On 1 September 2015 at 14:52, Andre Przywara <andre.przywara@xxxxxxx> wrote: > Also the GIC specification says that everything must be accessible with > 32-bit accesses. Correct me if I am wrong on this, but vCPUs are not > supposed to run while you are getting/setting VGIC registers, right? So > there shouldn't be any issues with non-atomic accesses to 64-bit > registers, which means you could just go ahead and do everything in > 32-bit only. This would also help with supporting 32-bit userland and/or > kernel later. We should design the userspace API based on the natural size of the registers in the GICv3 spec, not on what happens to be convenient for the kernel to implement. There's only one kernel but there can be multiple userspace consumers of the API... I don't see any reason why a 32-bit userland wouldn't be able to handle 64-bit accesses via the KVM_SET/GET_DEVICE_ATTR ioctls, or am I missing something? thanks -- PMM -- 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
