On Wed, 12 Feb 2014 11:20:00 -0700, Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Feb 12, 2014 at 12:45:54PM -0500, Jason Cooper wrote: > > > The bootloader would then load this file into ram, and pass the > > address/size to the kernel either via dt, or commandline. kaslr (run in > > the decompressor) would consume some of this randomness, and then > > random.c would consume the rest in a non-crediting initialization. > > Sure is a neat idea, but I think in general it would probably be smart > to include the entire FDT blob in the early random pool, that way you > get MACs and other machine unique data too. I applied a patch that did exactly that (109b623629), and then reverted it (b920ecc82) shortly thereafter because add_device_randomness() is a rather slow function and FDTs can get large. I'd like to see someone do a reasonable analysis on the cost of using an FDT for randomness before I reapply a patch doing something similar. An awful lot of the FDT data is not very random, but there are certainly portions of it that are appropriate for the random pool. g. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
