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Fix this confusing naming, since much of the rest of the code > also relies on it being current. > > Specifically, both exec() and exit() callers use it with current as > the argument. When perf_event_exit_task_context() gets called by perf_event_free_task(): 1) task_ctx_sched_out(ctx) function should be avoided because the 'ctx' argument is of the (half baked)child task whereas task_ctx_sched_out() expects 'ctx' to be the context of 'current'. 2) Similarly, 'task' argument != 'current'. --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -13573,7 +13573,8 @@ static void perf_event_exit_task_context(struct task_struct *task, bool exit) * in. */ raw_spin_lock_irq(&ctx->lock); - task_ctx_sched_out(ctx, NULL, EVENT_ALL); + if (exit) + task_ctx_sched_out(ctx, NULL, EVENT_ALL); /* * Now that the context is inactive, destroy the task <-> ctx relation @@ -13582,7 +13583,7 @@ static void perf_event_exit_task_context(struct task_struct *task, bool exit) RCU_INIT_POINTER(task->perf_event_ctxp, NULL); put_ctx(ctx); /* cannot be last */ WRITE_ONCE(ctx->task, TASK_TOMBSTONE); - put_task_struct(current); /* cannot be last */ + put_task_struct(task); /* cannot be last */ clone_ctx = unclone_ctx(ctx); raw_spin_unlock_irq(&ctx->lock); Thanks, Ravi