Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "ARM:
   - Improved guest IPA space support (32 to 52 bits)

   - RAS event delivery for 32bit

   - PMU fixes

   - Guest entry hardening

   - Various cleanups

   - Port of dirty_log_test selftest

  PPC:
   - Nested HV KVM support for radix guests on POWER9. The performance
     is much better than with PR KVM. Migration and arbitrary level of
     nesting is supported.

   - Disable nested HV-KVM on early POWER9 chips that need a particular
     hardware bug workaround

   - One VM per core mode to prevent potential data leaks

   - PCI pass-through optimization

   - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base

  s390:
   - Initial version of AP crypto virtualization via vfio-mdev

   - Improvement for vfio-ap

   - Set the host program identifier

   - Optimize page table locking

  x86:
   - Enable nested virtualization by default

   - Implement Hyper-V IPI hypercalls

   - Improve #PF and #DB handling

   - Allow guests to use Enlightened VMCS

   - Add migration selftests for VMCS and Enlightened VMCS

   - Allow coalesced PIO accesses

   - Add an option to perform nested VMCS host state consistency check
     through hardware

   - Automatic tuning of lapic_timer_advance_ns

   - Many fixes, minor improvements, and cleanups"

* tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned
  Revert "kvm: x86: optimize dr6 restore"
  KVM: PPC: Optimize clearing TCEs for sparse tables
  x86/kvm/nVMX: tweak shadow fields
  selftests/kvm: add missing executables to .gitignore
  KVM: arm64: Safety check PSTATE when entering guest and handle IL
  KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips
  arm/arm64: KVM: Enable 32 bits kvm vcpu events support
  arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension()
  KVM: arm64: Fix caching of host MDCR_EL2 value
  KVM: VMX: enable nested virtualization by default
  KVM/x86: Use 32bit xor to clear registers in svm.c
  kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD
  kvm: vmx: Defer setting of DR6 until #DB delivery
  kvm: x86: Defer setting of CR2 until #PF delivery
  kvm: x86: Add payload operands to kvm_multiple_exception
  kvm: x86: Add exception payload fields to kvm_vcpu_events
  kvm: x86: Add has_payload and payload to kvm_queued_exception
  KVM: Documentation: Fix omission in struct kvm_vcpu_events
  KVM: selftests: add Enlightened VMCS test
  ...

1 files changed, 125 insertions, 30 deletions

diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index b476bc46f0ab..6f602af5263c 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -107,6 +107,7 @@
 #define VTCR_EL2_RES1		(1 << 31)
 #define VTCR_EL2_HD		(1 << 22)
 #define VTCR_EL2_HA		(1 << 21)
+#define VTCR_EL2_PS_SHIFT	TCR_EL2_PS_SHIFT
 #define VTCR_EL2_PS_MASK	TCR_EL2_PS_MASK
 #define VTCR_EL2_TG0_MASK	TCR_TG0_MASK
 #define VTCR_EL2_TG0_4K		TCR_TG0_4K
@@ -120,63 +121,150 @@
 #define VTCR_EL2_IRGN0_WBWA	TCR_IRGN0_WBWA
 #define VTCR_EL2_SL0_SHIFT	6
 #define VTCR_EL2_SL0_MASK	(3 << VTCR_EL2_SL0_SHIFT)
-#define VTCR_EL2_SL0_LVL1	(1 << VTCR_EL2_SL0_SHIFT)
 #define VTCR_EL2_T0SZ_MASK	0x3f
-#define VTCR_EL2_T0SZ_40B	24
 #define VTCR_EL2_VS_SHIFT	19
 #define VTCR_EL2_VS_8BIT	(0 << VTCR_EL2_VS_SHIFT)
 #define VTCR_EL2_VS_16BIT	(1 << VTCR_EL2_VS_SHIFT)
 
+#define VTCR_EL2_T0SZ(x)	TCR_T0SZ(x)
+
 /*
  * We configure the Stage-2 page tables to always restrict the IPA space to be
  * 40 bits wide (T0SZ = 24).  Systems with a PARange smaller than 40 bits are
  * not known to exist and will break with this configuration.
  *
- * VTCR_EL2.PS is extracted from ID_AA64MMFR0_EL1.PARange at boot time
- * (see hyp-init.S).
+ * The VTCR_EL2 is configured per VM and is initialised in kvm_arm_setup_stage2().
  *
  * Note that when using 4K pages, we concatenate two first level page tables
  * together. With 16K pages, we concatenate 16 first level page tables.
  *
- * The magic numbers used for VTTBR_X in this patch can be found in Tables
- * D4-23 and D4-25 in ARM DDI 0487A.b.
  */
 
