error output buildroot

>>>   Generating root filesystem image rootfs.iso9660
/usr/bin/install -D -m 0644 fs/iso9660/grub.cfg /home/viro/Buildroot/output/build/rootfs.iso9660.tmp/boot/grub/grub.cfg
/bin/sed -i -e "s%__KERNEL_PATH__%/boot/bzImage%" /home/viro/Buildroot/output/build/rootfs.iso9660.tmp/boot/grub/grub.cfg
/usr/bin/install -D -m 0644 /home/viro/Buildroot/output/images/grub-eltorito.img /home/viro/Buildroot/output/build/rootfs.iso9660.tmp/boot/grub/grub-eltorito.img
/usr/bin/install: cannot stat '/home/viro/Buildroot/output/images/grub-eltorito.img': No such file or directory
fs/iso9660/iso9660.mk:160: recipe for target '/home/viro/Buildroot/output/images/rootfs.iso9660' failed
make[1]: *** [/home/viro/Buildroot/output/images/rootfs.iso9660] Error 1
Makefile:79: recipe for target '_all' failed
make: *** [_all] Error 2