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Signed-off-by: Andrea Righi --- kernel/sched/core.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 3cc6fb1d20547..8a3eecc7caf5d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6936,6 +6936,20 @@ find_proxy_task(struct rq *rq, struct task_struct *donor, struct rq_flags *rf) */ if (curr_in_chain) return proxy_resched_idle(rq); + /* + * Tasks pinned to a single CPU (per-CPU kthreads via + * kthread_bind(), tasks under migrate_disable()) cannot + * be moved to @owner_cpu. proxy_migrate_task() uses + * __set_task_cpu() which would silently violate the + * pinning and leave the task to run on a CPU outside + * its cpus_ptr once it is unblocked. Deactivate it on + * this CPU; the owner running elsewhere will wake @p + * back up when the mutex becomes available. + */ + if (p->nr_cpus_allowed == 1 || is_migration_disabled(p)) { + __clear_task_blocked_on(p, NULL); + goto deactivate; + } goto migrate_task; } -- 2.55.0