From: Jon Doron <arilou@xxxxxxxxx> Sent: Friday, March 13, 2020 6:21 AM
>
> Hyper-V synthetic debugger has two modes, one that uses MSRs and
> the other that use Hypercalls.
>
> Add all the required definitions to both types of synthetic debugger
> interface.
>
> Some of the required new CPUIDs and MSRs are not documented in the TLFS
> so they are in hyperv.h instead.
>
> Signed-off-by: Jon Doron <arilou@xxxxxxxxx>
> ---
> arch/x86/include/asm/hyperv-tlfs.h | 6 ++++++
> arch/x86/kvm/hyperv.h | 22 ++++++++++++++++++++++
> 2 files changed, 28 insertions(+)
>
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index 92abc1e42bfc..671ce2a39d4b 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -131,6 +131,8 @@
> #define HV_FEATURE_FREQUENCY_MSRS_AVAILABLE BIT(8)
> /* Crash MSR available */
> #define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE BIT(10)
> +/* Support for debug MSRs available */
> +#define HV_FEATURE_DEBUG_MSRS_AVAILABLE BIT(11)
> /* stimer Direct Mode is available */
> #define HV_STIMER_DIRECT_MODE_AVAILABLE BIT(19)
>
> @@ -376,6 +378,9 @@ struct hv_tsc_emulation_status {
> #define HVCALL_SEND_IPI_EX 0x0015
> #define HVCALL_POST_MESSAGE 0x005c
> #define HVCALL_SIGNAL_EVENT 0x005d
> +#define HVCALL_POST_DEBUG_DATA 0x0069
> +#define HVCALL_RETRIEVE_DEBUG_DATA 0x006a
> +#define HVCALL_RESET_DEBUG_SESSION 0x006b
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0
>
> @@ -419,6 +424,7 @@ enum HV_GENERIC_SET_FORMAT {
> #define HV_STATUS_INVALID_HYPERCALL_INPUT 3
> #define HV_STATUS_INVALID_ALIGNMENT 4
> #define HV_STATUS_INVALID_PARAMETER 5
> +#define HV_STATUS_OPERATION_DENIED 8
> #define HV_STATUS_INSUFFICIENT_MEMORY 11
> #define HV_STATUS_INVALID_PORT_ID 17
> #define HV_STATUS_INVALID_CONNECTION_ID 18
> diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
> index 757cb578101c..56bc3416b62f 100644
> --- a/arch/x86/kvm/hyperv.h
> +++ b/arch/x86/kvm/hyperv.h
> @@ -23,6 +23,28 @@
>
> #include <linux/kvm_host.h>
>
> +/* These defines are required by KDNet and they are not part of Hyper-V TLFS */
I'm looking for a bit more info in the comment so that it's clear that the
synthetic debugger functionality is not committed to be available going
forward. Perhaps something along the lines of:
/* The #defines related to the synthetic debugger are required by KDNet, but
* they are not documented in the Hyper-V TLFS because the synthetic debugger
* functionality has been deprecated and is subject to removal in future versions
* of Windows.
*/
But with that additional comment text,
Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
> +#define HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS 0x40000080
> +#define HYPERV_CPUID_SYNDBG_INTERFACE 0x40000081
> +#define HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES 0x40000082
> +
> +/*
> + * Hyper-V synthetic debugger platform capabilities
> + * These are HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES.EAX bits.
> + */
> +#define HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING BIT(1)
> +
> +/* Hyper-V Synthetic debug options MSR */
> +#define HV_X64_MSR_SYNDBG_CONTROL 0x400000F1
> +#define HV_X64_MSR_SYNDBG_STATUS 0x400000F2
> +#define HV_X64_MSR_SYNDBG_SEND_BUFFER 0x400000F3
> +#define HV_X64_MSR_SYNDBG_RECV_BUFFER 0x400000F4
> +#define HV_X64_MSR_SYNDBG_PENDING_BUFFER 0x400000F5
> +#define HV_X64_MSR_SYNDBG_OPTIONS 0x400000FF
> +
> +/* Hyper-V HV_X64_MSR_SYNDBG_OPTIONS bits */
> +#define HV_X64_SYNDBG_OPTION_USE_HCALLS BIT(2)
> +
> static inline struct kvm_vcpu_hv *vcpu_to_hv_vcpu(struct kvm_vcpu *vcpu)
> {
> return &vcpu->arch.hyperv;
> --
> 2.24.1
