Re: [PATCH v3] vhost: fix connect hang in client mode

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Thu, Jul 21, 2016 at 04:19:35PM +0300, Ilya Maximets wrote:
> If something abnormal happened to QEMU, 'connect()' can block calling
> thread (e.g. main thread of OVS) forever or for a really long time.
> This can break whole application or block the reconnection thread.
> 
> Example with OVS:
> 
> 	ovs_rcu(urcu2)|WARN|blocked 512000 ms waiting for main to quiesce
> 	(gdb) bt
> 	#0  connect () from /lib64/libpthread.so.0
> 	#1  vhost_user_create_client (vsocket=0xa816e0)
> 	#2  rte_vhost_driver_register
> 	#3  netdev_dpdk_vhost_user_construct
> 	#4  netdev_open (name=0xa664b0 "vhost1")
> 	[...]
> 	#11 main
> 
> Fix that by setting non-blocking mode for client sockets for connection.
> 
> Fixes: 64ab701c3d1e ("vhost: add vhost-user client mode")
> 
> Signed-off-by: Ilya Maximets <i.maximets@samsung.com>

Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>

One help I'd like to ask is that I'd appriciate if you could do the test
to make sure that your 2 (latest) patches fix the two issues you reported.

You might have already done that; I just want to make sure.

Thanks.

	--yliu