puppetlabs/facter — pull request #683 by ffrank (2014-05-25 21:51:43+00:00)
Title: (FACT-484) check dmi sysfs file for readability instead of just existence

Retrieving the virtual fact without root privileges would yield
warning messages due to missing permissions on
/sys/firmware/dmi/entries/1-0/raw (at least on certain versions of Debian).

The readable? query makes more sense than exists? at this point, anyway.