Different ways of doing a system call

[Aleksander Alekseev]

Hello

Recently I've explored different ways of doing a system call on Linux
(only on x86 and x64 architectures). Here is what I discovered so far:

* int 0x80        (x86, slow)
* sysenter        (x86, fast)
* vsyscall        (x86, deprecated)
* VDSO trampoline (x86, fast)
* syscall         (x64, fast)

Tell me, please:

* Didn't I miss anything?
* What are _recommended_ ways of doing a system call on x86 and x64?
* I just wanted to clarify - in theory it's OK to use both say int 0x80
  and syscall in the same ELF64 binary? Wouldn't it cause a program to
  crash or something?

-- 
Best regards,
Aleksander Alekseev