Re: [PATCH RFC 2/4] x86/arch_prctl: add ARCH_GET_NOPTI and ARCH_SET_NOPTI to enable/disable PTI

[Peter Zijlstra]

On Mon, Jan 08, 2018 at 06:05:31PM +0100, Ingo Molnar wrote:
> Note that there is somewhat of a fuzzy detail regarding AMD CPUs which are marked 
> as 'Meltdown safe': should an explicit request to turn on PTI be honored by the 
> kernel? Should that be some sort of separate 'force PTI on' attribute?

AMD should not have FEATURE_PTI enabled, and thus not end up in any code
that cares about TIF_NOPTI.