> I think I've read locks/hangs' reports even with newer APUs, and at this moment I'm not sure if disabling C6 state on package (or was it core?) is an effective workaround.

For me it is. It's triggered by the firmware setting:

    Advanced > AMD CBS > Zen Common Options > Power Supply Idle Control = "Common current idle" (instead of auto)

That disables package C6 state for me (checked with zenstates.py), and freezes and random reboots disappear after that:

    C6 State - Package - Disabled
    C6 State - Core - Enabled

On auto setting for the above, I get:

    C6 State - Package - Enabled
    C6 State - Core - Enabled

And it highly annoyingly randomly freezes and reboots in such case.

Another workaround is in the linked thread, to compile the kernel with special rcu options, I tried that, and it works, but it's not really a good method.

> don't know if they were joking when they said that Windows is never that idle...

I don't think they are joking.