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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/virt/kvm/devices
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/virt/kvm/devices')
-rw-r--r--Documentation/virt/kvm/devices/README1
-rw-r--r--Documentation/virt/kvm/devices/arm-vgic-its.rst209
-rw-r--r--Documentation/virt/kvm/devices/arm-vgic-v3.rst291
-rw-r--r--Documentation/virt/kvm/devices/arm-vgic.rst156
-rw-r--r--Documentation/virt/kvm/devices/index.rst19
-rw-r--r--Documentation/virt/kvm/devices/mpic.rst58
-rw-r--r--Documentation/virt/kvm/devices/s390_flic.rst166
-rw-r--r--Documentation/virt/kvm/devices/vcpu.rst163
-rw-r--r--Documentation/virt/kvm/devices/vfio.rst41
-rw-r--r--Documentation/virt/kvm/devices/vm.rst323
-rw-r--r--Documentation/virt/kvm/devices/xics.rst92
-rw-r--r--Documentation/virt/kvm/devices/xive.rst247
12 files changed, 1766 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/devices/README b/Documentation/virt/kvm/devices/README
new file mode 100644
index 000000000..34a698341
--- /dev/null
+++ b/Documentation/virt/kvm/devices/README
@@ -0,0 +1 @@
+This directory contains specific device bindings for KVM_CAP_DEVICE_CTRL.
diff --git a/Documentation/virt/kvm/devices/arm-vgic-its.rst b/Documentation/virt/kvm/devices/arm-vgic-its.rst
new file mode 100644
index 000000000..6c304fd2b
--- /dev/null
+++ b/Documentation/virt/kvm/devices/arm-vgic-its.rst
@@ -0,0 +1,209 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===============================================
+ARM Virtual Interrupt Translation Service (ITS)
+===============================================
+
+Device types supported:
+ KVM_DEV_TYPE_ARM_VGIC_ITS ARM Interrupt Translation Service Controller
+
+The ITS allows MSI(-X) interrupts to be injected into guests. This extension is
+optional. Creating a virtual ITS controller also requires a host GICv3 (see
+arm-vgic-v3.txt), but does not depend on having physical ITS controllers.
+
+There can be multiple ITS controllers per guest, each of them has to have
+a separate, non-overlapping MMIO region.
+
+
+Groups
+======
+
+KVM_DEV_ARM_VGIC_GRP_ADDR
+-------------------------
+
+ Attributes:
+ KVM_VGIC_ITS_ADDR_TYPE (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3 ITS
+ control register frame.
+ This address needs to be 64K aligned and the region covers 128K.
+
+ Errors:
+
+ ======= =================================================
+ -E2BIG Address outside of addressable IPA range
+ -EINVAL Incorrectly aligned address
+ -EEXIST Address already configured
+ -EFAULT Invalid user pointer for attr->addr.
+ -ENODEV Incorrect attribute or the ITS is not supported.
+ ======= =================================================
+
+
+KVM_DEV_ARM_VGIC_GRP_CTRL
+-------------------------
+
+ Attributes:
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the ITS, no additional parameter in
+ kvm_device_attr.addr.
+
+ KVM_DEV_ARM_ITS_CTRL_RESET
+ reset the ITS, no additional parameter in kvm_device_attr.addr.
+ See "ITS Reset State" section.
+
+ KVM_DEV_ARM_ITS_SAVE_TABLES
+ save the ITS table data into guest RAM, at the location provisioned
+ by the guest in corresponding registers/table entries.
+
+ The layout of the tables in guest memory defines an ABI. The entries
+ are laid out in little endian format as described in the last paragraph.
+
+ KVM_DEV_ARM_ITS_RESTORE_TABLES
+ restore the ITS tables from guest RAM to ITS internal structures.
+
+ The GICV3 must be restored before the ITS and all ITS registers but
+ the GITS_CTLR must be restored before restoring the ITS tables.
+
+ The GITS_IIDR read-only register must also be restored before
+ calling KVM_DEV_ARM_ITS_RESTORE_TABLES as the IIDR revision field
+ encodes the ABI revision.
+
+ The expected ordering when restoring the GICv3/ITS is described in section
+ "ITS Restore Sequence".
+
+ Errors:
+
+ ======= ==========================================================
+ -ENXIO ITS not properly configured as required prior to setting
+ this attribute
+ -ENOMEM Memory shortage when allocating ITS internal data
+ -EINVAL Inconsistent restored data
+ -EFAULT Invalid guest ram access
+ -EBUSY One or more VCPUS are running
+ -EACCES The virtual ITS is backed by a physical GICv4 ITS, and the
+ state is not available
+ ======= ==========================================================
+
+KVM_DEV_ARM_VGIC_GRP_ITS_REGS
+-----------------------------
+
+ Attributes:
+ The attr field of kvm_device_attr encodes the offset of the
+ ITS register, relative to the ITS control frame base address
+ (ITS_base).
+
+ kvm_device_attr.addr points to a __u64 value whatever the width
+ of the addressed register (32/64 bits). 64 bit registers can only
+ be accessed with full length.
+
+ Writes to read-only registers are ignored by the kernel except for:
+
+ - GITS_CREADR. It must be restored otherwise commands in the queue
+ will be re-executed after restoring CWRITER. GITS_CREADR must be
+ restored before restoring the GITS_CTLR which is likely to enable the
+ ITS. Also it must be restored after GITS_CBASER since a write to
+ GITS_CBASER resets GITS_CREADR.
+ - GITS_IIDR. The Revision field encodes the table layout ABI revision.
+ In the future we might implement direct injection of virtual LPIs.
+ This will require an upgrade of the table layout and an evolution of
+ the ABI. GITS_IIDR must be restored before calling
+ KVM_DEV_ARM_ITS_RESTORE_TABLES.
+
+ For other registers, getting or setting a register has the same
+ effect as reading/writing the register on real hardware.
+
+ Errors:
+
+ ======= ====================================================
+ -ENXIO Offset does not correspond to any supported register
+ -EFAULT Invalid user pointer for attr->addr
+ -EINVAL Offset is not 64-bit aligned
+ -EBUSY one or more VCPUS are running
+ ======= ====================================================
+
+ITS Restore Sequence:
+---------------------
+
+The following ordering must be followed when restoring the GIC and the ITS:
+
+a) restore all guest memory and create vcpus
+b) restore all redistributors
+c) provide the ITS base address
+ (KVM_DEV_ARM_VGIC_GRP_ADDR)
+d) restore the ITS in the following order:
+
+ 1. Restore GITS_CBASER
+ 2. Restore all other ``GITS_`` registers, except GITS_CTLR!
+ 3. Load the ITS table data (KVM_DEV_ARM_ITS_RESTORE_TABLES)
+ 4. Restore GITS_CTLR
+
+Then vcpus can be started.
+
+ITS Table ABI REV0:
+-------------------
+
+ Revision 0 of the ABI only supports the features of a virtual GICv3, and does
+ not support a virtual GICv4 with support for direct injection of virtual
+ interrupts for nested hypervisors.
+
+ The device table and ITT are indexed by the DeviceID and EventID,
+ respectively. The collection table is not indexed by CollectionID, and the
+ entries in the collection are listed in no particular order.
+ All entries are 8 bytes.
+
+ Device Table Entry (DTE)::
+
+ bits: | 63| 62 ... 49 | 48 ... 5 | 4 ... 0 |
+ values: | V | next | ITT_addr | Size |
+
+ where:
+
+ - V indicates whether the entry is valid. If not, other fields
+ are not meaningful.
+ - next: equals to 0 if this entry is the last one; otherwise it
+ corresponds to the DeviceID offset to the next DTE, capped by
+ 2^14 -1.
+ - ITT_addr matches bits [51:8] of the ITT address (256 Byte aligned).
+ - Size specifies the supported number of bits for the EventID,
+ minus one
+
+ Collection Table Entry (CTE)::
+
+ bits: | 63| 62 .. 52 | 51 ... 16 | 15 ... 0 |
+ values: | V | RES0 | RDBase | ICID |
+
+ where:
+
+ - V indicates whether the entry is valid. If not, other fields are
+ not meaningful.
+ - RES0: reserved field with Should-Be-Zero-or-Preserved behavior.
+ - RDBase is the PE number (GICR_TYPER.Processor_Number semantic),
+ - ICID is the collection ID
+
+ Interrupt Translation Entry (ITE)::
+
+ bits: | 63 ... 48 | 47 ... 16 | 15 ... 0 |
+ values: | next | pINTID | ICID |
+
+ where:
+
+ - next: equals to 0 if this entry is the last one; otherwise it corresponds
+ to the EventID offset to the next ITE capped by 2^16 -1.
