If we failed to setup hotplug state callbacks for mm/demotion:online in some corner cases, node_demotion will be left uninitialized. Invalid node might be returned from the next_demotion_node() when doing reclaim-based migration. Use kcalloc to allocate node_demotion to fix the issue. Fixes: ac16ec835314 ("mm: migrate: support multiple target nodes demotion") Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: "Huang, Ying" <ying.huang@xxxxxxxxx> --- mm/migrate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 97dfd1f4870d..dbd91fbdb127 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2534,9 +2534,9 @@ static int __init migrate_on_reclaim_init(void) { int ret; - node_demotion = kmalloc_array(nr_node_ids, - sizeof(struct demotion_nodes), - GFP_KERNEL); + node_demotion = kcalloc(nr_node_ids, + sizeof(struct demotion_nodes), + GFP_KERNEL); WARN_ON(!node_demotion); ret = cpuhp_setup_state_nocalls(CPUHP_MM_DEMOTION_DEAD, "mm/demotion:offline", -- 2.23.0