On Tue 02-01-18 16:55:46, Anshuman Khandual wrote: > On 12/08/2017 09:45 PM, Michal Hocko wrote: > > From: Michal Hocko <mhocko@xxxxxxxx> > > > > do_pages_move is supposed to move user defined memory (an array of > > addresses) to the user defined numa nodes (an array of nodes one for > > each address). The user provided status array then contains resulting > > numa node for each address or an error. The semantic of this function is > > little bit confusing because only some errors are reported back. Notably > > migrate_pages error is only reported via the return value. This patch > > It does report back the migration failures as well. In new_page_node > there is '*result = &pm->status' which going forward in unmap_and_move > will hold migration error or node ID of the new page. > > newpage = get_new_page(page, private, &result); > ............ > if (result) { > if (rc) > *result = rc; > else > *result = page_to_nid(newpage); > } > This is true, except the user will not get this information. Have a look how we do not copy status on error up in the do_pages_move layer. -- Michal Hocko SUSE Labs -- 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>