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i < cmap->map.max_entries; i++) { > struct bpf_cpu_map_entry *rcpu; > > - rcpu = READ_ONCE(cmap->cpu_map[i]); > + rcpu = rcu_dereference_check(cmap->cpu_map[i], > + rcu_read_lock_bh_held()); Is rcu_read_lock_bh_held() true during map_free()? [ ... ] > @@ -149,7 +152,8 @@ static int xsk_map_update_elem(struct bpf_map *map, void *key, void *value, > u64 map_flags) > { > struct xsk_map *m = container_of(map, struct xsk_map, map); > - struct xdp_sock *xs, *old_xs, **map_entry; > + struct xdp_sock __rcu **map_entry; > + struct xdp_sock *xs, *old_xs; > u32 i = *(u32 *)key, fd = *(u32 *)value; > struct xsk_map_node *node; > struct socket *sock; > @@ -179,7 +183,7 @@ static int xsk_map_update_elem(struct bpf_map *map, void *key, void *value, > } > > spin_lock_bh(&m->lock); > - old_xs = READ_ONCE(*map_entry); > + old_xs = rcu_dereference_check(*map_entry, rcu_read_lock_bh_held()); Is it actually protected by the m->lock at this point? [ ... ] > void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs, > - struct xdp_sock **map_entry) > + struct xdp_sock __rcu **map_entry) > { > spin_lock_bh(&map->lock); > - if (READ_ONCE(*map_entry) == xs) { > - WRITE_ONCE(*map_entry, NULL); > + if (rcu_dereference(*map_entry) == xs) { nit. rcu_access_pointer()? > + rcu_assign_pointer(*map_entry, NULL); > xsk_map_sock_delete(xs, map_entry); > } > spin_unlock_bh(&map->lock); > -- > 2.31.1 >