lkml.org 
[lkml]   [2008]   [Oct]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [RFC] CPUID usage for interaction between Hypervisors and Linux.
    Jeremy Fitzhardinge wrote:
    > Alok Kataria wrote:
    >
    > No, we're not getting anywhere. This is an outright broken idea. The
    > space is too small to be able to chop up in this way, and the number of
    > vendors too large to be able to do it without having a central oversight.
    >
    > The only way this can work is by having explicit positive identification
    > of each group of leaves with a signature. If there's a recognizable
    > signature, then you can inspect the rest of the group; if not, then you
    > can't. That way, you can avoid any leaf usage which doesn't conform to
    > this model, and you can also simultaneously support multiple hypervisor
    > ABIs. It also accommodates existing hypervisor use of this leaf space,
    > even if they currently use a fixed location within it.
    >
    > A concrete counter-proposal:

    Mmm, cpuid bikeshedding :-)

    > The space 0x40000000-0x400000ff is reserved for hypervisor usage.
    >
    > This region is divided into 16 16-leaf blocks. Each block has the
    > structure:
    >
    > 0x400000x0:
    > eax: max used leaf within the leaf block (max 0x400000xf)

    Why even bother with this? It doesn't seem necessary in your proposal.

    Regards,

    Anthony Liguori


    \
     
     \ /
      Last update: 2008-10-01 22:07    [W:0.021 / U:151.412 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site