How can I make Linux reboot instead of remounting the filesystem as read-only?

Linux systems sometimes remount the root file system as read-only, e.g. if there's an I/O error.

I have a machine that becomes useless when this happens, and I end up rebooting it manually.

Is there a way to make Linux just automatically reboot when this happens? A read-only mount is useless to me.

I deduce you are using ext3 or ext4 as the file system. If so, you can mount it with the errors=panic option and configure watchdog to reboot your system in case a panic happen.

While more complex than roelvanmeer's answer (which I upvoted), it has the added bonus of working for all panic-level kernel crash.

As suggested by NikitaKipriyanov, setting the panic=5 kernel boot option can be a simpler alternative to watchdog (which has more configuration options but it is slightly more complex as result).

Maybe not a very pretty solution, but my first thought would be to run a command from cron every minute:

test -w / || reboot