1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2021 Google LLC 4 * Author: Fuad Tabba <tabba@google.com> 5 */ 6 7 #ifndef __ARM64_KVM_FIXED_CONFIG_H__ 8 #define __ARM64_KVM_FIXED_CONFIG_H__ 9 10 #include <asm/sysreg.h> 11 12 /* 13 * This file contains definitions for features to be allowed or restricted for 14 * guest virtual machines, depending on the mode KVM is running in and on the 15 * type of guest that is running. 16 * 17 * The ALLOW masks represent a bitmask of feature fields that are allowed 18 * without any restrictions as long as they are supported by the system. 19 * 20 * The RESTRICT_UNSIGNED masks, if present, represent unsigned fields for 21 * features that are restricted to support at most the specified feature. 22 * 23 * If a feature field is not present in either, than it is not supported. 24 * 25 * The approach taken for protected VMs is to allow features that are: 26 * - Needed by common Linux distributions (e.g., floating point) 27 * - Trivial to support, e.g., supporting the feature does not introduce or 28 * require tracking of additional state in KVM 29 * - Cannot be trapped or prevent the guest from using anyway 30 */ 31 32 /* 33 * Allow for protected VMs: 34 * - Floating-point and Advanced SIMD 35 * - Data Independent Timing 36 */ 37 #define PVM_ID_AA64PFR0_ALLOW (\ 38 ARM64_FEATURE_MASK(ID_AA64PFR0_FP) | \ 39 ARM64_FEATURE_MASK(ID_AA64PFR0_ASIMD) | \ 40 ARM64_FEATURE_MASK(ID_AA64PFR0_DIT) \ 41 ) 42 43 /* 44 * Restrict to the following *unsigned* features for protected VMs: 45 * - AArch64 guests only (no support for AArch32 guests): 46 * AArch32 adds complexity in trap handling, emulation, condition codes, 47 * etc... 48 * - RAS (v1) 49 * Supported by KVM 50 */ 51 #define PVM_ID_AA64PFR0_RESTRICT_UNSIGNED (\ 52 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL0), ID_AA64PFR0_ELx_64BIT_ONLY) | \ 53 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1), ID_AA64PFR0_ELx_64BIT_ONLY) | \ 54 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL2), ID_AA64PFR0_ELx_64BIT_ONLY) | \ 55 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL3), ID_AA64PFR0_ELx_64BIT_ONLY) | \ 56 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_RAS), ID_AA64PFR0_RAS_V1) \ 57 ) 58 59 /* 60 * Allow for protected VMs: 61 * - Branch Target Identification 62 * - Speculative Store Bypassing 63 */ 64 #define PVM_ID_AA64PFR1_ALLOW (\ 65 ARM64_FEATURE_MASK(ID_AA64PFR1_BT) | \ 66 ARM64_FEATURE_MASK(ID_AA64PFR1_SSBS) \ 67 ) 68 69 /* 70 * Allow for protected VMs: 71 * - Mixed-endian 72 * - Distinction between Secure and Non-secure Memory 73 * - Mixed-endian at EL0 only 74 * - Non-context synchronizing exception entry and exit 75 */ 76 #define PVM_ID_AA64MMFR0_ALLOW (\ 77 ARM64_FEATURE_MASK(ID_AA64MMFR0_BIGENDEL) | \ 78 ARM64_FEATURE_MASK(ID_AA64MMFR0_SNSMEM) | \ 79 ARM64_FEATURE_MASK(ID_AA64MMFR0_BIGENDEL0) | \ 80 ARM64_FEATURE_MASK(ID_AA64MMFR0_EXS) \ 81 ) 82 83 /* 84 * Restrict to the following *unsigned* features for protected VMs: 85 * - 40-bit IPA 86 * - 16-bit ASID 87 */ 88 #define PVM_ID_AA64MMFR0_RESTRICT_UNSIGNED (\ 89 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64MMFR0_PARANGE), ID_AA64MMFR0_PARANGE_40) | \ 90 FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64MMFR0_ASID), ID_AA64MMFR0_ASID_16) \ 91 ) 92 93 /* 94 * Allow for protected VMs: 95 * - Hardware translation table updates to Access flag and Dirty state 96 * - Number of VMID bits from CPU 97 * - Hierarchical Permission Disables 98 * - Privileged Access Never 99 * - SError interrupt exceptions from speculative reads 100 * - Enhanced Translation Synchronization 101 */ 102 #define PVM_ID_AA64MMFR1_ALLOW (\ 103 ARM64_FEATURE_MASK(ID_AA64MMFR1_HADBS) | \ 104 ARM64_FEATURE_MASK(ID_AA64MMFR1_VMIDBITS) | \ 105 ARM64_FEATURE_MASK(ID_AA64MMFR1_HPD) | \ 106 ARM64_FEATURE_MASK(ID_AA64MMFR1_PAN) | \ 107 ARM64_FEATURE_MASK(ID_AA64MMFR1_SPECSEI) | \ 108 ARM64_FEATURE_MASK(ID_AA64MMFR1_ETS) \ 109 ) 110 111 /* 112 * Allow for protected VMs: 113 * - Common not Private translations 114 * - User Access Override 115 * - IESB bit in the SCTLR_ELx registers 116 * - Unaligned single-copy atomicity and atomic functions 117 * - ESR_ELx.EC value on an exception by read access to feature ID space 118 * - TTL field in address operations. 