+ - pINTID is the physical LPI ID; if zero, it means the entry is not valid
+ and other fields are not meaningful.
+ - ICID is the collection ID
+
+ITS Reset State:
+----------------
+
+RESET returns the ITS to the same state that it was when first created and
+initialized. When the RESET command returns, the following things are
+guaranteed:
+
+- The ITS is not enabled and quiescent
+ GITS_CTLR.Enabled = 0 .Quiescent=1
+- There is no internally cached state
+- No collection or device table are used
+ GITS_BASER<n>.Valid = 0
+- GITS_CBASER = 0, GITS_CREADR = 0, GITS_CWRITER = 0
+- The ABI version is unchanged and remains the one set when the ITS
+ device was first created.
diff --git a/Documentation/virt/kvm/devices/arm-vgic-v3.rst b/Documentation/virt/kvm/devices/arm-vgic-v3.rst
new file mode 100644
index 000000000..5dd3bff51
--- /dev/null
+++ b/Documentation/virt/kvm/devices/arm-vgic-v3.rst
@@ -0,0 +1,291 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================================================
+ARM Virtual Generic Interrupt Controller v3 and later (VGICv3)
+==============================================================
+
+
+Device types supported:
+ - KVM_DEV_TYPE_ARM_VGIC_V3 ARM Generic Interrupt Controller v3.0
+
+Only one VGIC instance may be instantiated through this API. The created VGIC
+will act as the VM interrupt controller, requiring emulated user-space devices
+to inject interrupts to the VGIC instead of directly to CPUs. It is not
+possible to create both a GICv3 and GICv2 on the same VM.
+
+Creating a guest GICv3 device requires a host GICv3 as well.
+
+
+Groups:
+ KVM_DEV_ARM_VGIC_GRP_ADDR
+ Attributes:
+
+ KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3 distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned and the region covers 64 KByte.
+
+ KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3
+ redistributor register mappings. There are two 64K pages for each
+ VCPU and all of the redistributor pages are contiguous.
+ Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned.
+
+ KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION (rw, 64-bit)
+ The attribute data pointed to by kvm_device_attr.addr is a __u64 value::
+
+ bits: | 63 .... 52 | 51 .... 16 | 15 - 12 |11 - 0
+ values: | count | base | flags | index
+
+ - index encodes the unique redistributor region index
+ - flags: reserved for future use, currently 0
+ - base field encodes bits [51:16] of the guest physical base address
+ of the first redistributor in the region.
+ - count encodes the number of redistributors in the region. Must be
+ greater than 0.
+
+ There are two 64K pages for each redistributor in the region and
+ redistributors are laid out contiguously within the region. Regions
+ are filled with redistributors in the index order. The sum of all
+ region count fields must be greater than or equal to the number of
+ VCPUs. Redistributor regions must be registered in the incremental
+ index order, starting from index 0.
+
+ The characteristics of a specific redistributor region can be read
+ by presetting the index field in the attr data.
+ Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+
+ It is invalid to mix calls with KVM_VGIC_V3_ADDR_TYPE_REDIST and
+ KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attributes.
+
+ Errors:
+
+ ======= =============================================================
+ -E2BIG Address outside of addressable IPA range
+ -EINVAL Incorrectly aligned address, bad redistributor region
+ count/index, mixed redistributor region attribute usage
+ -EEXIST Address already configured
+ -ENOENT Attempt to read the characteristics of a non existing
+ redistributor region
+ -ENXIO The group or attribute is unknown/unsupported for this device
+ or hardware support is missing.
+ -EFAULT Invalid user pointer for attr->addr.
+ ======= =============================================================
+
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS, KVM_DEV_ARM_VGIC_GRP_REDIST_REGS
+ Attributes:
+
+ The attr field of kvm_device_attr encodes two values::
+
+ bits: | 63 .... 32 | 31 .... 0 |
+ values: | mpidr | offset |
+
+ All distributor regs are (rw, 32-bit) and kvm_device_attr.addr points to a
+ __u32 value. 64-bit registers must be accessed by separately accessing the
+ lower and higher word.
+
+ Writes to read-only registers are ignored by the kernel.
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS accesses the main distributor registers.
+ KVM_DEV_ARM_VGIC_GRP_REDIST_REGS accesses the redistributor of the CPU
+ specified by the mpidr.
+
+ The offset is relative to the "[Re]Distributor base address" as defined
+ in the GICv3/4 specs. Getting or setting such a register has the same
+ effect as reading or writing the register on real hardware, except for the
+ following registers: GICD_STATUSR, GICR_STATUSR, GICD_ISPENDR,
+ GICR_ISPENDR0, GICD_ICPENDR, and GICR_ICPENDR0. These registers behave
+ differently when accessed via this interface compared to their
+ architecturally defined behavior to allow software a full view of the
+ VGIC's internal state.
+
+ The mpidr field is used to specify which
+ redistributor is accessed. The mpidr is ignored for the distributor.
+
+ The mpidr encoding is based on the affinity information in the
+ architecture defined MPIDR, and the field is encoded as follows::
+
+ | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+ | Aff3 | Aff2 | Aff1 | Aff0 |
+
+ Note that distributor fields are not banked, but return the same value
+ regardless of the mpidr used to access the register.
+
+ GICD_IIDR.Revision is updated when the KVM implementation is changed in a
+ way directly observable by the guest or userspace. Userspace should read
+ GICD_IIDR from KVM and write back the read value to confirm its expected
+ behavior is aligned with the KVM implementation. Userspace should set
+ GICD_IIDR before setting any other registers to ensure the expected
+ behavior.
+
+
+ The GICD_STATUSR and GICR_STATUSR registers are architecturally defined such
+ that a write of a clear bit has no effect, whereas a write with a set bit
+ clears that value. To allow userspace to freely set the values of these two
+ registers, setting the attributes with the register offsets for these two
+ registers simply sets the non-reserved bits to the value written.
+
+
+ Accesses (reads and writes) to the GICD_ISPENDR register region and
+ GICR_ISPENDR0 registers get/set the value of the latched pending state for
+ the interrupts.
+
+ This is identical to the value returned by a guest read from ISPENDR for an
+ edge triggered interrupt, but may differ for level triggered interrupts.
+ For edge triggered interrupts, once an interrupt becomes pending (whether
+ because of an edge detected on the input line or because of a guest write
+ to ISPENDR) this state is "latched", and only cleared when either the
+ interrupt is activated or when the guest writes to ICPENDR. A level
+ triggered interrupt may be pending either because the level input is held
+ high by a device, or because of a guest write to the ISPENDR register. Only
+ ISPENDR writes are latched; if the device lowers the line level then the
+ interrupt is no longer pending unless the guest also wrote to ISPENDR, and
+ conversely writes to ICPENDR or activations of the interrupt do not clear
+ the pending status if the line level is still being held high. (These
+ rules are documented in the GICv3 specification descriptions of the ICPENDR
+ and ISPENDR registers.) For a level triggered interrupt the value accessed
+ here is that of the latch which is set by ISPENDR and cleared by ICPENDR or
+ interrupt activation, whereas the value returned by a guest read from
+ ISPENDR is the logical OR of the latch value and the input line level.
+
+ Raw access to the latch state is provided to userspace so that it can save
+ and restore the entire GIC internal state (which is defined by the
+ combination of the current input line level and the latch state, and cannot
+ be deduced from purely the line level and the value of the ISPENDR
+ registers).
+
+ Accesses to GICD_ICPENDR register region and GICR_ICPENDR0 registers have
+ RAZ/WI semantics, meaning that reads always return 0 and writes are always
+ ignored.
+
+ Errors:
+
+ ====== =====================================================
+ -ENXIO Getting or setting this register is not yet supported
+ -EBUSY One or more VCPUs are running
+ ====== =====================================================
+
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS
+ Attributes:
+
+ The attr field of kvm_device_attr encodes two values::
+
+ bits: | 63 .... 32 | 31 .... 16 | 15 .... 0 |
+ values: | mpidr | RES | instr |
+
+ The mpidr field encodes the CPU ID based on the affinity information in the
+ architecture defined MPIDR, and the field is encoded as follows::
+
+ | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+ | Aff3 | Aff2 | Aff1 | Aff0 |
+
+ The instr field encodes the system register to access based on the fields
+ defined in the A64 instruction set encoding for system register access
+ (RES means the bits are reserved for future use and should be zero)::
+
+ | 15 ... 14 | 13 ... 11 | 10 ... 7 | 6 ... 3 | 2 ... 0 |
+ | Op 0 | Op1 | CRn | CRm | Op2 |
+
+ All system regs accessed through this API are (rw, 64-bit) and
+ kvm_device_attr.addr points to a __u64 value.
