From 7cb001d4c4fa7e1cc1a55388a9544e160dddc610 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 17 May 2016 17:44:06 -0700 Subject: [PATCH 1/4] scsi_tcp: block BH in TCP callbacks iscsi_sw_tcp_data_ready() and iscsi_sw_tcp_state_change() were using read_lock(&sk->sk_callback_lock) which is fine if caller disabled BH. TCP stack no longer has this requirement and can run from process context. Use read_lock_bh() variant to restore previous assumption. Ideally this code could use RCU instead... Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet Cc: Mike Christie Cc: Venkatesh Srinivas Acked-by: Mike Christie Signed-off-by: David S. Miller --- drivers/scsi/iscsi_tcp.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c index 2e4c82f8329c..ace4f1f41b8e 100644 --- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -131,10 +131,10 @@ static void iscsi_sw_tcp_data_ready(struct sock *sk) struct iscsi_tcp_conn *tcp_conn; read_descriptor_t rd_desc; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); conn = sk->sk_user_data; if (!conn) { - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); return; } tcp_conn = conn->dd_data; @@ -154,7 +154,7 @@ static void iscsi_sw_tcp_data_ready(struct sock *sk) /* If we had to (atomically) map a highmem page, * unmap it now. */ iscsi_tcp_segment_unmap(&tcp_conn->in.segment); - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); } static void iscsi_sw_tcp_state_change(struct sock *sk) @@ -165,10 +165,10 @@ static void iscsi_sw_tcp_state_change(struct sock *sk) struct iscsi_session *session; void (*old_state_change)(struct sock *); - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); conn = sk->sk_user_data; if (!conn) { - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); return; } session = conn->session; @@ -179,7 +179,7 @@ static void iscsi_sw_tcp_state_change(struct sock *sk) tcp_sw_conn = tcp_conn->dd_data; old_state_change = tcp_sw_conn->old_state_change; - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); old_state_change(sk); } From e1daca289a36965d923ec26647b5668e023eb0ac Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 17 May 2016 17:44:07 -0700 Subject: [PATCH 2/4] ocfs2/cluster: block BH in TCP callbacks TCP stack can now run from process context. Use read_lock_bh() variant to restore previous assumption. Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- fs/ocfs2/cluster/tcp.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c index 2d0acd6678fe..4238eb28889f 100644 --- a/fs/ocfs2/cluster/tcp.c +++ b/fs/ocfs2/cluster/tcp.c @@ -600,10 +600,11 @@ static void o2net_set_nn_state(struct o2net_node *nn, static void o2net_data_ready(struct sock *sk) { void (*ready)(struct sock *sk); + struct o2net_sock_container *sc; - read_lock(&sk->sk_callback_lock); - if (sk->sk_user_data) { - struct o2net_sock_container *sc = sk->sk_user_data; + read_lock_bh(&sk->sk_callback_lock); + sc = sk->sk_user_data; + if (sc) { sclog(sc, "data_ready hit\n"); o2net_set_data_ready_time(sc); o2net_sc_queue_work(sc, &sc->sc_rx_work); @@ -611,7 +612,7 @@ static void o2net_data_ready(struct sock *sk) } else { ready = sk->sk_data_ready; } - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); ready(sk); } @@ -622,7 +623,7 @@ static void o2net_state_change(struct sock *sk) void (*state_change)(struct sock *sk); struct o2net_sock_container *sc; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); sc = sk->sk_user_data; if (sc == NULL) { state_change = sk->sk_state_change; @@ -649,7 +650,7 @@ static void o2net_state_change(struct sock *sk) break; } out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); state_change(sk); } @@ -2012,7 +2013,7 @@ static void o2net_listen_data_ready(struct sock *sk) { void (*ready)(struct sock *sk); - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); ready = sk->sk_user_data; if (ready == NULL) { /* check for teardown race */ ready = sk->sk_data_ready; @@ -2039,7 +2040,7 @@ static void o2net_listen_data_ready(struct sock *sk) } out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); if (ready != NULL) ready(sk); } From 38036629cded6b96a9f9689758a88d067c4d4d44 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 17 May 2016 17:44:08 -0700 Subject: [PATCH 3/4] rds: tcp: block BH in TCP callbacks TCP stack can now run from process context. Use read_lock_bh(&sk->sk_callback_lock) variant to restore previous assumption. Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/rds/tcp_connect.c | 4 ++-- net/rds/tcp_listen.c | 4 ++-- net/rds/tcp_recv.c | 4 ++-- net/rds/tcp_send.c | 4 ++-- 4 files changed, 8 insertions(+), 8 deletions(-) diff --git a/net/rds/tcp_connect.c b/net/rds/tcp_connect.c index 49a3fcfed360..fb82e0a0bf89 100644 --- a/net/rds/tcp_connect.c +++ b/net/rds/tcp_connect.c @@ -43,7 +43,7 @@ void rds_tcp_state_change(struct sock *sk) struct rds_connection *conn; struct rds_tcp_connection *tc; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); conn = sk->sk_user_data; if (!conn) { state_change = sk->sk_state_change; @@ -69,7 +69,7 @@ void rds_tcp_state_change(struct sock *sk) break; } out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); state_change(sk); } diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index be263cdf268b..3fa367945105 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -166,7 +166,7 @@ void rds_tcp_listen_data_ready(struct sock *sk) rdsdebug("listen data ready sk %p\n", sk); - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); ready = sk->sk_user_data; if (!ready) { /* check for teardown race */ ready = sk->sk_data_ready; @@ -183,7 +183,7 @@ void rds_tcp_listen_data_ready(struct sock *sk) rds_tcp_accept_work(sk); out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); ready(sk); } diff --git a/net/rds/tcp_recv.c b/net/rds/tcp_recv.c index d75d8b56a9e3..c3196f9d070a 100644 --- a/net/rds/tcp_recv.c +++ b/net/rds/tcp_recv.c @@ -301,7 +301,7 @@ void rds_tcp_data_ready(struct sock *sk) rdsdebug("data ready sk %p\n", sk); - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); conn = sk->sk_user_data; if (!conn) { /* check for teardown race */ ready = sk->sk_data_ready; @@ -315,7 +315,7 @@ void rds_tcp_data_ready(struct sock *sk) if (rds_tcp_read_sock(conn, GFP_ATOMIC) == -ENOMEM) queue_delayed_work(rds_wq, &conn->c_recv_w, 0); out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); ready(sk); } diff --git a/net/rds/tcp_send.c b/net/rds/tcp_send.c index 2894e6095e3b..22d0f2020a79 100644 --- a/net/rds/tcp_send.c +++ b/net/rds/tcp_send.c @@ -180,7 +180,7 @@ void rds_tcp_write_space(struct sock *sk) struct rds_connection *conn; struct rds_tcp_connection *tc; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); conn = sk->sk_user_data; if (!conn) { write_space = sk->sk_write_space; @@ -200,7 +200,7 @@ void rds_tcp_write_space(struct sock *sk) queue_delayed_work(rds_wq, &conn->c_send_w, 0); out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); /* * write_space is only called when data leaves tcp's send queue if From b91083a45e4c41b8c952cf02ceb0ce16f0b1b9b1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 17 May 2016 17:44:09 -0700 Subject: [PATCH 4/4] tipc: block BH in TCP callbacks TCP stack can now run from process context. Use read_lock_bh(&sk->sk_callback_lock) variant to restore previous assumption. Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog") Signed-off-by: Eric Dumazet Cc: Jon Maloy Cc: Ying Xue Signed-off-by: David S. Miller --- net/tipc/server.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/tipc/server.c b/net/tipc/server.c index 7a0af2dc0406..272d20a795d5 100644 --- a/net/tipc/server.c +++ b/net/tipc/server.c @@ -138,28 +138,28 @@ static void sock_data_ready(struct sock *sk) { struct tipc_conn *con; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); con = sock2con(sk); if (con && test_bit(CF_CONNECTED, &con->flags)) { conn_get(con); if (!queue_work(con->server->rcv_wq, &con->rwork)) conn_put(con); } - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); } static void sock_write_space(struct sock *sk) { struct tipc_conn *con; - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); con = sock2con(sk); if (con && test_bit(CF_CONNECTED, &con->flags)) { conn_get(con); if (!queue_work(con->server->send_wq, &con->swork)) conn_put(con); } - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); } static void tipc_register_callbacks(struct socket *sock, struct tipc_conn *con)