Hello Yousef, On 03/07/2026 at 04:19:42 -07, Yousef Alhouseen <[email protected]> wrote:
> Hello Miquel, > > After ieee802154_unregister_hw() returns, the driver callbacks that > can replace phy->pib have been quiesced, and hwsim_del() has exclusive > ownership of the final teardown. The pointer is no longer being > fetched inside an RCU read-side critical section, so rcu_dereference() > is not appropriate there. That's right. > rcu_dereference_protected(phy->pib, 1) expresses that there can no > longer be a concurrent updater at that point; the protection condition > is the completed unregister rather than a locally held lock. The value > is only fetched so the final object can be passed to kfree_rcu(). While I believe this is indeed true, it actually feels slightly overkill since there is no updater anymore and, as far as I understand, the only thing that we need here is to get the pointer value for freeing, right? > rcu_access_pointer() would also be sufficient for that limited use if > you prefer it, and I can use that spelling in a v2. If you don't mind, I feel like rcu_access_pointer() is exactly what we need here. It is also more understandable, even though I agree in practice there are no differences in this case. Thanks, Miquèl
