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The donor does not execute there, and its original execution CPU remains recorded in wake_cpu. set_task_cpu() warns unconditionally for migration-disabled tasks, so a subsequent proxy migration or the wakeup path returning the donor home triggers a false positive. Moving a blocked scheduling context does not violate the migration-disabled execution context. Exclude blocked proxy donors from the warning. The proxy wakeup path restores an executable placement before clearing the blocked state. This is a preparatory fix for enabling proxy execution together with sched_ext. Signed-off-by: Andrea Righi --- kernel/sched/core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 3cc6fb1d20547..a0e813abddc28 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3376,7 +3376,13 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) */ WARN_ON_ONCE(!cpu_online(new_cpu)); - WARN_ON_ONCE(is_migration_disabled(p)); + /* + * Proxy execution can move a blocked task's scheduling context to any + * CPU without moving its migration-disabled execution context. The + * wakeup path will return the task to a CPU where it can execute. + */ + WARN_ON_ONCE(is_migration_disabled(p) && + !(sched_proxy_exec() && p->is_blocked)); trace_sched_migrate_task(p, new_cpu); -- 2.55.0