From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Ilya Maximets <i.maximets@samsung.com>
Cc: dev@dpdk.org, Huawei Xie <huawei.xie@intel.com>,
Dyasly Sergey <s.dyasly@samsung.com>,
Heetae Ahn <heetae82.ahn@samsung.com>,
Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [dpdk-dev] [PATCH] vhost: fix connect hang in client mode
Date: Thu, 21 Jul 2016 17:37:14 +0800 [thread overview]
Message-ID: <20160721093714.GD28708@yliu-dev.sh.intel.com> (raw)
In-Reply-To: <1469089275-15209-1-git-send-email-i.maximets@samsung.com>
On Thu, Jul 21, 2016 at 11:21:15AM +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")
Thanks for spotting and fixing yet another bug!
>
> +static int
> +vhost_user_connect_nonblock(int fd, struct sockaddr *un, size_t sz)
I don't quite understand why this is needed: connect() with O_NONBLOCK
flag set is not enough?
--yliu
next prev parent reply other threads:[~2016-07-21 9:33 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-21 8:21 Ilya Maximets
2016-07-21 9:37 ` Yuanhan Liu [this message]
2016-07-21 9:45 ` Ilya Maximets
2016-07-21 10:13 ` Yuanhan Liu
2016-07-21 10:37 ` Ilya Maximets
2016-07-21 11:14 ` Ilya Maximets
2016-07-21 11:40 ` Yuanhan Liu
2016-07-21 12:10 ` Ilya Maximets
2016-07-21 12:13 ` Ilya Maximets
2016-07-21 12:35 ` Yuanhan Liu
2016-07-21 12:42 ` Ilya Maximets
2016-07-21 12:58 ` Yuanhan Liu
2016-07-21 12:58 ` Ilya Maximets
2016-07-21 13:10 ` Yuanhan Liu
2016-07-21 11:12 ` [dpdk-dev] [PATCH v2] " Ilya Maximets
2016-07-21 13:19 ` [dpdk-dev] [PATCH v3] " Ilya Maximets
2016-07-21 13:35 ` Yuanhan Liu
2016-07-21 13:43 ` Ilya Maximets
2016-07-21 13:56 ` Yuanhan Liu
2016-07-21 22:21 ` Thomas Monjalon
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