Thank you for your reactions. Here are the outputs you requested:
TVBox:~ # ls -l /sys/block/
total 0
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop0 -> ../devices/virtual/block/loop0
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop1 -> ../devices/virtual/block/loop1
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop2 -> ../devices/virtual/block/loop2
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop3 -> ../devices/virtual/block/loop3
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop4 -> ../devices/virtual/block/loop4
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop5 -> ../devices/virtual/block/loop5
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop6 -> ../devices/virtual/block/loop6
lrwxrwxrwx 1 root root 0 Apr 3 06:26 loop7 -> ../devices/virtual/block/loop7
lrwxrwxrwx 1 root root 0 Sep 3 2019 sda -> ../devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1:1.0/host0/target0:0:0/0:0:0:0/block/sda
TVBox:~ # mount
devtmpfs on /dev type devtmpfs (rw,relatime,size=1958832k,nr_inodes=489708,mode=755)
proc on /proc type proc (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
/dev/sda1 on /flash type vfat (ro,noatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
/dev/loop0 on / type squashfs (ro,relatime)
/dev/sda2 on /storage type ext4 (rw,noatime,data=ordered)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,mode=755)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime)
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)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
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/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/debug type cgroup (rw,nosuid,nodev,noexec,relatime,debug)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
tmpfs on /var type tmpfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
And the dmesg:
http://ix.io/2grT