1 /****************************************************************************** 2 * emulate.c 3 * 4 * Generic x86 (32-bit and 64-bit) instruction decoder and emulator. 5 * 6 * Copyright (c) 2005 Keir Fraser 7 * 8 * Linux coding style, mod r/m decoder, segment base fixes, real-mode 9 * privileged instructions: 10 * 11 * Copyright (C) 2006 Qumranet 12 * Copyright 2010 Red Hat, Inc. and/or its affiliates. 13 * 14 * Avi Kivity <avi@qumranet.com> 15 * Yaniv Kamay <yaniv@qumranet.com> 16 * 17 * This work is licensed under the terms of the GNU GPL, version 2. See 18 * the COPYING file in the top-level directory. 19 * 20 * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4 21 */ 22 23 #include <linux/kvm_host.h> 24 #include "kvm_cache_regs.h" 25 #include <linux/module.h> 26 #include <asm/kvm_emulate.h> 27 #include <linux/stringify.h> 28 #include <asm/debugreg.h> 29 30 #include "x86.h" 31 #include "tss.h" 32 33 /* 34 * Operand types 35 */ 36 #define OpNone 0ull 37 #define OpImplicit 1ull /* No generic decode */ 38 #define OpReg 2ull /* Register */ 39 #define OpMem 3ull /* Memory */ 40 #define OpAcc 4ull /* Accumulator: AL/AX/EAX/RAX */ 41 #define OpDI 5ull /* ES:DI/EDI/RDI */ 42 #define OpMem64 6ull /* Memory, 64-bit */ 43 #define OpImmUByte 7ull /* Zero-extended 8-bit immediate */ 44 #define OpDX 8ull /* DX register */ 45 #define OpCL 9ull /* CL register (for shifts) */ 46 #define OpImmByte 10ull /* 8-bit sign extended immediate */ 47 #define OpOne 11ull /* Implied 1 */ 48 #define OpImm 12ull /* Sign extended up to 32-bit immediate */ 49 #define OpMem16 13ull /* Memory operand (16-bit). */ 50 #define OpMem32 14ull /* Memory operand (32-bit). */ 51 #define OpImmU 15ull /* Immediate operand, zero extended */ 52 #define OpSI 16ull /* SI/ESI/RSI */ 53 #define OpImmFAddr 17ull /* Immediate far address */ 54 #define OpMemFAddr 18ull /* Far address in memory */ 55 #define OpImmU16 19ull /* Immediate operand, 16 bits, zero extended */ 56 #define OpES 20ull /* ES */ 57 #define OpCS 21ull /* CS */ 58 #define OpSS 22ull /* SS */ 59 #define OpDS 23ull /* DS */ 60 #define OpFS 24ull /* FS */ 61 #define OpGS 25ull /* GS */ 62 #define OpMem8 26ull /* 8-bit zero extended memory operand */ 63 #define OpImm64 27ull /* Sign extended 16/32/64-bit immediate */ 64 #define OpXLat 28ull /* memory at BX/EBX/RBX + zero-extended AL */ 65 #define OpAccLo 29ull /* Low part of extended acc (AX/AX/EAX/RAX) */ 66 #define OpAccHi 30ull /* High part of extended acc (-/DX/EDX/RDX) */ 67 68 #define OpBits 5 /* Width of operand field */ 69 #define OpMask ((1ull << OpBits) - 1) 70 71 /* 72 * Opcode effective-address decode tables. 73 * Note that we only emulate instructions that have at least one memory 74 * operand (excluding implicit stack references). We assume that stack 75 * references and instruction fetches will never occur in special memory 76 * areas that require emulation. So, for example, 'mov <imm>,<reg>' need 77 * not be handled. 78 */ 79 80 /* Operand sizes: 8-bit operands or specified/overridden size. */ 81 #define ByteOp (1<<0) /* 8-bit operands. */ 82 /* Destination operand type. */ 83 #define DstShift 1 84 #define ImplicitOps (OpImplicit << DstShift) 85 #define DstReg (OpReg << DstShift) 86 #define DstMem (OpMem << DstShift) 87 #define DstAcc (OpAcc << DstShift) 88 #define DstDI (OpDI << DstShift) 89 #define DstMem64 (OpMem64 << DstShift) 90 #define DstMem16 (OpMem16 << DstShift) 91 #define DstImmUByte (OpImmUByte << DstShift) 92 #define DstDX (OpDX << DstShift) 93 #define DstAccLo (OpAccLo << DstShift) 94 #define DstMask (OpMask << DstShift) 95 /* Source operand type. */ 96 #define SrcShift 6 97 #define SrcNone (OpNone << SrcShift) 98 #define SrcReg (OpReg << SrcShift) 99 #define SrcMem (OpMem << SrcShift) 100 #define SrcMem16 (OpMem16 << SrcShift) 101 #define SrcMem32 (OpMem32 << SrcShift) 102 #define SrcImm (OpImm << SrcShift) 103 #define SrcImmByte (OpImmByte << SrcShift) 104 #define SrcOne (OpOne << SrcShift) 105 #define SrcImmUByte (OpImmUByte << SrcShift) 106 #define SrcImmU (OpImmU << SrcShift) 107 #define SrcSI (OpSI << SrcShift) 108 #define SrcXLat (OpXLat << SrcShift) 109 #define SrcImmFAddr (OpImmFAddr << SrcShift) 110 #define SrcMemFAddr (OpMemFAddr << SrcShift) 111 #define SrcAcc (OpAcc << SrcShift) 112 #define SrcImmU16 (OpImmU16 << SrcShift) 113 #define SrcImm64 (OpImm64 << SrcShift) 114 #define SrcDX (OpDX << SrcShift) 115 #define SrcMem8 (OpMem8 << SrcShift) 116 #define SrcAccHi (OpAccHi << SrcShift) 117 #define SrcMask (OpMask << SrcShift) 118 #define BitOp (1<<11) 119 #define MemAbs (1<<12) /* Memory operand is absolute displacement */ 120 #define String (1<<13) /* String instruction (rep capable) */ 121 #define Stack (1<<14) /* Stack instruction (push/pop) */ 122 #define GroupMask (7<<15) /* Opcode uses one of the group mechanisms */ 123 #define Group (1<<15) /* Bits 3:5 of modrm byte extend opcode */ 124 #define GroupDual (2<<15) /* Alternate decoding of mod == 3 */ 125 #define Prefix (3<<15) /* Instruction varies with 66/f2/f3 prefix */ 126 #define RMExt (4<<15) /* Opcode extension in ModRM r/m if mod == 3 */ 127 #define Escape (5<<15) /* Escape to coprocessor instruction */ 128 #define InstrDual (6<<15) /* Alternate instruction decoding of mod == 3 */ 129 #define ModeDual (7<<15) /* Different instruction for 32/64 bit */ 130 #define Sse (1<<18) /* SSE Vector instruction */ 131 /* Generic ModRM decode. */ 132 #define ModRM (1<<19) 133 /* Destination is only written; never read. */ 134 #define Mov (1<<20) 135 /* Misc flags */ 136 #define Prot (1<<21) /* instruction generates #UD if not in prot-mode */ 137 #define EmulateOnUD (1<<22) /* Emulate if unsupported by the host */ 138 #define NoAccess (1<<23) /* Don't access memory (lea/invlpg/verr etc) */ 139 #define Op3264 (1<<24) /* Operand is 64b in long mode, 32b otherwise */ 140 #define Undefined (1<<25) /* No Such Instruction */ 141 #define Lock (1<<26) /* lock prefix is allowed for the instruction */ 142 #define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */ 143 #define No64 (1<<28) 144 #define PageTable (1 << 29) /* instruction used to write page table */ 145 #define NotImpl (1 << 30) /* instruction is not implemented */ 146 /* Source 2 operand type */ 147 #define Src2Shift (31) 148 #define Src2None (OpNone << Src2Shift) 149 #define Src2Mem (OpMem << Src2Shift) 150 #define Src2CL (OpCL << Src2Shift) 151 #define Src2ImmByte (OpImmByte << Src2Shift) 152 #define Src2One (OpOne << Src2Shift) 153 #define Src2Imm (OpImm << Src2Shift) 154 #define Src2ES (OpES << Src2Shift) 155 #define Src2CS (OpCS << Src2Shift) 156 #define Src2SS (OpSS << Src2Shift) 157 #define Src2DS (OpDS << Src2Shift) 158 #define Src2FS (OpFS << Src2Shift) 159 #define Src2GS (OpGS << Src2Shift) 160 #define Src2Mask (OpMask << Src2Shift) 161 #define Mmx ((u64)1 << 40) /* MMX Vector instruction */ 162 #define Aligned ((u64)1 << 41) /* Explicitly aligned (e.g. MOVDQA) */ 163 #define Unaligned ((u64)1 << 42) /* Explicitly unaligned (e.g. MOVDQU) */ 164 #define Avx ((u64)1 << 43) /* Advanced Vector Extensions */ 165 #define Fastop ((u64)1 << 44) /* Use opcode::u.fastop */ 166 #define NoWrite ((u64)1 << 45) /* No writeback */ 167 #define SrcWrite ((u64)1 << 46) /* Write back src operand */ 168 #define NoMod ((u64)1 << 47) /* Mod field is ignored */ 169 #define Intercept ((u64)1 << 48) /* Has valid intercept field */ 170 #define CheckPerm ((u64)1 << 49) /* Has valid check_perm field */ 171 #define PrivUD ((u64)1 << 51) /* #UD instead of #GP on CPL > 0 */ 172 #define NearBranch ((u64)1 << 52) /* Near branches */ 173 #define No16 ((u64)1 << 53) /* No 16 bit operand */ 174 #define IncSP ((u64)1 << 54) /* SP is incremented before ModRM calc */ 175 176 #define DstXacc (DstAccLo | SrcAccHi | SrcWrite) 177 178 #define X2(x...) x, x 179 #define X3(x...) X2(x), x 180 #define X4(x...) X2(x), X2(x) 181 #define X5(x...) X4(x), x 182 #define X6(x...) X4(x), X2(x) 183 #define X7(x...) X4(x), X3(x) 184 #define X8(x...) X4(x), X4(x) 185 #define X16(x...) X8(x), X8(x) 186 187 #define NR_FASTOP (ilog2(sizeof(ulong)) + 1) 188 #define FASTOP_SIZE 8 189 190 /* 191 * fastop functions have a special calling convention: 192 * 193 * dst: rax (in/out) 194 * src: rdx (in/out) 195 * src2: rcx (in) 196 * flags: rflags (in/out) 197 * ex: rsi (in:fastop pointer, out:zero if exception) 198 * 199 * Moreover, they are all exactly FASTOP_SIZE bytes long, so functions for 200 * different operand sizes can be reached by calculation, rather than a jump 201 * table (which would be bigger than the code). 202 * 203 * fastop functions are declared as taking a never-defined fastop parameter, 204 * so they can't be called from C directly. 205 */ 206 207 struct fastop; 208 209 struct opcode { 210 u64 flags : 56; 211 u64 intercept : 8; 212 union { 213 int (*execute)(struct x86_emulate_ctxt *ctxt); 214 const struct opcode *group; 215 const struct group_dual *gdual; 216 const struct gprefix *gprefix; 217 const struct escape *esc; 218 const struct instr_dual *idual; 219 const struct mode_dual *mdual; 220 void (*fastop)(struct fastop *fake); 221 } u; 222 int (*check_perm)(struct x86_emulate_ctxt *ctxt); 223 }; 224 225 struct group_dual { 226 struct opcode mod012[8]; 227 struct opcode mod3[8]; 228 }; 229 230 struct gprefix { 231 struct opcode pfx_no; 232 struct opcode pfx_66; 233 struct opcode pfx_f2; 234 struct opcode pfx_f3; 235 }; 236 237 struct escape { 238 struct opcode op[8]; 239 struct opcode high[64]; 240 }; 241 242 struct instr_dual { 243 struct opcode mod012; 244 struct opcode mod3; 245 }; 246 247 struct mode_dual { 248 struct opcode mode32; 249 struct opcode mode64; 250 }; 251 252 #define EFLG_RESERVED_ZEROS_MASK 0xffc0802a 253 254 enum x86_transfer_type { 255 X86_TRANSFER_NONE, 256 X86_TRANSFER_CALL_JMP, 257 X86_TRANSFER_RET, 258 X86_TRANSFER_TASK_SWITCH, 259 }; 260 261 static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr) 262 { 263 if (!(ctxt->regs_valid & (1 << nr))) { 264 ctxt->regs_valid |= 1 << nr; 265 ctxt->_regs[nr] = ctxt->ops->read_gpr(ctxt, nr); 266 } 267 return ctxt->_regs[nr]; 268 } 269 270 static ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr) 271 { 272 ctxt->regs_valid |= 1 << nr; 273 ctxt->regs_dirty |= 1 << nr; 274 return &ctxt->_regs[nr]; 275 } 276 277 static ulong *reg_rmw(struct x86_emulate_ctxt *ctxt, unsigned nr) 278 { 279 reg_read(ctxt, nr); 280 return reg_write(ctxt, nr); 281 } 282 283 static void writeback_registers(struct x86_emulate_ctxt *ctxt) 284 { 285 unsigned reg; 286 287 for_each_set_bit(reg, (ulong *)&ctxt->regs_dirty, 16) 288 ctxt->ops->write_gpr(ctxt, reg, ctxt->_regs[reg]); 289 } 290 291 static void invalidate_registers(struct x86_emulate_ctxt *ctxt) 292 { 293 ctxt->regs_dirty = 0; 294 ctxt->regs_valid = 0; 295 } 296 297 /* 298 * These EFLAGS bits are restored from saved value during emulation, and 299 * any changes are written back to the saved value after emulation. 300 */ 301 #define EFLAGS_MASK (X86_EFLAGS_OF|X86_EFLAGS_SF|X86_EFLAGS_ZF|X86_EFLAGS_AF|\ 302 X86_EFLAGS_PF|X86_EFLAGS_CF) 303 304 #ifdef CONFIG_X86_64 305 #define ON64(x) x 306 #else 307 #define ON64(x) 308 #endif 309 310 static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); 311 312 #define FOP_FUNC(name) \ 313 ".align " __stringify(FASTOP_SIZE) " \n\t" \ 314 ".type " name ", @function \n\t" \ 315 name ":\n\t" 316 317 #define FOP_RET "ret \n\t" 318 319 #define FOP_START(op) \ 320 extern void em_##op(struct fastop *fake); \ 321 asm(".pushsection .text, \"ax\" \n\t" \ 322 ".global em_" #op " \n\t" \ 323 FOP_FUNC("em_" #op) 324 325 #define FOP_END \ 326 ".popsection") 327 328 #define FOPNOP() \ 329 FOP_FUNC(__stringify(__UNIQUE_ID(nop))) \ 330 FOP_RET 331 332 #define FOP1E(op, dst) \ 333 FOP_FUNC(#op "_" #dst) \ 334 "10: " #op " %" #dst " \n\t" FOP_RET 335 336 #define FOP1EEX(op, dst) \ 337 FOP1E(op, dst) _ASM_EXTABLE(10b, kvm_fastop_exception) 338 339 #define FASTOP1(op) \ 340 FOP_START(op) \ 341 FOP1E(op##b, al) \ 342 FOP1E(op##w, ax) \ 343 FOP1E(op##l, eax) \ 344 ON64(FOP1E(op##q, rax)) \ 345 FOP_END 346 347 /* 1-operand, using src2 (for MUL/DIV r/m) */ 348 #define FASTOP1SRC2(op, name) \ 349 FOP_START(name) \ 350 FOP1E(op, cl) \ 351 FOP1E(op, cx) \ 352 FOP1E(op, ecx) \ 353 ON64(FOP1E(op, rcx)) \ 354 FOP_END 355 356 /* 1-operand, using src2 (for MUL/DIV r/m), with exceptions */ 357 #define FASTOP1SRC2EX(op, name) \ 358 FOP_START(name) \ 359 FOP1EEX(op, cl) \ 360 FOP1EEX(op, cx) \ 361 FOP1EEX(op, ecx) \ 362 ON64(FOP1EEX(op, rcx)) \ 363 FOP_END 364 365 #define FOP2E(op, dst, src) \ 366 FOP_FUNC(#op "_" #dst "_" #src) \ 367 #op " %" #src ", %" #dst " \n\t" FOP_RET 368 369 #define FASTOP2(op) \ 370 FOP_START(op) \ 371 FOP2E(op##b, al, dl) \ 372 FOP2E(op##w, ax, dx) \ 373 FOP2E(op##l, eax, edx) \ 374 ON64(FOP2E(op##q, rax, rdx)) \ 375 FOP_END 376 377 /* 2 operand, word only */ 378 #define FASTOP2W(op) \ 379 FOP_START(op) \ 380 FOPNOP() \ 381 FOP2E(op##w, ax, dx) \ 382 FOP2E(op##l, eax, edx) \ 383 ON64(FOP2E(op##q, rax, rdx)) \ 384 FOP_END 385 386 /* 2 operand, src is CL */ 387 #define FASTOP2CL(op) \ 388 FOP_START(op) \ 389 FOP2E(op##b, al, cl) \ 390 FOP2E(op##w, ax, cl) \ 391 FOP2E(op##l, eax, cl) \ 392 ON64(FOP2E(op##q, rax, cl)) \ 393 FOP_END 394 395 /* 2 operand, src and dest are reversed */ 396 #define FASTOP2R(op, name) \ 397 FOP_START(name) \ 398 FOP2E(op##b, dl, al) \ 399 FOP2E(op##w, dx, ax) \ 400 FOP2E(op##l, edx, eax) \ 401 ON64(FOP2E(op##q, rdx, rax)) \ 402 FOP_END 403 404 #define FOP3E(op, dst, src, src2) \ 405 FOP_FUNC(#op "_" #dst "_" #src "_" #src2) \ 406 #op " %" #src2 ", %" #src ", %" #dst " \n\t" FOP_RET 407 408 /* 3-operand, word-only, src2=cl */ 409 #define FASTOP3WCL(op) \ 410 FOP_START(op) \ 411 FOPNOP() \ 412 FOP3E(op##w, ax, dx, cl) \ 413 FOP3E(op##l, eax, edx, cl) \ 414 ON64(FOP3E(op##q, rax, rdx, cl)) \ 415 FOP_END 416 417 /* Special case for SETcc - 1 instruction per cc */ 418 #define FOP_SETCC(op) \ 419 ".align 4 \n\t" \ 420 ".type " #op ", @function \n\t" \ 421 #op ": \n\t" \ 422 #op " %al \n\t" \ 423 FOP_RET 424 425 asm(".global kvm_fastop_exception \n" 426 "kvm_fastop_exception: xor %esi, %esi; ret"); 427 428 FOP_START(setcc) 429 FOP_SETCC(seto) 430 FOP_SETCC(setno) 431 FOP_SETCC(setc) 432 FOP_SETCC(setnc) 433 FOP_SETCC(setz) 434 FOP_SETCC(setnz) 435 FOP_SETCC(setbe) 436 FOP_SETCC(setnbe) 437 FOP_SETCC(sets) 438 FOP_SETCC(setns) 439 FOP_SETCC(setp) 440 FOP_SETCC(setnp) 441 