Merge tag 'v5.9-rc7' into patchwork

Linux 5.9-rc7

* tag 'v5.9-rc7': (683 commits)
  Linux 5.9-rc7
  mm/thp: Split huge pmds/puds if they're pinned when fork()
  mm: Do early cow for pinned pages during fork() for ptes
  mm/fork: Pass new vma pointer into copy_page_range()
  mm: Introduce mm_struct.has_pinned
  mm: validate pmd after splitting
  mm: don't rely on system state to detect hot-plug operations
  mm: replace memmap_context by meminit_context
  arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback
  lib/memregion.c: include memregion.h
  lib/string.c: implement stpcpy
  mm/migrate: correct thp migration stats
  mm/gup: fix gup_fast with dynamic page table folding
  mm: memcontrol: fix missing suffix of workingset_restore
  mm, THP, swap: fix allocating cluster for swapfile by mistake
  mm: slab: fix potential double free in ___cache_free
  Documentation/llvm: Fix clang target examples
  io_uring: ensure async buffered read-retry is setup properly
  KVM: SVM: Add a dedicated INVD intercept routine
  io_uring: don't unconditionally set plug->nowait = true
  ...

15 files changed, 160 insertions, 99 deletions

diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 6be43781ec7f..baa07b30845e 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1324,15 +1324,26 @@ PAGE_SIZE multiple when read back.
 	  pgmajfault
 		Number of major page faults incurred
 
-	  workingset_refault
-		Number of refaults of previously evicted pages
+	  workingset_refault_anon
+		Number of refaults of previously evicted anonymous pages.
 
-	  workingset_activate
-		Number of refaulted pages that were immediately activated
+	  workingset_refault_file
+		Number of refaults of previously evicted file pages.
 
-	  workingset_restore
-		Number of restored pages which have been detected as an active
-		workingset before they got reclaimed.
+	  workingset_activate_anon
+		Number of refaulted anonymous pages that were immediately
+		activated.
+
+	  workingset_activate_file
+		Number of refaulted file pages that were immediately activated.
+
+	  workingset_restore_anon
+		Number of restored anonymous pages which have been detected as
+		an active workingset before they got reclaimed.
+
+	  workingset_restore_file
+		Number of restored file pages which have been detected as an
+		active workingset before they got reclaimed.
 
 	  workingset_nodereclaim
 		Number of times a shadow node has been reclaimed
diff --git a/Documentation/admin-guide/device-mapper/dm-crypt.rst b/Documentation/admin-guide/device-mapper/dm-crypt.rst
index 8f4a3f889d43..bc28a9527ee5 100644
--- a/Documentation/admin-guide/device-mapper/dm-crypt.rst
+++ b/Documentation/admin-guide/device-mapper/dm-crypt.rst
@@ -67,7 +67,7 @@ Parameters::
     the value passed in <key_size>.
 
 <key_type>
-    Either 'logon' or 'user' kernel key type.
+    Either 'logon', 'user' or 'encrypted' kernel key type.
 
 <key_description>
     The kernel keyring key description crypt target should look for
@@ -121,6 +121,14 @@ submit_from_crypt_cpus
     thread because it benefits CFQ to have writes submitted using the
     same context.
 
+no_read_workqueue
+    Bypass dm-crypt internal workqueue and process read requests synchronously.
+
+no_write_workqueue
+    Bypass dm-crypt internal workqueue and process write requests synchronously.
+    This option is automatically enabled for host-managed zoned block devices
+    (e.g. host-managed SMR hard-disks).
+
 integrity:<bytes>:<type>
     The device requires additional <bytes> metadata per-sector stored
     in per-bio integrity structure. This metadata must by provided
diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst
index e5a8def45f3f..6c04aea8f4cd 100644
--- a/Documentation/admin-guide/dynamic-debug-howto.rst
+++ b/Documentation/admin-guide/dynamic-debug-howto.rst
@@ -156,7 +156,6 @@ against.  Possible keywords are:::
   ``line-range`` cannot contain space, e.g.
   "1-30" is valid range but "1 - 30" is not.
 
-  ``module=foo`` combined keyword=value form is interchangably accepted
 
 The meanings of each keyword are:
 
diff --git a/Documentation/bpf/ringbuf.rst b/Documentation/bpf/ringbuf.rst
index 75f943f0009d..6a615cd62bda 100644
--- a/Documentation/bpf/ringbuf.rst
+++ b/Documentation/bpf/ringbuf.rst
@@ -182,9 +182,6 @@ in the order of reservations, but only after all previous records where
 already committed. It is thus possible for slow producers to temporarily hold
 off submitted records, that were reserved later.
 
