Function LoadKernelSpec

btf/kernel.go:26–70

LoadKernelSpec returns the current kernel's BTF information. Defaults to /sys/kernel/btf/vmlinux and falls back to scanning the file system for vmlinux ELFs. Returns an error wrapping [ErrNotSupported] if BTF is not enabled. Consider using [Cache] instead.

()

//
// Consider using [Cache] instead.
func LoadKernelSpec() (*Spec, error) {
	if platform.IsWindows {
		return nil, internal.ErrNotSupportedOnOS
	}

	fh, err := os.Open("/sys/kernel/btf/vmlinux")
	if err == nil {
		defer fh.Close()

		info, err := fh.Stat()
		if err != nil {
			return nil, fmt.Errorf("stat vmlinux: %w", err)
		}

		// NB: It's not safe to mmap arbitrary files because mmap(2) doesn't
		// guarantee that changes made after mmap are not visible in the mapping.
		//
		// This is not a problem for vmlinux, since it is always a read-only file.
		raw, err := unix.Mmap(int(fh.Fd()), 0, int(info.Size()), unix.PROT_READ, unix.MAP_PRIVATE)
		if err != nil {
			return LoadSplitSpecFromReader(fh, nil)
		}

		spec, err := loadRawSpec(raw, nil)
		if err != nil {
			_ = unix.Munmap(raw)
			return nil, fmt.Errorf("load vmlinux: %w", err)
		}

		runtime.AddCleanup(spec.decoder.sharedBuf, func(b []byte) {
			_ = unix.Munmap(b)
		}, raw)

		return spec, nil
	}

	file, err := findVMLinux()
	if err != nil {
		return nil, err
	}
	defer file.Close()

	spec, err := LoadSpecFromReader(file)
	return spec, err
}

// LoadKernelModuleSpec returns the BTF information for the named kernel module.
//