Re: [PATCH] random: remove CONFIG_ARCH_RANDOM and "nordrand"

H. Peter Anvin
2022-07-05T23:12:29Z

On July 5, 2022 3:00:04 PM PDT, Borislav Petkov <bp@alien8.de> wrote:
>On Tue, Jul 05, 2022 at 02:50:34PM -0700, H. Peter Anvin wrote:
>> It's just math. The only variable is your confidence level, i.e. at
>> what level do you decide that the likelihood of pure chance is way
>> smaller than the likelihood of hardware failure.
>
>That might be but the likelyhood of certain BIOSes dropping the ball
>after resume is 100%:
>
>7879fc4bdc75 ("x86/rdrand: Sanity-check RDRAND output")
>

What I'm wondering is if we shouldn't be simply instrument *every* invocation, and set the trust to zero if we ever trip it.