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 <edumazet@google.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Venkatesh Srinivas <venkateshs@google.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 2e4c82f..ace4f1f 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -131,10 +131,10 @@
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 @@
/* 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 @@
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 @@
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);
}