# Pastebin TTN36845
google:fedora-29-64 /root# /usr/libexec/snapd/snap-discard-ns test-snapd-udev-input-subsystem
google:fedora-29-64 /root# SNAPD_DEBUG=1 test-snapd-udev-input-subsystem.slot
2018/11/08 14:42:52.114300 cmd_linux.go:70: DEBUG: re-exec not supported on distro "fedora" yet
DEBUG: security tag: snap.test-snapd-udev-input-subsystem.slot
DEBUG: executable:   /usr/lib/snapd/snap-exec
DEBUG: confinement:  non-classic
DEBUG: base snap:    core
DEBUG: ruid: 0, euid: 0, suid: 0
DEBUG: rgid: 0, egid: 0, sgid: 0
DEBUG: creating lock directory /run/snapd/lock (if missing)
DEBUG: opening lock directory /run/snapd/lock
DEBUG: opening lock file: /run/snapd/lock/.lock
DEBUG: sanity timeout initialized and set for three seconds
DEBUG: acquiring exclusive lock (scope (global), uid 0)
DEBUG: sanity timeout reset and disabled
DEBUG: ensuring that snap mount directory is shared
DEBUG: unsharing snap namespace directory
DEBUG: releasing lock 4
DEBUG: snap-update-ns executable: /usr/libexec/snapd/snap-update-ns
DEBUG: opened snap-update-ns executable as file descriptor 3
DEBUG: creating lock directory /run/snapd/lock (if missing)
DEBUG: opening lock directory /run/snapd/lock
DEBUG: opening lock file: /run/snapd/lock/test-snapd-udev-input-subsystem.lock
DEBUG: sanity timeout initialized and set for three seconds
DEBUG: acquiring exclusive lock (scope test-snapd-udev-input-subsystem, uid 0)
DEBUG: sanity timeout reset and disabled
DEBUG: initializing mount namespace: test-snapd-udev-input-subsystem
DEBUG: forked support process 24178
DEBUG: created new mount namespace
DEBUG: unsharing the mount namespace
DEBUG: scratch directory for constructing namespace: /tmp/snap.rootfs_LZfAfD
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: pivot_root /tmp/snap.rootfs_LZfAfD /tmp/snap.rootfs_LZfAfD//var/lib/snapd/hostfs
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: rmdir /var/lib/snapd/hostfs//tmp/snap.rootfs_LZfAfD
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: performing operation: (disabled) use debug build to see details
DEBUG: DEBUG: performing operation: (disabled) use debug build to see detailshelper process waiting for command
DEBUG: 
DEBUG: sanity timeout initialized and set for three seconds
performing operation: (disabled) use debug build to see details
DEBUG: performing operation: mount --move /var/lib/snapd /tmp/snapd.quirks_6bM6al
DEBUG: creating writable mimic directory /var/lib based on /snap/core/current//var/lib
DEBUG: mounting tmpfs at /var/lib
DEBUG: bind-mounting all the files from the reference directory
DEBUG: creating empty directory at /var/lib/apparmor
DEBUG: performing operation: mount /snap/core/current//var/lib/apparmor /var/lib/apparmor -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/classic
DEBUG: performing operation: mount /snap/core/current//var/lib/classic /var/lib/classic -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/cloud
DEBUG: performing operation: mount /snap/core/current//var/lib/cloud /var/lib/cloud -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/console-conf
DEBUG: performing operation: mount /snap/core/current//var/lib/console-conf /var/lib/console-conf -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/dbus
DEBUG: performing operation: mount /snap/core/current//var/lib/dbus /var/lib/dbus -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/dhcp
DEBUG: performing operation: mount /snap/core/current//var/lib/dhcp /var/lib/dhcp -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/extrausers
DEBUG: performing operation: mount /snap/core/current//var/lib/extrausers /var/lib/extrausers -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/initramfs-tools
DEBUG: performing operation: mount /snap/core/current//var/lib/initramfs-tools /var/lib/initramfs-tools -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/initscripts
DEBUG: performing operation: mount /snap/core/current//var/lib/initscripts /var/lib/initscripts -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/insserv
DEBUG: performing operation: mount /snap/core/current//var/lib/insserv /var/lib/insserv -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/logrotate
DEBUG: performing operation: mount /snap/core/current//var/lib/logrotate /var/lib/logrotate -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/machines
DEBUG: performing operation: mount /snap/core/current//var/lib/machines /var/lib/machines -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/misc
DEBUG: performing operation: mount /snap/core/current//var/lib/misc /var/lib/misc -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/pam
