/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/ is in linux-kvm-headers-4.4.0-1031 4.4.0-1031.37.
This file is owned by root:root, with mode 0o755.
..
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/Kconfig
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/Makefile
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/Kconfig
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/Makefile
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/amd/
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/amd/Kconfig
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/amd/Makefile
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/intel/
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/intel/Kconfig
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/hw/intel/Makefile
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/test/
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/test/Kconfig
/usr/src/linux-kvm-headers-4.4.0-1031/drivers/ntb/test/Makefile