On 6/27/22, Peter Maydell <peter.mayd...@linaro.org> wrote: > On Mon, 27 Jun 2022 at 17:07, Jason A. Donenfeld <ja...@zx2c4.com> wrote: >> >> In 60592cfed2 ("hw/arm/virt: dt: add kaslr-seed property"), the >> kaslr-seed property was added, but the equally as important rng-seed >> property was forgotten about, which has identical semantics for a >> similar purpose. This commit implements it in exactly the same way as >> kaslr-seed. > > Not an objection, since if this is what the dtb spec says we need > to provide then I guess we need to provide it, but: > Why do we need to give the kernel two separate random seeds? > Isn't one sufficient for the kernel to seed its RNG and generate > whatever randomness it needs for whatever purposes it wants it? >
Seems a bit silly to me too. `rng-seed` alone ought to be sufficient. After the kernel calls add_bootloader_randomness() on it, get_random_long() can be used for kaslr'ing and everything else too. So I'm not sure what's up, but here we are. Maybe down the line I'll look into the details and formulate a plan to remove `kaslr-seed` if my supposition is correct. Jason