FOP_SETCC(setl) 442 FOP_SETCC(setnl) 443 FOP_SETCC(setle) 444 FOP_SETCC(setnle) 445 FOP_END; 446 447 FOP_START(salc) "pushf; sbb %al, %al; popf \n\t" FOP_RET 448 FOP_END; 449 450 static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt, 451 enum x86_intercept intercept, 452 enum x86_intercept_stage stage) 453 { 454 struct x86_instruction_info info = { 455 .intercept = intercept, 456 .rep_prefix = ctxt->rep_prefix, 457 .modrm_mod = ctxt->modrm_mod, 458 .modrm_reg = ctxt->modrm_reg, 459 .modrm_rm = ctxt->modrm_rm, 460 .src_val = ctxt->src.val64, 461 .dst_val = ctxt->dst.val64, 462 .src_bytes = ctxt->src.bytes, 463 .dst_bytes = ctxt->dst.bytes, 464 .ad_bytes = ctxt->ad_bytes, 465 .next_rip = ctxt->eip, 466 }; 467 468 return ctxt->ops->intercept(ctxt, &info, stage); 469 } 470 471 static void assign_masked(ulong *dest, ulong src, ulong mask) 472 { 473 *dest = (*dest & ~mask) | (src & mask); 474 } 475 476 static void assign_register(unsigned long *reg, u64 val, int bytes) 477 { 478 /* The 4-byte case *is* correct: in 64-bit mode we zero-extend. */ 479 switch (bytes) { 480 case 1: 481 *(u8 *)reg = (u8)val; 482 break; 483 case 2: 484 *(u16 *)reg = (u16)val; 485 break; 486 case 4: 487 *reg = (u32)val; 488 break; /* 64b: zero-extend */ 489 case 8: 490 *reg = val; 491 break; 492 } 493 } 494 495 static inline unsigned long ad_mask(struct x86_emulate_ctxt *ctxt) 496 { 497 return (1UL << (ctxt->ad_bytes << 3)) - 1; 498 } 499 500 static ulong stack_mask(struct x86_emulate_ctxt *ctxt) 501 { 502 u16 sel; 503 struct desc_struct ss; 504 505 if (ctxt->mode == X86EMUL_MODE_PROT64) 506 return ~0UL; 507 ctxt->ops->get_segment(ctxt, &sel, &ss, NULL, VCPU_SREG_SS); 508 return ~0U >> ((ss.d ^ 1) * 16); /* d=0: 0xffff; d=1: 0xffffffff */ 509 } 510 511 static int stack_size(struct x86_emulate_ctxt *ctxt) 512 { 513 return (__fls(stack_mask(ctxt)) + 1) >> 3; 514 } 515 516 /* Access/update address held in a register, based on addressing mode. */ 517 static inline unsigned long 518 address_mask(struct x86_emulate_ctxt *ctxt, unsigned long reg) 519 { 520 if (ctxt->ad_bytes == sizeof(unsigned long)) 521 return reg; 522 else 523 return reg & ad_mask(ctxt); 524 } 525 526 static inline unsigned long 527 register_address(struct x86_emulate_ctxt *ctxt, int reg) 528 { 529 return address_mask(ctxt, reg_read(ctxt, reg)); 530 } 531 532 static void masked_increment(ulong *reg, ulong mask, int inc) 533 { 534 assign_masked(reg, *reg + inc, mask); 535 } 536 537 static inline void 538 register_address_increment(struct x86_emulate_ctxt *ctxt, int reg, int inc) 539 { 540 ulong *preg = reg_rmw(ctxt, reg); 541 542 assign_register(preg, *preg + inc, ctxt->ad_bytes); 543 } 544 545 static void rsp_increment(struct x86_emulate_ctxt *ctxt, int inc) 546 { 547 masked_increment(reg_rmw(ctxt, VCPU_REGS_RSP), stack_mask(ctxt), inc); 548 } 549 550 static u32 desc_limit_scaled(struct desc_struct *desc) 551 { 552 u32 limit = get_desc_limit(desc); 553 554 return desc->g ? (limit << 12) | 0xfff : limit; 555 } 556 557 static unsigned long seg_base(struct x86_emulate_ctxt *ctxt, int seg) 558 { 559 if (ctxt->mode == X86EMUL_MODE_PROT64 && seg < VCPU_SREG_FS) 560 return 0; 561 562 return ctxt->ops->get_cached_segment_base(ctxt, seg); 563 } 564 565 static int emulate_exception(struct x86_emulate_ctxt *ctxt, int vec, 566 u32 error, bool valid) 567 { 568 WARN_ON(vec > 0x1f); 569 ctxt->exception.vector = vec; 570 ctxt->exception.error_code = error; 571 ctxt->exception.error_code_valid = valid; 572 return X86EMUL_PROPAGATE_FAULT; 573 } 574 575 static int emulate_db(struct x86_emulate_ctxt *ctxt) 576 { 577 return emulate_exception(ctxt, DB_VECTOR, 0, false); 578 } 579 580 static int emulate_gp(struct x86_emulate_ctxt *ctxt, int err) 581 { 582 return emulate_exception(ctxt, GP_VECTOR, err, true); 583 } 584 585 static int emulate_ss(struct x86_emulate_ctxt *ctxt, int err) 586 { 587 return emulate_exception(ctxt, SS_VECTOR, err, true); 588 } 589 590 static int emulate_ud(struct x86_emulate_ctxt *ctxt) 591 { 592 return emulate_exception(ctxt, UD_VECTOR, 0, false); 593 } 594 595 static int emulate_ts(struct x86_emulate_ctxt *ctxt, int err) 596 { 597 return emulate_exception(ctxt, TS_VECTOR, err, true); 598 } 599 600 static int emulate_de(struct x86_emulate_ctxt *ctxt) 601 { 602 return emulate_exception(ctxt, DE_VECTOR, 0, false); 603 } 604 605 static int emulate_nm(struct x86_emulate_ctxt *ctxt) 606 { 607 return emulate_exception(ctxt, NM_VECTOR, 0, false); 608 } 609 610 static u16 get_segment_selector(struct x86_emulate_ctxt *ctxt, unsigned seg) 611 { 612 u16 selector; 613 struct desc_struct desc; 614 615 ctxt->ops->get_segment(ctxt, &selector, &desc, NULL, seg); 616 return selector; 617 } 618 619 static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector, 620 unsigned seg) 621 { 622 u16 dummy; 623 u32 base3; 624 struct desc_struct desc; 625 626 ctxt->ops->get_segment(ctxt, &dummy, &desc, &base3, seg); 627 ctxt->ops->set_segment(ctxt, selector, &desc, base3, seg); 628 } 629 630 /* 631 * x86 defines three classes of vector instructions: explicitly 632 * aligned, explicitly unaligned, and the rest, which change behaviour 633 * depending on whether they're AVX encoded or not. 634 * 635 * Also included is CMPXCHG16B which is not a vector instruction, yet it is 636 * subject to the same check. 637 */ 638 static bool insn_aligned(struct x86_emulate_ctxt *ctxt, unsigned size) 639 { 640 if (likely(size < 16)) 641 return false; 642 643 if (ctxt->d & Aligned) 644 return true; 645 else if (ctxt->d & Unaligned) 646 return false; 647 else if (ctxt->d & Avx) 648 return false; 649 else 650 return true; 651 } 652 653 static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt, 654 struct segmented_address addr, 655 unsigned *max_size, unsigned size, 656 bool write, bool fetch, 657 enum x86emul_mode mode, ulong *linear) 658 { 659 struct desc_struct desc; 660 bool usable; 661 ulong la; 662 u32 lim; 663 u16 sel; 664 665 la = seg_base(ctxt, addr.seg) + addr.ea; 666 *max_size = 0; 667 switch (mode) { 668 case X86EMUL_MODE_PROT64: 669 *linear = la; 670 if (is_noncanonical_address(la)) 671 goto bad; 672 673 *max_size = min_t(u64, ~0u, (1ull << 48) - la); 674 if (size > *max_size) 675 goto bad; 676 break; 677 default: 678 *linear = la = (u32)la; 679 usable = ctxt->ops->get_segment(ctxt, &sel, &desc, NULL, 680 addr.seg); 681 if (!usable) 682 goto bad; 683 /* code segment in protected mode or read-only data segment */ 684 if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8)) 685 || !(desc.type & 2)) && write) 686 goto bad; 687 /* unreadable code segment */ 688 if (!fetch && (desc.type & 8) && !(desc.type & 2)) 689 goto bad; 690 lim = desc_limit_scaled(&desc); 691 if (!(desc.type & 8) && (desc.type & 4)) { 692 /* expand-down segment */ 693 if (addr.ea <= lim) 694 goto bad; 695 lim = desc.d ? 0xffffffff : 0xffff; 696 } 697 if (addr.ea > lim) 698 goto bad; 699 if (lim == 0xffffffff) 700 *max_size = ~0u; 701 else { 702 *max_size = (u64)lim + 1 - addr.ea; 703 if (size > *max_size) 704 goto bad; 705 } 706 break; 707 } 708 if (insn_aligned(ctxt, size) && ((la & (size - 1)) != 0)) 709 return emulate_gp(ctxt, 0); 710 return X86EMUL_CONTINUE; 711 bad: 712 if (addr.seg == VCPU_SREG_SS) 713 return emulate_ss(ctxt, 0); 714 else 715 return emulate_gp(ctxt, 0); 716 } 717 718 static int linearize(struct x86_emulate_ctxt *ctxt, 719 struct segmented_address addr, 720 unsigned size, bool write, 721 ulong *linear) 722 { 723 unsigned max_size; 724 return __linearize(ctxt, addr, &max_size, size, write, false, 725 ctxt->mode, linear); 726 } 727 728 static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst, 729 enum x86emul_mode mode) 730 { 731 ulong linear; 732 int rc; 733 unsigned max_size; 734 struct segmented_address addr = { .seg = VCPU_SREG_CS, 735 .ea = dst }; 736 737 if (ctxt->op_bytes != sizeof(unsigned long)) 738 addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1); 739 rc = __linearize(ctxt, addr, &max_size, 1, false, true, mode, &linear); 740 if (rc == X86EMUL_CONTINUE) 741 ctxt->_eip = addr.ea; 742 return rc; 743 } 744 745 static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst) 746 { 747 return assign_eip(ctxt, dst, ctxt->mode); 748 } 749 750 static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst, 751 const struct desc_struct *cs_desc) 752 { 753 enum x86emul_mode mode = ctxt->mode; 754 int rc; 755 756 #ifdef CONFIG_X86_64 757 if (ctxt->mode >= X86EMUL_MODE_PROT16) { 758 if (cs_desc->l) { 759 u64 efer = 0; 760 761 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 762 if (efer & EFER_LMA) 763 mode = X86EMUL_MODE_PROT64; 764 } else 765 mode = X86EMUL_MODE_PROT32; /* temporary value */ 766 } 767 #endif 768 if (mode == X86EMUL_MODE_PROT16 || mode == X86EMUL_MODE_PROT32) 769 mode = cs_desc->d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16; 770 rc = assign_eip(ctxt, dst, mode); 771 if (rc == X86EMUL_CONTINUE) 772 ctxt->mode = mode; 773 return rc; 774 } 775 776 static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel) 777 { 778 return assign_eip_near(ctxt, ctxt->_eip + rel); 779 } 780 781 static int segmented_read_std(struct x86_emulate_ctxt *ctxt, 782 struct segmented_address addr, 783 void *data, 784 unsigned size) 785 { 786 int rc; 787 ulong linear; 788 789 rc = linearize(ctxt, addr, size, false, &linear); 790 if (rc != X86EMUL_CONTINUE) 791 return rc; 792 return ctxt->ops->read_std(ctxt, linear, data, size, &ctxt->exception); 793 } 794 795 /* 796 * Prefetch the remaining bytes of the instruction without crossing page 797 * boundary if they are not in fetch_cache yet. 798 */ 799 static int __do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt, int op_size) 800 { 801 int rc; 802 unsigned size, max_size; 803 unsigned long linear; 804 int cur_size = ctxt->fetch.end - ctxt->fetch.data; 805 struct segmented_address addr = { .seg = VCPU_SREG_CS, 806 .ea = ctxt->eip + cur_size }; 807 808 /* 809 * We do not know exactly how many bytes will be needed, and 810 * __linearize is expensive, so fetch as much as possible. We 811 * just have to avoid going beyond the 15 byte limit, the end 812 * of the segment, or the end of the page. 813 * 814 * __linearize is called with size 0 so that it does not do any 815 * boundary check itself. Instead, we use max_size to check 816 * against op_size. 817 */ 818 rc = __linearize(ctxt, addr, &max_size, 0, false, true, ctxt->mode, 819 &linear); 820 if (unlikely(rc != X86EMUL_CONTINUE)) 821 return rc; 822 823 size = min_t(unsigned, 15UL ^ cur_size, max_size); 824 size = min_t(unsigned, size, PAGE_SIZE - offset_in_page(linear)); 825 826 /* 827 * One instruction can only straddle two pages, 828 * and one has been loaded at the beginning of 829 * x86_decode_insn. So, if not enough bytes 830 * still, we must have hit the 15-byte boundary. 831 */ 832 if (unlikely(size < op_size)) 833 return emulate_gp(ctxt, 0); 834 835 rc = ctxt->ops->fetch(ctxt, linear, ctxt->fetch.end, 836 size, &ctxt->exception); 837 if (unlikely(rc != X86EMUL_CONTINUE)) 838 return rc; 839 ctxt->fetch.end += size; 840 return X86EMUL_CONTINUE; 841 } 842 843 static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt, 844 unsigned size) 845 { 846 unsigned done_size = ctxt->fetch.end - ctxt->fetch.ptr; 847 848 if (unlikely(done_size < size)) 849 return __do_insn_fetch_bytes(ctxt, size - done_size); 850 else 851 return X86EMUL_CONTINUE; 852 } 853 854 /* Fetch next part of the instruction being emulated. */ 855 #define insn_fetch(_type, _ctxt) \ 856 ({ _type _x; \ 857 \ 858 rc = do_insn_fetch_bytes(_ctxt, sizeof(_type)); \ 859 if (rc != X86EMUL_CONTINUE) \ 860 goto done; \ 861 ctxt->_eip += sizeof(_type); \ 862 _x = *(_type __aligned(1) *) ctxt->fetch.ptr; \ 863 ctxt->fetch.ptr += sizeof(_type); \ 864 _x; \ 865 }) 866 867 #define insn_fetch_arr(_arr, _size, _ctxt) \ 868 ({ \ 869 rc = do_insn_fetch_bytes(_ctxt, _size); \ 870 if (rc != X86EMUL_CONTINUE) \ 871 goto done; \ 872 ctxt->_eip += (_size); \ 873 memcpy(_arr, ctxt->fetch.ptr, _size); \ 874 ctxt->fetch.ptr += (_size); \ 875 }) 876 877 /* 878 * Given the 'reg' portion of a ModRM byte, and a register block, return a 879 * pointer into the block that addresses the relevant register. 880 * @highbyte_regs specifies whether to decode AH,CH,DH,BH. 881 */ 882 static void *decode_register(struct x86_emulate_ctxt *ctxt, u8 modrm_reg, 883 int byteop) 884 { 885 void *p; 886 int highbyte_regs = (ctxt->rex_prefix == 0) && byteop; 887 888 if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8) 889 p = (unsigned char *)reg_rmw(ctxt, modrm_reg & 3) + 1; 890 else 891 p = reg_rmw(ctxt, modrm_reg); 892 return p; 893 } 894 895 static int read_descriptor(struct x86_emulate_ctxt *ctxt, 896 struct segmented_address addr, 897 u16 *size, unsigned long *address, int op_bytes) 898 { 899 int rc; 900 901 if (op_bytes == 2) 902 op_bytes = 3; 903 *address = 0; 904 rc = segmented_read_std(ctxt, addr, size, 2); 905 if (rc != X86EMUL_CONTINUE) 906 return rc; 907 addr.ea += 2; 908 rc = segmented_read_std(ctxt, addr, address, op_bytes); 909 return rc; 910 } 911 912 FASTOP2(add); 913 FASTOP2(or); 914 FASTOP2(adc); 915 FASTOP2(sbb); 916 FASTOP2(and); 917 FASTOP2(sub); 918 FASTOP2(xor); 919 FASTOP2(cmp); 920 FASTOP2(test); 921 922 FASTOP1SRC2(mul, mul_ex); 923 FASTOP1SRC2(imul, imul_ex); 924 FASTOP1SRC2EX(div, div_ex); 925 FASTOP1SRC2EX(idiv, idiv_ex); 926 927 FASTOP3WCL(shld); 928 FASTOP3WCL(shrd); 929 930 FASTOP2W(imul); 931 932 FASTOP1(not); 933 FASTOP1(neg); 934 FASTOP1(inc); 935 FASTOP1(dec); 936 937 FASTOP2CL(rol); 938 FASTOP2CL(ror); 939 FASTOP2CL(rcl); 940 FASTOP2CL(rcr); 941 FASTOP2CL(shl); 942 FASTOP2CL(shr); 943 FASTOP2CL(sar); 944 945 FASTOP2W(bsf); 946 FASTOP2W(bsr); 947 FASTOP2W(bt); 948 FASTOP2W(bts); 949 FASTOP2W(btr); 950 FASTOP2W(btc); 951 952 FASTOP2(xadd); 953 954 FASTOP2R(cmp, cmp_r); 955 956 static int em_bsf_c(struct x86_emulate_ctxt *ctxt) 957 { 958 /* If src is zero, do not writeback, but update flags */ 959 if (ctxt->src.val == 0) 960 ctxt->dst.type = OP_NONE; 961 return fastop(ctxt, em_bsf); 962 } 963 964 static int em_bsr_c(struct x86_emulate_ctxt *ctxt) 965 { 966 /* If src is zero, do not writeback, but update flags */ 967 if (ctxt->src.val == 0) 968 ctxt->dst.type = OP_NONE; 969 return fastop(ctxt, em_bsr); 970 } 971 972 static __always_inline u8 test_cc(unsigned int condition, unsigned long flags) 973 { 974 u8 rc; 975 void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf); 976 977 flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF; 978 asm("push %[flags]; popf; call *%[fastop]" 979 : "=a"(rc) : [fastop]"r"(fop), [flags]"r"(flags)); 980 return rc; 981 } 982 983 static void fetch_register_operand(struct operand *op) 984 { 985 switch (op->bytes) { 986 case 1: 987 op->val = *(u8 *)op->addr.reg; 988 break; 989 case 2: 990 op->val = *(u16 *)op->addr.reg; 991 break; 992 case 4: 993 op->val = *(u32 *)op->addr.reg; 994 break; 995 case 8: 996 op->val = *(u64 *)op->addr.reg; 997 break; 998 } 999 } 1000 1001 static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg) 1002 { 1003 ctxt->ops->get_fpu(ctxt); 1004 switch (reg) { 1005 case 0: asm("movdqa %%xmm0, %0" : "=m"(*data)); break; 1006 case 1: asm("movdqa %%xmm1, %0" : "=m"(*data)); break; 1007 case 2: asm("movdqa %%xmm2, %0" : "=m"(*data)); break; 1008 case 3: asm("movdqa %%xmm3, %0" : "=m"(*data)); break; 1009 case 4: asm("movdqa %%xmm4, %0" : "=m"(*data)); break; 1010 case 5: asm("movdqa %%xmm5, %0" : "=m"(*data)); break; 1011 case 6: asm("movdqa %%xmm6, %0" : "=m"(*data)); break; 1012 case 7: asm("movdqa %%xmm7, %0" : "=m"(*data)); break; 1013 #ifdef CONFIG_X86_64 1014 case 8: asm("movdqa %%xmm8, %0" : "=m"(*data)); break; 1015 case 9: asm("movdqa %%xmm9, %0" : "=m"(*data)); break; 1016 case 10: asm("movdqa %%xmm10, %0" : "=m"(*data)); break; 1017 case 11: asm("movdqa %%xmm11, %0" : "=m"(*data)); break; 1018 case 12: asm("movdqa %%xmm12, %0" : "=m"(*data)); break; 1019 case 13: asm("movdqa %%xmm13, %0" : "=m"(*data)); break; 1020 case 14: asm("movdqa %%xmm14, %0" : "=m"(*data)); break; 1021 case 15: asm("movdqa %%xmm15, %0" : "=m"(*data)); break; 1022 #endif 1023 default: BUG(); 1024 } 1025 ctxt->ops->put_fpu(ctxt); 1026 } 1027 1028 static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, 1029 int reg) 1030 { 1031 ctxt->ops->get_fpu(ctxt); 1032 switch (reg) { 1033 case 0: asm("movdqa %0, %%xmm0" : : "m"(*data)); break; 1034 case 1: asm("movdqa %0, %%xmm1" : : "m"(*data)); break; 1035 case 2: asm("movdqa %0, %%xmm2" : : "m"(*data)); break; 1036 case 3: asm("movdqa %0, %%xmm3" : : "m"(*data)); break; 1037 case 4: asm("movdqa %0, %%xmm4" : : "m"(*data)); break; 1038 case 5: asm("movdqa %0, %%xmm5" : : "m"(*data)); break; 1039 case 6: asm("movdqa %0, %%xmm6" : : "m"(*data)); break; 1040 case 7: asm("movdqa %0, %%xmm7" : : "m"(*data)); break; 1041 #ifdef CONFIG_X86_64 1042 case 8: asm("movdqa %0, %%xmm8" : : "m"(*data)); break; 1043 case 9: asm("movdqa %0, %%xmm9" : : "m"(*data)); break; 1044 case 10: asm("movdqa %0, %%xmm10" : : "m"(*data)); break; 1045 case 11: asm("movdqa %0, %%xmm11" : : "m"(*data)); break; 1046 case 12: asm("movdqa %0, %%xmm12" : : "m"(*data)); break; 1047 case 13: asm("movdqa %0, %%xmm13" : : "m"(*data)); break; 1048 case 14: asm("movdqa %0, %%xmm14" : : "m"(*data)); break; 1049 case 15: asm("movdqa %0, %%xmm15" : : "m"(*data)); break; 1050 #endif 1051 default: BUG(); 1052 } 1053 ctxt->ops->put_fpu(ctxt); 1054 } 1055 1056 static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg) 1057 { 1058 ctxt->ops->get_fpu(ctxt); 1059 switch (reg) { 1060 case 0: asm("movq %%mm0, %0" : "=m"(*data)); break; 1061 case 1: asm("movq %%mm1, %0" : "=m"(*data)); break; 1062 case 2: asm("movq %%mm2, %0" : "=m"(*data)); break; 1063 case 3: asm("movq %%mm3, %0" : "=m"(*data)); break; 1064 case 4: asm("movq %%mm4, %0" : "=m"(*data)); break; 1065 case 5: asm("movq %%mm5, %0" : "=m"(*data)); break; 1066 case 6: asm("movq %%mm6, %0" : "=m"(*data)); break; 1067 case 7: asm("movq %%mm7, %0" : "=m"(*data)); break; 1068 default: BUG(); 1069 } 1070 ctxt->ops->put_fpu(ctxt); 1071 } 1072 1073 static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg) 1074 { 1075 ctxt->ops->get_fpu(ctxt); 1076 switch (reg) { 1077 case 0: asm("movq %0, %%mm0" : : "m"(*data)); break; 1078 case 1: asm("movq %0, %%mm1" : : "m"(*data)); break; 1079 case 2: asm("movq %0, %%mm2" : : "m"(*data)); break; 1080 case 3: asm("movq %0, %%mm3" : : "m"(*data)); break; 1081 case 4: asm("movq %0, %%mm4" : : "m"(*data)); break; 1082 case 5: asm("movq %0, %%mm5" : : "m"(*data)); break; 1083 case 6: asm("movq %0, %%mm6" : : "m"(*data)); break; 1084 case 7: asm("movq %0, %%mm7" : : "m"(*data)); break; 1085 default: BUG(); 1086 } 1087 ctxt->ops->put_fpu(ctxt); 1088 } 1089 1090 static int em_fninit(struct x86_emulate_ctxt *ctxt) 1091 { 1092 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM)) 1093 return emulate_nm(ctxt); 1094 1095 ctxt->ops->get_fpu(ctxt); 1096 asm volatile("fninit"); 1097 ctxt->ops->put_fpu(ctxt); 1098 return X86EMUL_CONTINUE; 1099 } 1100 1101 static int em_fnstcw(struct x86_emulate_ctxt *ctxt) 1102 { 1103 u16 fcw; 1104 1105 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM)) 1106 return emulate_nm(ctxt); 1107 1108 ctxt->ops->get_fpu(ctxt); 1109 asm volatile("fnstcw %0": "+m"(fcw)); 1110 ctxt->ops->put_fpu(ctxt); 1111 1112 ctxt->dst.val = fcw; 1113 1114 return X86EMUL_CONTINUE; 1115 } 1116 1117 static int em_fnstsw(struct x86_emulate_ctxt *ctxt) 1118 { 1119 u16 fsw; 1120 1121 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM)) 1122 return emulate_nm(ctxt); 1123 1124 ctxt->ops->get_fpu(ctxt); 1125 asm volatile("fnstsw %0": "+m"(fsw)); 1126 ctxt->ops->put_fpu(ctxt); 1127 1128 ctxt->dst.val = fsw; 1129 1130 return X86EMUL_CONTINUE; 1131 } 1132 1133 static void decode_register_operand(struct x86_emulate_ctxt *ctxt, 1134 struct operand *op) 1135 { 1136 unsigned reg = ctxt->modrm_reg; 1137 1138 if (!(ctxt->d & ModRM)) 1139 reg = (ctxt->b & 7) | ((ctxt->rex_prefix & 1) << 3); 1140 1141 if (ctxt->d & Sse) { 1142 op->type = OP_XMM; 1143 op->bytes = 16; 1144 op->addr.xmm = reg; 1145 read_sse_reg(ctxt, &op->vec_val, reg); 1146 return; 1147 } 1148 if (ctxt->d & Mmx) { 1149 reg &= 7; 1150 op->type = OP_MM; 1151 op->bytes = 8; 1152 op->addr.mm = reg; 1153 return; 1154 } 1155 1156 op->type = OP_REG; 1157 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 1158 op->addr.reg = decode_register(ctxt, reg, ctxt->d & ByteOp); 1159 1160 fetch_register_operand(op); 1161 op->orig_val = op->val; 1162 } 1163 1164 static void adjust_modrm_seg(struct x86_emulate_ctxt *ctxt, int base_reg) 1165 { 1166 if (base_reg == VCPU_REGS_RSP || base_reg == VCPU_REGS_RBP) 1167 ctxt->modrm_seg = VCPU_SREG_SS; 1168 } 1169 1170 static int decode_modrm(struct x86_emulate_ctxt *ctxt, 1171 struct operand *op) 1172 { 1173 u8 sib; 1174 int index_reg, base_reg, scale; 1175 int rc = X86EMUL_CONTINUE; 1176 ulong modrm_ea = 0; 1177 1178 ctxt->modrm_reg = ((ctxt->rex_prefix << 1) & 8); /* REX.R */ 1179 index_reg = (ctxt->rex_prefix << 2) & 8; /* REX.X */ 1180 base_reg = (ctxt->rex_prefix << 3) & 8; /* REX.B */ 1181 1182 ctxt->modrm_mod = (ctxt->modrm & 0xc0) >> 6; 1183 ctxt->modrm_reg |= (ctxt->modrm & 0x38) >> 3; 1184 ctxt->modrm_rm = base_reg | (ctxt->modrm & 0x07); 1185 ctxt->modrm_seg = VCPU_SREG_DS; 1186 1187 if (ctxt->modrm_mod == 3 || (ctxt->d & NoMod)) { 1188 op->type = OP_REG; 1189 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 1190 op->addr.reg = decode_register(ctxt, ctxt->modrm_rm, 1191 ctxt->d & ByteOp); 1192 if (ctxt->d & Sse) { 1193 op->type = OP_XMM; 1194 op->bytes = 16; 1195 op->addr.xmm = ctxt->modrm_rm; 1196 read_sse_reg(ctxt, &op->vec_val, ctxt->modrm_rm); 1197 return rc; 1198 } 1199 if (ctxt->d & Mmx) { 1200 op->type = OP_MM; 1201 op->bytes = 8; 1202 op->addr.mm = ctxt->modrm_rm & 7; 1203 return rc; 1204 } 1205 fetch_register_operand(op); 1206 return rc; 1207 } 1208 1209 op->type = OP_MEM; 1210 1211 if (ctxt->ad_bytes == 2) { 1212 unsigned bx = reg_read(ctxt, VCPU_REGS_RBX); 1213 unsigned bp = reg_read(ctxt, VCPU_REGS_RBP); 1214 unsigned si = reg_read(ctxt, VCPU_REGS_RSI); 1215 unsigned di = reg_read(ctxt, VCPU_REGS_RDI); 1216 1217 /* 16-bit ModR/M decode. */ 1218 switch (ctxt->modrm_mod) { 1219 case 0: 1220 if (ctxt->modrm_rm == 6) 1221 modrm_ea += insn_fetch(u16, ctxt); 1222 break; 1223 case 1: 1224 modrm_ea += insn_fetch(s8, ctxt); 1225 break; 1226 case 2: 1227 modrm_ea += insn_fetch(u16, ctxt); 1228 break; 1229 } 1230 switch (ctxt->modrm_rm) { 1231 case 0: 1232 modrm_ea += bx + si; 1233 break; 1234 case 1: 1235 modrm_ea += bx + di; 1236 break; 1237 case 2: 1238 modrm_ea += bp + si; 1239 break; 1240 case 3: 1241 modrm_ea += bp + di; 1242 break; 1243 case 4: 1244 modrm_ea += si; 1245 break; 1246 case 5: 1247 modrm_ea += di; 1248 break; 1249 case 6: 1250 if (ctxt->modrm_mod != 0) 1251 modrm_ea += bp; 1252 break; 1253 case 7: 1254 modrm_ea += bx; 1255 break; 1256 } 1257 if (ctxt->modrm_rm == 2 || ctxt->modrm_rm == 3 || 1258 (ctxt->modrm_rm == 6 && ctxt->modrm_mod != 0)) 1259 ctxt->modrm_seg = VCPU_SREG_SS; 1260 modrm_ea = (u16)modrm_ea; 1261 } else { 1262 /* 32/64-bit ModR/M decode. */ 1263 if ((ctxt->modrm_rm & 7) == 4) { 1264 sib = insn_fetch(u8, ctxt); 1265 index_reg |= (sib >> 3) & 7; 1266 base_reg |= sib & 7; 1267 scale = sib >> 6; 1268 1269 if ((base_reg & 7) == 5 && ctxt->modrm_mod == 0) 1270 modrm_ea += insn_fetch(s32, ctxt); 1271 else { 1272 modrm_ea += reg_read(ctxt, base_reg); 1273 adjust_modrm_seg(ctxt, base_reg); 1274 /* Increment ESP on POP [ESP] */ 1275 if ((ctxt->d & IncSP) && 1276 base_reg == VCPU_REGS_RSP) 1277 modrm_ea += ctxt->op_bytes; 1278 } 1279 if (index_reg != 4) 1280 modrm_ea += reg_read(ctxt, index_reg) << scale; 1281 } else if ((ctxt->modrm_rm & 7) == 5 && ctxt->modrm_mod == 0) { 1282 modrm_ea += insn_fetch(s32, ctxt); 1283 if (ctxt->mode == X86EMUL_MODE_PROT64) 1284 ctxt->rip_relative = 1; 1285 } else { 1286 base_reg = ctxt->modrm_rm; 1287 modrm_ea += reg_read(ctxt, base_reg); 1288 adjust_modrm_seg(ctxt, base_reg); 1289 } 1290 switch (ctxt->modrm_mod) { 1291 case 1: 1292 modrm_ea += insn_fetch(s8, ctxt); 1293 break; 1294 case 2: 1295 modrm_ea += insn_fetch(s32, ctxt); 1296 break; 1297 } 1298 } 1299 op->addr.mem.ea = modrm_ea; 1300 if (ctxt->ad_bytes != 8) 1301 ctxt->memop.addr.mem.ea = (u32)ctxt->memop.addr.mem.ea; 1302 1303 done: 1304 return rc; 1305 } 1306 1307 static int decode_abs(struct x86_emulate_ctxt *ctxt, 1308 struct operand *op) 1309 { 1310 int rc = X86EMUL_CONTINUE; 1311 1312 op->type = OP_MEM; 1313 switch (ctxt->ad_bytes) { 1314 case 2: 1315 op->addr.mem.ea = insn_fetch(u16, ctxt); 1316 break; 1317 case 4: 1318 op->addr.mem.ea = insn_fetch(u32, ctxt); 1319 break; 1320 case 8: 1321 op->addr.mem.ea = insn_fetch(u64, ctxt); 1322 break; 1323 } 1324 done: 1325 return rc; 1326 } 1327 1328 static void fetch_bit_operand(struct x86_emulate_ctxt *ctxt) 1329 { 1330 long sv = 0, mask; 1331 1332 if (ctxt->dst.type == OP_MEM && ctxt->src.type == OP_REG) { 1333 mask = ~((long)ctxt->dst.bytes * 8 - 1); 1334 1335 if (ctxt->src.bytes == 2) 1336 sv = (s16)ctxt->src.val & (s16)mask; 1337 else if (ctxt->src.bytes == 4) 1338 sv = (s32)ctxt->src.val & (s32)mask; 1339 else 1340 sv = (s64)ctxt->src.val & (s64)mask; 1341 1342 ctxt->dst.addr.mem.ea = address_mask(ctxt, 1343 ctxt->dst.addr.mem.ea + (sv >> 3)); 1344 } 1345 1346 /* only subword offset */ 1347 ctxt->src.val &= (ctxt->dst.bytes << 3) - 1; 1348 } 1349 1350 static int read_emulated(struct x86_emulate_ctxt *ctxt, 1351 unsigned long addr, void *dest, unsigned size) 1352 { 1353 int rc; 1354 struct read_cache *mc = &ctxt->mem_read; 1355 1356 if (mc->pos < mc->end) 1357 goto read_cached; 1358 1359 WARN_ON((mc->end + size) >= sizeof(mc->data)); 1360 1361 rc = ctxt->ops->read_emulated(ctxt, addr, mc->data + mc->end, size, 1362 &ctxt->exception); 1363 if (rc != X86EMUL_CONTINUE) 1364 return rc; 1365 1366 mc->end += size; 1367 1368 read_cached: 1369 memcpy(dest, mc->data + mc->pos, size); 1370 mc->pos += size; 1371 return X86EMUL_CONTINUE; 1372 } 1373 1374 static int segmented_read(struct x86_emulate_ctxt *ctxt, 1375 struct segmented_address addr, 1376 void *data, 1377 unsigned size) 1378 { 1379 int rc; 1380 ulong linear; 1381 1382 rc = linearize(ctxt, addr, size, false, &linear); 1383 if (rc != X86EMUL_CONTINUE) 1384 return rc; 1385 return read_emulated(ctxt, linear, data, size); 1386 } 1387 1388 static int segmented_write(struct x86_emulate_ctxt *ctxt, 1389 struct segmented_address addr, 1390 const void *data, 1391 unsigned size) 1392 { 1393 int rc; 1394 ulong linear; 1395 1396 rc = linearize(ctxt, addr, size, true, &linear); 1397 if (rc != X86EMUL_CONTINUE) 1398 return rc; 1399 return ctxt->ops->write_emulated(ctxt, linear, data, size, 1400 &ctxt->exception); 1401 } 1402 1403 static int segmented_cmpxchg(struct x86_emulate_ctxt *ctxt, 1404 struct segmented_address addr, 1405 const void *orig_data, const void *data, 1406 unsigned size) 1407 { 1408 int rc; 1409 ulong linear; 1410 1411 rc = linearize(ctxt, addr, size, true, &linear); 1412 if (rc != X86EMUL_CONTINUE) 1413 return rc; 1414 return ctxt->ops->cmpxchg_emulated(ctxt, linear, orig_data, data, 1415 size, &ctxt->exception); 1416 } 1417 1418 static int pio_in_emulated(struct x86_emulate_ctxt *ctxt, 1419 unsigned int size, unsigned short port, 1420 void *dest) 1421 { 1422 struct read_cache *rc = &ctxt->io_read; 1423 1424 if (rc->pos == rc->end) { /* refill pio read ahead */ 1425 unsigned int in_page, n; 1426 unsigned int count = ctxt->rep_prefix ? 1427 address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) : 1; 1428 in_page = (ctxt->eflags & X86_EFLAGS_DF) ? 1429 offset_in_page(reg_read(ctxt, VCPU_REGS_RDI)) : 1430 PAGE_SIZE - offset_in_page(reg_read(ctxt, VCPU_REGS_RDI)); 1431 n = min3(in_page, (unsigned int)sizeof(rc->data) / size, count); 1432 if (n == 0) 1433 n = 1; 1434 rc->pos = rc->end = 0; 1435 if (!ctxt->ops->pio_in_emulated(ctxt, size, port, rc->data, n)) 1436 return 0; 1437 rc->end = n * size; 1438 } 1439 1440 if (ctxt->rep_prefix && (ctxt->d & String) && 1441 !(ctxt->eflags & X86_EFLAGS_DF)) { 1442 ctxt->dst.data = rc->data + rc->pos; 1443 ctxt->dst.type = OP_MEM_STR; 1444 ctxt->dst.count = (rc->end - rc->pos) / size; 1445 rc->pos = rc->end; 1446 } else { 1447 memcpy(dest, rc->data + rc->pos, size); 1448 rc->pos += size; 1449 } 1450 return 1; 1451 } 1452 1453 static int read_interrupt_descriptor(struct x86_emulate_ctxt *ctxt, 1454 u16 index, struct desc_struct *desc) 1455 { 1456 struct desc_ptr dt; 1457 ulong addr; 1458 1459 ctxt->ops->get_idt(ctxt, &dt); 1460 1461 if (dt.size < index * 8 + 7) 1462 return emulate_gp(ctxt, index << 3 | 0x2); 1463 1464 addr = dt.address + index * 8; 1465 return ctxt->ops->read_std(ctxt, addr, desc, sizeof *desc, 1466 &ctxt->exception); 1467 } 1468 1469 static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt, 1470 u16 selector, struct desc_ptr *dt) 1471 { 1472 const struct x86_emulate_ops *ops = ctxt->ops; 1473 u32 base3 = 0; 1474 1475 if (selector & 1 << 2) { 1476 struct desc_struct desc; 1477 u16 sel; 1478 1479 memset (dt, 0, sizeof *dt); 1480 if (!ops->get_segment(ctxt, &sel, &desc, &base3, 1481 VCPU_SREG_LDTR)) 1482 return; 1483 1484 dt->size = desc_limit_scaled(&desc); /* what if limit > 65535? */ 1485 dt->address = get_desc_base(&desc) | ((u64)base3 << 32); 1486 } else 1487 ops->get_gdt(ctxt, dt); 1488 } 1489 1490 static int get_descriptor_ptr(struct x86_emulate_ctxt *ctxt, 1491 u16 selector, ulong *desc_addr_p) 1492 { 1493 struct desc_ptr dt; 1494 u16 index = selector >> 3; 1495 ulong addr; 1496 1497 get_descriptor_table_ptr(ctxt, selector, &dt); 1498 1499 if (dt.size < index * 8 + 7) 1500 return emulate_gp(ctxt, selector & 0xfffc); 1501 1502 addr = dt.address + index * 8; 1503 1504 #ifdef CONFIG_X86_64 1505 if (addr >> 32 != 0) { 1506 u64 efer = 0; 1507 1508 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 1509 if (!(efer & EFER_LMA)) 1510 addr &= (u32)-1; 1511 } 1512 #endif 1513 1514 *desc_addr_p = addr; 1515 return X86EMUL_CONTINUE; 1516 } 1517 1518 /* allowed just for 8 bytes segments */ 1519 static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt, 1520 u16 selector, struct desc_struct *desc, 1521 ulong *desc_addr_p) 1522 { 1523 int rc; 1524 1525 rc = get_descriptor_ptr(ctxt, selector, desc_addr_p); 1526 if (rc != X86EMUL_CONTINUE) 1527 return rc; 1528 1529 return ctxt->ops->read_std(ctxt, *desc_addr_p, desc, sizeof(*desc), 1530 &ctxt->exception); 1531 } 1532 1533 /* allowed just for 8 bytes segments */ 1534 static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt, 1535 u16 selector, struct desc_struct *desc) 1536 { 1537 int rc; 1538 ulong addr; 1539 1540 rc = get_descriptor_ptr(ctxt, selector, &addr); 1541 if (rc != X86EMUL_CONTINUE) 1542 return rc; 1543 1544 return ctxt->ops->write_std(ctxt, addr, desc, sizeof *desc, 1545 &ctxt->exception); 1546 } 1547 1548 /* Does not support long mode */ 1549 static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt, 1550 u16 selector, int seg, u8 cpl, 1551 enum x86_transfer_type transfer, 1552 struct desc_struct *desc) 1553 { 1554 struct desc_struct seg_desc, old_desc; 1555 u8 dpl, rpl; 1556 unsigned err_vec = GP_VECTOR; 1557 u32 err_code = 0; 1558 bool null_selector = !(selector & ~0x3); /* 0000-0003 are null */ 1559 ulong desc_addr; 1560 int ret; 1561 u16 dummy; 1562 u32 base3 = 0; 1563 1564 memset(&seg_desc, 0, sizeof seg_desc); 1565 1566 if (ctxt->mode == X86EMUL_MODE_REAL) { 1567 /* set real mode segment descriptor (keep limit etc. for 1568 * unreal mode) */ 1569 ctxt->ops->get_segment(ctxt, &dummy, &seg_desc, NULL, seg); 1570 set_desc_base(&seg_desc, selector << 4); 1571 goto load; 1572 } else if (seg <= VCPU_SREG_GS && ctxt->mode == X86EMUL_MODE_VM86) { 1573 /* VM86 needs a clean new segment descriptor */ 1574 set_desc_base(&seg_desc, selector << 4); 1575 set_desc_limit(&seg_desc, 0xffff); 1576 seg_desc.type = 3; 1577 seg_desc.p = 1; 1578 seg_desc.s = 1; 1579 seg_desc.dpl = 3; 1580 goto load; 1581 } 1582 1583 rpl = selector & 3; 1584 1585 /* NULL selector is not valid for TR, CS and SS (except for long mode) */ 1586 if ((seg == VCPU_SREG_CS 1587 || (seg == VCPU_SREG_SS 1588 && (ctxt->mode != X86EMUL_MODE_PROT64 || rpl != cpl)) 1589 || seg == VCPU_SREG_TR) 1590 && null_selector) 1591 goto exception; 1592 1593 /* TR should be in GDT only */ 1594 if (seg == VCPU_SREG_TR && (selector & (1 << 2))) 1595 goto exception; 1596 1597 if (null_selector) /* for NULL selector skip all following checks */ 1598 goto load; 1599 1600 ret = read_segment_descriptor(ctxt, selector, &seg_desc, &desc_addr); 1601 if (ret != X86EMUL_CONTINUE) 1602 return ret; 1603 1604 err_code = selector & 0xfffc; 1605 err_vec = (transfer == X86_TRANSFER_TASK_SWITCH) ? TS_VECTOR : 1606 GP_VECTOR; 1607 1608 /* can't load system descriptor into segment selector */ 1609 if (seg <= VCPU_SREG_GS && !seg_desc.s) { 1610 if (transfer == X86_TRANSFER_CALL_JMP) 1611 return X86EMUL_UNHANDLEABLE; 1612 goto exception; 1613 } 1614 1615 if (!seg_desc.p) { 1616 err_vec = (seg == VCPU_SREG_SS) ? SS_VECTOR : NP_VECTOR; 1617 goto exception; 1618 } 1619 1620 dpl = seg_desc.dpl; 1621 1622 switch (seg) { 1623 case VCPU_SREG_SS: 1624 /* 1625 * segment is not a writable data segment or segment 1626 * selector's RPL != CPL or segment selector's RPL != CPL 1627 */ 1628 if (rpl != cpl || (seg_desc.type & 0xa) != 0x2 || dpl != cpl) 1629 goto exception; 1630 break; 1631 case VCPU_SREG_CS: 1632 if (!(seg_desc.type & 8)) 1633 goto exception; 1634 1635 if (seg_desc.type & 4) { 1636 /* conforming */ 1637 if (dpl > cpl) 1638 goto exception; 1639 } else { 1640 /* nonconforming */ 1641 if (rpl > cpl || dpl != cpl) 1642 goto exception; 1643 } 1644 /* in long-mode d/b must be clear if l is set */ 1645 if (seg_desc.d && seg_desc.l) { 1646 u64 efer = 0; 1647 1648 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 1649 if (efer & EFER_LMA) 1650 goto exception; 1651 } 1652 1653 /* CS(RPL) <- CPL */ 1654 selector = (selector & 0xfffc) | cpl; 1655 break; 1656 case VCPU_SREG_TR: 1657 if (seg_desc.s || (seg_desc.type != 1 && seg_desc.type != 9)) 1658 goto exception; 1659 old_desc = seg_desc; 1660 seg_desc.type |= 2; /* busy */ 1661 ret = ctxt->ops->cmpxchg_emulated(ctxt, desc_addr, &old_desc, &seg_desc, 1662 sizeof(seg_desc), &ctxt->exception); 1663 if (ret != X86EMUL_CONTINUE) 1664 return ret; 1665 break; 1666 case VCPU_SREG_LDTR: 1667 if (seg_desc.s || seg_desc.type != 2) 1668 goto exception; 1669 break; 1670 default: /* DS, ES, FS, or GS */ 1671 /* 1672 * segment is not a data or readable code segment or 1673 * ((segment is a data or nonconforming code segment) 1674 * and (both RPL and CPL > DPL)) 1675 */ 1676 if ((seg_desc.type & 0xa) == 0x8 || 1677 (((seg_desc.type & 0xc) != 0xc) && 1678 (rpl > dpl && cpl > dpl))) 1679 goto exception; 1680 break; 1681 } 1682 1683 if (seg_desc.s) { 1684 /* mark segment as accessed */ 1685 if (!(seg_desc.type & 1)) { 1686 seg_desc.type |= 1; 1687 ret = write_segment_descriptor(ctxt, selector, 1688 &seg_desc); 1689 if (ret != X86EMUL_CONTINUE) 1690 return ret; 1691 } 1692 } else if (ctxt->mode == X86EMUL_MODE_PROT64) { 1693 ret = ctxt->ops->read_std(ctxt, desc_addr+8, &base3, 1694 sizeof(base3), &ctxt->exception); 1695 if (ret != X86EMUL_CONTINUE) 1696 return ret; 1697 if (is_noncanonical_address(get_desc_base(&seg_desc) | 1698 ((u64)base3 << 32))) 1699 return emulate_gp(ctxt, 0); 1700 } 1701 load: 1702 ctxt->ops->set_segment(ctxt, selector, &seg_desc, base3, seg); 1703 if (desc) 1704 *desc = seg_desc; 1705 return X86EMUL_CONTINUE; 1706 exception: 1707 return emulate_exception(ctxt, err_vec, err_code, true); 1708 } 1709 1710 static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt, 1711 u16 selector, int seg) 1712 { 1713 u8 cpl = ctxt->ops->cpl(ctxt); 1714 return __load_segment_descriptor(ctxt, selector, seg, cpl, 1715 X86_TRANSFER_NONE, NULL); 1716 } 1717 1718 static void write_register_operand(struct operand *op) 1719 { 1720 return assign_register(op->addr.reg, op->val, op->bytes); 1721 } 1722 1723 static int writeback(struct x86_emulate_ctxt *ctxt, struct operand *op) 1724 { 1725 switch (op->type) { 1726 case OP_REG: 1727 write_register_operand(op); 1728 break; 1729 case OP_MEM: 1730 if (ctxt->lock_prefix) 1731 return segmented_cmpxchg(ctxt, 1732 op->addr.mem, 1733 &op->orig_val, 1734 &op->val, 1735 op->bytes); 1736 else 1737 return segmented_write(ctxt, 1738 op->addr.mem, 1739 &op->val, 1740 op->bytes); 1741 break; 1742 case OP_MEM_STR: 1743 return segmented_write(ctxt, 1744 op->addr.mem, 1745 op->data, 1746 op->bytes * op->count); 1747 break; 1748 case OP_XMM: 1749 write_sse_reg(ctxt, &op->vec_val, op->addr.xmm); 1750 break; 1751 case OP_MM: 1752 write_mmx_reg(ctxt, &op->mm_val, op->addr.mm); 1753 break; 1754 case OP_NONE: 1755 /* no writeback */ 1756 break; 1757 default: 1758 break; 1759 } 1760 return X86EMUL_CONTINUE; 1761 } 1762 1763 static int push(struct x86_emulate_ctxt *ctxt, void *data, int bytes) 1764 { 1765 struct segmented_address addr; 1766 1767 rsp_increment(ctxt, -bytes); 1768 addr.ea = reg_read(ctxt, VCPU_REGS_RSP) & stack_mask(ctxt); 1769 addr.seg = VCPU_SREG_SS; 1770 1771 return segmented_write(ctxt, addr, data, bytes); 1772 } 1773 1774 static int em_push(struct x86_emulate_ctxt *ctxt) 1775 { 1776 /* Disable writeback. */ 1777 ctxt->dst.type = OP_NONE; 1778 return push(ctxt, &ctxt->src.val, ctxt->op_bytes); 1779 } 1780 1781 static int emulate_pop(struct x86_emulate_ctxt *ctxt, 1782 void *dest, int len) 1783 { 1784 int rc; 1785 struct segmented_address addr; 1786 1787 addr.ea = reg_read(ctxt, VCPU_REGS_RSP) & stack_mask(ctxt); 1788 addr.seg = VCPU_SREG_SS; 1789 rc = segmented_read(ctxt, addr, dest, len); 1790 if (rc != X86EMUL_CONTINUE) 1791 return rc; 1792 1793 rsp_increment(ctxt, len); 1794 return rc; 1795 } 1796 1797 static int em_pop(struct x86_emulate_ctxt *ctxt) 1798 { 1799 return emulate_pop(ctxt, &ctxt->dst.val, ctxt->op_bytes); 1800 } 1801 1802 static int emulate_popf(struct x86_emulate_ctxt *ctxt, 1803 void *dest, int len) 1804 { 1805 int rc; 1806 unsigned long val, change_mask; 1807 int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> X86_EFLAGS_IOPL_BIT; 1808 int cpl = ctxt->ops->cpl(ctxt); 1809 1810 rc = emulate_pop(ctxt, &val, len); 1811 if (rc != X86EMUL_CONTINUE) 1812 return rc; 1813 1814 change_mask = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF | 1815 X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF | 1816 X86_EFLAGS_TF | X86_EFLAGS_DF | X86_EFLAGS_NT | 1817 X86_EFLAGS_AC | X86_EFLAGS_ID; 1818 1819 switch(ctxt->mode) { 1820 case X86EMUL_MODE_PROT64: 1821 case X86EMUL_MODE_PROT32: 1822 case X86EMUL_MODE_PROT16: 1823 if (cpl == 0) 1824 change_mask |= X86_EFLAGS_IOPL; 1825 if (cpl <= iopl) 1826 change_mask |= X86_EFLAGS_IF; 1827 break; 1828 case X86EMUL_MODE_VM86: 1829 if (iopl < 3) 1830 return emulate_gp(ctxt, 0); 1831 change_mask |= X86_EFLAGS_IF; 1832 break; 1833 default: /* real mode */ 1834 change_mask |= (X86_EFLAGS_IOPL | X86_EFLAGS_IF); 1835 break; 1836 } 1837 1838 *(unsigned long *)dest = 1839 (ctxt->eflags & ~change_mask) | (val & change_mask); 1840 1841 return rc; 1842 } 1843 1844 static int em_popf(struct x86_emulate_ctxt *ctxt) 1845 { 1846 ctxt->dst.type = OP_REG; 1847 ctxt->dst.addr.reg = &ctxt->eflags; 1848 ctxt->dst.bytes = ctxt->op_bytes; 1849 return emulate_popf(ctxt, &ctxt->dst.val, ctxt->op_bytes); 1850 } 1851 1852 static int em_enter(struct x86_emulate_ctxt *ctxt) 1853 { 1854 int rc; 1855 unsigned frame_size = ctxt->src.val; 1856 unsigned nesting_level = ctxt->src2.val & 31; 1857 ulong rbp; 1858 1859 if (nesting_level) 1860 return X86EMUL_UNHANDLEABLE; 1861 1862 rbp = reg_read(ctxt, VCPU_REGS_RBP); 1863 rc = push(ctxt, &rbp, stack_size(ctxt)); 1864 if (rc != X86EMUL_CONTINUE) 1865 return rc; 1866 assign_masked(reg_rmw(ctxt, VCPU_REGS_RBP), reg_read(ctxt, VCPU_REGS_RSP), 1867 stack_mask(ctxt)); 1868 assign_masked(reg_rmw(ctxt, VCPU_REGS_RSP), 1869 reg_read(ctxt, VCPU_REGS_RSP) - frame_size, 1870 stack_mask(ctxt)); 1871 return X86EMUL_CONTINUE; 1872 } 1873 1874 static int em_leave(struct x86_emulate_ctxt *ctxt) 1875 { 1876 assign_masked(reg_rmw(ctxt, VCPU_REGS_RSP), reg_read(ctxt, VCPU_REGS_RBP), 1877 stack_mask(ctxt)); 1878 return emulate_pop(ctxt, reg_rmw(ctxt, VCPU_REGS_RBP), ctxt->op_bytes); 1879 } 1880 1881 static int em_push_sreg(struct x86_emulate_ctxt *ctxt) 1882 { 1883 int seg = ctxt->src2.val; 1884 1885 ctxt->src.val = get_segment_selector(ctxt, seg); 1886 if (ctxt->op_bytes == 4) { 1887 rsp_increment(ctxt, -2); 1888 ctxt->op_bytes = 2; 1889 } 1890 1891 return em_push(ctxt); 1892 } 1893 1894 static int em_pop_sreg(struct x86_emulate_ctxt *ctxt) 1895 { 1896 int seg = ctxt->src2.val; 1897 unsigned long selector; 1898 int rc; 1899 1900 rc = emulate_pop(ctxt, &selector, 2); 1901 if (rc != X86EMUL_CONTINUE) 1902 return rc; 1903 1904 if (ctxt->modrm_reg == VCPU_SREG_SS) 1905 ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS; 1906 if (ctxt->op_bytes > 2) 1907 rsp_increment(ctxt, ctxt->op_bytes - 2); 1908 1909 rc = load_segment_descriptor(ctxt, (u16)selector, seg); 1910 return rc; 1911 } 1912 1913 static int em_pusha(struct x86_emulate_ctxt *ctxt) 1914 { 1915 unsigned long old_esp = reg_read(ctxt, VCPU_REGS_RSP); 1916 int rc = X86EMUL_CONTINUE; 1917 int reg = VCPU_REGS_RAX; 1918 1919 while (reg <= VCPU_REGS_RDI) { 1920 (reg == VCPU_REGS_RSP) ? 1921 (ctxt->src.val = old_esp) : (ctxt->src.val = reg_read(ctxt, reg)); 1922 1923 rc = em_push(ctxt); 1924 if (rc != X86EMUL_CONTINUE) 1925 return rc; 1926 1927 ++reg; 1928 } 1929 1930 return rc; 1931 } 1932 1933 static int em_pushf(struct x86_emulate_ctxt *ctxt) 1934 { 1935 ctxt->src.val = (unsigned long)ctxt->eflags & ~X86_EFLAGS_VM; 1936 return em_push(ctxt); 1937 } 1938 1939 static int em_popa(struct x86_emulate_ctxt *ctxt) 1940 { 1941 int rc = X86EMUL_CONTINUE; 1942 int reg = VCPU_REGS_RDI; 1943 u32 val; 1944 1945 while (reg >= VCPU_REGS_RAX) { 1946 if (reg == VCPU_REGS_RSP) { 1947 rsp_increment(ctxt, ctxt->op_bytes); 1948 --reg; 1949 } 1950 1951 rc = emulate_pop(ctxt, &val, ctxt->op_bytes); 1952 if (rc != X86EMUL_CONTINUE) 1953 break; 1954 assign_register(reg_rmw(ctxt, reg), val, ctxt->op_bytes); 1955 --reg; 1956 } 1957 return rc; 1958 } 1959 1960 static int __emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq) 1961 { 1962 const struct x86_emulate_ops *ops = ctxt->ops; 1963 int rc; 1964 struct desc_ptr dt; 1965 gva_t cs_addr; 1966 gva_t eip_addr; 1967 u16 cs, eip; 1968 1969 /* TODO: Add limit checks */ 1970 ctxt->src.val = ctxt->eflags; 1971 rc = em_push(ctxt); 1972 if (rc != X86EMUL_CONTINUE) 1973 return rc; 1974 1975 ctxt->eflags &= ~(X86_EFLAGS_IF | X86_EFLAGS_TF | X86_EFLAGS_AC); 1976 1977 ctxt->src.val = get_segment_selector(ctxt, VCPU_SREG_CS); 1978 rc = em_push(ctxt); 1979 if (rc != X86EMUL_CONTINUE) 1980 return rc; 1981 1982 ctxt->src.val = ctxt->_eip; 1983 rc = em_push(ctxt); 1984 if (rc != X86EMUL_CONTINUE) 1985 return rc; 1986 1987 ops->get_idt(ctxt, &dt); 1988 1989 eip_addr = dt.address + (irq << 2); 1990 cs_addr = dt.address + (irq << 2) + 2; 1991 1992 rc = ops->read_std(ctxt, cs_addr, &cs, 2, &ctxt->exception); 1993 if (rc != X86EMUL_CONTINUE) 1994 return rc; 1995 1996 rc = ops->read_std(ctxt, eip_addr, &eip, 2, &ctxt->exception); 1997 if (rc != X86EMUL_CONTINUE) 1998 return rc; 1999 2000 rc = load_segment_descriptor(ctxt, cs, VCPU_SREG_CS); 2001 if (rc != X86EMUL_CONTINUE) 2002 return rc; 2003 2004 ctxt->_eip = eip; 2005 2006 return rc; 2007 } 2008 2009 int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq) 2010 { 2011 int rc; 2012 2013 invalidate_registers(ctxt); 2014 rc = __emulate_int_real(ctxt, irq); 2015 if (rc == X86EMUL_CONTINUE) 2016 writeback_registers(ctxt); 2017 return rc; 2018 } 2019 2020 static int emulate_int(struct x86_emulate_ctxt *ctxt, int irq) 2021 { 2022 switch(ctxt->mode) { 2023 case X86EMUL_MODE_REAL: 2024 return __emulate_int_real(ctxt, irq); 2025 case X86EMUL_MODE_VM86: 2026 case X86EMUL_MODE_PROT16: 2027 case X86EMUL_MODE_PROT32: 2028 case X86EMUL_MODE_PROT64: 2029 default: 2030 /* Protected mode interrupts unimplemented yet */ 2031 return X86EMUL_UNHANDLEABLE; 2032 } 2033 } 2034 2035 static int emulate_iret_real(struct x86_emulate_ctxt *ctxt) 2036 { 2037 int rc = X86EMUL_CONTINUE; 2038 unsigned long temp_eip = 0; 2039 unsigned long temp_eflags = 0; 2040 unsigned long cs = 0; 2041 unsigned long mask = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF | 2042 X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_TF | 2043 X86_EFLAGS_IF | X86_EFLAGS_DF | X86_EFLAGS_OF | 2044 X86_EFLAGS_IOPL | X86_EFLAGS_NT | X86_EFLAGS_RF | 2045 X86_EFLAGS_AC | X86_EFLAGS_ID | 2046 X86_EFLAGS_FIXED; 2047 unsigned long vm86_mask = X86_EFLAGS_VM | X86_EFLAGS_VIF | 2048 X86_EFLAGS_VIP; 2049 2050 /* TODO: Add stack limit check */ 2051 2052 rc = emulate_pop(ctxt, &temp_eip, ctxt->op_bytes); 2053 2054 if (rc != X86EMUL_CONTINUE) 2055 return rc; 2056 2057 if (temp_eip & ~0xffff) 2058 return emulate_gp(ctxt, 0); 2059 2060 rc = emulate_pop(ctxt, &cs, ctxt->op_bytes); 2061 2062 if (rc != X86EMUL_CONTINUE) 2063 return rc; 2064 2065 rc = emulate_pop(ctxt, &temp_eflags, ctxt->op_bytes); 2066 2067 if (rc != X86EMUL_CONTINUE) 2068 return rc; 2069 2070 rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS); 2071 2072 if (rc != X86EMUL_CONTINUE) 2073 return rc; 2074 2075 ctxt->_eip = temp_eip; 2076 2077 if (ctxt->op_bytes == 4) 2078 ctxt->eflags = ((temp_eflags & mask) | (ctxt->eflags & vm86_mask)); 2079 else if (ctxt->op_bytes == 2) { 2080 ctxt->eflags &= ~0xffff; 2081 ctxt->eflags |= temp_eflags; 2082 } 2083 2084 ctxt->eflags &= ~EFLG_RESERVED_ZEROS_MASK; /* Clear reserved zeros */ 2085 ctxt->eflags |= X86_EFLAGS_FIXED; 2086 ctxt->ops->set_nmi_mask(ctxt, false); 2087 2088 return rc; 2089 } 2090 2091 static int em_iret(struct x86_emulate_ctxt *ctxt) 2092 { 2093 switch(ctxt->mode) { 2094 case X86EMUL_MODE_REAL: 2095 return emulate_iret_real(ctxt); 2096 case X86EMUL_MODE_VM86: 2097 case X86EMUL_MODE_PROT16: 2098 case X86EMUL_MODE_PROT32: 2099 case X86EMUL_MODE_PROT64: 2100 default: 2101 /* iret from protected mode unimplemented yet */ 2102 return X86EMUL_UNHANDLEABLE; 2103 } 2104 } 2105 2106 static int em_jmp_far(struct x86_emulate_ctxt *ctxt) 2107 { 2108 int rc; 2109 unsigned short sel, old_sel; 2110 struct desc_struct old_desc, new_desc; 2111 const struct x86_emulate_ops *ops = ctxt->ops; 2112 u8 cpl = ctxt->ops->cpl(ctxt); 2113 2114 /* Assignment of RIP may only fail in 64-bit mode */ 2115 if (ctxt->mode == X86EMUL_MODE_PROT64) 2116 ops->get_segment(ctxt, &old_sel, &old_desc, NULL, 2117 VCPU_SREG_CS); 2118 2119 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2); 2120 2121 rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl, 2122 X86_TRANSFER_CALL_JMP, 2123 &new_desc); 2124 if (rc != X86EMUL_CONTINUE) 2125 return rc; 2126 2127 rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc); 2128 if (rc != X86EMUL_CONTINUE) { 2129 WARN_ON(ctxt->mode != X86EMUL_MODE_PROT64); 2130 /* assigning eip failed; restore the old cs */ 2131 ops->set_segment(ctxt, old_sel, &old_desc, 0, VCPU_SREG_CS); 2132 return rc; 2133 } 2134 return rc; 2135 } 2136 2137 static int em_jmp_abs(struct x86_emulate_ctxt *ctxt) 2138 { 2139 return assign_eip_near(ctxt, ctxt->src.val); 2140 } 2141 2142 static int em_call_near_abs(struct x86_emulate_ctxt *ctxt) 2143 { 2144 int rc; 2145 long int old_eip; 2146 2147 old_eip = ctxt->_eip; 2148 rc = assign_eip_near(ctxt, ctxt->src.val); 2149 if (rc != X86EMUL_CONTINUE) 2150 return rc; 2151 ctxt->src.val = old_eip; 2152 rc = em_push(ctxt); 2153 return rc; 2154 } 2155 2156 static int em_cmpxchg8b(struct x86_emulate_ctxt *ctxt) 2157 { 2158 u64 old = ctxt->dst.orig_val64; 2159 2160 if (ctxt->dst.bytes == 16) 2161 return X86EMUL_UNHANDLEABLE; 2162 2163 if (((u32) (old >> 0) != (u32) reg_read(ctxt, VCPU_REGS_RAX)) || 2164 ((u32) (old >> 32) != (u32) reg_read(ctxt, VCPU_REGS_RDX))) { 2165 *reg_write(ctxt, VCPU_REGS_RAX) = (u32) (old >> 0); 2166 *reg_write(ctxt, VCPU_REGS_RDX) = (u32) (old >> 32); 2167 ctxt->eflags &= ~X86_EFLAGS_ZF; 2168 } else { 2169 ctxt->dst.val64 = ((u64)reg_read(ctxt, VCPU_REGS_RCX) << 32) | 2170 (u32) reg_read(ctxt, VCPU_REGS_RBX); 2171 2172 ctxt->eflags |= X86_EFLAGS_ZF; 2173 } 2174 return X86EMUL_CONTINUE; 2175 } 2176 2177 static int em_ret(struct x86_emulate_ctxt *ctxt) 2178 { 2179 int rc; 2180 unsigned long eip; 2181 2182 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes); 2183 if (rc != X86EMUL_CONTINUE) 2184 return rc; 2185 2186 return assign_eip_near(ctxt, eip); 2187 } 2188 2189 static int em_ret_far(struct x86_emulate_ctxt *ctxt) 2190 { 2191 int rc; 2192 unsigned long eip, cs; 2193 u16 old_cs; 2194 int cpl = ctxt->ops->cpl(ctxt); 2195 struct desc_struct old_desc, new_desc; 2196 const struct x86_emulate_ops *ops = ctxt->ops; 2197 2198 if (ctxt->mode == X86EMUL_MODE_PROT64) 2199 ops->get_segment(ctxt, &old_cs, &old_desc, NULL, 2200 VCPU_SREG_CS); 2201 2202 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes); 2203 if (rc != X86EMUL_CONTINUE) 2204 return rc; 2205 rc = emulate_pop(ctxt, &cs, ctxt->op_bytes); 2206 if (rc != X86EMUL_CONTINUE) 2207 return rc; 2208 /* Outer-privilege level return is not implemented */ 2209 if (ctxt->mode >= X86EMUL_MODE_PROT16 && (cs & 3) > cpl) 2210 return X86EMUL_UNHANDLEABLE; 2211 rc = __load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS, cpl, 2212 X86_TRANSFER_RET, 2213 &new_desc); 2214 if (rc != X86EMUL_CONTINUE) 2215 return rc; 2216 rc = assign_eip_far(ctxt, eip, &new_desc); 2217 if (rc != X86EMUL_CONTINUE) { 2218 WARN_ON(ctxt->mode != X86EMUL_MODE_PROT64); 2219 ops->set_segment(ctxt, old_cs, &old_desc, 0, VCPU_SREG_CS); 2220 } 2221 return rc; 2222 } 2223 2224 static int em_ret_far_imm(struct x86_emulate_ctxt *ctxt) 2225 { 2226 int rc; 2227 2228 rc = em_ret_far(ctxt); 2229 if (rc != X86EMUL_CONTINUE) 2230 return rc; 2231 rsp_increment(ctxt, ctxt->src.val); 2232 return X86EMUL_CONTINUE; 2233 } 2234 2235 static int em_cmpxchg(struct x86_emulate_ctxt *ctxt) 2236 { 2237 /* Save real source value, then compare EAX against destination. */ 2238 ctxt->dst.orig_val = ctxt->dst.val; 2239 ctxt->dst.val = reg_read(ctxt, VCPU_REGS_RAX); 2240 ctxt->src.orig_val = ctxt->src.val; 2241 ctxt->src.val = ctxt->dst.orig_val; 2242 fastop(ctxt, em_cmp); 2243 2244 if (ctxt->eflags & X86_EFLAGS_ZF) { 2245 /* Success: write back to memory; no update of EAX */ 2246 ctxt->src.type = OP_NONE; 2247 ctxt->dst.val = ctxt->src.orig_val; 2248 } else { 2249 /* Failure: write the value we saw to EAX. */ 2250 ctxt->src.type = OP_REG; 2251 ctxt->src.addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); 2252 ctxt->src.val = ctxt->dst.orig_val; 2253 /* Create write-cycle to dest by writing the same value */ 2254 ctxt->dst.val = ctxt->dst.orig_val; 2255 } 2256 return X86EMUL_CONTINUE; 2257 } 2258 2259 static int em_lseg(struct x86_emulate_ctxt *ctxt) 2260 { 2261 int seg = ctxt->src2.val; 2262 unsigned short sel; 2263 int rc; 2264 2265 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2); 2266 2267 rc = load_segment_descriptor(ctxt, sel, seg); 2268 if (rc != X86EMUL_CONTINUE) 2269 return rc; 2270 2271 ctxt->dst.val = ctxt->src.val; 2272 return rc; 2273 } 2274 2275 static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt) 2276 { 2277 u32 eax, ebx, ecx, edx; 2278 2279 eax = 0x80000001; 2280 ecx = 0; 2281 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); 2282 return edx & bit(X86_FEATURE_LM); 2283 } 2284 2285 #define GET_SMSTATE(type, smbase, offset) \ 2286 ({ \ 2287 type __val; \ 2288 int r = ctxt->ops->read_phys(ctxt, smbase + offset, &__val, \ 2289 sizeof(__val)); \ 2290 if (r != X86EMUL_CONTINUE) \ 2291 return X86EMUL_UNHANDLEABLE; \ 2292 __val; \ 2293 }) 2294 2295 static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags) 2296 { 2297 desc->g = (flags >> 23) & 1; 2298 desc->d = (flags >> 22) & 1; 2299 desc->l = (flags >> 21) & 1; 2300 desc->avl = (flags >> 20) & 1; 2301 desc->p = (flags >> 15) & 1; 2302 desc->dpl = (flags >> 13) & 3; 2303 desc->s = (flags >> 12) & 1; 2304 desc->type = (flags >> 8) & 15; 2305 } 2306 2307 static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, u64 smbase, int n) 2308 { 2309 struct desc_struct desc; 2310 int offset; 2311 u16 selector; 2312 2313 selector = GET_SMSTATE(u32, smbase, 0x7fa8 + n * 4); 2314 2315 if (n < 3) 2316 offset = 0x7f84 + n * 12; 2317 else 2318 offset = 0x7f2c + (n - 3) * 12; 2319 2320 set_desc_base(&desc, GET_SMSTATE(u32, smbase, offset + 8)); 2321 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, offset + 4)); 2322 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, offset)); 2323 ctxt->ops->set_segment(ctxt, selector, &desc, 0, n); 2324 return X86EMUL_CONTINUE; 2325 } 2326 2327 static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, u64 smbase, int n) 2328 { 2329 struct desc_struct desc; 2330 int offset; 2331 u16 selector; 2332 u32 base3; 2333 2334 offset = 0x7e00 + n * 16; 2335 2336 selector = GET_SMSTATE(u16, smbase, offset); 2337 rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smbase, offset + 2) << 8); 2338 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, offset + 4)); 2339 set_desc_base(&desc, GET_SMSTATE(u32, smbase, offset + 8)); 2340 base3 = GET_SMSTATE(u32, smbase, offset + 12); 2341 2342 ctxt->ops->set_segment(ctxt, selector, &desc, base3, n); 2343 return X86EMUL_CONTINUE; 2344 } 2345 2346 static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt, 2347 u64 cr0, u64 cr4) 2348 { 2349 int bad; 2350 2351 /* 2352 * First enable PAE, long mode needs it before CR0.PG = 1 is set. 2353 * Then enable protected mode. However, PCID cannot be enabled 2354 * if EFER.LMA=0, so set it separately. 2355 */ 2356 bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE); 2357 if (bad) 2358 return X86EMUL_UNHANDLEABLE; 2359 2360 bad = ctxt->ops->set_cr(ctxt, 0, cr0); 2361 if (bad) 2362 return X86EMUL_UNHANDLEABLE; 2363 2364 if (cr4 & X86_CR4_PCIDE) { 2365 bad = ctxt->ops->set_cr(ctxt, 4, cr4); 2366 if (bad) 2367 return X86EMUL_UNHANDLEABLE; 2368 } 2369 2370 return X86EMUL_CONTINUE; 2371 } 2372 2373 static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt, u64 smbase) 2374 { 2375 struct desc_struct desc; 2376 struct desc_ptr dt; 2377 u16 selector; 2378 u32 val, cr0, cr4; 2379 int i; 2380 2381 cr0 = GET_SMSTATE(u32, smbase, 0x7ffc); 2382 ctxt->ops->set_cr(ctxt, 3, GET_SMSTATE(u32, smbase, 0x7ff8)); 2383 ctxt->eflags = GET_SMSTATE(u32, smbase, 0x7ff4) | X86_EFLAGS_FIXED; 2384 ctxt->_eip = GET_SMSTATE(u32, smbase, 0x7ff0); 2385 2386 for (i = 0; i < 8; i++) 2387 *reg_write(ctxt, i) = GET_SMSTATE(u32, smbase, 0x7fd0 + i * 4); 2388 2389 val = GET_SMSTATE(u32, smbase, 0x7fcc); 2390 ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1); 2391 val = GET_SMSTATE(u32, smbase, 0x7fc8); 2392 ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1); 2393 2394 selector = GET_SMSTATE(u32, smbase, 0x7fc4); 2395 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7f64)); 2396 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7f60)); 2397 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7f5c)); 2398 ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR); 2399 2400 selector = GET_SMSTATE(u32, smbase, 0x7fc0); 2401 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7f80)); 2402 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7f7c)); 2403 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7f78)); 2404 ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR); 2405 2406 dt.address = GET_SMSTATE(u32, smbase, 0x7f74); 2407 dt.size = GET_SMSTATE(u32, smbase, 0x7f70); 2408 ctxt->ops->set_gdt(ctxt, &dt); 2409 2410 dt.address = GET_SMSTATE(u32, smbase, 0x7f58); 2411 dt.size = GET_SMSTATE(u32, smbase, 0x7f54); 2412 ctxt->ops->set_idt(ctxt, &dt); 2413 2414 for (i = 0; i < 6; i++) { 2415 int r = rsm_load_seg_32(ctxt, smbase, i); 2416 if (r != X86EMUL_CONTINUE) 2417 return r; 2418 } 2419 2420 cr4 = GET_SMSTATE(u32, smbase, 0x7f14); 2421 2422 ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smbase, 0x7ef8)); 2423 2424 return rsm_enter_protected_mode(ctxt, cr0, cr4); 2425 } 2426 2427 static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt, u64 smbase) 2428 { 2429 struct desc_struct desc; 2430 struct desc_ptr dt; 2431 u64 val, cr0, cr4; 2432 u32 base3; 2433 u16 selector; 2434 int i, r; 2435 2436 for (i = 0; i < 16; i++) 2437 *reg_write(ctxt, i) = GET_SMSTATE(u64, smbase, 0x7ff8 - i * 8); 2438 2439 ctxt->_eip = GET_SMSTATE(u64, smbase, 0x7f78); 2440 ctxt->eflags = GET_SMSTATE(u32, smbase, 0x7f70) | X86_EFLAGS_FIXED; 2441 2442 val = GET_SMSTATE(u32, smbase, 0x7f68); 2443 ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1); 2444 val = GET_SMSTATE(u32, smbase, 0x7f60); 2445 ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1); 2446 2447 cr0 = GET_SMSTATE(u64, smbase, 0x7f58); 2448 ctxt->ops->set_cr(ctxt, 3, GET_SMSTATE(u64, smbase, 0x7f50)); 2449 cr4 = GET_SMSTATE(u64, smbase, 0x7f48); 2450 ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smbase, 0x7f00)); 2451 val = GET_SMSTATE(u64, smbase, 0x7ed0); 2452 ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA); 2453 2454 selector = GET_SMSTATE(u32, smbase, 0x7e90); 2455 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7e92) << 8); 2456 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7e94)); 2457 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7e98)); 2458 base3 = GET_SMSTATE(u32, smbase, 0x7e9c); 2459 ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR); 2460 2461 dt.size = GET_SMSTATE(u32, smbase, 0x7e84); 2462 dt.address = GET_SMSTATE(u64, smbase, 0x7e88); 2463 ctxt->ops->set_idt(ctxt, &dt); 2464 2465 selector = GET_SMSTATE(u32, smbase, 0x7e70); 2466 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7e72) << 8); 2467 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7e74)); 2468 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7e78)); 2469 base3 = GET_SMSTATE(u32, smbase, 0x7e7c); 2470 ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR); 2471 2472 dt.size = GET_SMSTATE(u32, smbase, 0x7e64); 2473 dt.address = GET_SMSTATE(u64, smbase, 0x7e68); 2474 ctxt->ops->set_gdt(ctxt, &dt); 2475 2476 r = rsm_enter_protected_mode(ctxt, cr0, cr4); 2477 if (r != X86EMUL_CONTINUE) 2478 return r; 2479 2480 for (i = 0; i < 6; i++) { 2481 r = rsm_load_seg_64(ctxt, smbase, i); 2482 if (r != X86EMUL_CONTINUE) 2483 return r; 2484 } 2485 2486 return X86EMUL_CONTINUE; 2487 } 2488 2489 static int em_rsm(struct x86_emulate_ctxt *ctxt) 2490 { 2491 unsigned long cr0, cr4, efer; 2492 u64 smbase; 2493 int ret; 2494 2495 if ((ctxt->emul_flags & X86EMUL_SMM_MASK) == 0) 2496 return emulate_ud(ctxt); 2497 2498 /* 2499 * Get back to real mode, to prepare a safe state in which to load 2500 * CR0/CR3/CR4/EFER. It's all a bit more complicated if the vCPU 2501 * supports long mode. 2502 */ 2503 cr4 = ctxt->ops->get_cr(ctxt, 4); 2504 if (emulator_has_longmode(ctxt)) { 2505 struct desc_struct cs_desc; 2506 2507 /* Zero CR4.PCIDE before CR0.PG. */ 2508 if (cr4 & X86_CR4_PCIDE) { 2509 ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE); 2510 cr4 &= ~X86_CR4_PCIDE; 2511 } 2512 2513 /* A 32-bit code segment is required to clear EFER.LMA. */ 2514 memset(&cs_desc, 0, sizeof(cs_desc)); 2515 cs_desc.type = 0xb; 2516 cs_desc.s = cs_desc.g = cs_desc.p = 1; 2517 ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS); 2518 } 2519 2520 /* For the 64-bit case, this will clear EFER.LMA. */ 2521 cr0 = ctxt->ops->get_cr(ctxt, 0); 2522 if (cr0 & X86_CR0_PE) 2523 ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE)); 2524 2525 /* Now clear CR4.PAE (which must be done before clearing EFER.LME). */ 2526 if (cr4 & X86_CR4_PAE) 2527 ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE); 2528 2529 /* And finally go back to 32-bit mode. */ 2530 efer = 0; 2531 ctxt->ops->set_msr(ctxt, MSR_EFER, efer); 2532 2533 smbase = ctxt->ops->get_smbase(ctxt); 2534 if (emulator_has_longmode(ctxt)) 2535 ret = rsm_load_state_64(ctxt, smbase + 0x8000); 2536 else 2537 ret = rsm_load_state_32(ctxt, smbase + 0x8000); 2538 2539 if (ret != X86EMUL_CONTINUE) { 2540 /* FIXME: should triple fault */ 2541 return X86EMUL_UNHANDLEABLE; 2542 } 2543 2544 if ((ctxt->emul_flags & X86EMUL_SMM_INSIDE_NMI_MASK) == 0) 2545 ctxt->ops->set_nmi_mask(ctxt, false); 2546 2547 ctxt->emul_flags &= ~X86EMUL_SMM_INSIDE_NMI_MASK; 2548 ctxt->emul_flags &= ~X86EMUL_SMM_MASK; 2549 return X86EMUL_CONTINUE; 2550 } 2551 2552 static void 2553 setup_syscalls_segments(struct x86_emulate_ctxt *ctxt, 2554 struct desc_struct *cs, struct desc_struct *ss) 2555 { 2556 cs->l = 0; /* will be adjusted later */ 2557 set_desc_base(cs, 0); /* flat segment */ 2558 cs->g = 1; /* 4kb granularity */ 2559 set_desc_limit(cs, 0xfffff); /* 4GB limit */ 2560 cs->type = 0x0b; /* Read, Execute, Accessed */ 2561 cs->s = 1; 2562 cs->dpl = 0; /* will be adjusted later */ 2563 cs->p = 1; 2564 cs->d = 1; 2565 cs->avl = 0; 2566 2567 set_desc_base(ss, 0); /* flat segment */ 2568 set_desc_limit(ss, 0xfffff); /* 4GB limit */ 2569 ss->g = 1; /* 4kb granularity */ 2570 ss->s = 1; 2571 ss->type = 0x03; /* Read/Write, Accessed */ 2572 ss->d = 1; /* 32bit stack segment */ 2573 ss->dpl = 0; 2574 ss->p = 1; 2575 ss->l = 0; 2576 ss->avl = 0; 2577 } 2578 2579 static bool vendor_intel(struct x86_emulate_ctxt *ctxt) 2580 { 2581 u32 eax, ebx, ecx, edx; 2582 2583 eax = ecx = 0; 2584 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); 2585 return ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx 2586 && ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx 2587 && edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx; 2588 } 2589 2590 static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt) 2591 { 2592 const struct x86_emulate_ops *ops = ctxt->ops; 2593 u32 eax, ebx, ecx, edx; 2594 2595 /* 2596 * syscall should always be enabled in longmode - so only become 2597 * vendor specific (cpuid) if other modes are active... 2598 */ 2599 if (ctxt->mode == X86EMUL_MODE_PROT64) 2600 return true; 2601 2602 eax = 0x00000000; 2603 ecx = 0x00000000; 2604 ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); 2605 /* 2606 * Intel ("GenuineIntel") 2607 * remark: Intel CPUs only support "syscall" in 64bit 2608 * longmode. Also an 64bit guest with a 2609 * 32bit compat-app running will #UD !! While this 2610 * behaviour can be fixed (by emulating) into AMD 2611 * response - CPUs of AMD can't behave like Intel. 2612 */ 2613 if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx && 2614 ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx && 2615 edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx) 2616 return false; 2617 2618 /* AMD ("AuthenticAMD") */ 2619 if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx && 2620 ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx && 2621 edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx) 2622 return true; 2623 2624 /* AMD ("AMDisbetter!") */ 2625 if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx && 2626 ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx && 2627 edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx) 2628 return true; 2629 2630 /* default: (not Intel, not AMD), apply Intel's stricter rules... */ 2631 return false; 2632 } 2633 2634 static int em_syscall(struct x86_emulate_ctxt *ctxt) 2635 { 2636 const struct x86_emulate_ops *ops = ctxt->ops; 2637 struct desc_struct cs, ss; 2638 u64 msr_data; 2639 u16 cs_sel, ss_sel; 2640 u64 efer = 0; 2641 2642 /* syscall is not available in real mode */ 2643 if (ctxt->mode == X86EMUL_MODE_REAL || 2644 ctxt->mode == X86EMUL_MODE_VM86) 2645 return emulate_ud(ctxt); 2646 2647 if (!(em_syscall_is_enabled(ctxt))) 2648 return emulate_ud(ctxt); 2649 2650 ops->get_msr(ctxt, MSR_EFER, &efer); 2651 setup_syscalls_segments(ctxt, &cs, &ss); 2652 2653 if (!(efer & EFER_SCE)) 2654 return emulate_ud(ctxt); 2655 2656 ops->get_msr(ctxt, MSR_STAR, &msr_data); 2657 msr_data >>= 32; 2658 cs_sel = (u16)(msr_data & 0xfffc); 2659 ss_sel = (u16)(msr_data + 8); 2660 2661 if (efer & EFER_LMA) { 2662 cs.d = 0; 2663 cs.l = 1; 2664 } 2665 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS); 2666 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS); 2667 2668 *reg_write(ctxt, VCPU_REGS_RCX) = ctxt->_eip; 2669 if (efer & EFER_LMA) { 2670 #ifdef CONFIG_X86_64 2671 *reg_write(ctxt, VCPU_REGS_R11) = ctxt->eflags; 2672 2673 ops->get_msr(ctxt, 2674 ctxt->mode == X86EMUL_MODE_PROT64 ? 2675 MSR_LSTAR : MSR_CSTAR, &msr_data); 2676 ctxt->_eip = msr_data; 2677 2678 ops->get_msr(ctxt, MSR_SYSCALL_MASK, &msr_data); 2679 ctxt->eflags &= ~msr_data; 2680 ctxt->eflags |= X86_EFLAGS_FIXED; 2681 #endif 2682 } else { 2683 /* legacy mode */ 2684 ops->get_msr(ctxt, MSR_STAR, &msr_data); 2685 ctxt->_eip = (u32)msr_data; 2686 2687 ctxt->eflags &= ~(X86_EFLAGS_VM | X86_EFLAGS_IF); 2688 } 2689 2690 return X86EMUL_CONTINUE; 2691 } 2692 2693 static int em_sysenter(struct x86_emulate_ctxt *ctxt) 2694 { 2695 const struct x86_emulate_ops *ops = ctxt->ops; 2696 struct desc_struct cs, ss; 2697 u64 msr_data; 2698 u16 cs_sel, ss_sel; 2699 u64 efer = 0; 2700 2701 ops->get_msr(ctxt, MSR_EFER, &efer); 2702 /* inject #GP if in real mode */ 2703 if (ctxt->mode == X86EMUL_MODE_REAL) 2704 return emulate_gp(ctxt, 0); 2705 2706 /* 2707 * Not recognized on AMD in compat mode (but is recognized in legacy 2708 * mode). 2709 */ 2710 if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA) 2711 && !vendor_intel(ctxt)) 2712 return emulate_ud(ctxt); 2713 2714 /* sysenter/sysexit have not been tested in 64bit mode. */ 2715 if (ctxt->mode == X86EMUL_MODE_PROT64) 2716 return X86EMUL_UNHANDLEABLE; 2717 2718 setup_syscalls_segments(ctxt, &cs, &ss); 2719 2720 ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data); 2721 if ((msr_data & 0xfffc) == 0x0) 2722 return emulate_gp(ctxt, 0); 2723 2724 ctxt->eflags &= ~(X86_EFLAGS_VM | X86_EFLAGS_IF); 2725 cs_sel = (u16)msr_data & ~SEGMENT_RPL_MASK; 2726 ss_sel = cs_sel + 8; 2727 if (efer & EFER_LMA) { 2728 cs.d = 0; 2729 cs.l = 1; 2730 } 2731 2732 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS); 2733 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS); 2734 2735 ops->get_msr(ctxt, MSR_IA32_SYSENTER_EIP, &msr_data); 2736 ctxt->_eip = (efer & EFER_LMA) ? msr_data : (u32)msr_data; 2737 2738 ops->get_msr(ctxt, MSR_IA32_SYSENTER_ESP, &msr_data); 2739 *reg_write(ctxt, VCPU_REGS_RSP) = (efer & EFER_LMA) ? msr_data : 2740 (u32)msr_data; 2741 2742 return X86EMUL_CONTINUE; 2743 } 2744 2745 static int em_sysexit(struct x86_emulate_ctxt *ctxt) 2746 { 2747 const struct x86_emulate_ops *ops = ctxt->ops; 2748 struct desc_struct cs, ss; 2749 u64 msr_data, rcx, rdx; 2750 int usermode; 2751 u16 cs_sel = 0, ss_sel = 0; 2752 2753 /* inject #GP if in real mode or Virtual 8086 mode */ 2754 if (ctxt->mode == X86EMUL_MODE_REAL || 2755 ctxt->mode == X86EMUL_MODE_VM86) 2756 return emulate_gp(ctxt, 0); 2757 2758 setup_syscalls_segments(ctxt, &cs, &ss); 2759 2760 if ((ctxt->rex_prefix & 0x8) != 0x0) 2761 usermode = X86EMUL_MODE_PROT64; 2762 else 2763 usermode = X86EMUL_MODE_PROT32; 2764 2765 rcx = reg_read(ctxt, VCPU_REGS_RCX); 2766 rdx = reg_read(ctxt, VCPU_REGS_RDX); 2767 2768 cs.dpl = 3; 2769 ss.dpl = 3; 2770 ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data); 2771 switch (usermode) { 2772 case X86EMUL_MODE_PROT32: 2773 cs_sel = (u16)(msr_data + 16); 2774 if ((msr_data & 0xfffc) == 0x0) 2775 return emulate_gp(ctxt, 0); 2776 ss_sel = (u16)(msr_data + 24); 2777 rcx = (u32)rcx; 2778 rdx = (u32)rdx; 2779 break; 2780 case X86EMUL_MODE_PROT64: 2781 cs_sel = (u16)(msr_data + 32); 2782 if (msr_data == 0x0) 2783 return emulate_gp(ctxt, 0); 2784 ss_sel = cs_sel + 8; 2785 cs.d = 0; 2786 cs.l = 1; 2787 if (is_noncanonical_address(rcx) || 2788 is_noncanonical_address(rdx)) 2789 return emulate_gp(ctxt, 0); 2790 break; 2791 } 2792 cs_sel |= SEGMENT_RPL_MASK; 2793 ss_sel |= SEGMENT_RPL_MASK; 2794 2795 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS); 2796 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS); 2797 2798 ctxt->_eip = rdx; 2799 *reg_write(ctxt, VCPU_REGS_RSP) = rcx; 2800 2801 return X86EMUL_CONTINUE; 2802 } 2803 2804 static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt) 2805 { 2806 int iopl; 2807 if (ctxt->mode == X86EMUL_MODE_REAL) 2808 return false; 2809 if (ctxt->mode == X86EMUL_MODE_VM86) 2810 return true; 2811 iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> X86_EFLAGS_IOPL_BIT; 2812 return ctxt->ops->cpl(ctxt) > iopl; 2813 } 2814 2815 static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt, 2816 u16 port, u16 len) 2817 { 2818 const struct x86_emulate_ops *ops = ctxt->ops; 2819 struct desc_struct tr_seg; 2820 u32 base3; 2821 int r; 2822 u16 tr, io_bitmap_ptr, perm, bit_idx = port & 0x7; 2823 unsigned mask = (1 << len) - 1; 2824 unsigned long base; 2825 2826 ops->get_segment(ctxt, &tr, &tr_seg, &base3, VCPU_SREG_TR); 2827 if (!tr_seg.p) 2828 return false; 2829 if (desc_limit_scaled(&tr_seg) < 103) 2830 return false; 2831 base = get_desc_base(&tr_seg); 2832 #ifdef CONFIG_X86_64 2833 base |= ((u64)base3) << 32; 2834 #endif 2835 r = ops->read_std(ctxt, base + 102, &io_bitmap_ptr, 2, NULL); 2836 if (r != X86EMUL_CONTINUE) 2837 return false; 2838 if (io_bitmap_ptr + port/8 > desc_limit_scaled(&tr_seg)) 2839 return false; 2840 r = ops->read_std(ctxt, base + io_bitmap_ptr + port/8, &perm, 2, NULL); 2841 if (r != X86EMUL_CONTINUE) 2842 return false; 2843 if ((perm >> bit_idx) & mask) 2844 return false; 2845 return true; 2846 } 2847 2848 static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt, 2849 u16 port, u16 len) 2850 { 2851 if (ctxt->perm_ok) 2852 return true; 2853 2854 if (emulator_bad_iopl(ctxt)) 2855 if (!emulator_io_port_access_allowed(ctxt, port, len)) 2856 return false; 2857 2858 ctxt->perm_ok = true; 2859 2860 return true; 2861 } 2862 2863 static void string_registers_quirk(struct x86_emulate_ctxt *ctxt) 2864 { 2865 /* 2866 * Intel CPUs mask the counter and pointers in quite strange 2867 * manner when ECX is zero due to REP-string optimizations. 2868 */ 2869 #ifdef CONFIG_X86_64 2870 if (ctxt->ad_bytes != 4 || !vendor_intel(ctxt)) 2871 return; 2872 2873 *reg_write(ctxt, VCPU_REGS_RCX) = 0; 2874 2875 switch (ctxt->b) { 2876 case 0xa4: /* movsb */ 2877 case 0xa5: /* movsd/w */ 2878 *reg_rmw(ctxt, VCPU_REGS_RSI) &= (u32)-1; 2879 /* fall through */ 2880 case 0xaa: /* stosb */ 2881 case 0xab: /* stosd/w */ 2882 *reg_rmw(ctxt, VCPU_REGS_RDI) &= (u32)-1; 2883 } 2884 #endif 2885 } 2886 2887 static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt, 2888 struct tss_segment_16 *tss) 2889 { 2890 tss->ip = ctxt->_eip; 2891 tss->flag = ctxt->eflags; 2892 tss->ax = reg_read(ctxt, VCPU_REGS_RAX); 2893 tss->cx = reg_read(ctxt, VCPU_REGS_RCX); 2894 tss->dx = reg_read(ctxt, VCPU_REGS_RDX); 2895 tss->bx = reg_read(ctxt, VCPU_REGS_RBX); 2896 tss->sp = reg_read(ctxt, VCPU_REGS_RSP); 2897 tss->bp = reg_read(ctxt, VCPU_REGS_RBP); 2898 tss->si = reg_read(ctxt, VCPU_REGS_RSI); 2899 tss->di = reg_read(ctxt, VCPU_REGS_RDI); 2900 2901 tss->es = get_segment_selector(ctxt, VCPU_SREG_ES); 2902 tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS); 2903 tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS); 2904 tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS); 2905 tss->ldt = get_segment_selector(ctxt, VCPU_SREG_LDTR); 2906 } 2907 2908 static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt, 2909 struct tss_segment_16 *tss) 2910 { 2911 int ret; 2912 u8 cpl; 2913 2914 ctxt->_eip = tss->ip; 2915 ctxt->eflags = tss->flag | 2; 2916 *reg_write(ctxt, VCPU_REGS_RAX) = tss->ax; 2917 *reg_write(ctxt, VCPU_REGS_RCX) = tss->cx; 2918 *reg_write(ctxt, VCPU_REGS_RDX) = tss->dx; 2919 *reg_write(ctxt, VCPU_REGS_RBX) = tss->bx; 2920 *reg_write(ctxt, VCPU_REGS_RSP) = tss->sp; 2921 *reg_write(ctxt, VCPU_REGS_RBP) = tss->bp; 2922 *reg_write(ctxt, VCPU_REGS_RSI) = tss->si; 2923 *reg_write(ctxt, VCPU_REGS_RDI) = tss->di; 2924 2925 /* 2926 * SDM says that segment selectors are loaded before segment 2927 * descriptors 2928 */ 2929 set_segment_selector(ctxt, tss->ldt, VCPU_SREG_LDTR); 2930 set_segment_selector(ctxt, tss->es, VCPU_SREG_ES); 2931 set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS); 2932 set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS); 2933 set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS); 2934 2935 cpl = tss->cs & 3; 2936 2937 /* 2938 * Now load segment descriptors. If fault happens at this stage 2939 * it is handled in a context of new task 2940 */ 2941 ret = __load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR, cpl, 2942 X86_TRANSFER_TASK_SWITCH, NULL); 2943 if (ret != X86EMUL_CONTINUE) 2944 return ret; 2945 ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl, 2946 X86_TRANSFER_TASK_SWITCH, NULL); 2947 if (ret != X86EMUL_CONTINUE) 2948 return ret; 2949 ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl, 2950 X86_TRANSFER_TASK_SWITCH, NULL); 2951 if (ret != X86EMUL_CONTINUE) 2952 return ret; 2953 ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl, 2954 X86_TRANSFER_TASK_SWITCH, NULL); 2955 if (ret != X86EMUL_CONTINUE) 2956 return ret; 2957 ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl, 2958 X86_TRANSFER_TASK_SWITCH, NULL); 2959 if (ret != X86EMUL_CONTINUE) 2960 return ret; 2961 2962 return X86EMUL_CONTINUE; 2963 } 2964 2965 static int task_switch_16(struct x86_emulate_ctxt *ctxt, 2966 u16 tss_selector, u16 old_tss_sel, 2967 ulong old_tss_base, struct desc_struct *new_desc) 2968 { 2969 const struct x86_emulate_ops *ops = ctxt->ops; 2970 struct tss_segment_16 tss_seg; 2971 int ret; 2972 u32 new_tss_base = get_desc_base(new_desc); 2973 2974 ret = ops->read_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg, 2975 &ctxt->exception); 2976 if (ret != X86EMUL_CONTINUE) 2977 return ret; 2978 2979 save_state_to_tss16(ctxt, &tss_seg); 2980 2981 ret = ops->write_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg, 2982 &ctxt->exception); 2983 if (ret != X86EMUL_CONTINUE) 2984 return ret; 2985 2986 ret = ops->read_std(ctxt, new_tss_base, &tss_seg, sizeof tss_seg, 2987 &ctxt->exception); 2988 if (ret != X86EMUL_CONTINUE) 2989 return ret; 2990 2991 if (old_tss_sel != 0xffff) { 2992 tss_seg.prev_task_link = old_tss_sel; 2993 2994 ret = ops->write_std(ctxt, new_tss_base, 2995 &tss_seg.prev_task_link, 2996 sizeof tss_seg.prev_task_link, 2997 &ctxt->exception); 2998 if (ret != X86EMUL_CONTINUE) 2999 return ret; 3000 } 3001 3002 return load_state_from_tss16(ctxt, &tss_seg); 3003 } 3004 3005 static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt, 3006 struct tss_segment_32 *tss) 3007 { 3008 /* CR3 and ldt selector are not saved intentionally */ 3009 tss->eip = ctxt->_eip; 3010 tss->eflags = ctxt->eflags; 3011 tss->eax = reg_read(ctxt, VCPU_REGS_RAX); 3012 tss->ecx = reg_read(ctxt, VCPU_REGS_RCX); 3013 tss->edx = reg_read(ctxt, VCPU_REGS_RDX); 3014 tss->ebx = reg_read(ctxt, VCPU_REGS_RBX); 3015 tss->esp = reg_read(ctxt, VCPU_REGS_RSP); 3016 tss->ebp = reg_read(ctxt, VCPU_REGS_RBP); 3017 tss->esi = reg_read(ctxt, VCPU_REGS_RSI); 3018 tss->edi = reg_read(ctxt, VCPU_REGS_RDI); 3019 3020 tss->es = get_segment_selector(ctxt, VCPU_SREG_ES); 3021 tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS); 3022 tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS); 3023 tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS); 3024 tss->fs = get_segment_selector(ctxt, VCPU_SREG_FS); 3025 tss->gs = get_segment_selector(ctxt, VCPU_SREG_GS); 3026 } 3027 3028 static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt, 3029 struct tss_segment_32 *tss) 3030 { 3031 int ret; 3032 u8 cpl; 3033 3034 if (ctxt->ops->set_cr(ctxt, 3, tss->cr3)) 3035 return emulate_gp(ctxt, 0); 3036 ctxt->_eip = tss->eip; 3037 ctxt->eflags = tss->eflags | 2; 3038 3039 /* General purpose registers */ 3040 *reg_write(ctxt, VCPU_REGS_RAX) = tss->eax; 3041 *reg_write(ctxt, VCPU_REGS_RCX) = tss->ecx; 3042 *reg_write(ctxt, VCPU_REGS_RDX) = tss->edx; 3043 *reg_write(ctxt, VCPU_REGS_RBX) = tss->ebx; 3044 *reg_write(ctxt, VCPU_REGS_RSP) = tss->esp; 3045 *reg_write(ctxt, VCPU_REGS_RBP) = tss->ebp; 3046 *reg_write(ctxt, VCPU_REGS_RSI) = tss->esi; 3047 *reg_write(ctxt, VCPU_REGS_RDI) = tss->edi; 3048 3049 /* 3050 * SDM says that segment selectors are loaded before segment 3051 * descriptors. This is important because CPL checks will 3052 * use CS.RPL. 3053 */ 3054 set_segment_selector(ctxt, tss->ldt_selector, VCPU_SREG_LDTR); 3055 set_segment_selector(ctxt, tss->es, VCPU_SREG_ES); 3056 set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS); 3057 set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS); 3058 set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS); 3059 set_segment_selector(ctxt, tss->fs, VCPU_SREG_FS); 3060 set_segment_selector(ctxt, tss->gs, VCPU_SREG_GS); 3061 3062 /* 3063 * If we're switching between Protected Mode and VM86, we need to make 3064 * sure to update the mode before loading the segment descriptors so 3065 * that the selectors are interpreted correctly. 3066 */ 3067 if (ctxt->eflags & X86_EFLAGS_VM) { 3068 ctxt->mode = X86EMUL_MODE_VM86; 3069 cpl = 3; 3070 } else { 3071 ctxt->mode = X86EMUL_MODE_PROT32; 3072 cpl = tss->cs & 3; 3073 } 3074 3075 /* 3076 * Now load segment descriptors. If fault happenes at this stage 3077 * it is handled in a context of new task 3078 */ 3079 ret = __load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR, 3080 cpl, X86_TRANSFER_TASK_SWITCH, NULL); 3081 if (ret != X86EMUL_CONTINUE) 3082 return ret; 3083 ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl, 3084 X86_TRANSFER_TASK_SWITCH, NULL); 3085 if (ret != X86EMUL_CONTINUE) 3086 return ret; 3087 ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl, 3088 X86_TRANSFER_TASK_SWITCH, NULL); 3089 if (ret != X86EMUL_CONTINUE) 3090 return ret; 3091 ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl, 3092 X86_TRANSFER_TASK_SWITCH, NULL); 3093 if (ret != X86EMUL_CONTINUE) 3094 return ret; 3095 ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl, 3096 X86_TRANSFER_TASK_SWITCH, NULL); 3097 if (ret != X86EMUL_CONTINUE) 3098 return ret; 3099 ret = __load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS, cpl, 3100 X86_TRANSFER_TASK_SWITCH, NULL); 3101 if (ret != X86EMUL_CONTINUE) 3102 return ret; 3103 ret = __load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS, cpl, 3104 X86_TRANSFER_TASK_SWITCH, NULL); 3105 3106 return ret; 3107 } 3108 3109 static int task_switch_32(struct x86_emulate_ctxt *ctxt, 3110 u16 tss_selector, u16 old_tss_sel, 3111 ulong old_tss_base, struct desc_struct *new_desc) 3112 { 3113 const struct x86_emulate_ops *ops = ctxt->ops; 3114 struct tss_segment_32 tss_seg; 3115 int ret; 3116 u32 new_tss_base = get_desc_base(new_desc); 3117 u32 eip_offset = offsetof(struct tss_segment_32, eip); 3118 u32 ldt_sel_offset = offsetof(struct tss_segment_32, ldt_selector); 3119 3120 ret = ops->read_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg, 3121 &ctxt->exception); 3122 if (ret != X86EMUL_CONTINUE) 3123 return ret; 3124 3125 save_state_to_tss32(ctxt, &tss_seg); 3126 3127 /* Only GP registers and segment selectors are saved */ 3128 ret = ops->write_std(ctxt, old_tss_base + eip_offset, &tss_seg.eip, 3129 ldt_sel_offset - eip_offset, &ctxt->exception); 3130 if (ret != X86EMUL_CONTINUE) 3131 return ret; 3132 3133 ret = ops->read_std(ctxt, new_tss_base, &tss_seg, sizeof tss_seg, 3134 &ctxt->exception); 3135 if (ret != X86EMUL_CONTINUE) 3136 return ret; 3137 3138 if (old_tss_sel != 0xffff) { 3139 tss_seg.prev_task_link = old_tss_sel; 3140 3141 ret = ops->write_std(ctxt, new_tss_base, 3142 &tss_seg.prev_task_link, 3143 sizeof tss_seg.prev_task_link, 3144 &ctxt->exception); 3145 if (ret != X86EMUL_CONTINUE) 3146 return ret; 3147 } 3148 3149 return load_state_from_tss32(ctxt, &tss_seg); 3150 } 3151 3152 static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt, 3153 u16 tss_selector, int idt_index, int reason, 3154 bool has_error_code, u32 error_code) 3155 { 3156 const struct x86_emulate_ops *ops = ctxt->ops; 3157 struct desc_struct curr_tss_desc, next_tss_desc; 3158 int ret; 3159 u16 old_tss_sel = get_segment_selector(ctxt, VCPU_SREG_TR); 3160 ulong old_tss_base = 3161 ops->get_cached_segment_base(ctxt, VCPU_SREG_TR); 3162 u32 desc_limit; 3163 ulong desc_addr, dr7; 3164 3165 /* FIXME: old_tss_base == ~0 ? */ 3166 3167 ret = read_segment_descriptor(ctxt, tss_selector, &next_tss_desc, &desc_addr); 3168 if (ret != X86EMUL_CONTINUE) 3169 return ret; 3170 ret = read_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc, &desc_addr); 3171 if (ret != X86EMUL_CONTINUE) 3172 return ret; 3173 3174 /* FIXME: check that next_tss_desc is tss */ 3175 3176 /* 3177 * Check privileges. The three cases are task switch caused by... 3178 * 3179 * 1. jmp/call/int to task gate: Check against DPL of the task gate 3180 * 2. Exception/IRQ/iret: No check is performed 3181 * 3. jmp/call to TSS/task-gate: No check is performed since the 3182 * hardware checks it before exiting. 3183 */ 3184 if (reason == TASK_SWITCH_GATE) { 3185 if (idt_index != -1) { 3186 /* Software interrupts */ 3187 struct desc_struct task_gate_desc; 3188 int dpl; 3189 3190 ret = read_interrupt_descriptor(ctxt, idt_index, 3191 &task_gate_desc); 3192 if (ret != X86EMUL_CONTINUE) 3193 return ret; 3194 3195 dpl = task_gate_desc.dpl; 3196 if ((tss_selector & 3) > dpl || ops->cpl(ctxt) > dpl) 3197 return emulate_gp(ctxt, (idt_index << 3) | 0x2); 3198 } 3199 } 3200 3201 desc_limit = desc_limit_scaled(&next_tss_desc); 3202 if (!next_tss_desc.p || 3203 ((desc_limit < 0x67 && (next_tss_desc.type & 8)) || 3204 desc_limit < 0x2b)) { 3205 return emulate_ts(ctxt, tss_selector & 0xfffc); 3206 } 3207 3208 if (reason == TASK_SWITCH_IRET || reason == TASK_SWITCH_JMP) { 3209 curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */ 3210 write_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc); 3211 } 3212 3213 if (reason == TASK_SWITCH_IRET) 3214 ctxt->eflags = ctxt->eflags & ~X86_EFLAGS_NT; 3215 3216 /* set back link to prev task only if NT bit is set in eflags 3217 note that old_tss_sel is not used after this point */ 3218 if (reason != TASK_SWITCH_CALL && reason != TASK_SWITCH_GATE) 3219 old_tss_sel = 0xffff; 3220 3221 if (next_tss_desc.type & 8) 3222 ret = task_switch_32(ctxt, tss_selector, old_tss_sel, 3223 old_tss_base, &next_tss_desc); 3224 else 3225 ret = task_switch_16(ctxt, tss_selector, old_tss_sel, 3226 old_tss_base, &next_tss_desc); 3227 if (ret != X86EMUL_CONTINUE) 3228 return ret; 3229 3230 if (reason == TASK_SWITCH_CALL || reason == TASK_SWITCH_GATE) 3231 ctxt->eflags = ctxt->eflags | X86_EFLAGS_NT; 3232 3233 if (reason != TASK_SWITCH_IRET) { 3234 next_tss_desc.type |= (1 << 1); /* set busy flag */ 3235 write_segment_descriptor(ctxt, tss_selector, &next_tss_desc); 3236 } 3237 3238 ops->set_cr(ctxt, 0, ops->get_cr(ctxt, 0) | X86_CR0_TS); 3239 ops->set_segment(ctxt, tss_selector, &next_tss_desc, 0, VCPU_SREG_TR); 3240 3241 if (has_error_code) { 3242 ctxt->op_bytes = ctxt->ad_bytes = (next_tss_desc.type & 8) ? 4 : 2; 3243 ctxt->lock_prefix = 0; 3244 ctxt->src.val = (unsigned long) error_code; 3245 ret = em_push(ctxt); 3246 } 3247 3248 ops->get_dr(ctxt, 7, &dr7); 3249 ops->set_dr(ctxt, 7, dr7 & ~(DR_LOCAL_ENABLE_MASK | DR_LOCAL_SLOWDOWN)); 3250 3251 return ret; 3252 } 3253 3254 int emulator_task_switch(struct x86_emulate_ctxt *ctxt, 3255 u16 tss_selector, int idt_index, int reason, 3256 bool has_error_code, u32 error_code) 3257 { 3258 int rc; 3259 3260 invalidate_registers(ctxt); 3261 ctxt->_eip = ctxt->eip; 3262 ctxt->dst.type = OP_NONE; 3263 3264 rc = emulator_do_task_switch(ctxt, tss_selector, idt_index, reason, 3265 has_error_code, error_code); 3266 3267 if (rc == X86EMUL_CONTINUE) { 3268 ctxt->eip = ctxt->_eip; 3269 writeback_registers(ctxt); 3270 } 3271 3272 return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK; 3273 } 3274 3275 static void string_addr_inc(struct x86_emulate_ctxt *ctxt, int reg, 3276 struct operand *op) 3277 { 3278 int df = (ctxt->eflags & X86_EFLAGS_DF) ? -op->count : op->count; 3279 3280 register_address_increment(ctxt, reg, df * op->bytes); 3281 op->addr.mem.ea = register_address(ctxt, reg); 3282 } 3283 3284 static int em_das(struct x86_emulate_ctxt *ctxt) 3285 { 3286 u8 al, old_al; 3287 bool af, cf, old_cf; 3288 3289 cf = ctxt->eflags & X86_EFLAGS_CF; 3290 al = ctxt->dst.val; 3291 3292 old_al = al; 3293 old_cf = cf; 3294 cf = false; 3295 af = ctxt->eflags & X86_EFLAGS_AF; 3296 if ((al & 0x0f) > 9 || af) { 3297 al -= 6; 3298 cf = old_cf | (al >= 250); 3299 af = true; 3300 } else { 3301 af = false; 3302 } 3303 if (old_al > 0x99 || old_cf) { 3304 al -= 0x60; 3305 cf = true; 3306 } 3307 3308 ctxt->dst.val = al; 3309 /* Set PF, ZF, SF */ 3310 ctxt->src.type = OP_IMM; 3311 ctxt->src.val = 0; 3312 ctxt->src.bytes = 1; 3313 fastop(ctxt, em_or); 3314 ctxt->eflags &= ~(X86_EFLAGS_AF | X86_EFLAGS_CF); 3315 if (cf) 3316 ctxt->eflags |= X86_EFLAGS_CF; 3317 if (af) 3318 ctxt->eflags |= X86_EFLAGS_AF; 3319 return X86EMUL_CONTINUE; 3320 } 3321 3322 static int em_aam(struct x86_emulate_ctxt *ctxt) 3323 { 3324 u8 al, ah; 3325 3326 if (ctxt->src.val == 0) 3327 return emulate_de(ctxt); 3328 3329 al = ctxt->dst.val & 0xff; 3330 ah = al / ctxt->src.val; 3331 al %= ctxt->src.val; 3332 3333 ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al | (ah << 8); 3334 3335 /* Set PF, ZF, SF */ 3336 ctxt->src.type = OP_IMM; 3337 ctxt->src.val = 0; 3338 ctxt->src.bytes = 1; 3339 fastop(ctxt, em_or); 3340 3341 return X86EMUL_CONTINUE; 3342 } 3343 3344 static int em_aad(struct x86_emulate_ctxt *ctxt) 3345 { 3346 u8 al = ctxt->dst.val & 0xff; 3347 u8 ah = (ctxt->dst.val >> 8) & 0xff; 3348 3349 al = (al + (ah * ctxt->src.val)) & 0xff; 3350 3351 ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al; 3352 3353 /* Set PF, ZF, SF */ 3354 ctxt->src.type = OP_IMM; 3355 ctxt->src.val = 0; 3356 ctxt->src.bytes = 1; 3357 fastop(ctxt, em_or); 3358 3359 return X86EMUL_CONTINUE; 3360 } 3361 3362 static int em_call(struct x86_emulate_ctxt *ctxt) 3363 { 3364 int rc; 3365 long rel = ctxt->src.val; 3366 3367 ctxt->src.val = (unsigned long)ctxt->_eip; 3368 rc = jmp_rel(ctxt, rel); 3369 if (rc != X86EMUL_CONTINUE) 3370 return rc; 3371 return em_push(ctxt); 3372 } 3373 3374 static int em_call_far(struct x86_emulate_ctxt *ctxt) 3375 { 3376 u16 sel, old_cs; 3377 ulong old_eip; 3378 int rc; 3379 struct desc_struct old_desc, new_desc; 3380 