The patch titled Subject: mm: warn if pg_data_t isn't initialized with zero has been removed from the -mm tree. Its filename was mm-warn-if-pg_data_t-isnt-initialized-with-zero.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Minchan Kim <minchan@xxxxxxxxxx> Subject: mm: warn if pg_data_t isn't initialized with zero Warn if memory-hotplug/boot code doesn't initialize pg_data_t with zero when it is allocated. Arch code and memory hotplug already initiailize pg_data_t. So this warning should never happen. I select fields randomly near the beginning, middle and end of pg_data_t for checking. This patch isn't for performance but for removing initialization code which is necessary to add whenever we adds new field to pg_data_t or zone. Firstly, Andrew suggested clearing out of pg_data_t in MM core part but Tejun doesn't like it because in the future, some archs can initialize some fields in arch code and pass them into general MM part so blindly clearing it out in mm core part would be very annoying. Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 3 +++ 1 file changed, 3 insertions(+) diff -puN mm/page_alloc.c~mm-warn-if-pg_data_t-isnt-initialized-with-zero mm/page_alloc.c --- a/mm/page_alloc.c~mm-warn-if-pg_data_t-isnt-initialized-with-zero +++ a/mm/page_alloc.c @@ -4515,6 +4515,9 @@ void __paginginit free_area_init_node(in { pg_data_t *pgdat = NODE_DATA(nid); + /* pg_data_t should be reset to zero when it's allocated */ + WARN_ON(pgdat->nr_zones || pgdat->node_start_pfn || pgdat->classzone_idx); + pgdat->node_id = nid; pgdat->node_start_pfn = node_start_pfn; calculate_node_totalpages(pgdat, zones_size, zholes_size); _ Patches currently in -mm which might be from minchan@xxxxxxxxxx are origin.patch mm-remove-__gfp_no_kswapd.patch remove-__gfp_no_kswapd-fixes-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html