Re: [PATCH v6 net-next 4/6] bpf: enable bpf syscall on x64 and i386

From: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
Date: Mon, 25 Aug 2014 18:00:56 -0700

-
+asmlinkage long sys_bpf(int cmd, unsigned long arg2, unsigned long arg3,
+			unsigned long arg4, unsigned long arg5);

Please do not add interfaces with opaque types as arguments.

It is impossible for the compiler to type check the args at
compile time when userspace tries to use this stuff.