-#define VTCR_EL2_T0SZ_IPA	VTCR_EL2_T0SZ_40B
 #define VTCR_EL2_COMMON_BITS	(VTCR_EL2_SH0_INNER | VTCR_EL2_ORGN0_WBWA | \
 				 VTCR_EL2_IRGN0_WBWA | VTCR_EL2_RES1)
 
-#ifdef CONFIG_ARM64_64K_PAGES
 /*
- * Stage2 translation configuration:
- * 64kB pages (TG0 = 1)
- * 2 level page tables (SL = 1)
+ * VTCR_EL2:SL0 indicates the entry level for Stage2 translation.
+ * Interestingly, it depends on the page size.
+ * See D.10.2.121, VTCR_EL2, in ARM DDI 0487C.a
+ *
+ *	-----------------------------------------
+ *	| Entry level		|  4K  | 16K/64K |
+ *	------------------------------------------
+ *	| Level: 0		|  2   |   -     |
+ *	------------------------------------------
+ *	| Level: 1		|  1   |   2     |
+ *	------------------------------------------
+ *	| Level: 2		|  0   |   1     |
+ *	------------------------------------------
+ *	| Level: 3		|  -   |   0     |
+ *	------------------------------------------
+ *
+ * The table roughly translates to :
+ *
+ *	SL0(PAGE_SIZE, Entry_level) = TGRAN_SL0_BASE - Entry_Level
+ *
+ * Where TGRAN_SL0_BASE is a magic number depending on the page size:
+ * 	TGRAN_SL0_BASE(4K) = 2
+ *	TGRAN_SL0_BASE(16K) = 3
+ *	TGRAN_SL0_BASE(64K) = 3
+ * provided we take care of ruling out the unsupported cases and
+ * Entry_Level = 4 - Number_of_levels.
+ *
  */
-#define VTCR_EL2_TGRAN_FLAGS		(VTCR_EL2_TG0_64K | VTCR_EL2_SL0_LVL1)
-#define VTTBR_X_TGRAN_MAGIC		38
+#ifdef CONFIG_ARM64_64K_PAGES
+
+#define VTCR_EL2_TGRAN			VTCR_EL2_TG0_64K
+#define VTCR_EL2_TGRAN_SL0_BASE		3UL
+
 #elif defined(CONFIG_ARM64_16K_PAGES)
-/*
- * Stage2 translation configuration:
- * 16kB pages (TG0 = 2)
- * 2 level page tables (SL = 1)
- */
-#define VTCR_EL2_TGRAN_FLAGS		(VTCR_EL2_TG0_16K | VTCR_EL2_SL0_LVL1)
-#define VTTBR_X_TGRAN_MAGIC		42
+
+#define VTCR_EL2_TGRAN			VTCR_EL2_TG0_16K
+#define VTCR_EL2_TGRAN_SL0_BASE		3UL
+
 #else	/* 4K */
-/*
- * Stage2 translation configuration:
- * 4kB pages (TG0 = 0)
- * 3 level page tables (SL = 1)
- */
-#define VTCR_EL2_TGRAN_FLAGS		(VTCR_EL2_TG0_4K | VTCR_EL2_SL0_LVL1)
-#define VTTBR_X_TGRAN_MAGIC		37
+
+#define VTCR_EL2_TGRAN			VTCR_EL2_TG0_4K
+#define VTCR_EL2_TGRAN_SL0_BASE		2UL
+
 #endif
 