119 * - Break-before-make sequences when changing translation block size 120 * - E0PDx mechanism 121 */ 122 #define PVM_ID_AA64MMFR2_ALLOW (\ 123 ARM64_FEATURE_MASK(ID_AA64MMFR2_CNP) | \ 124 ARM64_FEATURE_MASK(ID_AA64MMFR2_UAO) | \ 125 ARM64_FEATURE_MASK(ID_AA64MMFR2_IESB) | \ 126 ARM64_FEATURE_MASK(ID_AA64MMFR2_AT) | \ 127 ARM64_FEATURE_MASK(ID_AA64MMFR2_IDS) | \ 128 ARM64_FEATURE_MASK(ID_AA64MMFR2_TTL) | \ 129 ARM64_FEATURE_MASK(ID_AA64MMFR2_BBM) | \ 130 ARM64_FEATURE_MASK(ID_AA64MMFR2_E0PD) \ 131 ) 132 133 /* 134 * No support for Scalable Vectors for protected VMs: 135 * Requires additional support from KVM, e.g., context-switching and 136 * trapping at EL2 137 */ 138 #define PVM_ID_AA64ZFR0_ALLOW (0ULL) 139 140 /* 141 * No support for debug, including breakpoints, and watchpoints for protected 142 * VMs: 143 * The Arm architecture mandates support for at least the Armv8 debug 144 * architecture, which would include at least 2 hardware breakpoints and 145 * watchpoints. Providing that support to protected guests adds 146 * considerable state and complexity. Therefore, the reserved value of 0 is 147 * used for debug-related fields. 148 */ 149 #define PVM_ID_AA64DFR0_ALLOW (0ULL) 150 #define PVM_ID_AA64DFR1_ALLOW (0ULL) 151 152 /* 153 * No support for implementation defined features. 154 */ 155 #define PVM_ID_AA64AFR0_ALLOW (0ULL) 156 #define PVM_ID_AA64AFR1_ALLOW (0ULL) 157 158 /* 159 * No restrictions on instructions implemented in AArch64. 160 */ 161 #define PVM_ID_AA64ISAR0_ALLOW (\ 162 ARM64_FEATURE_MASK(ID_AA64ISAR0_AES) | \ 163 ARM64_FEATURE_MASK(ID_AA64ISAR0_SHA1) | \ 164 ARM64_FEATURE_MASK(ID_AA64ISAR0_SHA2) | \ 165 ARM64_FEATURE_MASK(ID_AA64ISAR0_CRC32) | \ 166 ARM64_FEATURE_MASK(ID_AA64ISAR0_ATOMICS) | \ 167 ARM64_FEATURE_MASK(ID_AA64ISAR0_RDM) | \ 168 ARM64_FEATURE_MASK(ID_AA64ISAR0_SHA3) | \ 169 ARM64_FEATURE_MASK(ID_AA64ISAR0_SM3) | \ 170 ARM64_FEATURE_MASK(ID_AA64ISAR0_SM4) | \ 171 ARM64_FEATURE_MASK(ID_AA64ISAR0_DP) | \ 172 ARM64_FEATURE_MASK(ID_AA64ISAR0_FHM) | \ 173 ARM64_FEATURE_MASK(ID_AA64ISAR0_TS) | \ 174 ARM64_FEATURE_MASK(ID_AA64ISAR0_TLB) | \ 175 ARM64_FEATURE_MASK(ID_AA64ISAR0_RNDR) \ 176 ) 177 178 #define PVM_ID_AA64ISAR1_ALLOW (\ 179 ARM64_FEATURE_MASK(ID_AA64ISAR1_DPB) | \ 180 ARM64_FEATURE_MASK(ID_AA64ISAR1_APA) | \ 181 ARM64_FEATURE_MASK(ID_AA64ISAR1_API) | \ 182 ARM64_FEATURE_MASK(ID_AA64ISAR1_JSCVT) | \ 183 ARM64_FEATURE_MASK(ID_AA64ISAR1_FCMA) | \ 184 ARM64_FEATURE_MASK(ID_AA64ISAR1_LRCPC) | \ 185 ARM64_FEATURE_MASK(ID_AA64ISAR1_GPA) | \ 186 ARM64_FEATURE_MASK(ID_AA64ISAR1_GPI) | \ 187 ARM64_FEATURE_MASK(ID_AA64ISAR1_FRINTTS) | \ 188 ARM64_FEATURE_MASK(ID_AA64ISAR1_SB) | \ 189 ARM64_FEATURE_MASK(ID_AA64ISAR1_SPECRES) | \ 190 ARM64_FEATURE_MASK(ID_AA64ISAR1_BF16) | \ 191 ARM64_FEATURE_MASK(ID_AA64ISAR1_DGH) | \ 192 ARM64_FEATURE_MASK(ID_AA64ISAR1_I8MM) \ 193 ) 194 195 #define PVM_ID_AA64ISAR2_ALLOW (\ 196 ARM64_FEATURE_MASK(ID_AA64ISAR2_GPA3) | \ 197 ARM64_FEATURE_MASK(ID_AA64ISAR2_APA3) \ 198 ) 199 200 u64 pvm_read_id_reg(const struct kvm_vcpu *vcpu, u32 id); 201 bool kvm_handle_pvm_sysreg(struct kvm_vcpu *vcpu, u64 *exit_code); 202 bool kvm_handle_pvm_restricted(struct kvm_vcpu *vcpu, u64 *exit_code); 203 int kvm_check_pvm_sysreg_table(void); 204 205 #endif /* __ARM64_KVM_FIXED_CONFIG_H__ */ 206