не могу закрыть luks

cryptsetup luksFormat -c aes-xts-plain64 -s 256 -h sha256 /dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi2 
cryptsetup luksOpen /dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi2 luks1
zpool create lpool /dev/mapper/luks1
touch /lpool/test
cryptsetup luksClose luks1
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
device-mapper: remove ioctl on luks1  failed: Device or resource busy
Device luks1 is still in use.