Re: [PATCH] mm/alloc: fallback to first node if the wanted node offline

From: Michal Hocko
Date: Fri Dec 07 2018 - 10:56:34 EST


On Fri 07-12-18 22:27:13, Pingfan Liu wrote:
[...]
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index 1308f54..4dc497d 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -754,18 +754,23 @@ void __init init_cpu_to_node(void)
> {
> int cpu;
> u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
> + int node, nr;
>
> BUG_ON(cpu_to_apicid == NULL);
> + nr = cpumask_weight(cpu_possible_mask);
> +
> + /* bring up all possible node, since dev->numa_node */
> + //should check acpi works for node possible,
> + for_each_node(node)
> + if (!node_online(node))
> + init_memory_less_node(node);

I suspect there is no change if you replace for_each_node by
for_each_node_mask(nid, node_possible_map)

here. If that is the case then we are probably calling
free_area_init_node too early. I do not see it yet though.
--
Michal Hocko
SUSE Labs