Avoid speculative indirect branches in kernel

configname: CONFIG_RETPOLINE

Linux Kernel Configuration
└─>Mitigations for speculative execution vulnerabilities
└─>Avoid speculative indirect branches in kernel
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Compile kernel with the retpoline compiler options to guard against
kernel-to-user data leaks by avoiding speculative indirect
branches. Requires a compiler with -mindirect-branch=thunk-extern
support for full protection. The kernel may run slower.