I'm on the same kernel
Linux sl 4.4.0-8-generic #23-Ubuntu SMP Wed Feb 24 20:45:30 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
and also have the tracefs mounted
0 ✓ serge@sl ~ $ grep debug /proc/self/mountinfo 74 19 0:7 / /sys/kernel/debug rw,relatime shared:26 - debugfs debugfs rw 44 74 0:9 / /sys/kernel/debug/tracing rw,relatime shared:29 - tracefs tracefs rw
but trusty (upstart-based) containers start fine for me, using lxc version 2.0.0~rc4+master~20160229-0647-0ubuntu1~xenial and lxd from git HEAD.
Very odd therefore that unmounting and re-mounting debugfs works for you...
Will try in a fresh vm.
I'm on the same kernel
Linux sl 4.4.0-8-generic #23-Ubuntu SMP Wed Feb 24 20:45:30 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
and also have the tracefs mounted
0 ✓ serge@sl ~ $ grep debug /proc/self/ mountinfo debug/tracing rw,relatime shared:29 - tracefs tracefs rw
74 19 0:7 / /sys/kernel/debug rw,relatime shared:26 - debugfs debugfs rw
44 74 0:9 / /sys/kernel/
but trusty (upstart-based) containers start fine for me, using lxc version 2.0.0~rc4+ master~ 20160229- 0647-0ubuntu1~ xenial and lxd from git HEAD.
Very odd therefore that unmounting and re-mounting debugfs works for you...
Will try in a fresh vm.