Hm? I don’t think this is true. It’s CS 0x23 and 0x33 just like on Windows, no? This is, afaik, how Wine WoW64 works. I cannot find a definitive source, but for ex: https://stackoverflow.com/questions/24113729/switch-from-32b...

I also think on Linux the x86 syscalls using software interrupts will still work in a 64 bit process, too.