On Thu, Oct 03, 2013 at 11:06:58PM +0000, Dilger, Andreas wrote: > > The Lustre cfs_get_random_bytes() incorporates (via cfs_rand()) a seed > which > also hashes in the addresses from any network interfaces that are > configured. > Conversely, cfs_rand() also is seeded at startup from get_random_bytes() in > case a hardware RNG is available. This ensures even with identical initial > conditions cfs_get_random_bytes() gets a different random stream on each > node. With modern kernels, the /dev/random driver has the add_device_randomness() interface which is used to mix in personalization information, which includes the network MAC address. So that particular concern should be covered without the hack of mixing in cfs_rand(). > I'm not against cleaning this up, if there is some mechanism for the > startup code to add in the node interface addresses into the entropy > pool, and this is also used to perturb the prandom_u32() sequence > after that point. That's handled too, via the late initcall prandom_reseed(). Cheers, - Ted _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
