Re: [PATCH] hw/arm/virt: dt: add rng-seed property

[Peter Maydell]

On Tue, 28 Jun 2022 at 19:45, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> On 6/27/22, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> > On 6/27/22, Peter Maydell <peter.maydell@linaro.org> wrote:
> >> On Mon, 27 Jun 2022 at 17:07, Jason A. Donenfeld <Jason@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
> >
>
> Was wondering if you planned to queue this up?

It's on my todo list to review...

-- PMM