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS accesses the CPU interface registers for the
+ CPU specified by the mpidr field.
+
+ CPU interface registers access is not implemented for AArch32 mode.
+ Error -ENXIO is returned when accessed in AArch32 mode.
+
+ Errors:
+
+ ======= =====================================================
+ -ENXIO Getting or setting this register is not yet supported
+ -EBUSY VCPU is running
+ -EINVAL Invalid mpidr or register value supplied
+ ======= =====================================================
+
+
+ KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+ Attributes:
+
+ A value describing the number of interrupts (SGI, PPI and SPI) for
+ this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+ kvm_device_attr.addr points to a __u32 value.
+
+ Errors:
+
+ ======= ======================================
+ -EINVAL Value set is out of the expected range
+ -EBUSY Value has already be set.
+ ======= ======================================
+
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the VGIC, no additional parameter in
+ kvm_device_attr.addr.
+ KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES
+ save all LPI pending bits into guest RAM pending tables.
+
+ The first kB of the pending table is not altered by this operation.
+
+ Errors:
+
+ ======= ========================================================
+ -ENXIO VGIC not properly configured as required prior to calling
+ this attribute
+ -ENODEV no online VCPU
+ -ENOMEM memory shortage when allocating vgic internal data
+ -EFAULT Invalid guest ram access
+ -EBUSY One or more VCPUS are running
+ ======= ========================================================
+
+
+ KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO
+ Attributes:
+
+ The attr field of kvm_device_attr encodes the following values::
+
+ bits: | 63 .... 32 | 31 .... 10 | 9 .... 0 |
+ values: | mpidr | info | vINTID |
+
+ The vINTID specifies which set of IRQs is reported on.
+
+ The info field specifies which information userspace wants to get or set
+ using this interface. Currently we support the following info values:
+
+ VGIC_LEVEL_INFO_LINE_LEVEL:
+ Get/Set the input level of the IRQ line for a set of 32 contiguously
+ numbered interrupts.
+
+ vINTID must be a multiple of 32.
+
+ kvm_device_attr.addr points to a __u32 value which will contain a
+ bitmap where a set bit means the interrupt level is asserted.
+
+ Bit[n] indicates the status for interrupt vINTID + n.
+
+ SGIs and any interrupt with a higher ID than the number of interrupts
+ supported, will be RAZ/WI. LPIs are always edge-triggered and are
+ therefore not supported by this interface.
+
+ PPIs are reported per VCPU as specified in the mpidr field, and SPIs are
+ reported with the same value regardless of the mpidr specified.
+
+ The mpidr field encodes the CPU ID based on the affinity information in the
+ architecture defined MPIDR, and the field is encoded as follows::
+
+ | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+ | Aff3 | Aff2 | Aff1 | Aff0 |
+
+ Errors:
+
+ ======= =============================================
+ -EINVAL vINTID is not multiple of 32 or info field is
+ not VGIC_LEVEL_INFO_LINE_LEVEL
+ ======= =============================================
diff --git a/Documentation/virt/kvm/devices/arm-vgic.rst b/Documentation/virt/kvm/devices/arm-vgic.rst
new file mode 100644
index 000000000..40bdeea1d
--- /dev/null
+++ b/Documentation/virt/kvm/devices/arm-vgic.rst
@@ -0,0 +1,156 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==================================================
+ARM Virtual Generic Interrupt Controller v2 (VGIC)
+==================================================
+
+Device types supported:
+
+ - KVM_DEV_TYPE_ARM_VGIC_V2 ARM Generic Interrupt Controller v2.0
+
+Only one VGIC instance may be instantiated through either this API or the
+legacy KVM_CREATE_IRQCHIP API. The created VGIC will act as the VM interrupt
+controller, requiring emulated user-space devices to inject interrupts to the
+VGIC instead of directly to CPUs.
+
+GICv3 implementations with hardware compatibility support allow creating a
+guest GICv2 through this interface. For information on creating a guest GICv3
+device and guest ITS devices, see arm-vgic-v3.txt. It is not possible to
+create both a GICv3 and GICv2 device on the same VM.
+
+
+Groups:
+ KVM_DEV_ARM_VGIC_GRP_ADDR
+ Attributes:
+
+ KVM_VGIC_V2_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GIC distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit)
+ Base address in the guest physical address space of the GIC virtual cpu
+ interface register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ Errors:
+
+ ======= =============================================================
+ -E2BIG Address outside of addressable IPA range
+ -EINVAL Incorrectly aligned address
+ -EEXIST Address already configured
+ -ENXIO The group or attribute is unknown/unsupported for this device
+ or hardware support is missing.
+ -EFAULT Invalid user pointer for attr->addr.
+ ======= =============================================================
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS
+ Attributes:
+
+ The attr field of kvm_device_attr encodes two values::
+
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | vcpu_index | offset |
+
+ All distributor regs are (rw, 32-bit)
+
+ The offset is relative to the "Distributor base address" as defined in the
+ GICv2 specs. Getting or setting such a register has the same effect as
+ reading or writing the register on the actual hardware from the cpu whose
+ index is specified with the vcpu_index field. Note that most distributor
+ fields are not banked, but return the same value regardless of the
+ vcpu_index used to access the register.
+
+ GICD_IIDR.Revision is updated when the KVM implementation of an emulated
+ GICv2 is changed in a way directly observable by the guest or userspace.
+ Userspace should read GICD_IIDR from KVM and write back the read value to
+ confirm its expected behavior is aligned with the KVM implementation.
+ Userspace should set GICD_IIDR before setting any other registers (both
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_CPU_REGS) to ensure
+ the expected behavior. Unless GICD_IIDR has been set from userspace, writes
+ to the interrupt group registers (GICD_IGROUPR) are ignored.
+
+ Errors:
+
+ ======= =====================================================
+ -ENXIO Getting or setting this register is not yet supported
+ -EBUSY One or more VCPUs are running
+ -EINVAL Invalid vcpu_index supplied
+ ======= =====================================================
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_REGS
+ Attributes:
+
+ The attr field of kvm_device_attr encodes two values::
+
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | vcpu_index | offset |
+
+ All CPU interface regs are (rw, 32-bit)
+
+ The offset specifies the offset from the "CPU interface base address" as
+ defined in the GICv2 specs. Getting or setting such a register has the
+ same effect as reading or writing the register on the actual hardware.
+
+ The Active Priorities Registers APRn are implementation defined, so we set a
+ fixed format for our implementation that fits with the model of a "GICv2
+ implementation without the security extensions" which we present to the
+ guest. This interface always exposes four register APR[0-3] describing the
+ maximum possible 128 preemption levels. The semantics of the register
+ indicate if any interrupts in a given preemption level are in the active
+ state by setting the corresponding bit.
+
+ Thus, preemption level X has one or more active interrupts if and only if:
+
+ APRn[X mod 32] == 0b1, where n = X / 32
+
+ Bits for undefined preemption levels are RAZ/WI.
+
+ Note that this differs from a CPU's view of the APRs on hardware in which
+ a GIC without the security extensions expose group 0 and group 1 active
+ priorities in separate register groups, whereas we show a combined view
+ similar to GICv2's GICH_APR.
+
+ For historical reasons and to provide ABI compatibility with userspace we
+ export the GICC_PMR register in the format of the GICH_VMCR.VMPriMask
+ field in the lower 5 bits of a word, meaning that userspace must always
+ use the lower 5 bits to communicate with the KVM device and must shift the
+ value left by 3 places to obtain the actual priority mask level.
+
+ Errors:
+
+ ======= =====================================================
+ -ENXIO Getting or setting this register is not yet supported
+ -EBUSY One or more VCPUs are running
+ -EINVAL Invalid vcpu_index supplied
+ ======= =====================================================
+
+ KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+ Attributes:
+
+ A value describing the number of interrupts (SGI, PPI and SPI) for
+ this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+ Errors:
+
+ ======= =============================================================
+ -EINVAL Value set is out of the expected range
+ -EBUSY Value has already be set, or GIC has already been initialized
+ with default values.
+ ======= =============================================================
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the VGIC or ITS, no additional parameter
+ in kvm_device_attr.addr.
