On Mon, May 02, 2011 at 06:23:34PM +0200, Jan Kara wrote: > But why should it block when xfs_wait_for_freeze() gets called before > freeze_super() gets called? The other thread calls freeze_super() just > after xfs_wait_for_freeze() in thread 1 and before _xfs_trans_alloc() gets > called. Or am I missing some serialization somewhere? Oh, now I get the race window you mean. It's the single instruction window between doing the frozen check and incrementing m_active_trans. Yes, that one looks real, although very unlikely to hit. Could be fixed relatively easily by moving the check after the increment. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html