitting == 0) {
+	    vd->vdev_spa->spa_splitting_newspa != B_TRUE) {
 		checkguid = vd->vdev_guid;
 	}