-Reservation/commit/consumer protocol is verified by litmus tests in
-Documentation/litmus_tests/bpf-rb/_.
-
 One interesting implementation bit, that significantly simplifies (and thus
 speeds up as well) implementation of both producers and consumers is how data
 area is mapped twice contiguously back-to-back in the virtual memory. This
@@ -200,7 +197,7 @@ a self-pacing notifications of new data being availability.
 being available after commit only if consumer has already caught up right up to
 the record being committed. If not, consumer still has to catch up and thus
 will see new data anyways without needing an extra poll notification.
-Benchmarks (see tools/testing/selftests/bpf/benchs/bench_ringbuf.c_) show that
+Benchmarks (see tools/testing/selftests/bpf/benchs/bench_ringbufs.c) show that
 this allows to achieve a very high throughput without having to resort to
 tricks like "notify only every Nth sample", which are necessary with perf
 buffer. For extreme cases, when BPF program wants more manual control of
diff --git a/Documentation/devicetree/bindings/media/i2c/imx274.txt b/Documentation/devicetree/bindings/media/i2c/imx274.txt
deleted file mode 100644
index 0727079d2410..000000000000
--- a/Documentation/devicetree/bindings/media/i2c/imx274.txt
+++ /dev/null
@@ -1,38 +0,0 @@
-* Sony 1/2.5-Inch 8.51Mp CMOS Digital Image Sensor
-
-The Sony imx274 is a 1/2.5-inch CMOS active pixel digital image sensor with
-an active array size of 3864H x 2202V. It is programmable through I2C
-interface. The I2C address is fixed to 0x1a as per sensor data sheet.
-Image data is sent through MIPI CSI-2, which is configured as 4 lanes
-at 1440 Mbps.
-
-
-Required Properties:
-- compatible: value should be "sony,imx274" for imx274 sensor
-- reg: I2C bus address of the device
-
-Optional Properties:
-- reset-gpios: Sensor reset GPIO
-- clocks: Reference to the input clock.
-- clock-names: Should be "inck".
-- VANA-supply: Sensor 2.8v analog supply.
-- VDIG-supply: Sensor 1.8v digital core supply.
-- VDDL-supply: Sensor digital IO 1.2v supply.
-
-The imx274 device node should contain one 'port' child node with
-an 'endpoint' subnode. For further reading on port node refer to
-Documentation/devicetree/bindings/media/video-interfaces.txt.
-
-Example:
-	sensor@1a {
-		compatible = "sony,imx274";
-		reg = <0x1a>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-		reset-gpios = <&gpio_sensor 0 0>;
-		port {
-			sensor_out: endpoint {
-				remote-endpoint = <&csiss_in>;
-			};
-		};
-	};
diff --git a/Documentation/devicetree/bindings/media/i2c/sony,imx274.yaml b/Documentation/devicetree/bindings/media/i2c/sony,imx274.yaml
new file mode 100644
index 000000000000..f697e1a20beb
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/sony,imx274.yaml
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/media/i2c/sony,imx274.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sony 1/2.5-Inch 8.51MP CMOS Digital Image Sensor
+
+maintainers:
+  - Leon Luo <leonl@leopardimaging.com>
+
+description: |
+  The Sony IMX274 is a 1/2.5-inch CMOS active pixel digital image sensor with an
+  active array size of 3864H x 2202V. It is programmable through I2C interface.
+  Image data is sent through MIPI CSI-2, which is configured as 4 lanes at 1440
+  Mbps.
+
+properties:
+  compatible:
+    const: sony,imx274
+
+  reg:
+    const: 0x1a
+
+  reset-gpios:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: inck
+
+  vana-supply:
+    description: Sensor 2.8 V analog supply.
+    maxItems: 1
+
+  vdig-supply:
+    description: Sensor 1.8 V digital core supply.
+    maxItems: 1
+
+  vddl-supply:
+    description: Sensor digital IO 1.2 V supply.
+    maxItems: 1
+
+  port:
+    type: object
+    description: Output video port. See ../video-interfaces.txt.
+
+required:
+  - compatible
+  - reg
+  - port
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c0 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        imx274: camera-sensor@1a {
+            compatible = "sony,imx274";
+            reg = <0x1a>;
+            reset-gpios = <&gpio_sensor 0 0>;
+
+            port {
+                sensor_out: endpoint {
+                    remote-endpoint = <&csiss_in>;
+                };
+            };
+        };
+    };
+
+...
diff --git a/Documentation/devicetree/bindings/spi/brcm,spi-bcm-qspi.txt b/Documentation/devicetree/bindings/spi/brcm,spi-bcm-qspi.txt
index f5e518d099f2..62d4ed2d7fd7 100644
--- a/Documentation/devicetree/bindings/spi/brcm,spi-bcm-qspi.txt
+++ b/Documentation/devicetree/bindings/spi/brcm,spi-bcm-qspi.txt
@@ -23,8 +23,8 @@ Required properties:
 
