Hi, all, We had backport the no-lru migration to linux-4.1, meanwhile change the ZS_MAX_ZSPAGE_ORDER to 3. Then we met a BUG_ON(!page[1]). It rarely happen, and presently, what I get is: [6823.316528s]obj=a160701f, obj_idx=15, class{size:2176,objs_per_zspage:15,pages_per_zspage:8} [...] [6823.316619s]BUG: failure at /home/ethan/kernel/linux-4.1/mm/zsmalloc.c:1458/zs_map_object()! ----> BUG_ON(!page[1]) It seems that we have allocated an object from a ZS_FULL group? (Actually, I do not get the inuse number of this zspage, which I am trying to.) And presently, I can not find why it happened. Any idea about it? Any comment is more than welcome! Thanks Yisheng Xie -- 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>