• Scott Wood's avatar
    KVM: PPC: Paravirtualize SPRG4-7, ESR, PIR, MASn · b5904972
    Scott Wood authored
    This allows additional registers to be accessed by the guest
    in PR-mode KVM without trapping.
    
    SPRG4-7 are readable from userspace.  On booke, KVM will sync
    these registers when it enters the guest, so that accesses from
    guest userspace will work.  The guest kernel, OTOH, must consistently
    use either the real registers or the shared area between exits.  This
    also applies to the already-paravirted SPRG3.
    
    On non-booke, it's not clear to what extent SPRG4-7 are supported
    (they're not architected for book3s, but exist on at least some classic
    chips).  They are copied in the get/set regs ioctls, but I do not see any
    non-booke emulation.  I also do not see any syncing with real registers
    (in PR-mode) including the user-readable SPRG3.  This patch should not
    make that situation any worse.
    Signed-off-by: default avatarScott Wood <scottwood@freescale.com>
    Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
    Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
    b5904972
kvm_e500.h 2.24 KB