The clearcpuid= kernel parameter can be used to disable specific CPUID features for the kernel by specifying the targeted bit numbers of the feature(s) to disable or their flags from the /proc/cpuinfo output. The clearcpuid parameter, for example, has been useful for carrying out AVX-512 comparison benchmarks for apps that check for the presence of the AVX-512 extensions via /proc/cpuinfo. But moving forward the documentation on clearcpuid is being removed to discourage its use...