 - compatible:
     Must be one of :
-    "brcm,spi-bcm-qspi", "brcm,spi-brcmstb-qspi" : MSPI+BSPI on BRCMSTB SoCs
-    "brcm,spi-bcm-qspi", "brcm,spi-brcmstb-mspi" : Second Instance of MSPI
+    "brcm,spi-brcmstb-qspi", "brcm,spi-bcm-qspi" : MSPI+BSPI on BRCMSTB SoCs
+    "brcm,spi-brcmstb-mspi", "brcm,spi-bcm-qspi" : Second Instance of MSPI
 						   BRCMSTB  SoCs
     "brcm,spi-bcm7425-qspi", "brcm,spi-bcm-qspi", "brcm,spi-brcmstb-mspi" : Second Instance of MSPI
     			     			  			    BRCMSTB  SoCs
@@ -36,8 +36,8 @@ Required properties:
     			     			  			    BRCMSTB  SoCs
     "brcm,spi-bcm7278-qspi", "brcm,spi-bcm-qspi", "brcm,spi-brcmstb-mspi" : Second Instance of MSPI
     			     			  			    BRCMSTB  SoCs
-    "brcm,spi-bcm-qspi", "brcm,spi-nsp-qspi"     : MSPI+BSPI on Cygnus, NSP
-    "brcm,spi-bcm-qspi", "brcm,spi-ns2-qspi"     : NS2 SoCs
+    "brcm,spi-nsp-qspi", "brcm,spi-bcm-qspi"     : MSPI+BSPI on Cygnus, NSP
+    "brcm,spi-ns2-qspi", "brcm,spi-bcm-qspi"     : NS2 SoCs
 
 - reg:
     Define the bases and ranges of the associated I/O address spaces.
@@ -86,7 +86,7 @@ BRCMSTB SoC Example:
     spi@f03e3400 {
 		#address-cells = <0x1>;
 		#size-cells = <0x0>;
-		compatible = "brcm,spi-brcmstb-qspi", "brcm,spi-brcmstb-qspi";
+		compatible = "brcm,spi-brcmstb-qspi", "brcm,spi-bcm-qspi";
 		reg = <0xf03e0920 0x4 0xf03e3400 0x188 0xf03e3200 0x50>;
 		reg-names = "cs_reg", "mspi", "bspi";
 		interrupts = <0x6 0x5 0x4 0x3 0x2 0x1 0x0>;
@@ -149,7 +149,7 @@ BRCMSTB SoC Example:
 		#address-cells = <1>;
 		#size-cells = <0>;
 		clocks = <&upg_fixed>;
-		compatible = "brcm,spi-brcmstb-qspi", "brcm,spi-brcmstb-mspi";
+		compatible = "brcm,spi-brcmstb-mspi", "brcm,spi-bcm-qspi";
 		reg = <0xf0416000 0x180>;
 		reg-names = "mspi";
 		interrupts = <0x14>;
@@ -160,7 +160,7 @@ BRCMSTB SoC Example:
 iProc SoC Example:
 
     qspi: spi@18027200 {
-	compatible = "brcm,spi-bcm-qspi", "brcm,spi-nsp-qspi";
+	compatible = "brcm,spi-nsp-qspi", "brcm,spi-bcm-qspi";
 	reg = <0x18027200 0x184>,
 	      <0x18027000 0x124>,
 	      <0x1811c408 0x004>,
@@ -191,7 +191,7 @@ iProc SoC Example:
  NS2 SoC Example:
 
 	       qspi: spi@66470200 {
-		       compatible = "brcm,spi-bcm-qspi", "brcm,spi-ns2-qspi";
+		       compatible = "brcm,spi-ns2-qspi", "brcm,spi-bcm-qspi";
 		       reg = <0x66470200 0x184>,
 			     <0x66470000 0x124>,
 			     <0x67017408 0x004>,
diff --git a/Documentation/driver-api/dma-buf.rst b/Documentation/driver-api/dma-buf.rst
index 100bfd227265..13ea0cc0a3fa 100644
--- a/Documentation/driver-api/dma-buf.rst
+++ b/Documentation/driver-api/dma-buf.rst
@@ -179,7 +179,7 @@ DMA Fence uABI/Sync File
    :internal:
 
