On 15/05/2018 13:37, petrutlucia...@gmail.com wrote:
> From: Lucian Petrut <lpet...@cloudbasesolutions.com>
>
> Adds the CPUID trap for CPUID 0x40000000, sending the WHPX signature
> to the guest upon request. This is consistent with other QEMU
> accelerators (KVM).
>
> Signed-off-by: Alessandro Pilotti <apilo...@cloudbasesolutions.com>
> Signed-off-by: Justin Terry (VM) <jute...@microsoft.com>
> Signed-off-by: Lucian Petrut <lpet...@cloudbasesolutions.com>
Is it worth defining a different signature? Can WHPX implement part of
the Hyper-V spec, and if so would it be better to return the Hv
signature ("Hv#1") instead?
Thanks,
Paolo
> ---
> As opposed to the previous patch, this one will set the result of
> this specific CPUID leaf when initializing the accelerator so that
> we avoid a vcpu exit.
>
> target/i386/whpx-all.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/target/i386/whpx-all.c b/target/i386/whpx-all.c
> index 5843517..c8310de 100644
> --- a/target/i386/whpx-all.c
> +++ b/target/i386/whpx-all.c
> @@ -29,6 +29,8 @@
> #include <WinHvPlatform.h>
> #include <WinHvEmulation.h>
>
> +#define WHPX_CPUID_SIGNATURE 0x40000000
> +
> struct whpx_state {
> uint64_t mem_quota;
> WHV_PARTITION_HANDLE partition;
> @@ -1342,6 +1344,27 @@ static int whpx_accel_init(MachineState *ms)
> cpuidExitList,
> RTL_NUMBER_OF(cpuidExitList) *
> sizeof(UINT32));
>
> + UINT32 signature[3] = {0};
> + memcpy(signature, "WHPXWHPXWHPX", 12);
> +
> + WHV_X64_CPUID_RESULT cpuidResultList[1] = {0};
> + cpuidResultList[0].Function = WHPX_CPUID_SIGNATURE;
> + cpuidResultList[0].Eax = 0;
> + cpuidResultList[0].Ebx = signature[0];
> + cpuidResultList[0].Ecx = signature[1];
> + cpuidResultList[0].Edx = signature[2];
> + hr = WHvSetPartitionProperty(whpx->partition,
> + WHvPartitionPropertyCodeCpuidResultList,
> + cpuidResultList,
> + RTL_NUMBER_OF(cpuidResultList) *
> + sizeof(WHV_X64_CPUID_RESULT));
> + if (FAILED(hr)) {
> + error_report("WHPX: Failed to set partition CpuidResultList
> hr=%08lx",
> + hr);
> + ret = -EINVAL;
> + goto error;
> + }
> +
> if (FAILED(hr)) {
> error_report("WHPX: Failed to set partition CpuidExitList hr=%08lx",
> hr);
>
