On Sat, 2016-10-29 at 19:06 +0200, Andrey Konovalov wrote:

Hi Cong,

Tested with your patch, still getting a warning, though it's a little different:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 3876 at kernel/sched/core.c:7724
__might_sleep+0x14c/0x1a0 kernel/sched/core.c:7719
do not call blocking ops when !TASK_RUNNING; state=1 set at
[<ffffffff811f5a5c>] prepare_to_wait+0xbc/0x210
kernel/sched/wait.c:178
Modules linked in:

This looks like the following patch is needed, can you test it ?
Thanks !

diff --git a/net/dccp/output.c b/net/dccp/output.c
index b66c84db0766..74d8583a0d52 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c

@@ -228,6 +228,7 @@ static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay)
 
 	remaining = schedule_timeout(delay);
 
+	sched_annotate_sleep();
 	lock_sock(sk);
 	sk->sk_write_pending--;
 	finish_wait(sk_sleep(sk), &wait);