 Indefinite DMA Fences
-~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~
 
 At various times &dma_fence with an indefinite time until dma_fence_wait()
 finishes have been proposed. Examples include:
diff --git a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt
index 53da483c8326..1c49723e7534 100644
--- a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt
+++ b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt
@@ -22,7 +22,7 @@
     |       nios2: | TODO |
     |    openrisc: | TODO |
     |      parisc: | TODO |
-    |     powerpc: |  ok  |
+    |     powerpc: | TODO |
     |       riscv: |  ok  |
     |        s390: |  ok  |
     |          sh: | TODO |
diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst
index 334df758dce3..dae90c21aed3 100644
--- a/Documentation/kbuild/llvm.rst
+++ b/Documentation/kbuild/llvm.rst
@@ -39,10 +39,10 @@ which can help simplify cross compiling. ::
 	ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang
 
 ``CROSS_COMPILE`` is not used to prefix the Clang compiler binary, instead
-``CROSS_COMPILE`` is used to set a command line flag: ``--target <triple>``. For
+``CROSS_COMPILE`` is used to set a command line flag: ``--target=<triple>``. For
 example: ::
 
-	clang --target aarch64-linux-gnu foo.c
+	clang --target=aarch64-linux-gnu foo.c
 
 LLVM Utilities
 --------------
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index d53bcb31645a..b5a79881551f 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -206,6 +206,7 @@ Userspace to kernel:
   ``ETHTOOL_MSG_TSINFO_GET``		get timestamping info
   ``ETHTOOL_MSG_CABLE_TEST_ACT``        action start cable test
   ``ETHTOOL_MSG_CABLE_TEST_TDR_ACT``    action start raw TDR cable test
+  ``ETHTOOL_MSG_TUNNEL_INFO_GET``       get tunnel offload info
   ===================================== ================================
 
 Kernel to userspace:
@@ -239,6 +240,7 @@ Kernel to userspace:
   ``ETHTOOL_MSG_TSINFO_GET_REPLY``	timestamping info
   ``ETHTOOL_MSG_CABLE_TEST_NTF``        Cable test results
   ``ETHTOOL_MSG_CABLE_TEST_TDR_NTF``    Cable test TDR results
+  ``ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY`` tunnel offload info
   ===================================== =================================
 
 ``GET`` requests are sent by userspace applications to retrieve device
@@ -1363,4 +1365,5 @@ are netlink only.
   ``ETHTOOL_SFECPARAM``               n/a
   n/a                                 ''ETHTOOL_MSG_CABLE_TEST_ACT''
   n/a                                 ''ETHTOOL_MSG_CABLE_TEST_TDR_ACT''
+  n/a                                 ``ETHTOOL_MSG_TUNNEL_INFO_GET``
   =================================== =====================================
diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst
index 177ed8b6ce62..4f95496adc5b 100644
--- a/Documentation/userspace-api/media/v4l/buffer.rst
+++ b/Documentation/userspace-api/media/v4l/buffer.rst
@@ -694,23 +694,6 @@ Memory Consistency Flags
     :stub-columns: 0
     :widths:       3 1 4
 
-    * .. _`V4L2-FLAG-MEMORY-NON-CONSISTENT`:
-
-      - ``V4L2_FLAG_MEMORY_NON_CONSISTENT``
-      - 0x00000001
-      - A buffer is allocated either in consistent (it will be automatically
-	coherent between the CPU and the bus) or non-consistent memory. The
-	latter can provide performance gains, for instance the CPU cache
-	sync/flush operations can be avoided if the buffer is accessed by the
-	corresponding device only and the CPU does not read/write to/from that
-	buffer. However, this requires extra care from the driver -- it must
-	guarantee memory consistency by issuing a cache flush/sync when
-	consistency is needed. If this flag is set V4L2 will attempt to
-	allocate the buffer in non-consistent memory. The flag takes effect
-	only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the
-	queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS
-	<V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability.
-
 .. c:type:: v4l2_memory
 
 enum v4l2_memory
diff --git a/Documentation/userspace-api/media/v4l/vidioc-create-bufs.rst b/Documentation/userspace-api/media/v4l/vidioc-create-bufs.rst
index c050dffa4237..d999028f47df 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-create-bufs.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-create-bufs.rst
@@ -113,13 +113,9 @@ than the number requested.
 	If you want to just query the capabilities without making any
 	other changes, then set ``count`` to 0, ``memory`` to
 	``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type.
-    * - __u32
-      - ``flags``
-      - Specifies additional buffer management attributes.
-	See :ref:`memory-flags`.
 