+
+ Errors:
+
+ ======= =========================================================
+ -ENXIO VGIC not properly configured as required prior to calling
+ this attribute
+ -ENODEV no online VCPU
+ -ENOMEM memory shortage when allocating vgic internal data
+ ======= =========================================================
diff --git a/Documentation/virt/kvm/devices/index.rst b/Documentation/virt/kvm/devices/index.rst
new file mode 100644
index 000000000..192cda740
--- /dev/null
+++ b/Documentation/virt/kvm/devices/index.rst
@@ -0,0 +1,19 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=======
+Devices
+=======
+
+.. toctree::
+ :maxdepth: 2
+
+ arm-vgic-its
+ arm-vgic
+ arm-vgic-v3
+ mpic
+ s390_flic
+ vcpu
+ vfio
+ vm
+ xics
+ xive
diff --git a/Documentation/virt/kvm/devices/mpic.rst b/Documentation/virt/kvm/devices/mpic.rst
new file mode 100644
index 000000000..55cefe030
--- /dev/null
+++ b/Documentation/virt/kvm/devices/mpic.rst
@@ -0,0 +1,58 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+MPIC interrupt controller
+=========================
+
+Device types supported:
+
+ - KVM_DEV_TYPE_FSL_MPIC_20 Freescale MPIC v2.0
+ - KVM_DEV_TYPE_FSL_MPIC_42 Freescale MPIC v4.2
+
+Only one MPIC instance, of any type, may be instantiated. The created
+MPIC will act as the system interrupt controller, connecting to each
+vcpu's interrupt inputs.
+
+Groups:
+ KVM_DEV_MPIC_GRP_MISC
+ Attributes:
+
+ KVM_DEV_MPIC_BASE_ADDR (rw, 64-bit)
+ Base address of the 256 KiB MPIC register space. Must be
+ naturally aligned. A value of zero disables the mapping.
+ Reset value is zero.
+
+ KVM_DEV_MPIC_GRP_REGISTER (rw, 32-bit)
+ Access an MPIC register, as if the access were made from the guest.
+ "attr" is the byte offset into the MPIC register space. Accesses
+ must be 4-byte aligned.
+
+ MSIs may be signaled by using this attribute group to write
+ to the relevant MSIIR.
+
+ KVM_DEV_MPIC_GRP_IRQ_ACTIVE (rw, 32-bit)
+ IRQ input line for each standard openpic source. 0 is inactive and 1
+ is active, regardless of interrupt sense.
+
+ For edge-triggered interrupts: Writing 1 is considered an activating
+ edge, and writing 0 is ignored. Reading returns 1 if a previously
+ signaled edge has not been acknowledged, and 0 otherwise.
+
+ "attr" is the IRQ number. IRQ numbers for standard sources are the
+ byte offset of the relevant IVPR from EIVPR0, divided by 32.
+
+IRQ Routing:
+
+ The MPIC emulation supports IRQ routing. Only a single MPIC device can
+ be instantiated. Once that device has been created, it's available as
+ irqchip id 0.
+
+ This irqchip 0 has 256 interrupt pins, which expose the interrupts in
+ the main array of interrupt sources (a.k.a. "SRC" interrupts).
+
+ The numbering is the same as the MPIC device tree binding -- based on
+ the register offset from the beginning of the sources array, without
+ regard to any subdivisions in chip documentation such as "internal"
+ or "external" interrupts.
+
+ Access to non-SRC interrupts is not implemented through IRQ routing mechanisms.
diff --git a/Documentation/virt/kvm/devices/s390_flic.rst b/Documentation/virt/kvm/devices/s390_flic.rst
new file mode 100644
index 000000000..ea96559ba
--- /dev/null
+++ b/Documentation/virt/kvm/devices/s390_flic.rst
@@ -0,0 +1,166 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+====================================
+FLIC (floating interrupt controller)
+====================================
+
+FLIC handles floating (non per-cpu) interrupts, i.e. I/O, service and some
+machine check interruptions. All interrupts are stored in a per-vm list of
+pending interrupts. FLIC performs operations on this list.
+
+Only one FLIC instance may be instantiated.
+
+FLIC provides support to
+- add interrupts (KVM_DEV_FLIC_ENQUEUE)
+- inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS)
+- purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS)
+- purge one pending floating I/O interrupt (KVM_DEV_FLIC_CLEAR_IO_IRQ)
+- enable/disable for the guest transparent async page faults
+- register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*)
+- modify AIS (adapter-interruption-suppression) mode state (KVM_DEV_FLIC_AISM)
+- inject adapter interrupts on a specified adapter (KVM_DEV_FLIC_AIRQ_INJECT)
+- get/set all AIS mode states (KVM_DEV_FLIC_AISM_ALL)
+
+Groups:
+ KVM_DEV_FLIC_ENQUEUE
+ Passes a buffer and length into the kernel which are then injected into
+ the list of pending interrupts.
+ attr->addr contains the pointer to the buffer and attr->attr contains
+ the length of the buffer.
+ The format of the data structure kvm_s390_irq as it is copied from userspace
+ is defined in usr/include/linux/kvm.h.
+
+ KVM_DEV_FLIC_GET_ALL_IRQS
+ Copies all floating interrupts into a buffer provided by userspace.
+ When the buffer is too small it returns -ENOMEM, which is the indication
+ for userspace to try again with a bigger buffer.
+
+ -ENOBUFS is returned when the allocation of a kernelspace buffer has
+ failed.
+
+ -EFAULT is returned when copying data to userspace failed.
+ All interrupts remain pending, i.e. are not deleted from the list of
+ currently pending interrupts.
+ attr->addr contains the userspace address of the buffer into which all
+ interrupt data will be copied.
+ attr->attr contains the size of the buffer in bytes.
+
+ KVM_DEV_FLIC_CLEAR_IRQS
+ Simply deletes all elements from the list of currently pending floating
+ interrupts. No interrupts are injected into the guest.
+
+ KVM_DEV_FLIC_CLEAR_IO_IRQ
+ Deletes one (if any) I/O interrupt for a subchannel identified by the
+ subsystem identification word passed via the buffer specified by
+ attr->addr (address) and attr->attr (length).
+
+ KVM_DEV_FLIC_APF_ENABLE
+ Enables async page faults for the guest. So in case of a major page fault
+ the host is allowed to handle this async and continues the guest.
+
+ KVM_DEV_FLIC_APF_DISABLE_WAIT
+ Disables async page faults for the guest and waits until already pending
+ async page faults are done. This is necessary to trigger a completion interrupt
+ for every init interrupt before migrating the interrupt list.
+
+ KVM_DEV_FLIC_ADAPTER_REGISTER
+ Register an I/O adapter interrupt source. Takes a kvm_s390_io_adapter
+ describing the adapter to register::
+
+ struct kvm_s390_io_adapter {
+ __u32 id;
+ __u8 isc;
+ __u8 maskable;
+ __u8 swap;
+ __u8 flags;
+ };
+
+ id contains the unique id for the adapter, isc the I/O interruption subclass
+ to use, maskable whether this adapter may be masked (interrupts turned off),
+ swap whether the indicators need to be byte swapped, and flags contains
+ further characteristics of the adapter.
+
+ Currently defined values for 'flags' are:
+
+ - KVM_S390_ADAPTER_SUPPRESSIBLE: adapter is subject to AIS
+ (adapter-interrupt-suppression) facility. This flag only has an effect if
+ the AIS capability is enabled.
+
+ Unknown flag values are ignored.
+
+
+ KVM_DEV_FLIC_ADAPTER_MODIFY
+ Modifies attributes of an existing I/O adapter interrupt source. Takes
+ a kvm_s390_io_adapter_req specifying the adapter and the operation::
+
+ struct kvm_s390_io_adapter_req {
+ __u32 id;
+ __u8 type;
+ __u8 mask;
+ __u16 pad0;
+ __u64 addr;
+ };
+
+ id specifies the adapter and type the operation. The supported operations
+ are:
+
+ KVM_S390_IO_ADAPTER_MASK
+ mask or unmask the adapter, as specified in mask
+
+ KVM_S390_IO_ADAPTER_MAP
+ This is now a no-op. The mapping is purely done by the irq route.
+ KVM_S390_IO_ADAPTER_UNMAP
+ This is now a no-op. The mapping is purely done by the irq route.
+
+ KVM_DEV_FLIC_AISM
+ modify the adapter-interruption-suppression mode for a given isc if the
+ AIS capability is enabled. Takes a kvm_s390_ais_req describing::
+
+ struct kvm_s390_ais_req {
+ __u8 isc;
+ __u16 mode;
+ };
+
+ isc contains the target I/O interruption subclass, mode the target
+ adapter-interruption-suppression mode. The following modes are
+ currently supported:
+
+ - KVM_S390_AIS_MODE_ALL: ALL-Interruptions Mode, i.e. airq injection
+ is always allowed;
+ - KVM_S390_AIS_MODE_SINGLE: SINGLE-Interruption Mode, i.e. airq
+ injection is only allowed once and the following adapter interrupts
+ will be suppressed until the mode is set again to ALL-Interruptions
+ or SINGLE-Interruption mode.
