Re: [PATCH] cgroup/cpuset: prevent overlapping local and remote partition creation

[Hui Peng]

Hi Guopeng,

On Sun, Sep 20, 2026 at 02:30:23PM +0800, Guopeng Zhang wrote:
> Should this return PERR_NOCPUS instead?
>
> +	if (cpumask_intersects(tmp->new_cpus, subpartitions_cpus))
> +		return PERR_NOCPUS;
>
...
> Would using PERR_NOCPUS here be more appropriate? This would keep the
> initial remote-partition enable path consistent with the CPU update path
> for an existing remote partition, and it also seems to describe the
> failure more accurately: the CPU itself is not invalid, but has already
> been allocated to another partition, so the parent can no longer
> distribute it downstream.

Agreed, returning PERR_NOCPUS when tmp->new_cpus intersects
subpartitions_cpus is much more accurate and keeps remote_partition_enable()
consistent with remote_cpus_update(). I have updated this in v2.

Thanks,
Hui