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Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, "Paul E . McKenney" References: <20221202052847.2623997-1-edumazet@google.com> From: Dmitry Safonov In-Reply-To: <20221202052847.2623997-1-edumazet@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 12/2/22 05:28, Eric Dumazet wrote: > kfree_rcu(1-arg) should be avoided as much as possible, > since this is only possible from sleepable contexts, > and incurr extra rcu barriers. > > I wish the 1-arg variant of kfree_rcu() would > get a distinct name, like kfree_rcu_slow() > to avoid it being abused. Thanks again! > Fixes: 459837b522f7 ("net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction") > Signed-off-by: Eric Dumazet > Cc: Dmitry Safonov > Cc: Paul E. McKenney Reviewed-by: Dmitry Safonov > --- > net/ipv4/tcp_ipv4.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c > index 7fae586405cfb10011a0674289280bf400dfa8d8..8320d0ecb13ae1e3e259f3c13a4c2797fbd984a5 100644 > --- a/net/ipv4/tcp_ipv4.c > +++ b/net/ipv4/tcp_ipv4.c > @@ -1245,7 +1245,7 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, > > md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); > rcu_assign_pointer(tp->md5sig_info, NULL); > - kfree_rcu(md5sig); > + kfree_rcu(md5sig, rcu); > return -EUSERS; > } > } > @@ -1271,7 +1271,7 @@ int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, > md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); > net_warn_ratelimited("Too many TCP-MD5 keys in the system\n"); > rcu_assign_pointer(tp->md5sig_info, NULL); > - kfree_rcu(md5sig); > + kfree_rcu(md5sig, rcu); > return -EUSERS; > } > } -- Dmitry