[cpeterso]

Linux's /dev/urandom does not trust hardware RNGs any more than other entropy sources. All entropy sources are stirred into the same entropy pool.

[ballard]

Does it use multiple pools a-la Fortuna?

[__alexs]

There's an input pool and 2 output pools but it's not like Fortuna. This is the most up to date analysis of the Linux entropy system I'm aware of http://eprint.iacr.org/2012/251.pdf