On Mon, Mar 30, 2020 at 05:48:42AM -0700, Matthew Wilcox wrote: >On Mon, Mar 30, 2020 at 12:36:39PM +0000, Wei Yang wrote: >> If an entry is at the last level, whose parent's shift is 0, it is not >> expected to be a node. We can just leverage the xa_is_node() check to >> break the loop instead of check shift additionally. > >I know you didn't run the test suite after making this change. Well, I got your point finally. From commit 76b4e5299565 ('XArray: Permit storing 2-byte-aligned pointers'), xa_is_node() will not be *ACURATE*. Those 2-byte align pointers will be treated as node too. Well, I found another thing, but not sure whether you have fixed this or not. If applying following change @@ -1461,6 +1461,11 @@ static void check_align_1(struct xarray *xa, char *name) GFP_KERNEL) != 0); XA_BUG_ON(xa, id != i); } + XA_STATE_ORDER(xas, xa, 0, 0); + entry = xas_find_conflict(&xas); xa_for_each(xa, index, entry) XA_BUG_ON(xa, xa_is_err(entry)); xa_destroy(xa); We trigger an error message. The reason is the same. And we can fix this with the same approach in xas_find_conflict(). If you think this is the proper way, I would add a patch for this. -- Wei Yang Help you, Help me