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
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