I have a question of the call path init/main.c:
init/main.c: start_kernel() ->
kernel/events/core.c: perf_pmu_register() ->
kernel/events/core.c: perf_event_init() ->
kernel/events/core.c: pmu_dev_alloc()

In this call path, start_kernel() calls local_irq_disable() to disable the interrupt; perf_pmu_register() calls mutex_lock() and idr_alloc(GFP_KERNEL), and they can sleep;
pmu_dev_alloc() calls kzalloc(GFP_KERNEL), and it can sleep.

In my opinion, this code may sleep with interrupts are disabled.
I wonder why this code is okay?

Best wishes,
Jia-Ju Bai

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