Zachary Amsden wrote: > On Fri, 2007-09-14 at 16:44 -0500, Anthony Liguori wrote: > > >> So then each module creates a hypercall page using this magic MSR and >> the hypervisor has to keep track of it so that it can appropriately >> change the page on migration. The page can only contain a single >> instruction or else it cannot be easily changed (or you have to be able >> to prevent the guest from being migrated while in the hypercall page). >> >> We're really talking about identical models. Instead of an MSR, the #GP >> is what tells the hypervisor to update the instruction. The nice thing >> about this is that you don't have to keep track of all the current >> hypercall page locations in the hypervisor. >> > > I agree, multiple hypercall pages is insane. I was thinking more of a > single hypercall page, fixed in place by the hypervisor, not the kernel. > > Then each module can read an MSR saying what VA the hypercall page is > at, and the hypervisor can simply flip one page to switch architectures. >
That requires a memory hole though. In KVM, we don't have a memory hole. Regards, Anthony Liguori > Zach > > ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
