Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 19 Sep 2005 09:52:40 +0530 | From | Srivatsa Vaddagiri <> | Subject | Re: PATCH: Fix race in cpu_down (hotplug cpu) |
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On Mon, Sep 19, 2005 at 01:28:38PM +1000, Nigel Cunningham wrote: > There is a race condition in taking down a cpu (kernel/cpu.c::cpu_down). > A cpu can already be idling when we clear its online flag, and we do not > force the idle task to reschedule. This results in __cpu_die timing out.
"when we clear its online flag" - This happens in take_cpu_down in the context of stopmachine thread. take_cpu_down also ensures that idle thread runs when it returns (sched_idle_next). So when idle thread runs, it should notice that it is offline and invoke play_dead. So I don't understand why __cpu_die should time out.
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Thanks and Regards, Srivatsa Vaddagiri, Linux Technology Center, IBM Software Labs, Bangalore, INDIA - 560017 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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