x86/hyperv: Add smp support for SEV-SNP guest

In the AMD SEV-SNP guest, AP needs to be started up via sev es
save area and Hyper-V requires to call HVCALL_START_VP hypercall
to pass the gpa of sev e

x86/hyperv: Add smp support for SEV-SNP guest

In the AMD SEV-SNP guest, AP needs to be started up via sev es
save area and Hyper-V requires to call HVCALL_START_VP hypercall
to pass the gpa of sev es save area with AP's vp index and VTL(Virtual
trust level) parameters. Override wakeup_secondary_cpu_64 callback
with hv_snp_boot_ap.

Reviewed-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230818102919.1318039-8-ltykernel@gmail.com

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x86/hyperv: Add VTL specific structs and hypercalls

Add structs and hypercalls required to enable VTL support on x86.

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michae

x86/hyperv: Add VTL specific structs and hypercalls

Add structs and hypercalls required to enable VTL support on x86.

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Stanislav Kinsburskii <stanislav.kinsburskii@gmail.com>
Link: https://lore.kernel.org/r/1681192532-15460-3-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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PCI: hv: Enable PCI pass-thru devices in Confidential VMs

For PCI pass-thru devices in a Confidential VM, Hyper-V requires
that PCI config space be accessed via hypercalls. In normal VMs,
config sp

PCI: hv: Enable PCI pass-thru devices in Confidential VMs

For PCI pass-thru devices in a Confidential VM, Hyper-V requires
that PCI config space be accessed via hypercalls. In normal VMs,
config space accesses are trapped to the Hyper-V host and emulated.
But in a confidential VM, the host can't access guest memory to
decode the instruction for emulation, so an explicit hypercall must
be used.

Add functions to make the new MMIO read and MMIO write hypercalls.
Update the PCI config space access functions to use the hypercalls
when such use is indicated by Hyper-V flags. Also, set the flag to
allow the Hyper-V PCI driver to be loaded and used in a Confidential
VM (a.k.a., "Isolation VM"). The driver has previously been hardened
against a malicious Hyper-V host[1].

[1] https://lore.kernel.org/all/20220511223207.3386-2-parri.andrea@gmail.com/

Co-developed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Link: https://lore.kernel.org/r/1679838727-87310-13-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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x86/hyperv: Add an interface to do nested hypercalls

According to TLFS, in order to communicate to L0 hypervisor there needs
to be an additional bit set in the control register. This communication
i

x86/hyperv: Add an interface to do nested hypercalls

According to TLFS, in order to communicate to L0 hypervisor there needs
to be an additional bit set in the control register. This communication
is required to perform privileged instructions which can only be
performed by L0 hypervisor. An example of that could be setting up the
VMBus infrastructure.

Signed-off-by: Jinank Jain <jinankjain@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/24f9d46d5259a688113e6e5e69e21002647f4949.1672639707.git.jinankjain@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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x86/hyperv: Introduce HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants

It may not come clear from where the magical '64' value used in
__cpumask_to_vpset() come from. Moreover, '64' means

x86/hyperv: Introduce HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants

It may not come clear from where the magical '64' value used in
__cpumask_to_vpset() come from. Moreover, '64' means both the maximum
sparse bank number as well as the number of vCPUs per bank. Add defines
to make things clear. These defines are also going to be used by KVM.

No functional change.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-15-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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clocksource/drivers/hyperv: add data structure for reference TSC MSR

Add a data structure to represent the reference TSC MSR similar to
other MSRs. This simplifies the code for updating the MSR.

Si

clocksource/drivers/hyperv: add data structure for reference TSC MSR

Add a data structure to represent the reference TSC MSR similar to
other MSRs. This simplifies the code for updating the MSR.