-#define VTCR_EL2_FLAGS			(VTCR_EL2_COMMON_BITS | VTCR_EL2_TGRAN_FLAGS)
-#define VTTBR_X				(VTTBR_X_TGRAN_MAGIC - VTCR_EL2_T0SZ_IPA)
+#define VTCR_EL2_LVLS_TO_SL0(levels)	\
+	((VTCR_EL2_TGRAN_SL0_BASE - (4 - (levels))) << VTCR_EL2_SL0_SHIFT)
+#define VTCR_EL2_SL0_TO_LVLS(sl0)	\
+	((sl0) + 4 - VTCR_EL2_TGRAN_SL0_BASE)
+#define VTCR_EL2_LVLS(vtcr)		\
+	VTCR_EL2_SL0_TO_LVLS(((vtcr) & VTCR_EL2_SL0_MASK) >> VTCR_EL2_SL0_SHIFT)
+
+#define VTCR_EL2_FLAGS			(VTCR_EL2_COMMON_BITS | VTCR_EL2_TGRAN)
+#define VTCR_EL2_IPA(vtcr)		(64 - ((vtcr) & VTCR_EL2_T0SZ_MASK))
+
+/*
+ * ARM VMSAv8-64 defines an algorithm for finding the translation table
+ * descriptors in section D4.2.8 in ARM DDI 0487C.a.
+ *
+ * The algorithm defines the expectations on the translation table
+ * addresses for each level, based on PAGE_SIZE, entry level
+ * and the translation table size (T0SZ). The variable "x" in the
+ * algorithm determines the alignment of a table base address at a given
+ * level and thus determines the alignment of VTTBR:BADDR for stage2
+ * page table entry level.
+ * Since the number of bits resolved at the entry level could vary
+ * depending on the T0SZ, the value of "x" is defined based on a
+ * Magic constant for a given PAGE_SIZE and Entry Level. The
+ * intermediate levels must be always aligned to the PAGE_SIZE (i.e,
+ * x = PAGE_SHIFT).
+ *
+ * The value of "x" for entry level is calculated as :
+ *    x = Magic_N - T0SZ
+ *
+ * where Magic_N is an integer depending on the page size and the entry
+ * level of the page table as below:
+ *
+ *	--------------------------------------------
+ *	| Entry level		|  4K    16K   64K |
+ *	--------------------------------------------
+ *	| Level: 0 (4 levels)	| 28   |  -  |  -  |
+ *	--------------------------------------------
+ *	| Level: 1 (3 levels)	| 37   | 31  | 25  |
+ *	--------------------------------------------
+ *	| Level: 2 (2 levels)	| 46   | 42  | 38  |
+ *	--------------------------------------------
+ *	| Level: 3 (1 level)	| -    | 53  | 51  |
+ *	--------------------------------------------
+ *
+ * We have a magic formula for the Magic_N below:
+ *
+ *  Magic_N(PAGE_SIZE, Level) = 64 - ((PAGE_SHIFT - 3) * Number_of_levels)
+ *
+ * where Number_of_levels = (4 - Level). We are only interested in the
+ * value for Entry_Level for the stage2 page table.
+ *
+ * So, given that T0SZ = (64 - IPA_SHIFT), we can compute 'x' as follows:
+ *
+ *	x = (64 - ((PAGE_SHIFT - 3) * Number_of_levels)) - (64 - IPA_SHIFT)
+ *	  = IPA_SHIFT - ((PAGE_SHIFT - 3) * Number of levels)
+ *
+ * Here is one way to explain the Magic Formula:
+ *
+ *  x = log2(Size_of_Entry_Level_Table)
+ *
+ * Since, we can resolve (PAGE_SHIFT - 3) bits at each level, and another
+ * PAGE_SHIFT bits in the PTE, we have :
+ *
+ *  Bits_Entry_level = IPA_SHIFT - ((PAGE_SHIFT - 3) * (n - 1) + PAGE_SHIFT)
+ *		     = IPA_SHIFT - (PAGE_SHIFT - 3) * n - 3
+ *  where n = number of levels, and since each pointer is 8bytes, we have:
+ *
+ *  x = Bits_Entry_Level + 3
+ *    = IPA_SHIFT - (PAGE_SHIFT - 3) * n
+ *
+ * The only constraint here is that, we have to find the number of page table
+ * levels for a given IPA size (which we do, see stage2_pt_levels())
+ */
+#define ARM64_VTTBR_X(ipa, levels)	((ipa) - ((levels) * (PAGE_SHIFT - 3)))
 
 #define VTTBR_CNP_BIT     (UL(1))
-#define VTTBR_BADDR_MASK  (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_X)
 #define VTTBR_VMID_SHIFT  (UL(48))
 #define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)
 
@@ -224,6 +312,13 @@
 
 /* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */
 #define HPFAR_MASK	(~UL(0xf))
+/*
+ * We have
+ *	PAR	[PA_Shift - 1	: 12] = PA	[PA_Shift - 1 : 12]
+ *	HPFAR	[PA_Shift - 9	: 4]  = FIPA	[PA_Shift - 1 : 12]
+ */
+#define PAR_TO_HPFAR(par)		\
+	(((par) & GENMASK_ULL(PHYS_MASK_SHIFT - 1, 12)) >> 8)
 
 #define kvm_arm_exception_type	\
 	{0, "IRQ" }, 		\