Re: [RFC v2 01/32] x86/paravirt: Introduce CONFIG_PARAVIRT_XL

From: Peter Zijlstra
Date: Wed May 12 2021 - 09:19:18 EST


On Mon, May 10, 2021 at 05:56:05PM +0200, Juergen Gross wrote:

> No. We have PARAVIRT_XXL for Xen PV guests, and we have PARAVIRT for
> other hypervisor's guests, supporting basically the TLB flush operations
> and time related operations only. Adding the halt related operations to
> PARAVIRT wouldn't break anything.

Also, I don't think anything modern should actually ever hit any of the
HLT instructions, most everything should end up at an MWAIT.

Still, do we wants to give arch_safe_halt() and halt() the
PVOP_ALT_VCALL0() treatment?