[zx2c4]

> I think you can still have specific reservations about CPU execution time jitter, though my experience [...]

Just want to point out that the Linus Jitter Dance is already in use today. It's been there for three years. I had nothing to do with that change. The change that I'm now proposing, which this article is about, changes nothing about the Linus Jitter Dance. Whether you like it or not, it's being used already, and has been for three years now, affecting all interfaces to the rng.

I only mention it in my patch, for the sole purpose of indicating that blocking in /dev/urandom has been unproblematic for three years now, because it will unblock a second later. That's the only at all reason why I mention the Linus Jitter Dance.

The only purpose of the patch is to make /dev/urandom block.

> I also think you can still have specific reservations about how the kernel 'shepherds' its pool of random bits. [...] It would seem best if the kernel used a cryptographic algorithm

Actually, it will do this for 5.18, authored a few weeks ago: https://git.kernel.org/pub/scm/linux/kernel/git/crng/random....