Never mind. Fixed it. Copied /etc to tmp, removed /etc, copied it back. Don't yet know why this fixed things.
2.6.16-1.2080_FC5
references to /etc/mtab by any utilities which concern mounting, including usb, removable media, internal disks, "df", etc. fail with "/etc/mtab input/output error".
proc/mounts is visible and populated.
This makes it impossible to mount usb, accumulates tons of error messages in dmesg and /var/log/messages.
First appeared after FC5 updates with:
Apr 8 06:58:32 localhost kernel: audit(1144504677.102:2): avc: denied { getattr } for pid=1292 comm="mount" name="mtab" dev=sda6 ino=8799416 scontext=system_u:system_r:mount_t:s0 tcontext=system_u
bject_r:unlabeled_t:s0 tclass=file
Turned off selinux, no change.
also noticed when restarting nfs:
Starting RPC idmapd: Error: RPC MTAB does not exist.
and
[root@dtxps1 etc]# ln -s /proc/mount /etc/mtab
ln: accessing `/etc/mtab': Input/output error
[root@dtxps1 etc]# ls /etc/mtab
ls: /etc/mtab: Input/output error
Thank you.
Charlie Collins