Re: [PATCH 04/23] x86, tlb: make CR4-based TLB flushes more robust

[Andy Lutomirski]

On Tue, Oct 31, 2017 at 3:31 PM, Dave Hansen
<dave.hansen@xxxxxxxxxxxxxxx> wrote:
>
> Our CR4-based TLB flush currently requries global pages to be
> supported *and* enabled.  But, we really only need for them to be
> supported.  Make the code more robust by alllowing X86_CR4_PGE to
> clear as well as set.
>
> This change was suggested by Kirill Shutemov.

I may have missed something, but why would be ever have CR4.PGE off?