我无法在 Ubuntu 18.04 LTS 上安装 Parallels Tools。这是错误日志：
Started installation of Parallels Guest Tools version '13.3.0.43321'
Thu Apr 26 21:45:11 PDT 2018
Start installation or upgrade of Guest Tools
new version of parallels tools
Installed Guest Tools were not found
Perform installation into the /usr/lib/parallels-tools directory
cat: /usr/lib/parallels-tools/kmods/../version: No such file or directory
make: Entering directory '/usr/lib/parallels-tools/kmods'
cd prl_eth/pvmnet && make
make[1]: Entering directory '/usr/lib/parallels-tools/kmods/prl_eth/pvmnet'
make -C /lib/modules/4.15.0-20-generic/build M=/usr/lib/parallels-tools/kmods/prl_eth/pvmnet
make[2]: Entering directory '/usr/src/linux-headers-4.15.0-20-generic'
Makefile:976: "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel"
CC [M] /usr/lib/parallels-tools/kmods/prl_eth/pvmnet/pvmnet.o
LD [M] /usr/lib/parallels-tools/kmods/prl_eth/pvmnet/prl_eth.o
Building modules, stage 2.
MODPOST 1 modules
FATAL: modpost: GPL-incompatible module prl_eth.ko uses GPL-only symbol 'sev_enable_key'
scripts/Makefile.modpost:92: recipe for target '__modpost' failed
make[3]: *** [__modpost] Error 1
Makefile:1555: recipe for target 'modules' failed
make[2]: *** [modules] Error 2
make[2]: Leaving directory '/usr/src/linux-headers-4.15.0-20-generic'
/usr/lib/parallels-tools/kmods/prl_eth/pvmnet/Makefile.v26:11: recipe for target 'all' failed
make[1]: *** [all] Error 2
make[1]: Leaving directory '/usr/lib/parallels-tools/kmods/prl_eth/pvmnet'
Makefile.kmods:34: recipe for target 'installme' failed
make: *** [installme] Error 2
make: Leaving directory '/usr/lib/parallels-tools/kmods'
Error: could not build kernel modules
Error: failed to install kernel modules
Error: failed to install Parallels Guest Tools!
Please, look at /var/log/parallels-tools-install.log file for more information.
但是，在 Ubuntu 16.04 LTS 上安装 Parallels Tools 时，一切正常。