     * - __u32
-      - ``reserved``\ [6]
+      - ``reserved``\ [7]
       - A place holder for future extensions. Drivers and applications
 	must set the array to zero.
 
diff --git a/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst b/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst
index 47e433161690..afc35cd7b614 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst
@@ -105,17 +105,10 @@ aborting or finishing any DMA in progress, an implicit
 	``V4L2_MEMORY_MMAP`` and ``type`` set to the buffer type. This will
 	free any previously allocated buffers, so this is typically something
 	that will be done at the start of the application.
-    * - union {
-      - (anonymous)
-    * - __u32
-      - ``flags``
-      - Specifies additional buffer management attributes.
-	See :ref:`memory-flags`.
     * - __u32
       - ``reserved``\ [1]
-      - Kept for backwards compatibility. Use ``flags`` instead.
-    * - }
-      -
+      - A place holder for future extensions. Drivers and applications
+	must set the array to zero.
 
 .. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}|
 
@@ -162,7 +155,6 @@ aborting or finishing any DMA in progress, an implicit
       - This capability is set by the driver to indicate that the queue supports
         cache and memory management hints. However, it's only valid when the
         queue is used for :ref:`memory mapping <mmap>` streaming I/O. See
-        :ref:`V4L2_FLAG_MEMORY_NON_CONSISTENT <V4L2-FLAG-MEMORY-NON-CONSISTENT>`,
         :ref:`V4L2_BUF_FLAG_NO_CACHE_INVALIDATE <V4L2-BUF-FLAG-NO-CACHE-INVALIDATE>` and
         :ref:`V4L2_BUF_FLAG_NO_CACHE_CLEAN <V4L2-BUF-FLAG-NO-CACHE-CLEAN>`.
 
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index eb3a1316f03e..51191b56e61c 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -6130,7 +6130,7 @@ HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx.
 8.21 KVM_CAP_HYPERV_DIRECT_TLBFLUSH
 -----------------------------------
 
-:Architecture: x86
+:Architectures: x86
 
 This capability indicates that KVM running on top of Hyper-V hypervisor
 enables Direct TLB flush for its guests meaning that TLB flush
@@ -6143,19 +6143,53 @@ in CPUID and only exposes Hyper-V identification. In this case, guest
 thinks it's running on Hyper-V and only use Hyper-V hypercalls.
 
 8.22 KVM_CAP_S390_VCPU_RESETS
+-----------------------------
 
-Architectures: s390
+:Architectures: s390
 
 This capability indicates that the KVM_S390_NORMAL_RESET and
 KVM_S390_CLEAR_RESET ioctls are available.
 
 8.23 KVM_CAP_S390_PROTECTED
+---------------------------
 
-Architecture: s390
-
+:Architectures: s390
 
 This capability indicates that the Ultravisor has been initialized and
 KVM can therefore start protected VMs.
 This capability governs the KVM_S390_PV_COMMAND ioctl and the
 KVM_MP_STATE_LOAD MP_STATE. KVM_SET_MP_STATE can fail for protected
 guests when the state change is invalid.
+
+8.24 KVM_CAP_STEAL_TIME
+-----------------------
+
+:Architectures: arm64, x86
+
+This capability indicates that KVM supports steal time accounting.
+When steal time accounting is supported it may be enabled with
+architecture-specific interfaces.  This capability and the architecture-
+specific interfaces must be consistent, i.e. if one says the feature
+is supported, than the other should as well and vice versa.  For arm64
+see Documentation/virt/kvm/devices/vcpu.rst "KVM_ARM_VCPU_PVTIME_CTRL".
+For x86 see Documentation/virt/kvm/msr.rst "MSR_KVM_STEAL_TIME".
+
+8.25 KVM_CAP_S390_DIAG318
+-------------------------
+
+:Architectures: s390
+
+This capability enables a guest to set information about its control program
+(i.e. guest kernel type and version). The information is helpful during
+system/firmware service events, providing additional data about the guest
+environments running on the machine.
+
+The information is associated with the DIAGNOSE 0x318 instruction, which sets
+an 8-byte value consisting of a one-byte Control Program Name Code (CPNC) and
+a 7-byte Control Program Version Code (CPVC). The CPNC determines what
+environment the control program is running in (e.g. Linux, z/VM...), and the
+CPVC is used for information specific to OS (e.g. Linux version, Linux
+distribution...)
+
+If this capability is available, then the CPNC and CPVC can be synchronized
+between KVM and userspace via the sync regs mechanism (KVM_SYNC_DIAG318).