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never latch a torn view. */ >> + if (!data_race(cpumask_equal(cpu_present_mask, cpu_online_mask))) { >> + for_each_possible_cpu(cpu) >> + free_cpumask_var(snapshot[cpu]); >> + kfree(snapshot); >> + goto out; >> + } > > What about check snapshot against cpu_present_mask? Hi Wangyang, Thanks for the review. Both comments are valid - I will address them in the next revision.