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vsock: use new wait API for vsock_stream_sendmsg()

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As reported by Michal, vsock_stream_sendmsg() could still
sleep at vsock_stream_has_space() after prepare_to_wait():

  vsock_stream_has_space
    vmci_transport_stream_has_space
      vmci_qpair_produce_free_space
        qp_lock
          qp_acquire_queue_mutex
            mutex_lock

Just switch to the new wait API like we did for commit
d9dc8b0f8b ("net: fix sleeping for sk_wait_event()").

Reported-by: Michal Kubecek <mkubecek@suse.cz>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
WANG Cong 2017-05-19 11:21:59 -07:00 committed by David S. Miller
parent 72ccc471e1
commit 499fde662f
1 changed files with 8 additions and 13 deletions
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21
net/vmw_vsock/af_vsock.c
View File

@ -1540,8 +1540,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
long timeout;
int err;
struct vsock_transport_send_notify_data send_data;
DEFINE_WAIT(wait);
DEFINE_WAIT_FUNC(wait, woken_wake_function);
sk = sock->sk;
vsk = vsock_sk(sk);
@ -1584,11 +1583,10 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
if (err < 0)
goto out;
while (total_written < len) {
ssize_t written;
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
add_wait_queue(sk_sleep(sk), &wait);
while (vsock_stream_has_space(vsk) == 0 &&
sk->sk_err == 0 &&
!(sk->sk_shutdown & SEND_SHUTDOWN) &&
@ -1597,33 +1595,30 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
/* Don't wait for non-blocking sockets. */
if (timeout == 0) {
err = -EAGAIN;
finish_wait(sk_sleep(sk), &wait);
remove_wait_queue(sk_sleep(sk), &wait);
goto out_err;
}
err = transport->notify_send_pre_block(vsk, &send_data);
if (err < 0) {
finish_wait(sk_sleep(sk), &wait);
remove_wait_queue(sk_sleep(sk), &wait);
goto out_err;
}
release_sock(sk);
timeout = schedule_timeout(timeout);
timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
lock_sock(sk);
if (signal_pending(current)) {
err = sock_intr_errno(timeout);
finish_wait(sk_sleep(sk), &wait);
remove_wait_queue(sk_sleep(sk), &wait);
goto out_err;
} else if (timeout == 0) {
err = -EAGAIN;
finish_wait(sk_sleep(sk), &wait);
remove_wait_queue(sk_sleep(sk), &wait);
goto out_err;
}
prepare_to_wait(sk_sleep(sk), &wait,
TASK_INTERRUPTIBLE);
}
finish_wait(sk_sleep(sk), &wait);
remove_wait_queue(sk_sleep(sk), &wait);
/* These checks occur both as part of and after the loop
* conditional since we need to check before and after