On Tue, 4 Oct 2016, tip-bot for Ingo Molnar wrote: > The original change widens a preempt-off section, to avoid a seemingly unsafe > smp_processor_id() use. > > During review I overlooked two facts: > > - The code to calls a non-trivial function callback: > > ht->park(td->cpu); > > ... which might (and does occasionally) sleep, triggering the warning. > > - More importantly, as pointed out by Peter Zijlstra, using > smp_processor_id() in that context is safe, if it's done from > a kernel thread that is pinned to a single CPU - which is the > case here. > > So revert to the original code that enables preemption sooner. > > Reported-by: kernel test robot <xiaolong.ye@xxxxxxxxx> > Acked-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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