Tiens, une information donnée clairement par findmnt et non par mount, les montages snap en boucle :
bionic@k72f-J48-ubgnome:~$ findmnt -o +SIZE,USED |grep -E "^TARGET| /dev/"
TARGET SOURCE FSTYPE OPTIONS SIZE USED
/ /dev/sda3[/@-bionic] btrfs rw,relatime,space_cache,subvolid=257,subvol=/@-bionic 53,3G 20,4G
├─/home /dev/sda3[/@-bionic-home] btrfs rw,relatime,space_cache,subvolid=258,subvol=/@-bionic-home 53,3G 20,4G
├─/snap/core/6405 /dev/loop0 squashfs ro,nodev,relatime 91M 91M
├─/snap/hello-world/27 /dev/loop1 squashfs ro,nodev,relatime 128K 128K
└─/snap/vlc/770 /dev/loop2 squashfs ro,nodev,relatime 202,4M 202,4M
bionic@k72f-J48-ubgnome:~$
à comparer avec :
bionic@k72f-J48-ubgnome:~$ mount -l
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=1887128k,nr_inodes=471782,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=383508k,mode=755)
/dev/sda3 on / type btrfs (rw,relatime,space_cache,subvolid=257,subvol=/@-bionic) [Tests]
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755)
cgroup on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
efivarfs on /sys/firmware/efi/efivars type efivarfs (rw,nosuid,nodev,noexec,relatime)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=29,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=1724)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
mqueue on /dev/mqueue type mqueue (rw,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)
configfs on /sys/kernel/config type configfs (rw,relatime)
/dev/sda3 on /home type btrfs (rw,relatime,space_cache,subvolid=258,subvol=/@-bionic-home) [Tests]
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
tmpfs on /run/user/108 type tmpfs (rw,nosuid,nodev,relatime,size=383504k,mode=700,uid=108,gid=114)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=383504k,mode=700,uid=1000,gid=1000)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
/var/lib/snapd/snaps/core_6405.snap on /snap/core/6405 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/hello-world_27.snap on /snap/hello-world/27 type squashfs (ro,nodev,relatime,x-gdu.hide)
tmpfs on /run/snapd/ns type tmpfs (rw,nosuid,noexec,relatime,size=383508k,mode=755)
nsfs on /run/snapd/ns/hello-world.mnt type nsfs (rw)
/var/lib/snapd/snaps/vlc_770.snap on /snap/vlc/770 type squashfs (ro,nodev,relatime,x-gdu.hide)
bionic@k72f-J48-ubgnome:~
Les montages snap sont visibles mais cela ne saute pas aux yeux, par contre les fichiers montés en boucle sont identifiables contrairement avec findmnt qui doit être complété de la commande losetup pour cette identification:
[code]bionic@k72f-J48-ubgnome:~$ losetup -l
NAME SIZELIMIT OFFSET AUTOCLEAR RO BACK-FILE DIO LOG-SEC
/dev/loop1 0 0 1 1 /var/lib/snapd/snaps/hello-world_27.snap 0 512
/dev/loop2 0 0 1 1 /var/lib/snapd/snaps/vlc_770.snap 0 512
/dev/loop0 0 0 1 1 /var/lib/snapd/snaps/core_6405.snap 0 512
bionic@k72f-J48-ubgnome:~$
[/code]