+
+ KVM_DEV_FLIC_AIRQ_INJECT
+ Inject adapter interrupts on a specified adapter.
+ attr->attr contains the unique id for the adapter, which allows for
+ adapter-specific checks and actions.
+ For adapters subject to AIS, handle the airq injection suppression for
+ an isc according to the adapter-interruption-suppression mode on condition
+ that the AIS capability is enabled.
+
+ KVM_DEV_FLIC_AISM_ALL
+ Gets or sets the adapter-interruption-suppression mode for all ISCs. Takes
+ a kvm_s390_ais_all describing::
+
+ struct kvm_s390_ais_all {
+ __u8 simm; /* Single-Interruption-Mode mask */
+ __u8 nimm; /* No-Interruption-Mode mask *
+ };
+
+ simm contains Single-Interruption-Mode mask for all ISCs, nimm contains
+ No-Interruption-Mode mask for all ISCs. Each bit in simm and nimm corresponds
+ to an ISC (MSB0 bit 0 to ISC 0 and so on). The combination of simm bit and
+ nimm bit presents AIS mode for a ISC.
+
+ KVM_DEV_FLIC_AISM_ALL is indicated by KVM_CAP_S390_AIS_MIGRATION.
+
+Note: The KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR device ioctls executed on
+FLIC with an unknown group or attribute gives the error code EINVAL (instead of
+ENXIO, as specified in the API documentation). It is not possible to conclude
+that a FLIC operation is unavailable based on the error code resulting from a
+usage attempt.
+
+.. note:: The KVM_DEV_FLIC_CLEAR_IO_IRQ ioctl will return EINVAL in case a
+ zero schid is specified.
diff --git a/Documentation/virt/kvm/devices/vcpu.rst b/Documentation/virt/kvm/devices/vcpu.rst
new file mode 100644
index 000000000..2acec3b9e
--- /dev/null
+++ b/Documentation/virt/kvm/devices/vcpu.rst
@@ -0,0 +1,163 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================
+Generic vcpu interface
+======================
+
+The virtual cpu "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
+KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same struct
+kvm_device_attr as other devices, but targets VCPU-wide settings and controls.
+
+The groups and attributes per virtual cpu, if any, are architecture specific.
+
+1. GROUP: KVM_ARM_VCPU_PMU_V3_CTRL
+==================================
+
+:Architectures: ARM64
+
+1.1. ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_IRQ
+---------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address for PMU overflow interrupt is a
+ pointer to an int
+
+Returns:
+
+ ======= ========================================================
+ -EBUSY The PMU overflow interrupt is already set
+ -EFAULT Error reading interrupt number
+ -ENXIO PMUv3 not supported or the overflow interrupt not set
+ when attempting to get it
+ -ENODEV KVM_ARM_VCPU_PMU_V3 feature missing from VCPU
+ -EINVAL Invalid PMU overflow interrupt number supplied or
+ trying to set the IRQ number without using an in-kernel
+ irqchip.
+ ======= ========================================================
+
+A value describing the PMUv3 (Performance Monitor Unit v3) overflow interrupt
+number for this vcpu. This interrupt could be a PPI or SPI, but the interrupt
+type must be same for each vcpu. As a PPI, the interrupt number is the same for
+all vcpus, while as an SPI it must be a separate number per vcpu.
+
+1.2 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_INIT
+---------------------------------------
+
+:Parameters: no additional parameter in kvm_device_attr.addr
+
+Returns:
+
+ ======= ======================================================
+ -EEXIST Interrupt number already used
+ -ENODEV PMUv3 not supported or GIC not initialized
+ -ENXIO PMUv3 not supported, missing VCPU feature or interrupt
+ number not set
+ -EBUSY PMUv3 already initialized
+ ======= ======================================================
+
+Request the initialization of the PMUv3. If using the PMUv3 with an in-kernel
+virtual GIC implementation, this must be done after initializing the in-kernel
+irqchip.
+
+1.3 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_FILTER
+-----------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address for a PMU event filter is a
+ pointer to a struct kvm_pmu_event_filter
+
+:Returns:
+
+ ======= ======================================================
+ -ENODEV PMUv3 not supported or GIC not initialized
+ -ENXIO PMUv3 not properly configured or in-kernel irqchip not
+ configured as required prior to calling this attribute
+ -EBUSY PMUv3 already initialized
+ -EINVAL Invalid filter range
+ ======= ======================================================
+
+Request the installation of a PMU event filter described as follows::
+
+ struct kvm_pmu_event_filter {
+ __u16 base_event;
+ __u16 nevents;
+
+ #define KVM_PMU_EVENT_ALLOW 0
+ #define KVM_PMU_EVENT_DENY 1
+
+ __u8 action;
+ __u8 pad[3];
+ };
+
+A filter range is defined as the range [@base_event, @base_event + @nevents),
+together with an @action (KVM_PMU_EVENT_ALLOW or KVM_PMU_EVENT_DENY). The
+first registered range defines the global policy (global ALLOW if the first
+@action is DENY, global DENY if the first @action is ALLOW). Multiple ranges
+can be programmed, and must fit within the event space defined by the PMU
+architecture (10 bits on ARMv8.0, 16 bits from ARMv8.1 onwards).
+
+Note: "Cancelling" a filter by registering the opposite action for the same
+range doesn't change the default action. For example, installing an ALLOW
+filter for event range [0:10) as the first filter and then applying a DENY
+action for the same range will leave the whole range as disabled.
+
+Restrictions: Event 0 (SW_INCR) is never filtered, as it doesn't count a
+hardware event. Filtering event 0x1E (CHAIN) has no effect either, as it
+isn't strictly speaking an event. Filtering the cycle counter is possible
+using event 0x11 (CPU_CYCLES).
+
+
+2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
+=================================
+
+:Architectures: ARM, ARM64
+
+2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_VTIMER, KVM_ARM_VCPU_TIMER_IRQ_PTIMER
+-----------------------------------------------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address for the timer interrupt is a
+ pointer to an int
+
+Returns:
+
+ ======= =================================
+ -EINVAL Invalid timer interrupt number
+ -EBUSY One or more VCPUs has already run
+ ======= =================================
+
+A value describing the architected timer interrupt number when connected to an
+in-kernel virtual GIC. These must be a PPI (16 <= intid < 32). Setting the
+attribute overrides the default values (see below).
+
+============================= ==========================================
+KVM_ARM_VCPU_TIMER_IRQ_VTIMER The EL1 virtual timer intid (default: 27)
+KVM_ARM_VCPU_TIMER_IRQ_PTIMER The EL1 physical timer intid (default: 30)
+============================= ==========================================
+
+Setting the same PPI for different timers will prevent the VCPUs from running.
+Setting the interrupt number on a VCPU configures all VCPUs created at that
+time to use the number provided for a given timer, overwriting any previously
+configured values on other VCPUs. Userspace should configure the interrupt
+numbers on at least one VCPU after creating all VCPUs and before running any
+VCPUs.
+
+3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
+==================================
+
+:Architectures: ARM64
+
+3.1 ATTRIBUTE: KVM_ARM_VCPU_PVTIME_IPA
+--------------------------------------
+
+:Parameters: 64-bit base address
+
+Returns:
+
+ ======= ======================================
+ -ENXIO Stolen time not implemented
+ -EEXIST Base address already set for this VCPU
+ -EINVAL Base address not 64 byte aligned
+ ======= ======================================
+
+Specifies the base address of the stolen time structure for this VCPU. The
+base address must be 64 byte aligned and exist within a valid guest memory
+region. See Documentation/virt/kvm/arm/pvtime.rst for more information
+including the layout of the stolen time structure.
diff --git a/Documentation/virt/kvm/devices/vfio.rst b/Documentation/virt/kvm/devices/vfio.rst
new file mode 100644
index 000000000..2d20dc561
--- /dev/null
+++ b/Documentation/virt/kvm/devices/vfio.rst
@@ -0,0 +1,41 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+VFIO virtual device
+===================
+
+Device types supported:
+
+ - KVM_DEV_TYPE_VFIO
+
+Only one VFIO instance may be created per VM. The created device
+tracks VFIO groups in use by the VM and features of those groups
+important to the correctness and acceleration of the VM. As groups
+are enabled and disabled for use by the VM, KVM should be updated
+about their presence. When registered with KVM, a reference to the
+VFIO-group is held by KVM.
+
+Groups:
+ KVM_DEV_VFIO_GROUP
+
+KVM_DEV_VFIO_GROUP attributes:
+ KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
+ kvm_device_attr.addr points to an int32_t file descriptor
+ for the VFIO group.
+ KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking
+ kvm_device_attr.addr points to an int32_t file descriptor
+ for the VFIO group.
+ KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE: attaches a guest visible TCE table
+ allocated by sPAPR KVM.
+ kvm_device_attr.addr points to a struct::
+
+ struct kvm_vfio_spapr_tce {
+ __s32 groupfd;
+ __s32 tablefd;
+ };
+
+ where:
+
+ - @groupfd is a file descriptor for a VFIO group;
+ - @tablefd is a file descriptor for a TCE table allocated via
+ KVM_CREATE_SPAPR_TCE.
diff --git a/Documentation/virt/kvm/devices/vm.rst b/Documentation/virt/kvm/devices/vm.rst
new file mode 100644
index 000000000..147efec62
--- /dev/null
+++ b/Documentation/virt/kvm/devices/vm.rst
@@ -0,0 +1,323 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+Generic vm interface
+====================
+
+The virtual machine "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
+KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same
+struct kvm_device_attr as other devices, but targets VM-wide settings
+and controls.
+
+The groups and attributes per virtual machine, if any, are architecture
+specific.
+
+1. GROUP: KVM_S390_VM_MEM_CTRL
+==============================
+
+:Architectures: s390
+
+1.1. ATTRIBUTE: KVM_S390_VM_MEM_ENABLE_CMMA
+-------------------------------------------
+
+:Parameters: none
+:Returns: -EBUSY if a vcpu is already defined, otherwise 0
+
+Enables Collaborative Memory Management Assist (CMMA) for the virtual machine.
+
+1.2. ATTRIBUTE: KVM_S390_VM_MEM_CLR_CMMA
+----------------------------------------
+
+:Parameters: none
+:Returns: -EINVAL if CMMA was not enabled;
+ 0 otherwise
+
+Clear the CMMA status for all guest pages, so any pages the guest marked
+as unused are again used any may not be reclaimed by the host.
+
+1.3. ATTRIBUTE KVM_S390_VM_MEM_LIMIT_SIZE
+-----------------------------------------
+
+:Parameters: in attr->addr the address for the new limit of guest memory
+:Returns: -EFAULT if the given address is not accessible;
+ -EINVAL if the virtual machine is of type UCONTROL;
+ -E2BIG if the given guest memory is to big for that machine;
+ -EBUSY if a vcpu is already defined;
+ -ENOMEM if not enough memory is available for a new shadow guest mapping;
+ 0 otherwise.
+
+Allows userspace to query the actual limit and set a new limit for
+the maximum guest memory size. The limit will be rounded up to
+2048 MB, 4096 GB, 8192 TB respectively, as this limit is governed by
+the number of page table levels. In the case that there is no limit we will set
+the limit to KVM_S390_NO_MEM_LIMIT (U64_MAX).
+
+2. GROUP: KVM_S390_VM_CPU_MODEL
+===============================
+
+:Architectures: s390
+
+2.1. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE (r/o)
+---------------------------------------------
+
+Allows user space to retrieve machine and kvm specific cpu related information::
+
+ struct kvm_s390_vm_cpu_machine {
+ __u64 cpuid; # CPUID of host
+ __u32 ibc; # IBC level range offered by host
+ __u8 pad[4];
+ __u64 fac_mask[256]; # set of cpu facilities enabled by KVM
+ __u64 fac_list[256]; # set of cpu facilities offered by host
+ }
+
+:Parameters: address of buffer to store the machine related cpu data
+ of type struct kvm_s390_vm_cpu_machine*
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ -ENOMEM if not enough memory is available to process the ioctl;
+ 0 in case of success.
+
+2.2. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR (r/w)
+===============================================
+
+Allows user space to retrieve or request to change cpu related information for a vcpu::
+
+ struct kvm_s390_vm_cpu_processor {
+ __u64 cpuid; # CPUID currently (to be) used by this vcpu
+ __u16 ibc; # IBC level currently (to be) used by this vcpu
+ __u8 pad[6];
+ __u64 fac_list[256]; # set of cpu facilities currently (to be) used
+ # by this vcpu
+ }
+
+KVM does not enforce or limit the cpu model data in any form. Take the information
+retrieved by means of KVM_S390_VM_CPU_MACHINE as hint for reasonable configuration
+setups. Instruction interceptions triggered by additionally set facility bits that
+are not handled by KVM need to by imlemented in the VM driver code.
+
+:Parameters: address of buffer to store/set the processor related cpu
+ data of type struct kvm_s390_vm_cpu_processor*.
+:Returns: -EBUSY in case 1 or more vcpus are already activated (only in write case);
+ -EFAULT if the given address is not accessible from kernel space;
+ -ENOMEM if not enough memory is available to process the ioctl;
+ 0 in case of success.
+
+.. _KVM_S390_VM_CPU_MACHINE_FEAT:
+
+2.3. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE_FEAT (r/o)
+--------------------------------------------------
+
+Allows user space to retrieve available cpu features. A feature is available if
+provided by the hardware and supported by kvm. In theory, cpu features could
+even be completely emulated by kvm.
+
+::
+
+ struct kvm_s390_vm_cpu_feat {
+ __u64 feat[16]; # Bitmap (1 = feature available), MSB 0 bit numbering
+ };
+
+:Parameters: address of a buffer to load the feature list from.
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ 0 in case of success.
+
+2.4. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR_FEAT (r/w)
+----------------------------------------------------
+
+Allows user space to retrieve or change enabled cpu features for all VCPUs of a
+VM. Features that are not available cannot be enabled.
+
+See :ref:`KVM_S390_VM_CPU_MACHINE_FEAT` for
+a description of the parameter struct.
+
+:Parameters: address of a buffer to store/load the feature list from.
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ -EINVAL if a cpu feature that is not available is to be enabled;
+ -EBUSY if at least one VCPU has already been defined;
+ 0 in case of success.
+
+.. _KVM_S390_VM_CPU_MACHINE_SUBFUNC:
+
+2.5. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE_SUBFUNC (r/o)
+-----------------------------------------------------
+
+Allows user space to retrieve available cpu subfunctions without any filtering
+done by a set IBC. These subfunctions are indicated to the guest VCPU via
+query or "test bit" subfunctions and used e.g. by cpacf functions, plo and ptff.
+
+A subfunction block is only valid if KVM_S390_VM_CPU_MACHINE contains the
+STFL(E) bit introducing the affected instruction. If the affected instruction
+indicates subfunctions via a "query subfunction", the response block is
+contained in the returned struct. If the affected instruction
+indicates subfunctions via a "test bit" mechanism, the subfunction codes are
+contained in the returned struct in MSB 0 bit numbering.
+
+::
+
+ struct kvm_s390_vm_cpu_subfunc {
+ u8 plo[32]; # always valid (ESA/390 feature)
+ u8 ptff[16]; # valid with TOD-clock steering
+ u8 kmac[16]; # valid with Message-Security-Assist
+ u8 kmc[16]; # valid with Message-Security-Assist
+ u8 km[16]; # valid with Message-Security-Assist
+ u8 kimd[16]; # valid with Message-Security-Assist
+ u8 klmd[16]; # valid with Message-Security-Assist
+ u8 pckmo[16]; # valid with Message-Security-Assist-Extension 3
+ u8 kmctr[16]; # valid with Message-Security-Assist-Extension 4
+ u8 kmf[16]; # valid with Message-Security-Assist-Extension 4
+ u8 kmo[16]; # valid with Message-Security-Assist-Extension 4
+ u8 pcc[16]; # valid with Message-Security-Assist-Extension 4
+ u8 ppno[16]; # valid with Message-Security-Assist-Extension 5
+ u8 kma[16]; # valid with Message-Security-Assist-Extension 8
+ u8 kdsa[16]; # valid with Message-Security-Assist-Extension 9
+ u8 reserved[1792]; # reserved for future instructions
+ };
+
+:Parameters: address of a buffer to load the subfunction blocks from.
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ 0 in case of success.
+
+2.6. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR_SUBFUNC (r/w)
+-------------------------------------------------------
+
+Allows user space to retrieve or change cpu subfunctions to be indicated for
+all VCPUs of a VM. This attribute will only be available if kernel and
+hardware support are in place.
+
+The kernel uses the configured subfunction blocks for indication to
+the guest. A subfunction block will only be used if the associated STFL(E) bit
+has not been disabled by user space (so the instruction to be queried is
+actually available for the guest).
+
+As long as no data has been written, a read will fail. The IBC will be used
+to determine available subfunctions in this case, this will guarantee backward
+compatibility.
+
+See :ref:`KVM_S390_VM_CPU_MACHINE_SUBFUNC` for a
+description of the parameter struct.
