While I'm sure there are folks that would appreciate the mitigation provided by that package, I'm not sure it provides any mitigation to this _specific_ exploit

While I'm sure there are folks that would appreciate the mitigation provided by that package, I'm not sure it provides any mitigation to this _specific_ exploit. The in-kernel Spectre-v1 mitigations, like: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c7f631cb07e7da06ac1d231ca178452339e32a94 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin... are cheap and ubiquitous. You don't have to turn them on, and they're so cheap you can't even turn them off if you wanted. Disclaimer: I work on Linux at Intel.