I came across an article at Ars Technica https://arstechnica.com/gadgets/2019/02/google-software-is-never-going-to-be-able-to-fix-spectre-type-bugs/ detailing a paper by Google researchers mentioning that the Spectre vulnerability that affects all modern processors seem to have no software defenses in some cases.
From the article:
And whatever the cost, the researchers continue, the software will be inadequate—some Spectre flaws don’t appear to have any effective software-based defense.
I recommend checking out the article. Definitely a security related issue.