This is a note to let you know that I've just added the patch titled vsock: use new wait API for vsock_stream_sendmsg() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: vsock-use-new-wait-api-for-vsock_stream_sendmsg.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 499fde662f1957e3cb8d192a94a099ebe19c714b Mon Sep 17 00:00:00 2001 From: WANG Cong <xiyou.wangcong@xxxxxxxxx> Date: Fri, 19 May 2017 11:21:59 -0700 Subject: vsock: use new wait API for vsock_stream_sendmsg() From: WANG Cong <xiyou.wangcong@xxxxxxxxx> 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@xxxxxxx> Cc: Stefan Hajnoczi <stefanha@xxxxxxxxxx> Cc: Jorgen Hansen <jhansen@xxxxxxxxxx> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Cc: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxxxxxxx> Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Cc: "Jorgen S. Hansen" <jhansen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 Patches currently in stable-queue which might be from xiyou.wangcong@xxxxxxxxx are queue-4.4/vsock-use-new-wait-api-for-vsock_stream_sendmsg.patch queue-4.4/ipv6-only-call-ip6_route_dev_notify-once-for-netdev_unregister.patch