
AMD Releases BIOS Fix for Booting Newer Linux Distributions - jjuhl
https://www.phoronix.com/scan.php?page=news_item&px=AMD-Releases-Linux-Zen2-Fix
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johnklos
This really should be fixed in systemd.

First, randomness should be done in the kernel, not in systemd.

Second, we should have a choice about whether to use hardware-based randomness
or not.

Third, any failure to boot due to randomness is just inherently broken. I
would LOVE to have someone explain to me how any system that even has the
possibility of not booting because of a random number generator is in any way
correct or desirable.

~~~
jameshilliard
Well systemd did add a workaround but it's pretty hard to fault them here
since their original implementation followed the RDRAND spec:

[https://github.com/systemd/systemd/pull/12536/commits/1c53d4...](https://github.com/systemd/systemd/pull/12536/commits/1c53d4a070edbec8ad2d384ba0014d0eb6bae077)

Systemd does not have its own random number generator:

[https://github.com/systemd/systemd/issues/11810#issuecomment...](https://github.com/systemd/systemd/issues/11810#issuecomment-509418688)

    
    
      > No, let's not roll our own PRNGs, we don't want to maintain that. it's fine to use the CPU RNG, the kernels or glibc's, but I don't want to maintain our own version in our codebase, sorry.
    

There are good reasons for using RDRAND for UUID generation since it's
required very early during boot often before the kernel's random pool is
filled. This sort of issue is especially common on embedded systems, I've had
to use haveged to fill the kernel entropy pool otherwise many applications
don't startup properly.:

[https://unix.stackexchange.com/questions/442698/when-i-
log-i...](https://unix.stackexchange.com/questions/442698/when-i-log-in-it-
hangs-until-crng-init-done)

~~~
nwmcsween
So they can't use AT_RANDOM to either seed a prng or just use it directly?

