Comment 0 for bug 1797202

[Impact]
The numa mask subset check can often lead to system hang or crash during CPU hotplug and system suspend operation if NUMA is disabled. This is mostly observed on HMP systems where the CPU compute capacities are different and ends up in different scheduler domains. Since cpumask_of_node is returned instead core_sibling, the scheduler is confused with incorrect cpumasks(e.g. one CPU in two different sched domains at the same time) on CPU hotplug.

[Fix]
The following patch fixes this issue:
e156ab71a974 arm64: topology: Avoid checking numa mask for scheduler MC selection

[Test]

[Regression Potential]