[CentOS-devel] ssh block bug in CentOS 6.4

Wed Oct 30 00:04:21 UTC 2013
jupiter <jupiter.hce at gmail.com>

Hi,

I have recently found a problem of randomly being blocked by ssh
connection to a 64 bit CentOS 6.4 virtual machine, the dmesg shown
following error:

..........

INFO: task gnome-settings-:16976 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
gnome-setting D 0000000000000000     0 16976      1 0x00000080
 ffff8800dc3e5dd8 0000000000000082 0000000000000000 ffff8800be54faf0
 ffff8800dc3e5d98 ffff8800daf07540 ffff8800daf07540 ffff8800daf07540
 ffff8800daf07af8 ffff8800dc3e5fd8 000000000000fb88 ffff8800daf07af8
Call Trace:
 [<ffffffff811a1bc0>] ? mntput_no_expire+0x30/0x110
 [<ffffffff8150efbe>] __mutex_lock_slowpath+0x13e/0x180
 [<ffffffff8150ee5b>] mutex_lock+0x2b/0x50
 [<ffffffff8118e890>] lookup_create+0x30/0xd0
 [<ffffffff81192589>] sys_symlinkat+0x99/0x120
 [<ffffffff81186b4e>] ? vfs_lstat+0x1e/0x20
 [<ffffffff81186b74>] ? sys_newlstat+0x24/0x50
 [<ffffffff810dc8f7>] ? audit_syscall_entry+0x1d7/0x200
 [<ffffffff81192626>] sys_symlink+0x16/0x20
 [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b
--------

Searched from Internet and found similar bug report for Fedora 19
declared the issue to a blocker. It seems to me that the bug I
encountered is the same in Fedora 19. While Fedora has a workaround
patch, I am not clear if that bug has been reported to CentOS dev and
if you have a patch as well? Please advice and update.

Thank you.

Kind regards,

jupiter