On 24/09/2015 18:12, Bandan Das wrote: > Not sure myself what's the right thing to do but this may be undesirable > in a nested environment. Assuming the processor supports global invalidation > only, this seems like a easy way for the nested guest to invalidate *all* > mappings - even the L1 specific mappings. It's not a great thing but it's already what happens if you do a global INVEPT (it calls vmx_flush_tlb, which results in a global INVVPID if the single-context variant is not supported). Even without nested virt a single guest could slow down all other guests just by triggering frequent TLB flushes (e.g. by moving around a ROM BAR thousands of times per second). It would help to know _which_ processors actually don't support single-context INVVPIDs... Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
