/usr/include/xenomai/asm-generic/ is in libxenomai-dev 2.6.3-2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/xenomai/asm-generic/arith.h
/usr/include/xenomai/asm-generic/bind.h
/usr/include/xenomai/asm-generic/bits/
/usr/include/xenomai/asm-generic/bits/heap.h
/usr/include/xenomai/asm-generic/bits/intr.h
/usr/include/xenomai/asm-generic/bits/pod.h
/usr/include/xenomai/asm-generic/bits/timeconv.h
/usr/include/xenomai/asm-generic/current.h
/usr/include/xenomai/asm-generic/features.h
/usr/include/xenomai/asm-generic/hal.h
/usr/include/xenomai/asm-generic/pci_ids.h
/usr/include/xenomai/asm-generic/sem_heap.h
/usr/include/xenomai/asm-generic/sigshadow.h
/usr/include/xenomai/asm-generic/stack.h
/usr/include/xenomai/asm-generic/syscall.h
/usr/include/xenomai/asm-generic/system.h
/usr/include/xenomai/asm-generic/timeconv.h
/usr/include/xenomai/asm-generic/wrappers.h
/usr/include/xenomai/asm-generic/xenomai