diff --git a/lustre/mdt/mdt_handler.c b/lustre/mdt/mdt_handler.c index 3640dc98fdb468047c581b29b90f80af03687f16..42a6e78200e203952295ec520eeef28342149b20 100644 --- a/lustre/mdt/mdt_handler.c +++ b/lustre/mdt/mdt_handler.c @@ -3811,6 +3811,19 @@ static void mdt_fini(const struct lu_env *env, struct mdt_device *m) struct obd_device *obd = m->mdt_md_dev.md_lu_dev.ld_obd; ENTRY; + /* At this point, obd exports might still be on the "obd_zombie_exports" + * list, and obd_zombie_impexp_thread() is trying to destroy them. + * We wait a little bit until all exports (except the self-export) + * have been destroyed, because the whole mdt stack might be accessed + * in mdt_destroy_export(). This will not be a long time, maybe one or + * two seconds are enough. This is not a problem while umounting. + * + * The three references that should be remaining are the + * obd_self_export and the attach and setup references. + */ + while (atomic_read(&obd->obd_refcount) > 3) + cfs_schedule_timeout(CFS_TASK_UNINT, cfs_time_seconds(1)); + ping_evictor_stop(); target_recovery_fini(obd);