Re: [RFC] /dev/ioasid uAPI proposal

Paolo Bonzini
2021-06-07T06:51:59Z

On 07/06/21 05:25, Tian, Kevin wrote:
> Per Intel SDM wbinvd is a privileged instruction. A process on the
> host has no privilege to execute it.

(Half of) the point of the kernel is to do privileged tasks on the
processes' behalf. There are good reasons why a process that uses VFIO
(without KVM) could want to use wbinvd, so VFIO lets them do it with a
ioctl and adequate checks around the operation.

Paolo