I refreshed the snap from 5.2 to 5.3 today and I report a very similar issue for GUI enabled containers:
lxc development 20220630104100.475 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3592 - newuidmap binary is missing
lxc development 20220630104100.475 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3598 - newgidmap binary is missing
lxc development 20220630104100.475 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3592 - newuidmap binary is missing
lxc development 20220630104100.475 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3598 - newgidmap binary is missing
lxc development 20220630104100.475 WARN cgfsng - ../src/src/lxc/cgroups/cgfsng.c:fchowmodat:1252 - No such file or directory - Failed to fchownat(42, memory.oom.group, 1000000000, 0, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW )
lxc development 20220630104100.571 ERROR conf - ../src/src/lxc/conf.c:mount_entry:2459 - Operation not permitted - Failed to mount "/var/snap/lxd/common/lxd/devices/container_name/disk.Code.home-ubuntu-Code" on "/var/snap/lxd/common/lxc//home/ubuntu/some_folder"
lxc development 20220630104100.571 ERROR conf - ../src/src/lxc/conf.c:lxc_setup:4375 - Failed to setup mount entries
lxc development 20220630104100.571 ERROR start - ../src/src/lxc/start.c:do_start:1275 - Failed to setup container "container_name"
lxc development 20220630104100.571 ERROR sync - ../src/src/lxc/sync.c:sync_wait:34 - An error occurred in another process (expected sequence number 3)
lxc development 20220630104100.574 WARN network - ../src/src/lxc/network.c:lxc_delete_network_priv:3631 - Failed to rename interface with index 0 from "eth0" to its initial name "veth2f123d2b"
lxc development 20220630104100.574 ERROR lxccontainer - ../src/src/lxc/lxccontainer.c:wait_on_daemonized_start:877 - Received container state "ABORTING" instead of "RUNNING"
lxc development 20220630104100.574 ERROR start - ../src/src/lxc/start.c:__lxc_start:2074 - Failed to spawn container "container_name"
lxc development 20220630104100.574 WARN start - ../src/src/lxc/start.c:lxc_abort:1039 - No such process - Failed to send SIGKILL via pidfd 43 for process 33076
lxc development 20220630104105.689 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3592 - newuidmap binary is missing
lxc development 20220630104105.689 WARN conf - ../src/src/lxc/conf.c:lxc_map_ids:3598 - newgidmap binary is missing
lxc 20220630104105.730 ERROR af_unix - ../src/src/lxc/af_unix.c:lxc_abstract_unix_recv_fds_iov:218 - Connection reset by peer - Failed to receive response
lxc 20220630104105.730 ERROR commands - ../src/src/lxc/commands.c:lxc_cmd_rsp_recv_fds:127 - Failed to receive file descriptors for command "get_state"
Among the errors I see an issue in mapping a host folder and the network. However containers with mounted folders but no GUI work fine. So it will be something with the GUI … @simos could you please have a look?
I am at Ubuntu 20.04.4 with NVidia 470.129.06 driver.