Merge tag 'kvm-arm-for-v4.12-round2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

Second round of KVM/ARM Changes for v4.12.

Changes include:
 - A fix related to the 32-bit idmap stub
 - A fix to the bitmask used to deode the operands of an AArch32 CP
   instruction
 - We have moved the files shared between arch/arm/kvm and
   arch/arm64/kvm to virt/kvm/arm
 - We add support for saving/restoring the virtual ITS state to
   userspace

Author: bonzini

Documentation/virtual/kvm/devices/arm-vgic-its.txt

@@ -32,7 +32,128 @@ Groups:
     KVM_DEV_ARM_VGIC_CTRL_INIT
       request the initialization of the ITS, no additional parameter in
       kvm_device_attr.addr.
+
+    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
+
+  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

Documentation/virtual/kvm/devices/arm-vgic-v3.txt

@@ -167,11 +167,17 @@ Groups:
     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

arch/arm/include/uapi/asm/kvm.h

@@ -196,13 +196,17 @@ struct kvm_arch_memory_slot {
 #define KVM_DEV_ARM_VGIC_GRP_REDIST_REGS 5
 #define KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS 6
 #define KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO  7
+#define KVM_DEV_ARM_VGIC_GRP_ITS_REGS	8
 #define KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT	10
 #define KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_MASK \
 			(0x3fffffULL << KVM_DEV_ARM_VGIC_LINE_LEVEL_INFO_SHIFT)
 #define KVM_DEV_ARM_VGIC_LINE_LEVEL_INTID_MASK 0x3ff
 #define VGIC_LEVEL_INFO_LINE_LEVEL	0
 
-#define   KVM_DEV_ARM_VGIC_CTRL_INIT    0
+#define   KVM_DEV_ARM_VGIC_CTRL_INIT		0
+#define   KVM_DEV_ARM_ITS_SAVE_TABLES		1
+#define   KVM_DEV_ARM_ITS_RESTORE_TABLES	2
+#define   KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES	3
 
 /* KVM_IRQ_LINE irq field index values */
 #define KVM_ARM_IRQ_TYPE_SHIFT		24

arch/arm/kvm/Makefile

@@ -18,9 +18,12 @@ KVM := ../../../virt/kvm
 kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o
 
 obj-$(CONFIG_KVM_ARM_HOST) += hyp/
+
 obj-y += kvm-arm.o init.o interrupts.o
-obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o
-obj-y += coproc.o coproc_a15.o coproc_a7.o mmio.o psci.o perf.o vgic-v3-coproc.o
+obj-y += handle_exit.o guest.o emulate.o reset.o
+obj-y += coproc.o coproc_a15.o coproc_a7.o   vgic-v3-coproc.o
+obj-y += $(KVM)/arm/arm.o $(KVM)/arm/mmu.o $(KVM)/arm/mmio.o
+obj-y += $(KVM)/arm/psci.o $(KVM)/arm/perf.o
 obj-y += $(KVM)/arm/aarch32.o
 
 obj-y += $(KVM)/arm/vgic/vgic.o