Jeremy Fitzhardinge wrote: > Nakajima, Jun wrote: > > The hypervisor detection machanism is generic, and the signature > > returned is implentation specific. Having a list of all hypervisor > > signatures sounds fine to me as we are detecting vendor-specific > > processor(s) in the native. And I don't expect the list is large. > > > > > > I'm confused about what you're proposing. I was thinking that a kernel > looking for the generic hypervisor interface would check for a specific > signature at some cpuid leaf, and then go about using it from there. If > not, how does is it supposed to detect the generic hypervisor interface? > > J
I'm suggesting that we use CPUID.0x4000000Y (Y: TBD, e.g. 6) for Linux paravirtualization. The ebx, ecx and edx return the Linux paravirtualization features available on that hypervisor. Those features are defined architecturally (not VMM specific). Like CPUID.0, CPUID.0x40000000 is used to detect the hypervisor with the vendor identification string returned in ebx, edx, and ecx (as we are doing in Xen). The eax returns the max leaf (which is 0x40000002 on Xen today). And like CPUID.1, CPUID.0x40000001 returns the version number in eax, and each VMM should be able to define a number of VMM-specific features available in ebx, ecx, and edx returned (which are reserved, i.e. not used in Xen today). Suppose we knew (i.e. tested) Xen and KVM supported Linux paravirtualization, the Linux code does: 1. detect Xen or KVM <the list> using CPUID.0x40000000 2. Check the version if necessary using CPUID.0x40000001 3. Check the Linux paravirtualization features available using CPUID.0x4000000Y. Jun --- Intel Open Source Technology Center - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
