And we'll also have to make getrandom(0) be really _timely_. Security
people would likely rather wait for minutes before they are happy with
it. But because it's a boot constraint as things are now, it will not
just be jitter-entropy, it will be _accelerated_ jitter-entropy in 15
seconds or whatever, and since it can't use up all of CPU time, it's
realistically more like "15 second timeout, but less of actual CPU
time for jitter".
That said, if we can all convince everybody (hah!) that jitter entropy
in the kernel would be sufficient, then we can make the whole point
entirely moot, and just say "we'll just change crng_wait() to do
jitter entropy instead and be done with it. Then any getrandom() user
will just basically wait for a (very limited) time and the system will
be happy.
If that is the case we wouldn't need new flags at all. But I don't
think you can make everybody agree to that, which is why I suspect
we'll need the new flag, and I'll just take the heat for saying "0 is
now off limits, because it does this thing that a lot of people
dislike".
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