On Wed, Aug 19, 2020 at 08:39:13PM +1000, Alexey Kardashevskiy wrote: > > or current upstream? > > The upstream 18445bf405cb (13 hours old) also shows the problem. Yours > 1/2 still fixes it. Afaict that just reduces the window. Isn't the problem that: arch/powerpc/kernel/exceptions-64e.S START_EXCEPTION(perfmon); NORMAL_EXCEPTION_PROLOG(0x260, BOOKE_INTERRUPT_PERFORMANCE_MONITOR, PROLOG_ADDITION_NONE) EXCEPTION_COMMON(0x260) INTS_DISABLE # RECONCILE_IRQ_STATE # TRACE_DISABLE_INTS # TRACE_WITH_FRAME_BUFFER(trace_hardirqs_off) # # but we haven't done nmi_enter() yet... whoopsy CHECK_NAPPING() addi r3,r1,STACK_FRAME_OVERHEAD bl performance_monitor_exception # perf_irq() # perf_event_interrupt # __perf_event_interrupt # nmi_enter() That is, afaict your entry code is buggered.