Signed-off-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20221027095729.1676394-2-anrayabh@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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KVM: x86: Add checks for reserved-to-zero Hyper-V hypercall fields

Add checks for the three fields in Hyper-V's hypercall params that must
be zero. Per the TLFS, HV_STATUS_INVALID_HYPERCALL_INPUT i

KVM: x86: Add checks for reserved-to-zero Hyper-V hypercall fields

Add checks for the three fields in Hyper-V's hypercall params that must
be zero. Per the TLFS, HV_STATUS_INVALID_HYPERCALL_INPUT is returned if
"A reserved bit in the specified hypercall input value is non-zero."

Note, some versions of the TLFS have an off-by-one bug for the last
reserved field, and define it as being bits 64:60. See
https://github.com/MicrosoftDocs/Virtualization-Documentation/pull/1682.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Get the number of Hyper-V sparse banks from the VARHEAD field

Get the number of sparse banks from the VARHEAD field, which the guest is
required to provide as "The size of a variable heade

KVM: x86: Get the number of Hyper-V sparse banks from the VARHEAD field

Get the number of sparse banks from the VARHEAD field, which the guest is
required to provide as "The size of a variable header, in QWORDS.", where
the variable header is:

Variable Header Bytes = {Total Header Bytes - sizeof(Fixed Header)}
rounded up to nearest multiple of 8
Variable HeaderSize = Variable Header Bytes / 8

In other words, the VARHEAD should match the number of sparse banks.
Keep the manual count as a sanity check, but otherwise rely on the field
so as to more closely align with the logic defined in the TLFS and to
allow for future cleanups.

Tweak the tracepoint output to use "rep_cnt" instead of simply "cnt" now
that there is also "var_cnt".

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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PCI: hv: Make the code arch neutral by adding arch specific interfaces

Encapsulate arch dependencies in Hyper-V vPCI through a set of
arch-dependent interfaces. Adding these arch specific interfaces

PCI: hv: Make the code arch neutral by adding arch specific interfaces

Encapsulate arch dependencies in Hyper-V vPCI through a set of
arch-dependent interfaces. Adding these arch specific interfaces will
allow for an implementation for other architectures, such as arm64.

There are no functional changes expected from this patch.

Link: https://lore.kernel.org/r/1641411156-31705-2-git-send-email-sunilmut@linux.microsoft.com
Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>

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x86/hyperv: Add new hvcall guest address host visibility support

Add new hvcall guest address host visibility support to mark
memory visible to host. Call it inside set_memory_decrypted
/encrypted()

x86/hyperv: Add new hvcall guest address host visibility support

Add new hvcall guest address host visibility support to mark
memory visible to host. Call it inside set_memory_decrypted
/encrypted(). Add HYPERVISOR feature check in the
hv_is_isolation_supported() to optimize in non-virtualization
environment.

Acked-by: Dave Hansen <dave.hansen@intel.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/20211025122116.264793-4-ltykernel@gmail.com
[ wei: fix conflicts with tip ]
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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asm-generic/hyperv: add HV_STATUS_ACCESS_DENIED definition

From TLFSv6.0b, this status means: "The caller did not possess sufficient
access rights to perform the requested operation."

Signed-off-by

asm-generic/hyperv: add HV_STATUS_ACCESS_DENIED definition

From TLFSv6.0b, this status means: "The caller did not possess sufficient
access rights to perform the requested operation."

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210521095204.2161214-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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x86/Hyper-V: Support for free page reporting

Linux has support for free page reporting now (36e66c554b5c) for
virtualized environment. On Hyper-V when virtually backed VMs are
configured, Hyper-V wi

x86/Hyper-V: Support for free page reporting

Linux has support for free page reporting now (36e66c554b5c) for
virtualized environment. On Hyper-V when virtually backed VMs are
configured, Hyper-V will advertise cold memory discard capability,
when supported. This patch adds the support to hook into the free
page reporting infrastructure and leverage the Hyper-V cold memory
discard hint hypercall to report/free these pages back to the host.

