Cannot make

[lutfiirhmn]

make[1]: Entering directory '/usr/src/linux-headers-5.13.0-1019-gcp'
CC [M] /root/hiding-cryptominers-linux-rootkit/main.o
LD [M] /root/hiding-cryptominers-linux-rootkit/rootkit.o
MODPOST /root/hiding-cryptominers-linux-rootkit/Module.symvers
CC [M] /root/hiding-cryptominers-linux-rootkit/rootkit.mod.o
LD [M] /root/hiding-cryptominers-linux-rootkit/rootkit.ko
BTF [M] /root/hiding-cryptominers-linux-rootkit/rootkit.ko
Skipping BTF generation for /root/hiding-cryptominers-linux-rootkit/rootkit.ko due to unavailability of vmlinux
make[1]: Leaving directory '/usr/src/linux-headers-5.13.0-1019-gcp'