4.4-stable review patch. If anyone has any objections, please let me know.
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From: WANG Cong xiyou.wangcong@gmail.com
commit 499fde662f1957e3cb8d192a94a099ebe19c714b upstream.
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 d9dc8b0f8b4e ("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 Cc: "Jorgen S. Hansen" jhansen@vmware.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/vmw_vsock/af_vsock.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-)
--- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1512,8 +1512,7 @@ static int vsock_stream_sendmsg(struct s 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); @@ -1556,11 +1555,10 @@ static int vsock_stream_sendmsg(struct s 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) && @@ -1569,33 +1567,30 @@ static int vsock_stream_sendmsg(struct s /* 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