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Tested-by: Matheus Castello <matheus@castello.eng.br>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/SN4PR2101MB0880121FA4E2FEC67F35C1DCC0649@SN4PR2101MB0880.namprd21.prod.outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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x86/hyper-v: Move hv_message_type to architecture neutral module

The definition of enum hv_message_type includes arch neutral and
x86/x64-specific values. Ideally there would be a way to put the
arc

x86/hyper-v: Move hv_message_type to architecture neutral module

The definition of enum hv_message_type includes arch neutral and
x86/x64-specific values. Ideally there would be a way to put the
arch neutral values in an arch neutral module, and the arch
specific values in an arch specific module. But C doesn't provide
a way to extend enum types. As a compromise, move the entire
definition into an arch neutral module, to avoid duplicating the
arch neutral values for x86/x64 and for ARM64.

No functional change.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/1614721102-2241-3-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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asm-generic/hyperv: import data structures for mapping device interrupts

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-of

asm-generic/hyperv: import data structures for mapping device interrupts

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-15-wei.liu@kernel.org

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asm-generic/hyperv: introduce hv_device_id and auxiliary structures

We will need to identify the device we want Microsoft Hypervisor to
manipulate. Introduce the data structures for that purpose.

asm-generic/hyperv: introduce hv_device_id and auxiliary structures

We will need to identify the device we want Microsoft Hypervisor to
manipulate. Introduce the data structures for that purpose.

They will be used in a later patch.

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-14-wei.liu@kernel.org

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asm-generic/hyperv: update hv_interrupt_entry

We will soon use the same structure to handle IO-APIC interrupts as
well. Introduce an enum to identify the source and a data structure for
IO-APIC RTE.

asm-generic/hyperv: update hv_interrupt_entry

We will soon use the same structure to handle IO-APIC interrupts as
well. Introduce an enum to identify the source and a data structure for
IO-APIC RTE.

While at it, update pci-hyperv.c to use the enum.

No functional change.

Signed-off-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-13-wei.liu@kernel.org

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asm-generic/hyperv: update hv_msi_entry

We will soon need to access fields inside the MSI address and MSI data
fields. Introduce hv_msi_address_register and hv_msi_data_register.

Fix up one user of

asm-generic/hyperv: update hv_msi_entry

We will soon need to access fields inside the MSI address and MSI data
fields. Introduce hv_msi_address_register and hv_msi_data_register.

Fix up one user of hv_msi_entry in mshyperv.h.

No functional change expected.

Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-12-wei.liu@kernel.org

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x86/hyperv: provide a bunch of helper functions

They are used to deposit pages into Microsoft Hypervisor and bring up
logical and virtual processors.

Signed-off-by: Lillian Grassin-Drake <ligrassi@

x86/hyperv: provide a bunch of helper functions

They are used to deposit pages into Microsoft Hypervisor and bring up
logical and virtual processors.

Signed-off-by: Lillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Co-Developed-by: Lillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-10-wei.liu@kernel.org

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x86/hyperv: extract partition ID from Microsoft Hypervisor if necessary

We will need the partition ID for executing some hypercalls later.

Signed-off-by: Lillian Grassin-Drake <ligrassi@microsoft.c

x86/hyperv: extract partition ID from Microsoft Hypervisor if necessary

We will need the partition ID for executing some hypercalls later.

Signed-off-by: Lillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-7-wei.liu@kernel.org

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asm-generic/hyperv: change HV_CPU_POWER_MANAGEMENT to HV_CPU_MANAGEMENT

This makes the name match Hyper-V TLFS.

Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Vitaly Kuznetsov <vkuznets@r

asm-generic/hyperv: change HV_CPU_POWER_MANAGEMENT to HV_CPU_MANAGEMENT

This makes the name match Hyper-V TLFS.

Signed-off-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-2-wei.liu@kernel.org

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x86/hyperv: Load/save the Isolation Configuration leaf

If bit 22 of Group B Features is set, the guest has access to the
Isolation Configuration CPUID leaf. On x86, the first four bits
of EAX in th

x86/hyperv: Load/save the Isolation Configuration leaf

If bit 22 of Group B Features is set, the guest has access to the
Isolation Configuration CPUID leaf. On x86, the first four bits
of EAX in this leaf provide the isolation type of the partition;
we entail three isolation types: 'SNP' (hardware-based isolation),
'VBS' (software-based isolation), and 'NONE' (no isolation).

Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: x86@kernel.org
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20210201144814.2701-2-parri.andrea@gmail.com
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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asm-generic/hyperv: Add definitions for Get/SetVpRegister hypercalls

Add definitions for GetVpRegister and SetVpRegister hypercalls, which
are implemented for both x86 and ARM64.

Signed-off-by: Mic

asm-generic/hyperv: Add definitions for Get/SetVpRegister hypercalls

Add definitions for GetVpRegister and SetVpRegister hypercalls, which
are implemented for both x86 and ARM64.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20200422195737.10223-5-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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x86/hyperv: Split hyperv-tlfs.h into arch dependent and independent files

In preparation for adding ARM64 support, split hyperv-tlfs.h into
architecture dependent and architecture independent files,

x86/hyperv: Split hyperv-tlfs.h into arch dependent and independent files

In preparation for adding ARM64 support, split hyperv-tlfs.h into
architecture dependent and architecture independent files, similar
to what has been done with mshyperv.h. Move architecture independent
definitions into include/asm-generic/hyperv-tlfs.h. The split will
avoid duplicating significant lines of code in the ARM64 version of
hyperv-tlfs.h. The split has no functional impact.

Some of the common definitions have "X64" in the symbol name. Change
these to remove the "X64" in the architecture independent version of
hyperv-tlfs.h, but add aliases with the "X64" in the x86 version so
that x86 code will continue to compile. A later patch set will
change all the references and allow removal of the aliases.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20200422195737.10223-4-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
"ARM:
- Move the arch-specific code into arch/arm64/kvm

- Star

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
"ARM:
- Move the arch-specific code into arch/arm64/kvm

- Start the post-32bit cleanup

- Cherry-pick a few non-invasive pre-NV patches

x86:
- Rework of TLB flushing

- Rework of event injection, especially with respect to nested
virtualization

- Nested AMD event injection facelift, building on the rework of
generic code and fixing a lot of corner cases

- Nested AMD live migration support

- Optimization for TSC deadline MSR writes and IPIs

- Various cleanups

- Asynchronous page fault cleanups (from tglx, common topic branch
with tip tree)

- Interrupt-based delivery of asynchronous "page ready" events (host
side)

- Hyper-V MSRs and hypercalls for guest debugging

- VMX preemption timer fixes

s390:
- Cleanups

Generic:
- switch vCPU thread wakeup from swait to rcuwait

The other architectures, and the guest side of the asynchronous page
fault work, will come next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits)
KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test
KVM: check userspace_addr for all memslots
KVM: selftests: update hyperv_cpuid with SynDBG tests
x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls
x86/kvm/hyper-v: enable hypercalls regardless of hypercall page
x86/kvm/hyper-v: Add support for synthetic debugger interface
x86/hyper-v: Add synthetic debugger definitions
KVM: selftests: VMX preemption timer migration test
KVM: nVMX: Fix VMX preemption timer migration
x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
KVM: x86/pmu: Support full width counting
KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in
KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT
KVM: x86: acknowledgment mechanism for async pf page ready notifications
KVM: x86: interrupt based APF 'page ready' event delivery
KVM: introduce kvm_read_guest_offset_cached()
KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present()
KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info
Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously"
KVM: VMX: Replace zero-length array with flexible-array
...

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asm-generic/hyperv: Add definitions for Get/SetVpRegister hypercalls

Add definitions for GetVpRegister and SetVpRegister hypercalls, which
are implemented for both x86 and ARM64.

asm-generic/hyperv: Add definitions for Get/SetVpRegister hypercalls

Add definitions for GetVpRegister and SetVpRegister hypercalls, which
are implemented for both x86 and ARM64.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20200422195737.10223-5-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

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