On NUMA systems with dynamic processors, the content of the cpumask may change over time. As new processors are added via DLPAR operations, workqueues are created for them. This patch ensures that the pools created for new workqueues will be initialized with a cpumask before the first worker is created, attached, and woken up. If the mask is not set up, then the kernel will crash when 'wakeup_process' is unable to find a valid CPU to which to assign the new worker.
Signed-off-by: Michael Bringmann <[email protected]> --- diff --git a/kernel/workqueue.c b/kernel/workqueue.c index c74bf39..6091069 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -3366,6 +3366,8 @@ static struct worker_pool *get_unbound_pool(const struct workqueue_attrs *attrs) copy_workqueue_attrs(pool->attrs, attrs); pool->node = target_node; + cpumask_copy(pool->attrs->cpumask, cpumask_of(smp_processor_id())); + /* * no_numa isn't a worker_pool attribute, always clear it. See * 'struct workqueue_attrs' comments for detail.
