On Wed, May 27, 2009 at 9:28 AM, Avi Kivity <avi@xxxxxxxxxx> wrote: > Will it actually solve the problem? > > - can all hypercalls that can be issued with > pv-on-hvm-on-kvm-with-a-side-order-of-fries be satisfied from userspace? > - what about connecting the guest driver to xen netback one day? we don't > want to go through userspace for that. In Gerd's current implementation, the code in the hypercall page (which the guest maps in using that pesky MSR) handles all hypercalls either internally or by invoking userspace (via another magic IO port). I'm too ignorant of Xen to claim that my proposal solves the problem completely, but after hacking in support for delegating the magic MSR to userspace, I got an unmodified FreeBSD disk image to boot in PV-on-HVM-on-KVM+Qemu and use Xen PV network devices. > We can consider catering to Xen and implementing that MSR in the kernel, if > it's truly one off. One way or another, the MSR somehow has to map in a chunk of data supplied by userspace. Are you suggesting an alternative to the PIO hack? --Ed -- 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
