On Mon 26-09-22 12:08:00, Florian Westphal wrote: > Michal Hocko <mhocko@xxxxxxxx> wrote: > > + old_tbl = rht_dereference_rcu(ht->tbl, ht); > > + size = tbl->size; > > + > > + data = ERR_PTR(-EBUSY); > > + > > + if (rht_grow_above_75(ht, tbl)) > > + size *= 2; > > + /* Do not schedule more than one rehash */ > > + else if (old_tbl != tbl) > > + return data; > > + > > + data = ERR_PTR(-ENOMEM); > > + > > + rcu_read_unlock(); > > + new_tbl = bucket_table_alloc(ht, size, GFP_KERNEL); > > + rcu_read_lock(); > > I don't think this is going to work, there can be callers that > rely on rcu protected data structures getting free'd. The caller of this function drops RCU for each retry, why should be the called function any special? -- Michal Hocko SUSE Labs
