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Then per my understanding single > > READ_ONCE() within NAPI was sufficient, the one that makes the decision > > which Rx routine should be called (zc or standard one). Given that bh are > > disabled and updater respects RCU grace period IMHO pointer is valid for > > current NAPI cycle. > > So if we are already in the af_xdp handler, and update patch sets pool > to NULL - the af_xdp handler will be fine with the pool becoming NULL? > I guess it may be fine, it's just quite odd to call the function called > _ONCE() multiple times.. Update path before NULLing pool will go through rcu grace period, stop napis, disable irqs, etc. Running napi won't be exposed to nulled pool in such case. >