From 7cb001d4c4fa7e1cc1a55388a9544e160dddc610 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 17 May 2016 17:44:06 -0700 Subject: [PATCH] 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); } -- 2.20.1