Comment 3 for bug 1584456

I worked with Yann on this issue today and can answer some of your questions:

1) there are no snaps installed other than

  - ubuntu-core
  - kernel (a modified raspberry-pi-kernel snap where modules/image/uboot.env has been changed)
  - hello-world

2)
There is no difference in the output of 'ls -lR /dev/ptmx /dev/pts' between before and after running hello-world.echo.

5) Tegra X1 Kernel version is 3.10.96+ (NVidia Tegra X1 + Parrot's drivers)

Running

  sudo mount -o bind,rw /dev/pts/ptmx /dev/ptmx

works.

The problem seems to be in the kernel part of apparmor adding the trailing slashes on this bind mount paths. Are there any custom patches applied to stock kernels before the can work with ubuntu-core?