What:		/sys/kernel/btf
Date:		Aug 2019
KernelVersion:	5.5
Contact:	bpf@vger.kernel.org
Description:
		Contains BTF type information and related data for kernel and
		kernel modules.

What:		/sys/kernel/btf/vmlinux
Date:		Aug 2019
KernelVersion:	5.5
Contact:	bpf@vger.kernel.org
Description:
		Read-only binary attribute exposing kernel's own BTF type
		information with description of all internal kernel types. See
		Documentation/bpf/btf.rst for detailed description of format
		itself.

What:		/sys/kernel/btf/<module-name>
Date:		Nov 2020
KernelVersion:	5.11
Contact:	bpf@vger.kernel.org
Description:
		Read-only binary attribute exposing kernel module's BTF type
		information as an add-on to the kernel's BTF (/sys/kernel/btf/vmlinux).