Why not make /dev/urandom block, but only at boot time until sufficient entropy has been achieved? Then you could "trust" it, even in boot conditions and in nor

Why not make /dev/urandom block, but only at boot time until sufficient entropy has been achieved? Then you could "trust" it, even in boot conditions and in normal operations it would still never block… Or if the change in semantics is too onerous, a new /dev/drandom (delayed-random) could do this.