+
+:Parameters: address of a buffer to store/load the subfunction blocks from.
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ -EINVAL when reading, if there was no write yet;
+ -EBUSY if at least one VCPU has already been defined;
+ 0 in case of success.
+
+3. GROUP: KVM_S390_VM_TOD
+=========================
+
+:Architectures: s390
+
+3.1. ATTRIBUTE: KVM_S390_VM_TOD_HIGH
+------------------------------------
+
+Allows user space to set/get the TOD clock extension (u8) (superseded by
+KVM_S390_VM_TOD_EXT).
+
+:Parameters: address of a buffer in user space to store the data (u8) to
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ -EINVAL if setting the TOD clock extension to != 0 is not supported
+ -EOPNOTSUPP for a PV guest (TOD managed by the ultravisor)
+
+3.2. ATTRIBUTE: KVM_S390_VM_TOD_LOW
+-----------------------------------
+
+Allows user space to set/get bits 0-63 of the TOD clock register as defined in
+the POP (u64).
+
+:Parameters: address of a buffer in user space to store the data (u64) to
+:Returns: -EFAULT if the given address is not accessible from kernel space
+ -EOPNOTSUPP for a PV guest (TOD managed by the ultravisor)
+
+3.3. ATTRIBUTE: KVM_S390_VM_TOD_EXT
+-----------------------------------
+
+Allows user space to set/get bits 0-63 of the TOD clock register as defined in
+the POP (u64). If the guest CPU model supports the TOD clock extension (u8), it
+also allows user space to get/set it. If the guest CPU model does not support
+it, it is stored as 0 and not allowed to be set to a value != 0.
+
+:Parameters: address of a buffer in user space to store the data
+ (kvm_s390_vm_tod_clock) to
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ -EINVAL if setting the TOD clock extension to != 0 is not supported
+ -EOPNOTSUPP for a PV guest (TOD managed by the ultravisor)
+
+4. GROUP: KVM_S390_VM_CRYPTO
+============================
+
+:Architectures: s390
+
+4.1. ATTRIBUTE: KVM_S390_VM_CRYPTO_ENABLE_AES_KW (w/o)
+------------------------------------------------------
+
+Allows user space to enable aes key wrapping, including generating a new
+wrapping key.
+
+:Parameters: none
+:Returns: 0
+
+4.2. ATTRIBUTE: KVM_S390_VM_CRYPTO_ENABLE_DEA_KW (w/o)
+------------------------------------------------------
+
+Allows user space to enable dea key wrapping, including generating a new
+wrapping key.
+
+:Parameters: none
+:Returns: 0
+
+4.3. ATTRIBUTE: KVM_S390_VM_CRYPTO_DISABLE_AES_KW (w/o)
+-------------------------------------------------------
+
+Allows user space to disable aes key wrapping, clearing the wrapping key.
+
+:Parameters: none
+:Returns: 0
+
+4.4. ATTRIBUTE: KVM_S390_VM_CRYPTO_DISABLE_DEA_KW (w/o)
+-------------------------------------------------------
+
+Allows user space to disable dea key wrapping, clearing the wrapping key.
+
+:Parameters: none
+:Returns: 0
+
+5. GROUP: KVM_S390_VM_MIGRATION
+===============================
+
+:Architectures: s390
+
+5.1. ATTRIBUTE: KVM_S390_VM_MIGRATION_STOP (w/o)
+------------------------------------------------
+
+Allows userspace to stop migration mode, needed for PGSTE migration.
+Setting this attribute when migration mode is not active will have no
+effects.
+
+:Parameters: none
+:Returns: 0
+
+5.2. ATTRIBUTE: KVM_S390_VM_MIGRATION_START (w/o)
+-------------------------------------------------
+
+Allows userspace to start migration mode, needed for PGSTE migration.
+Setting this attribute when migration mode is already active will have
+no effects.
+
+Dirty tracking must be enabled on all memslots, else -EINVAL is returned. When
+dirty tracking is disabled on any memslot, migration mode is automatically
+stopped.
+
+:Parameters: none
+:Returns: -ENOMEM if there is not enough free memory to start migration mode;
+ -EINVAL if the state of the VM is invalid (e.g. no memory defined);
+ 0 in case of success.
+
+5.3. ATTRIBUTE: KVM_S390_VM_MIGRATION_STATUS (r/o)
+--------------------------------------------------
+
+Allows userspace to query the status of migration mode.
+
+:Parameters: address of a buffer in user space to store the data (u64) to;
+ the data itself is either 0 if migration mode is disabled or 1
+ if it is enabled
+:Returns: -EFAULT if the given address is not accessible from kernel space;
+ 0 in case of success.
diff --git a/Documentation/virt/kvm/devices/xics.rst b/Documentation/virt/kvm/devices/xics.rst
new file mode 100644
index 000000000..2d6927e0b
--- /dev/null
+++ b/Documentation/virt/kvm/devices/xics.rst
@@ -0,0 +1,92 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+XICS interrupt controller
+=========================
+
+Device type supported: KVM_DEV_TYPE_XICS
+
+Groups:
+ 1. KVM_DEV_XICS_GRP_SOURCES
+ Attributes:
+
+ One per interrupt source, indexed by the source number.
+ 2. KVM_DEV_XICS_GRP_CTRL
+ Attributes:
+
+ 2.1 KVM_DEV_XICS_NR_SERVERS (write only)
+
+ The kvm_device_attr.addr points to a __u32 value which is the number of
+ interrupt server numbers (ie, highest possible vcpu id plus one).
+
+ Errors:
+
+ ======= ==========================================
+ -EINVAL Value greater than KVM_MAX_VCPU_ID.
+ -EFAULT Invalid user pointer for attr->addr.
+ -EBUSY A vcpu is already connected to the device.
+ ======= ==========================================
+
+This device emulates the XICS (eXternal Interrupt Controller
+Specification) defined in PAPR. The XICS has a set of interrupt
+sources, each identified by a 20-bit source number, and a set of
+Interrupt Control Presentation (ICP) entities, also called "servers",
+each associated with a virtual CPU.
+
+The ICP entities are created by enabling the KVM_CAP_IRQ_ARCH
+capability for each vcpu, specifying KVM_CAP_IRQ_XICS in args[0] and
+the interrupt server number (i.e. the vcpu number from the XICS's
+point of view) in args[1] of the kvm_enable_cap struct. Each ICP has
+64 bits of state which can be read and written using the
+KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls on the vcpu. The 64 bit
+state word has the following bitfields, starting at the
+least-significant end of the word:
+
+* Unused, 16 bits
+
+* Pending interrupt priority, 8 bits
+ Zero is the highest priority, 255 means no interrupt is pending.
+
+* Pending IPI (inter-processor interrupt) priority, 8 bits
+ Zero is the highest priority, 255 means no IPI is pending.
+
+* Pending interrupt source number, 24 bits
+ Zero means no interrupt pending, 2 means an IPI is pending
+
+* Current processor priority, 8 bits
+ Zero is the highest priority, meaning no interrupts can be
+ delivered, and 255 is the lowest priority.
+
+Each source has 64 bits of state that can be read and written using
+the KVM_GET_DEVICE_ATTR and KVM_SET_DEVICE_ATTR ioctls, specifying the
+KVM_DEV_XICS_GRP_SOURCES attribute group, with the attribute number being
+the interrupt source number. The 64 bit state word has the following
+bitfields, starting from the least-significant end of the word:
+
+* Destination (server number), 32 bits
+
+ This specifies where the interrupt should be sent, and is the
+ interrupt server number specified for the destination vcpu.
+
+* Priority, 8 bits
+
+ This is the priority specified for this interrupt source, where 0 is
+ the highest priority and 255 is the lowest. An interrupt with a
+ priority of 255 will never be delivered.
+
+* Level sensitive flag, 1 bit
+
+ This bit is 1 for a level-sensitive interrupt source, or 0 for
+ edge-sensitive (or MSI).
+
+* Masked flag, 1 bit
+
+ This bit is set to 1 if the interrupt is masked (cannot be delivered
+ regardless of its priority), for example by the ibm,int-off RTAS
+ call, or 0 if it is not masked.
+
+* Pending flag, 1 bit
+
+ This bit is 1 if the source has a pending interrupt, otherwise 0.
+
+Only one XICS instance may be created per VM.
diff --git a/Documentation/virt/kvm/devices/xive.rst b/Documentation/virt/kvm/devices/xive.rst
new file mode 100644
index 000000000..8bdf3dc38
--- /dev/null
+++ b/Documentation/virt/kvm/devices/xive.rst
@@ -0,0 +1,247 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===========================================================
+POWER9 eXternal Interrupt Virtualization Engine (XIVE Gen1)
+===========================================================
+
+Device types supported:
+ - KVM_DEV_TYPE_XIVE POWER9 XIVE Interrupt Controller generation 1
+
+This device acts as a VM interrupt controller. It provides the KVM
+interface to configure the interrupt sources of a VM in the underlying
+POWER9 XIVE interrupt controller.
