Re: [PATCH] s390: set NODES_SHIFT=0 when NUMA=n

[Heiko Carstens]

On Tue, Jun 09, 2020 at 09:45:01PM -0400, Qian Cai wrote:
> When NUMA=n and nr_node_ids=2, in apply_wqattrs_prepare(), it has,
> 
> for_each_node(node) {
> 	if (wq_calc_node_cpumask(...
> 
> where it will trigger a booting warning,
> 
> WARNING: workqueue cpumask: online intersect > possible intersect
> 
> because it found 2 nodes and wq_numa_possible_cpumask[1] is an empty
> cpumask. NUMA=y has no such problem because node_possible_map will be
> initialized properly containing only node 0. Fix it by setting
> NODES_SHIFT=0 when NUMA=n.
> 
> Fixes: 701dc81e7412 ("s390/mm: remove fake numa support")
> Signed-off-by: Qian Cai <cai@xxxxxx>
> ---
>  arch/s390/Kconfig | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Thanks! However I committed a different solution. Hope you don't mind: