1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef ARCH_X86_KVM_CPUID_H 3 #define ARCH_X86_KVM_CPUID_H 4 5 #include "x86.h" 6 #include <asm/cpu.h> 7 #include <asm/processor.h> 8 #include <uapi/asm/kvm_para.h> 9 10 extern u32 kvm_cpu_caps[NCAPINTS] __read_mostly; 11 void kvm_set_cpu_caps(void); 12 13 void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu); 14 void kvm_update_pv_runtime(struct kvm_vcpu *vcpu); 15 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, 16 u32 function, u32 index); 17 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid, 18 struct kvm_cpuid_entry2 __user *entries, 19 unsigned int type); 20 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, 21 struct kvm_cpuid *cpuid, 22 struct kvm_cpuid_entry __user *entries); 23 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, 24 struct kvm_cpuid2 *cpuid, 25 struct kvm_cpuid_entry2 __user *entries); 26 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, 27 struct kvm_cpuid2 *cpuid, 28 struct kvm_cpuid_entry2 __user *entries); 29 bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, 30 u32 *ecx, u32 *edx, bool exact_only); 31 32 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu); 33 34 static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu) 35 { 36 return vcpu->arch.maxphyaddr; 37 } 38 39 static inline bool kvm_vcpu_is_illegal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa) 40 { 41 return (gpa >= BIT_ULL(cpuid_maxphyaddr(vcpu))); 42 } 43 44 struct cpuid_reg { 45 u32 function; 46 u32 index; 47 int reg; 48 }; 49 50 static const struct cpuid_reg reverse_cpuid[] = { 51 [CPUID_1_EDX] = { 1, 0, CPUID_EDX}, 52 [CPUID_8000_0001_EDX] = {0x80000001, 0, CPUID_EDX}, 53 [CPUID_8086_0001_EDX] = {0x80860001, 0, CPUID_EDX}, 54 [CPUID_1_ECX] = { 1, 0, CPUID_ECX}, 55 [CPUID_C000_0001_EDX] = {0xc0000001, 0, CPUID_EDX}, 56 [CPUID_8000_0001_ECX] = {0x80000001, 0, CPUID_ECX}, 57 [CPUID_7_0_EBX] = { 7, 0, CPUID_EBX}, 58 [CPUID_D_1_EAX] = { 0xd, 1, CPUID_EAX}, 59 [CPUID_8000_0008_EBX] = {0x80000008, 0, CPUID_EBX}, 60 [CPUID_6_EAX] = { 6, 0, CPUID_EAX}, 61 [CPUID_8000_000A_EDX] = {0x8000000a, 0, CPUID_EDX}, 62 [CPUID_7_ECX] = { 7, 0, CPUID_ECX}, 63 [CPUID_8000_0007_EBX] = {0x80000007, 0, CPUID_EBX}, 64 [CPUID_7_EDX] = { 7, 0, CPUID_EDX}, 65 [CPUID_7_1_EAX] = { 7, 1, CPUID_EAX}, 66 }; 67 68 /* 69 * Reverse CPUID and its derivatives can only be used for hardware-defined 70 * feature words, i.e. words whose bits directly correspond to a CPUID leaf. 71 * Retrieving a feature bit or masking guest CPUID from a Linux-defined word 72 * is nonsensical as the bit number/mask is an arbitrary software-defined value 73 * and can't be used by KVM to query/control guest capabilities. And obviously 74 * the leaf being queried must have an entry in the lookup table. 75 */ 76 static __always_inline void reverse_cpuid_check(unsigned int x86_leaf) 77 { 78 BUILD_BUG_ON(x86_leaf == CPUID_LNX_1); 79 BUILD_BUG_ON(x86_leaf == CPUID_LNX_2); 80 BUILD_BUG_ON(x86_leaf == CPUID_LNX_3); 81 BUILD_BUG_ON(x86_leaf == CPUID_LNX_4); 82 BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid)); 83 BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0); 84 } 85 86 /* 87 * Retrieve the bit mask from an X86_FEATURE_* definition. Features contain 88 * the hardware defined bit number (stored in bits 4:0) and a software defined 89 * "word" (stored in bits 31:5). The word is used to index into arrays of 90 * bit masks that hold the per-cpu feature capabilities, e.g. this_cpu_has(). 91 */ 92 static __always_inline u32 __feature_bit(int x86_feature) 93 { 94 reverse_cpuid_check(x86_feature / 32); 95 return 1 << (x86_feature & 31); 96 } 97 98 #define feature_bit(name) __feature_bit(X86_FEATURE_##name) 99 100 static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned int x86_feature) 101 { 102 unsigned int x86_leaf = x86_feature / 32; 103 104 reverse_cpuid_check(x86_leaf); 105 return reverse_cpuid[x86_leaf]; 106 } 107 108 static __always_inline u32 *__cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry, 109 u32 reg) 110 { 111 switch (reg) { 112 case CPUID_EAX: 113 return &entry->eax; 114 case CPUID_EBX: 115 return &entry->ebx; 116 case CPUID_ECX: 117 return &entry->ecx; 118 case CPUID_EDX: 119 return &entry->edx; 120 default: 121 BUILD_BUG(); 122 return NULL; 123 } 124 } 125 126 static __always_inline u32 *cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry, 127 unsigned int x86_feature) 128 { 129 const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature); 130 131 return __cpuid_entry_get_reg(entry, cpuid.reg); 132 } 133 134 static __always_inline u32 cpuid_entry_get(struct kvm_cpuid_entry2 *entry, 135 unsigned int x86_feature) 136 { 137 u32 *reg = cpuid_entry_get_reg(entry, x86_feature); 138 139 return *reg & __feature_bit(x86_feature); 140 } 141 142 static __always_inline bool cpuid_entry_has(struct kvm_cpuid_entry2 *entry, 143 unsigned int x86_feature) 144 { 145 return cpuid_entry_get(entry, x86_feature); 146 } 147 148 static __always_inline void cpuid_entry_clear(struct kvm_cpuid_entry2 *entry, 149 unsigned int x86_feature) 150 { 151 u32 *reg = cpuid_entry_get_reg(entry, x86_feature); 152 153 *reg &= ~__feature_bit(x86_feature); 154 } 155 156 static __always_inline void cpuid_entry_set(struct kvm_cpuid_entry2 *entry, 157 unsigned int x86_feature) 158 { 159 u32 *reg = cpuid_entry_get_reg(entry, x86_feature); 160 161 *reg |= __feature_bit(x86_feature); 162 } 163 164 static __always_inline void cpuid_entry_change(struct kvm_cpuid_entry2 *entry, 165 unsigned int x86_feature, 166 bool set) 167 { 168 u32 *reg = cpuid_entry_get_reg(entry, x86_feature); 169 170 /* 171 * Open coded instead of using cpuid_entry_{clear,set}() to coerce the 172 * compiler into using CMOV instead of Jcc when possible. 173 */ 174 if (set) 175 *reg |= __feature_bit(x86_feature); 176 else 177 *reg &= ~__feature_bit(x86_feature); 178 } 179 180 static __always_inline void cpuid_entry_override(struct kvm_cpuid_entry2 *entry, 181 enum cpuid_leafs leaf) 182 { 183 u32 *reg = cpuid_entry_get_reg(entry, leaf * 32); 184 185 BUILD_BUG_ON(leaf >= ARRAY_SIZE(kvm_cpu_caps)); 186 *reg = kvm_cpu_caps[leaf]; 187 } 188 189 static __always_inline u32 *guest_cpuid_get_register(struct kvm_vcpu *vcpu, 190 unsigned int x86_feature) 191 { 192 const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature); 193 struct kvm_cpuid_entry2 *entry; 194 195 entry = kvm_find_cpuid_entry(vcpu, cpuid.function, cpuid.index); 196 if (!entry) 197 return NULL; 198 199 return __cpuid_entry_get_reg(entry, cpuid.reg); 200 } 201 202 static __always_inline bool guest_cpuid_has(struct kvm_vcpu *vcpu, 203 unsigned int x86_feature) 204 { 205 u32 *reg; 206 207 reg = guest_cpuid_get_register(vcpu, x86_feature); 208 if (!reg) 209 return false; 210 211 return *reg & __feature_bit(x86_feature); 212 } 213 214 static __always_inline void guest_cpuid_clear(struct kvm_vcpu *vcpu, 215 unsigned int