Re: [PATCH v3] KVM: PPC: Book3S HV: Reserve POWER8 space in get/set_one_reg

[Alexander Graf <agraf@suse.de>]

On 09/03/2013 03:13 AM, Michael Neuling wrote:
> This reserves space in get/set_one_reg ioctl for the extra guest state
> needed for POWER8.  It doesn't implement these at all, it just reserves
> them so that the ABI is defined now.
>
> A few things to note here:
>
> - This add *a lot* state for transactional memory.  TM suspend mode,
>    this is unavoidable, you can't simply roll back all transactions and
>    store only the checkpointed state.  I've added this all to
>    get/set_one_reg (including GPRs) rather than creating a new ioctl
>    which returns a struct kvm_regs like KVM_GET_REGS does.  This means we
>    if we need to extract the TM state, we are going to need a bucket load
>    of IOCTLs.  Hopefully most of the time this will not be needed as we
>    can look at the MSR to see if TM is active and only grab them when
>    needed.  If this becomes a bottle neck in future we can add another
>    ioctl to grab all this state in one go.
>
> - The TM state is offset by 0x80000000.
>
> - For TM, I've done away with VMX and FP and created a single 64x128 bit
>    VSX register space.
>
> - I've left a space of 1 (at 0x9c) since Paulus needs to add a value
>    which applies to POWER7 as well.
>
> Signed-off-by: Michael Neuling<mikey@neuling.org>

Thanks, applied to kvm-ppc-queue.


Alex