On Mon, Jul 13, 2015 at 05:05:00PM +0200, Jan Kara wrote: > So if this is a writeable fault and we race with truncate, we can leave > stale blocks beyond i_size, can't we? Ah, looking at dax_insert_mapping() > this seems to be a documented quirk of DAX mmap code. Would be worth > mentioning here as well so that people don't wonder... Thanks! - /* Guard against a race with truncate */ + /* + * If a truncate happened while we were allocating blocks, we may + * leave blocks allocated to the file that are beyond EOF. We can't + * take i_mutex here, so just leave them hanging; they'll be freed + * when the file is deleted. + */ is what I'll commit. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>