+
+Only one XIVE instance may be instantiated. A guest XIVE device
+requires a POWER9 host and the guest OS should have support for the
+XIVE native exploitation interrupt mode. If not, it should run using
+the legacy interrupt mode, referred as XICS (POWER7/8).
+
+* Device Mappings
+
+ The KVM device exposes different MMIO ranges of the XIVE HW which
+ are required for interrupt management. These are exposed to the
+ guest in VMAs populated with a custom VM fault handler.
+
+ 1. Thread Interrupt Management Area (TIMA)
+
+ Each thread has an associated Thread Interrupt Management context
+ composed of a set of registers. These registers let the thread
+ handle priority management and interrupt acknowledgment. The most
+ important are :
+
+ - Interrupt Pending Buffer (IPB)
+ - Current Processor Priority (CPPR)
+ - Notification Source Register (NSR)
+
+ They are exposed to software in four different pages each proposing
+ a view with a different privilege. The first page is for the
+ physical thread context and the second for the hypervisor. Only the
+ third (operating system) and the fourth (user level) are exposed the
+ guest.
+
+ 2. Event State Buffer (ESB)
+
+ Each source is associated with an Event State Buffer (ESB) with
+ either a pair of even/odd pair of pages which provides commands to
+ manage the source: to trigger, to EOI, to turn off the source for
+ instance.
+
+ 3. Device pass-through
+
+ When a device is passed-through into the guest, the source
+ interrupts are from a different HW controller (PHB4) and the ESB
+ pages exposed to the guest should accommadate this change.
+
+ The passthru_irq helpers, kvmppc_xive_set_mapped() and
+ kvmppc_xive_clr_mapped() are called when the device HW irqs are
+ mapped into or unmapped from the guest IRQ number space. The KVM
+ device extends these helpers to clear the ESB pages of the guest IRQ
+ number being mapped and then lets the VM fault handler repopulate.
+ The handler will insert the ESB page corresponding to the HW
+ interrupt of the device being passed-through or the initial IPI ESB
+ page if the device has being removed.
+
+ The ESB remapping is fully transparent to the guest and the OS
+ device driver. All handling is done within VFIO and the above
+ helpers in KVM-PPC.
+
+* Groups:
+
+1. KVM_DEV_XIVE_GRP_CTRL
+ Provides global controls on the device
+
+ Attributes:
+ 1.1 KVM_DEV_XIVE_RESET (write only)
+ Resets the interrupt controller configuration for sources and event
+ queues. To be used by kexec and kdump.
+
+ Errors: none
+
+ 1.2 KVM_DEV_XIVE_EQ_SYNC (write only)
+ Sync all the sources and queues and mark the EQ pages dirty. This
+ to make sure that a consistent memory state is captured when
+ migrating the VM.
+
+ Errors: none
+
+ 1.3 KVM_DEV_XIVE_NR_SERVERS (write only)
+ The kvm_device_attr.addr points to a __u32 value which is the number of
+ interrupt server numbers (ie, highest possible vcpu id plus one).
+
+ Errors:
+
+ ======= ==========================================
+ -EINVAL Value greater than KVM_MAX_VCPU_ID.
+ -EFAULT Invalid user pointer for attr->addr.
+ -EBUSY A vCPU is already connected to the device.
+ ======= ==========================================
+
+2. KVM_DEV_XIVE_GRP_SOURCE (write only)
+ Initializes a new source in the XIVE device and mask it.
+
+ Attributes:
+ Interrupt source number (64-bit)
+
+ The kvm_device_attr.addr points to a __u64 value::
+
+ bits: | 63 .... 2 | 1 | 0
+ values: | unused | level | type
+
+ - type: 0:MSI 1:LSI
+ - level: assertion level in case of an LSI.
+
+ Errors:
+
+ ======= ==========================================
+ -E2BIG Interrupt source number is out of range
+ -ENOMEM Could not create a new source block
+ -EFAULT Invalid user pointer for attr->addr.
+ -ENXIO Could not allocate underlying HW interrupt
+ ======= ==========================================
+
+3. KVM_DEV_XIVE_GRP_SOURCE_CONFIG (write only)
+ Configures source targeting
+
+ Attributes:
+ Interrupt source number (64-bit)
+
+ The kvm_device_attr.addr points to a __u64 value::
+
+ bits: | 63 .... 33 | 32 | 31 .. 3 | 2 .. 0
+ values: | eisn | mask | server | priority
+
+ - priority: 0-7 interrupt priority level
+ - server: CPU number chosen to handle the interrupt
+ - mask: mask flag (unused)
+ - eisn: Effective Interrupt Source Number
+
+ Errors:
+
+ ======= =======================================================
+ -ENOENT Unknown source number
+ -EINVAL Not initialized source number
+ -EINVAL Invalid priority
+ -EINVAL Invalid CPU number.
+ -EFAULT Invalid user pointer for attr->addr.
+ -ENXIO CPU event queues not configured or configuration of the
+ underlying HW interrupt failed
+ -EBUSY No CPU available to serve interrupt
+ ======= =======================================================
+
+4. KVM_DEV_XIVE_GRP_EQ_CONFIG (read-write)
+ Configures an event queue of a CPU
+
+ Attributes:
+ EQ descriptor identifier (64-bit)
+
+ The EQ descriptor identifier is a tuple (server, priority)::
+
+ bits: | 63 .... 32 | 31 .. 3 | 2 .. 0
+ values: | unused | server | priority
+
+ The kvm_device_attr.addr points to::
+
+ struct kvm_ppc_xive_eq {
+ __u32 flags;
+ __u32 qshift;
+ __u64 qaddr;
+ __u32 qtoggle;
+ __u32 qindex;
+ __u8 pad[40];
+ };
+
+ - flags: queue flags
+ KVM_XIVE_EQ_ALWAYS_NOTIFY (required)
+ forces notification without using the coalescing mechanism
+ provided by the XIVE END ESBs.
+ - qshift: queue size (power of 2)
+ - qaddr: real address of queue
+ - qtoggle: current queue toggle bit
+ - qindex: current queue index
+ - pad: reserved for future use
+
+ Errors:
+
+ ======= =========================================
+ -ENOENT Invalid CPU number
+ -EINVAL Invalid priority
+ -EINVAL Invalid flags
+ -EINVAL Invalid queue size
+ -EINVAL Invalid queue address
+ -EFAULT Invalid user pointer for attr->addr.
+ -EIO Configuration of the underlying HW failed
+ ======= =========================================
+
+5. KVM_DEV_XIVE_GRP_SOURCE_SYNC (write only)
+ Synchronize the source to flush event notifications
+
+ Attributes:
+ Interrupt source number (64-bit)
+
+ Errors:
+
+ ======= =============================
+ -ENOENT Unknown source number
+ -EINVAL Not initialized source number
+ ======= =============================
+
+* VCPU state
+
+ The XIVE IC maintains VP interrupt state in an internal structure
+ called the NVT. When a VP is not dispatched on a HW processor
+ thread, this structure can be updated by HW if the VP is the target
+ of an event notification.
+
+ It is important for migration to capture the cached IPB from the NVT
+ as it synthesizes the priorities of the pending interrupts. We
+ capture a bit more to report debug information.
+
+ KVM_REG_PPC_VP_STATE (2 * 64bits)::
+
+ bits: | 63 .... 32 | 31 .... 0 |
+ values: | TIMA word0 | TIMA word1 |
+ bits: | 127 .......... 64 |
+ values: | unused |
+
+* Migration:
+
+ Saving the state of a VM using the XIVE native exploitation mode
+ should follow a specific sequence. When the VM is stopped :
+
+ 1. Mask all sources (PQ=01) to stop the flow of events.
+
+ 2. Sync the XIVE device with the KVM control KVM_DEV_XIVE_EQ_SYNC to
+ flush any in-flight event notification and to stabilize the EQs. At
+ this stage, the EQ pages are marked dirty to make sure they are
+ transferred in the migration sequence.
+
+ 3. Capture the state of the source targeting, the EQs configuration
+ and the state of thread interrupt context registers.
+
+ Restore is similar:
+
+ 1. Restore the EQ configuration. As targeting depends on it.
+ 2. Restore targeting
+ 3. Restore the thread interrupt contexts
+ 4. Restore the source states
+ 5. Let the vCPU run