This problem can be reproduced on 14.04 LTS (3.13.0-76-generic).
But because the bug has fixed in upstream kernel since 4.2, the problem is not caused on 15.10 (4.2.0-30-generic).
I have not try to reproduce on 12.04 LTS yet, but if the kernel version is earlier than 4.2, the problem will be reproduced probably.
Hi,
Thank you for the reply.
This problem can be reproduced on 14.04 LTS (3.13.0- 76-generic) .
But because the bug has fixed in upstream kernel since 4.2, the problem is not caused on 15.10 (4.2.0-30-generic).
I have not try to reproduce on 12.04 LTS yet, but if the kernel version is earlier than 4.2, the problem will be reproduced probably.