On Mon, Jan 29, 2018 at 05:10:11PM -0500, Konrad Rzeszutek Wilk wrote: [...] > The migration code could be 'tickled' (when arrived at the destination) > to recheck the CPUID and do the alternative logic to turn the > proper bits on. > > And this tickling could be as simple as an ACPI DSDT/AML code > specific to KVM PnP devices (say the CPUs?) to tell the guest to > resample its environment? This would be nice to have for other CPU features, but if I understood a previous message from Andi on this thread correctly, it wouldn't be useful for the Spectre mitigations. -- Eduardo