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> > > - synchronize_rcu(); > > > - kfree(peer); > > > + kfree_rcu(peer); > > The kfree_rcu(peer) should be kfree_rcu(peer, rcu), due to the rcu_head > member named rcu in fwtty_peer. Oh, huh. What happens if you don't pas the "rcu" parameter? I see there is a similar instance in ext4_apply_quota_options(). kfree_rcu(qname); regards, dan carpenter