DEBUG: performing operation: mount /snap/core/current//var/lib/pam /var/lib/pam -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/python
DEBUG: performing operation: mount /snap/core/current//var/lib/python /var/lib/python -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/resolvconf
DEBUG: performing operation: mount /snap/core/current//var/lib/resolvconf /var/lib/resolvconf -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/snapd
DEBUG: performing operation: mount /snap/core/current//var/lib/snapd /var/lib/snapd -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/sudo
DEBUG: performing operation: mount /snap/core/current//var/lib/sudo /var/lib/sudo -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/systemd
DEBUG: performing operation: mount /snap/core/current//var/lib/systemd /var/lib/systemd -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/ubuntu-fan
DEBUG: performing operation: mount /snap/core/current//var/lib/ubuntu-fan /var/lib/ubuntu-fan -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/ucf
DEBUG: performing operation: mount /snap/core/current//var/lib/ucf /var/lib/ucf -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/update-rc.d
DEBUG: performing operation: mount /snap/core/current//var/lib/update-rc.d /var/lib/update-rc.d -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/urandom
DEBUG: performing operation: mount /snap/core/current//var/lib/urandom /var/lib/urandom -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/vim
DEBUG: performing operation: mount /snap/core/current//var/lib/vim /var/lib/vim -o ro,nosuid,nodev,rbind,rslave
DEBUG: creating empty directory at /var/lib/waagent
DEBUG: performing operation: mount /snap/core/current//var/lib/waagent /var/lib/waagent -o ro,nosuid,nodev,rbind,rslave
DEBUG: performing operation: umount /var/lib/snapd
DEBUG: performing operation: mount --move /tmp/snapd.quirks_6bM6al /var/lib/snapd
DEBUG: performing operation: rmdir /tmp/snapd.quirks_6bM6al
DEBUG: calling snap-update-ns to initialize mount namespace
DEBUG: waiting for snap-update-ns to finish...
DEBUG: launching snap-update-ns under per-snap profile snap-update-ns.test-snapd-udev-input-subsystem
DEBUG: fexecv(3 (snap-update-ns), snap-update-ns --from-snap-confine test-snapd-udev-input-subsystem,)
main.go:104: DEBUG: locking mount namespace of snap "test-snapd-udev-input-subsystem"
main.go:123: DEBUG: freezing processes of snap "test-snapd-udev-input-subsystem"
main.go:251: DEBUG: desired mount profile: (none)
main.go:251: DEBUG: current mount profile (before applying changes): (none)
change.go:469: DEBUG: desiredIDs: map[]
change.go:470: DEBUG: reuse: map[]
main.go:262: DEBUG: mount changes needed: (none)
main.go:204: DEBUG: performing mount changes:
main.go:251: DEBUG: current mount profile (after applying changes): (none)
main.go:190: DEBUG: saving current mount profile of snap "test-snapd-udev-input-subsystem"
main.go:128: DEBUG: thawing processes of snap "test-snapd-udev-input-subsystem"
main.go:100: DEBUG: unlocking mount namespace of snap "test-snapd-udev-input-subsystem"
DEBUG: snap-update-ns finished successfully
DEBUG: sending command 1 to helper process (pid: 24178)
DEBUG: DEBUG: sanity timeout reset and disabled
DEBUG: helper process received command 1
DEBUG: capturing per-snap mount namespace
waiting for response from helperDEBUG: 
mount namespace of process 24173 preserved as test-snapd-udev-input-subsystem.mnt
DEBUG: DEBUG: helper process waiting for command
DEBUG: sanity timeout initialized and set for three seconds
moved process 24173 to freezer cgroup hierarchy for snap test-snapd-udev-input-subsystem
DEBUG: releasing lock 5
DEBUG: sc_setup_user_mounts: test-snapd-udev-input-subsystem
DEBUG: sending command 0 to helper process (pid: 24178)
DEBUG: DEBUG: sanity timeout reset and disabled
DEBUG: helper process received command 0
DEBUG: helper process exiting
waiting for response from helper
DEBUG: waiting for the helper process to exit
DEBUG: helper process exited normally
DEBUG: resetting PATH to values in sync with core snap
DEBUG: snappy_udev_init
DEBUG: setup_devices_cgroup
DEBUG: write_string_to_file /sys/fs/cgroup/devices/snap.test-snapd-udev-input-subsystem.slot/tasks 24173
DEBUG: write_string_to_file /sys/fs/cgroup/devices/snap.test-snapd-udev-input-subsystem.slot/devices.deny a
DEBUG: run_snappy_app_dev_add: /sys/class/mem/null snap_test-snapd-udev-input-subsystem_slot
DEBUG: running snap-device-helper add snap_test-snapd-udev-input-subsystem_slot /sys/class/mem/null 1:3
execl failed: No such file or directory
child exited with status 1