x86_feature) 216 { 217 u32 *reg; 218 219 reg = guest_cpuid_get_register(vcpu, x86_feature); 220 if (reg) 221 *reg &= ~__feature_bit(x86_feature); 222 } 223 224 static inline bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu) 225 { 226 struct kvm_cpuid_entry2 *best; 227 228 best = kvm_find_cpuid_entry(vcpu, 0, 0); 229 return best && 230 (is_guest_vendor_amd(best->ebx, best->ecx, best->edx) || 231 is_guest_vendor_hygon(best->ebx, best->ecx, best->edx)); 232 } 233 234 static inline int guest_cpuid_family(struct kvm_vcpu *vcpu) 235 { 236 struct kvm_cpuid_entry2 *best; 237 238 best = kvm_find_cpuid_entry(vcpu, 0x1, 0); 239 if (!best) 240 return -1; 241 242 return x86_family(best->eax); 243 } 244 245 static inline int guest_cpuid_model(struct kvm_vcpu *vcpu) 246 { 247 struct kvm_cpuid_entry2 *best; 248 249 best = kvm_find_cpuid_entry(vcpu, 0x1, 0); 250 if (!best) 251 return -1; 252 253 return x86_model(best->eax); 254 } 255 256 static inline int guest_cpuid_stepping(struct kvm_vcpu *vcpu) 257 { 258 struct kvm_cpuid_entry2 *best; 259 260 best = kvm_find_cpuid_entry(vcpu, 0x1, 0); 261 if (!best) 262 return -1; 263 264 return x86_stepping(best->eax); 265 } 266 267 static inline bool guest_has_spec_ctrl_msr(struct kvm_vcpu *vcpu) 268 { 269 return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) || 270 guest_cpuid_has(vcpu, X86_FEATURE_AMD_STIBP) || 271 guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBRS) || 272 guest_cpuid_has(vcpu, X86_FEATURE_AMD_SSBD)); 273 } 274 275 static inline bool guest_has_pred_cmd_msr(struct kvm_vcpu *vcpu) 276 { 277 return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) || 278 guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBPB)); 279 } 280 281 static inline bool supports_cpuid_fault(struct kvm_vcpu *vcpu) 282 { 283 return vcpu->arch.msr_platform_info & MSR_PLATFORM_INFO_CPUID_FAULT; 284 } 285 286 static inline bool cpuid_fault_enabled(struct kvm_vcpu *vcpu) 287 { 288 return vcpu->arch.msr_misc_features_enables & 289 MSR_MISC_FEATURES_ENABLES_CPUID_FAULT; 290 } 291 292 static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature) 293 { 294 unsigned int x86_leaf = x86_feature / 32; 295 296 reverse_cpuid_check(x86_leaf); 297 kvm_cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature); 298 } 299 300 static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature) 301 { 302 unsigned int x86_leaf = x86_feature / 32; 303 304 reverse_cpuid_check(x86_leaf); 305 kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature); 306 } 307 308 static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature) 309 { 310 unsigned int x86_leaf = x86_feature / 32; 311 312 reverse_cpuid_check(x86_leaf); 313 return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature); 314 } 315 316 static __always_inline bool kvm_cpu_cap_has(unsigned int x86_feature) 317 { 318 return !!kvm_cpu_cap_get(x86_feature); 319 } 320 321 static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature) 322 { 323 if (boot_cpu_has(x86_feature)) 324 kvm_cpu_cap_set(x86_feature); 325 } 326 327 static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa) 328 { 329 return PAGE_ALIGNED(gpa) && !(gpa >> cpuid_maxphyaddr(vcpu)); 330 } 331 332 static __always_inline bool guest_pv_has(struct kvm_vcpu *vcpu, 333 unsigned int kvm_feature) 334 { 335 if (!vcpu->arch.pv_cpuid.enforce) 336 return true; 337 338 return vcpu->arch.pv_cpuid.features & (1u << kvm_feature); 339 } 340 341 #endif 342