On 15 April 2013 09:54, Christoffer Dall <cdall@xxxxxxxxxxxxxxx> wrote: > On Mon, Apr 15, 2013 at 1:43 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote: >> As for the affinity, we can enforce this very easily. >> > OK, but let's not go down this road until we've verified that this is > really an issue that needs to be handled by excluding A7s. Andre, can > you give us some more details? We *must* exclude KVM vcpu threads from ever running on A7s, because the cp15 handling code as it stands does not virtualize various registers (most notably the ID/feature registers) and so the vcpu will bounce between "looks like an A15" and "looks like a weird hybrid between A7 and A15". Assuming we don't want to tackle full big.LITTLE host support right now, I can see two options: * forbid KVM completely on a system with any non-A15s * force KVM vcpus to only ever run on the A15s [Q: does all the hyp mode code have to also run on the A15s or is it A7-safe?] -- PMM _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
