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And, for PREEMPT_RCU=y configurations does this >> by directly calling rcu_momentary_eqs(). >> >> With PREEMPT_LAZY=y, however, we can have configurations with >> (PREEMPTION=y, PREEMPT_RCU=n), which means neither of the above >> can help. > > PREEMPTION=y, PREEMPT_RCU=n should not be possible. That's a statement. Is there an argument here? -- ankur