[etherlab-users] INFO: task EtherCAT-EoE:4263 blocked for more than 120 seconds

[Bilko AS, Oguz Dilmac]

Hi,

We are moving from RTAI kernel space (2.6.32 32 bit kernel) application 
to PREEMPT-RT user space application. We are using Gavin's patch set on 
kernel 4.9.130 64bit kernel.

After around 15 hours of testing with servo drives, we see these kernel 
messages and our cyclic task hangs:

[62495.878833] INFO: task EtherCAT-EoE:4263 blocked for more than 120 
seconds.
[62495.878848]       Tainted: G           OE   4.9.130-rt125 #2
[62495.878855] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" 
disables this message.
[62495.878861] EtherCAT-EoE    D    0  4263      2 0x00000000
[62495.878872]  ffff8a26b5b24200 ffff8a26b5b24200 ffff8a26bfc9cd40 
ffff8a26b7175a00
[62495.878885]  ffff8a26b3da5a00 ffffaf52019bfd48 ffffffffba6cb64b 
00ffaf52019bfd70
[62495.878923]  ffff8a26bfc9cd40 ffffaf52019bfd50 ffff8a26b3da5a00 
ffff8a26b3e56080
[62495.878934] Call Trace:
[62495.878949]  [<ffffffffba6cb64b>] ? __schedule+0x24b/0x580
[62495.878956]  [<ffffffffba6cb9bd>] schedule+0x3d/0xd0
[62495.878962]  [<ffffffffba6ce85b>] schedule_timeout+0x29b/0x420
[62495.878969]  [<ffffffffba6ccf96>] __down+0x76/0xc0
[62495.878977]  [<ffffffffb9eb6d00>] ? cpu_cgroup_can_attach+0x80/0xb0
[62495.878984]  [<ffffffffb9ede2c1>] down+0x41/0x50
[62495.879014]  [<ffffffffc0696d06>] ec_master_eoe_thread+0xb6/0x210 
[ec_master]
[62495.879039]  [<ffffffffc0696c50>] ? ecrt_master_reset+0x40/0x40 
[ec_master]
[62495.879045]  [<ffffffffb9eaf1a8>] kthread+0xe8/0x100
[62495.879052]  [<ffffffffb9eaf0c0>] ? kthread_park+0x60/0x60
[62495.879057]  [<ffffffffba6d0477>] ret_from_fork+0x57/0x70

We didn't have such an error with RTAI.

What can I check?

Best regards,

Oguz.

-- 
Oguz Dilmac
ARGE Bolumu

Bilko AS, R&D Department
====================================
Perpa Ticaret Merkezi B Blok Kat 11 Nr. 1740
TR-34384 Okmeydani Istanbul Turkey
Tel : +90 212 220 07 40  Fax :   +90 212 210 47 01
e-mail : odilmac at bilko-automation.com
web site : http://www.bilko-automation.com