Re: [PATCH] mm: take memory hotplug lock within numa_zonelist_order_handler()

From: Michal Hocko
Date: Wed Jul 26 2017 - 07:31:23 EST


On Wed 26-07-17 13:17:38, Heiko Carstens wrote:
[...]
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 6d30e914afb6..fc32aa81f359 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -4891,9 +4891,11 @@ int numa_zonelist_order_handler(struct ctl_table *table, int write,
> NUMA_ZONELIST_ORDER_LEN);
> user_zonelist_order = oldval;
> } else if (oldval != user_zonelist_order) {
> + mem_hotplug_begin();
> mutex_lock(&zonelists_mutex);
> build_all_zonelists(NULL, NULL);
> mutex_unlock(&zonelists_mutex);
> + mem_hotplug_done();
> }
> }
> out:

Please note that this code has been removed by
http://lkml.kernel.org/r/20170721143915.14161-2-mhocko@xxxxxxxxxxx It
will get to linux-next as soon as Andrew releases a new version mmotm
tree.

--
Michal Hocko
SUSE Labs