Here's what "mount" says in a uClinux appliance:
rootfs on / type rootfs (rw)
/dev/root on / type yaffs (rw)
proc on /proc type proc (rw)
ramfs on /var/tmp type ramfs (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw)
usbfs on /proc/bus/usb type usbfs (rw)
securityfs on /sys/kernel/security type securityfs (rw)
Does someone know why "/" is mounted twice?
And I'd like to double-check that the other entries, which don't contain a physical device as source are indeed just kernel data structures.