Re: [RFC PATCH] x86: Filter MSR writes from luserspace

[Andi Kleen]

On Tue, Nov 26, 2019 at 09:33:36PM +0100, Borislav Petkov wrote:
> On Tue, Nov 26, 2019 at 12:15:10PM -0800, Andi Kleen wrote:
> > This will break a bazillion of tools that rely on programing many of
> > those MSRs from user space.
> 
> Userspace has no deal to poke into random MSRs. End of story.

You'll almost certainly violate Linus' golden rule of application
compatibility and the whole thing will be reverted in the end.

-Andi