const struct x86_emulate_ops *ops = ctxt->ops; 3381 int cpl = ctxt->ops->cpl(ctxt); 3382 enum x86emul_mode prev_mode = ctxt->mode; 3383 3384 old_eip = ctxt->_eip; 3385 ops->get_segment(ctxt, &old_cs, &old_desc, NULL, VCPU_SREG_CS); 3386 3387 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2); 3388 rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl, 3389 X86_TRANSFER_CALL_JMP, &new_desc); 3390 if (rc != X86EMUL_CONTINUE) 3391 return rc; 3392 3393 rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc); 3394 if (rc != X86EMUL_CONTINUE) 3395 goto fail; 3396 3397 ctxt->src.val = old_cs; 3398 rc = em_push(ctxt); 3399 if (rc != X86EMUL_CONTINUE) 3400 goto fail; 3401 3402 ctxt->src.val = old_eip; 3403 rc = em_push(ctxt); 3404 /* If we failed, we tainted the memory, but the very least we should 3405 restore cs */ 3406 if (rc != X86EMUL_CONTINUE) { 3407 pr_warn_once("faulting far call emulation tainted memory\n"); 3408 goto fail; 3409 } 3410 return rc; 3411 fail: 3412 ops->set_segment(ctxt, old_cs, &old_desc, 0, VCPU_SREG_CS); 3413 ctxt->mode = prev_mode; 3414 return rc; 3415 3416 } 3417 3418 static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt) 3419 { 3420 int rc; 3421 unsigned long eip; 3422 3423 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes); 3424 if (rc != X86EMUL_CONTINUE) 3425 return rc; 3426 rc = assign_eip_near(ctxt, eip); 3427 if (rc != X86EMUL_CONTINUE) 3428 return rc; 3429 rsp_increment(ctxt, ctxt->src.val); 3430 return X86EMUL_CONTINUE; 3431 } 3432 3433 static int em_xchg(struct x86_emulate_ctxt *ctxt) 3434 { 3435 /* Write back the register source. */ 3436 ctxt->src.val = ctxt->dst.val; 3437 write_register_operand(&ctxt->src); 3438 3439 /* Write back the memory destination with implicit LOCK prefix. */ 3440 ctxt->dst.val = ctxt->src.orig_val; 3441 ctxt->lock_prefix = 1; 3442 return X86EMUL_CONTINUE; 3443 } 3444 3445 static int em_imul_3op(struct x86_emulate_ctxt *ctxt) 3446 { 3447 ctxt->dst.val = ctxt->src2.val; 3448 return fastop(ctxt, em_imul); 3449 } 3450 3451 static int em_cwd(struct x86_emulate_ctxt *ctxt) 3452 { 3453 ctxt->dst.type = OP_REG; 3454 ctxt->dst.bytes = ctxt->src.bytes; 3455 ctxt->dst.addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX); 3456 ctxt->dst.val = ~((ctxt->src.val >> (ctxt->src.bytes * 8 - 1)) - 1); 3457 3458 return X86EMUL_CONTINUE; 3459 } 3460 3461 static int em_rdtsc(struct x86_emulate_ctxt *ctxt) 3462 { 3463 u64 tsc = 0; 3464 3465 ctxt->ops->get_msr(ctxt, MSR_IA32_TSC, &tsc); 3466 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)tsc; 3467 *reg_write(ctxt, VCPU_REGS_RDX) = tsc >> 32; 3468 return X86EMUL_CONTINUE; 3469 } 3470 3471 static int em_rdpmc(struct x86_emulate_ctxt *ctxt) 3472 { 3473 u64 pmc; 3474 3475 if (ctxt->ops->read_pmc(ctxt, reg_read(ctxt, VCPU_REGS_RCX), &pmc)) 3476 return emulate_gp(ctxt, 0); 3477 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)pmc; 3478 *reg_write(ctxt, VCPU_REGS_RDX) = pmc >> 32; 3479 return X86EMUL_CONTINUE; 3480 } 3481 3482 static int em_mov(struct x86_emulate_ctxt *ctxt) 3483 { 3484 memcpy(ctxt->dst.valptr, ctxt->src.valptr, sizeof(ctxt->src.valptr)); 3485 return X86EMUL_CONTINUE; 3486 } 3487 3488 #define FFL(x) bit(X86_FEATURE_##x) 3489 3490 static int em_movbe(struct x86_emulate_ctxt *ctxt) 3491 { 3492 u32 ebx, ecx, edx, eax = 1; 3493 u16 tmp; 3494 3495 /* 3496 * Check MOVBE is set in the guest-visible CPUID leaf. 3497 */ 3498 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); 3499 if (!(ecx & FFL(MOVBE))) 3500 return emulate_ud(ctxt); 3501 3502 switch (ctxt->op_bytes) { 3503 case 2: 3504 /* 3505 * From MOVBE definition: "...When the operand size is 16 bits, 3506 * the upper word of the destination register remains unchanged 3507 * ..." 3508 * 3509 * Both casting ->valptr and ->val to u16 breaks strict aliasing 3510 * rules so we have to do the operation almost per hand. 3511 */ 3512 tmp = (u16)ctxt->src.val; 3513 ctxt->dst.val &= ~0xffffUL; 3514 ctxt->dst.val |= (unsigned long)swab16(tmp); 3515 break; 3516 case 4: 3517 ctxt->dst.val = swab32((u32)ctxt->src.val); 3518 break; 3519 case 8: 3520 ctxt->dst.val = swab64(ctxt->src.val); 3521 break; 3522 default: 3523 BUG(); 3524 } 3525 return X86EMUL_CONTINUE; 3526 } 3527 3528 static int em_cr_write(struct x86_emulate_ctxt *ctxt) 3529 { 3530 if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val)) 3531 return emulate_gp(ctxt, 0); 3532 3533 /* Disable writeback. */ 3534 ctxt->dst.type = OP_NONE; 3535 return X86EMUL_CONTINUE; 3536 } 3537 3538 static int em_dr_write(struct x86_emulate_ctxt *ctxt) 3539 { 3540 unsigned long val; 3541 3542 if (ctxt->mode == X86EMUL_MODE_PROT64) 3543 val = ctxt->src.val & ~0ULL; 3544 else 3545 val = ctxt->src.val & ~0U; 3546 3547 /* #UD condition is already handled. */ 3548 if (ctxt->ops->set_dr(ctxt, ctxt->modrm_reg, val) < 0) 3549 return emulate_gp(ctxt, 0); 3550 3551 /* Disable writeback. */ 3552 ctxt->dst.type = OP_NONE; 3553 return X86EMUL_CONTINUE; 3554 } 3555 3556 static int em_wrmsr(struct x86_emulate_ctxt *ctxt) 3557 { 3558 u64 msr_data; 3559 3560 msr_data = (u32)reg_read(ctxt, VCPU_REGS_RAX) 3561 | ((u64)reg_read(ctxt, VCPU_REGS_RDX) << 32); 3562 if (ctxt->ops->set_msr(ctxt, reg_read(ctxt, VCPU_REGS_RCX), msr_data)) 3563 return emulate_gp(ctxt, 0); 3564 3565 return X86EMUL_CONTINUE; 3566 } 3567 3568 static int em_rdmsr(struct x86_emulate_ctxt *ctxt) 3569 { 3570 u64 msr_data; 3571 3572 if (ctxt->ops->get_msr(ctxt, reg_read(ctxt, VCPU_REGS_RCX), &msr_data)) 3573 return emulate_gp(ctxt, 0); 3574 3575 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)msr_data; 3576 *reg_write(ctxt, VCPU_REGS_RDX) = msr_data >> 32; 3577 return X86EMUL_CONTINUE; 3578 } 3579 3580 static int em_mov_rm_sreg(struct x86_emulate_ctxt *ctxt) 3581 { 3582 if (ctxt->modrm_reg > VCPU_SREG_GS) 3583 return emulate_ud(ctxt); 3584 3585 ctxt->dst.val = get_segment_selector(ctxt, ctxt->modrm_reg); 3586 if (ctxt->dst.bytes == 4 && ctxt->dst.type == OP_MEM) 3587 ctxt->dst.bytes = 2; 3588 return X86EMUL_CONTINUE; 3589 } 3590 3591 static int em_mov_sreg_rm(struct x86_emulate_ctxt *ctxt) 3592 { 3593 u16 sel = ctxt->src.val; 3594 3595 if (ctxt->modrm_reg == VCPU_SREG_CS || ctxt->modrm_reg > VCPU_SREG_GS) 3596 return emulate_ud(ctxt); 3597 3598 if (ctxt->modrm_reg == VCPU_SREG_SS) 3599 ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS; 3600 3601 /* Disable writeback. */ 3602 ctxt->dst.type = OP_NONE; 3603 return load_segment_descriptor(ctxt, sel, ctxt->modrm_reg); 3604 } 3605 3606 static int em_lldt(struct x86_emulate_ctxt *ctxt) 3607 { 3608 u16 sel = ctxt->src.val; 3609 3610 /* Disable writeback. */ 3611 ctxt->dst.type = OP_NONE; 3612 return load_segment_descriptor(ctxt, sel, VCPU_SREG_LDTR); 3613 } 3614 3615 static int em_ltr(struct x86_emulate_ctxt *ctxt) 3616 { 3617 u16 sel = ctxt->src.val; 3618 3619 /* Disable writeback. */ 3620 ctxt->dst.type = OP_NONE; 3621 return load_segment_descriptor(ctxt, sel, VCPU_SREG_TR); 3622 } 3623 3624 static int em_invlpg(struct x86_emulate_ctxt *ctxt) 3625 { 3626 int rc; 3627 ulong linear; 3628 3629 rc = linearize(ctxt, ctxt->src.addr.mem, 1, false, &linear); 3630 if (rc == X86EMUL_CONTINUE) 3631 ctxt->ops->invlpg(ctxt, linear); 3632 /* Disable writeback. */ 3633 ctxt->dst.type = OP_NONE; 3634 return X86EMUL_CONTINUE; 3635 } 3636 3637 static int em_clts(struct x86_emulate_ctxt *ctxt) 3638 { 3639 ulong cr0; 3640 3641 cr0 = ctxt->ops->get_cr(ctxt, 0); 3642 cr0 &= ~X86_CR0_TS; 3643 ctxt->ops->set_cr(ctxt, 0, cr0); 3644 return X86EMUL_CONTINUE; 3645 } 3646 3647 static int em_hypercall(struct x86_emulate_ctxt *ctxt) 3648 { 3649 int rc = ctxt->ops->fix_hypercall(ctxt); 3650 3651 if (rc != X86EMUL_CONTINUE) 3652 return rc; 3653 3654 /* Let the processor re-execute the fixed hypercall */ 3655 ctxt->_eip = ctxt->eip; 3656 /* Disable writeback. */ 3657 ctxt->dst.type = OP_NONE; 3658 return X86EMUL_CONTINUE; 3659 } 3660 3661 static int emulate_store_desc_ptr(struct x86_emulate_ctxt *ctxt, 3662 void (*get)(struct x86_emulate_ctxt *ctxt, 3663 struct desc_ptr *ptr)) 3664 { 3665 struct desc_ptr desc_ptr; 3666 3667 if (ctxt->mode == X86EMUL_MODE_PROT64) 3668 ctxt->op_bytes = 8; 3669 get(ctxt, &desc_ptr); 3670 if (ctxt->op_bytes == 2) { 3671 ctxt->op_bytes = 4; 3672 desc_ptr.address &= 0x00ffffff; 3673 } 3674 /* Disable writeback. */ 3675 ctxt->dst.type = OP_NONE; 3676 return segmented_write(ctxt, ctxt->dst.addr.mem, 3677 &desc_ptr, 2 + ctxt->op_bytes); 3678 } 3679 3680 static int em_sgdt(struct x86_emulate_ctxt *ctxt) 3681 { 3682 return emulate_store_desc_ptr(ctxt, ctxt->ops->get_gdt); 3683 } 3684 3685 static int em_sidt(struct x86_emulate_ctxt *ctxt) 3686 { 3687 return emulate_store_desc_ptr(ctxt, ctxt->ops->get_idt); 3688 } 3689 3690 static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt) 3691 { 3692 struct desc_ptr desc_ptr; 3693 int rc; 3694 3695 if (ctxt->mode == X86EMUL_MODE_PROT64) 3696 ctxt->op_bytes = 8; 3697 rc = read_descriptor(ctxt, ctxt->src.addr.mem, 3698 &desc_ptr.size, &desc_ptr.address, 3699 ctxt->op_bytes); 3700 if (rc != X86EMUL_CONTINUE) 3701 return rc; 3702 if (ctxt->mode == X86EMUL_MODE_PROT64 && 3703 is_noncanonical_address(desc_ptr.address)) 3704 return emulate_gp(ctxt, 0); 3705 if (lgdt) 3706 ctxt->ops->set_gdt(ctxt, &desc_ptr); 3707 else 3708 ctxt->ops->set_idt(ctxt, &desc_ptr); 3709 /* Disable writeback. */ 3710 ctxt->dst.type = OP_NONE; 3711 return X86EMUL_CONTINUE; 3712 } 3713 3714 static int em_lgdt(struct x86_emulate_ctxt *ctxt) 3715 { 3716 return em_lgdt_lidt(ctxt, true); 3717 } 3718 3719 static int em_lidt(struct x86_emulate_ctxt *ctxt) 3720 { 3721 return em_lgdt_lidt(ctxt, false); 3722 } 3723 3724 static int em_smsw(struct x86_emulate_ctxt *ctxt) 3725 { 3726 if (ctxt->dst.type == OP_MEM) 3727 ctxt->dst.bytes = 2; 3728 ctxt->dst.val = ctxt->ops->get_cr(ctxt, 0); 3729 return X86EMUL_CONTINUE; 3730 } 3731 3732 static int em_lmsw(struct x86_emulate_ctxt *ctxt) 3733 { 3734 ctxt->ops->set_cr(ctxt, 0, (ctxt->ops->get_cr(ctxt, 0) & ~0x0eul) 3735 | (ctxt->src.val & 0x0f)); 3736 ctxt->dst.type = OP_NONE; 3737 return X86EMUL_CONTINUE; 3738 } 3739 3740 static int em_loop(struct x86_emulate_ctxt *ctxt) 3741 { 3742 int rc = X86EMUL_CONTINUE; 3743 3744 register_address_increment(ctxt, VCPU_REGS_RCX, -1); 3745 if ((address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) != 0) && 3746 (ctxt->b == 0xe2 || test_cc(ctxt->b ^ 0x5, ctxt->eflags))) 3747 rc = jmp_rel(ctxt, ctxt->src.val); 3748 3749 return rc; 3750 } 3751 3752 static int em_jcxz(struct x86_emulate_ctxt *ctxt) 3753 { 3754 int rc = X86EMUL_CONTINUE; 3755 3756 if (address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) == 0) 3757 rc = jmp_rel(ctxt, ctxt->src.val); 3758 3759 return rc; 3760 } 3761 3762 static int em_in(struct x86_emulate_ctxt *ctxt) 3763 { 3764 if (!pio_in_emulated(ctxt, ctxt->dst.bytes, ctxt->src.val, 3765 &ctxt->dst.val)) 3766 return X86EMUL_IO_NEEDED; 3767 3768 return X86EMUL_CONTINUE; 3769 } 3770 3771 static int em_out(struct x86_emulate_ctxt *ctxt) 3772 { 3773 ctxt->ops->pio_out_emulated(ctxt, ctxt->src.bytes, ctxt->dst.val, 3774 &ctxt->src.val, 1); 3775 /* Disable writeback. */ 3776 ctxt->dst.type = OP_NONE; 3777 return X86EMUL_CONTINUE; 3778 } 3779 3780 static int em_cli(struct x86_emulate_ctxt *ctxt) 3781 { 3782 if (emulator_bad_iopl(ctxt)) 3783 return emulate_gp(ctxt, 0); 3784 3785 ctxt->eflags &= ~X86_EFLAGS_IF; 3786 return X86EMUL_CONTINUE; 3787 } 3788 3789 static int em_sti(struct x86_emulate_ctxt *ctxt) 3790 { 3791 if (emulator_bad_iopl(ctxt)) 3792 return emulate_gp(ctxt, 0); 3793 3794 ctxt->interruptibility = KVM_X86_SHADOW_INT_STI; 3795 ctxt->eflags |= X86_EFLAGS_IF; 3796 return X86EMUL_CONTINUE; 3797 } 3798 3799 static int em_cpuid(struct x86_emulate_ctxt *ctxt) 3800 { 3801 u32 eax, ebx, ecx, edx; 3802 3803 eax = reg_read(ctxt, VCPU_REGS_RAX); 3804 ecx = reg_read(ctxt, VCPU_REGS_RCX); 3805 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); 3806 *reg_write(ctxt, VCPU_REGS_RAX) = eax; 3807 *reg_write(ctxt, VCPU_REGS_RBX) = ebx; 3808 *reg_write(ctxt, VCPU_REGS_RCX) = ecx; 3809 *reg_write(ctxt, VCPU_REGS_RDX) = edx; 3810 return X86EMUL_CONTINUE; 3811 } 3812 3813 static int em_sahf(struct x86_emulate_ctxt *ctxt) 3814 { 3815 u32 flags; 3816 3817 flags = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF | 3818 X86_EFLAGS_SF; 3819 flags &= *reg_rmw(ctxt, VCPU_REGS_RAX) >> 8; 3820 3821 ctxt->eflags &= ~0xffUL; 3822 ctxt->eflags |= flags | X86_EFLAGS_FIXED; 3823 return X86EMUL_CONTINUE; 3824 } 3825 3826 static int em_lahf(struct x86_emulate_ctxt *ctxt) 3827 { 3828 *reg_rmw(ctxt, VCPU_REGS_RAX) &= ~0xff00UL; 3829 *reg_rmw(ctxt, VCPU_REGS_RAX) |= (ctxt->eflags & 0xff) << 8; 3830 return X86EMUL_CONTINUE; 3831 } 3832 3833 static int em_bswap(struct x86_emulate_ctxt *ctxt) 3834 { 3835 switch (ctxt->op_bytes) { 3836 #ifdef CONFIG_X86_64 3837 case 8: 3838 asm("bswap %0" : "+r"(ctxt->dst.val)); 3839 break; 3840 #endif 3841 default: 3842 asm("bswap %0" : "+r"(*(u32 *)&ctxt->dst.val)); 3843 break; 3844 } 3845 return X86EMUL_CONTINUE; 3846 } 3847 3848 static int em_clflush(struct x86_emulate_ctxt *ctxt) 3849 { 3850 /* emulating clflush regardless of cpuid */ 3851 return X86EMUL_CONTINUE; 3852 } 3853 3854 static int em_movsxd(struct x86_emulate_ctxt *ctxt) 3855 { 3856 ctxt->dst.val = (s32) ctxt->src.val; 3857 return X86EMUL_CONTINUE; 3858 } 3859 3860 static bool valid_cr(int nr) 3861 { 3862 switch (nr) { 3863 case 0: 3864 case 2 ... 4: 3865 case 8: 3866 return true; 3867 default: 3868 return false; 3869 } 3870 } 3871 3872 static int check_cr_read(struct x86_emulate_ctxt *ctxt) 3873 { 3874 if (!valid_cr(ctxt->modrm_reg)) 3875 return emulate_ud(ctxt); 3876 3877 return X86EMUL_CONTINUE; 3878 } 3879 3880 static int check_cr_write(struct x86_emulate_ctxt *ctxt) 3881 { 3882 u64 new_val = ctxt->src.val64; 3883 int cr = ctxt->modrm_reg; 3884 u64 efer = 0; 3885 3886 static u64 cr_reserved_bits[] = { 3887 0xffffffff00000000ULL, 3888 0, 0, 0, /* CR3 checked later */ 3889 CR4_RESERVED_BITS, 3890 0, 0, 0, 3891 CR8_RESERVED_BITS, 3892 }; 3893 3894 if (!valid_cr(cr)) 3895 return emulate_ud(ctxt); 3896 3897 if (new_val & cr_reserved_bits[cr]) 3898 return emulate_gp(ctxt, 0); 3899 3900 switch (cr) { 3901 case 0: { 3902 u64 cr4; 3903 if (((new_val & X86_CR0_PG) && !(new_val & X86_CR0_PE)) || 3904 ((new_val & X86_CR0_NW) && !(new_val & X86_CR0_CD))) 3905 return emulate_gp(ctxt, 0); 3906 3907 cr4 = ctxt->ops->get_cr(ctxt, 4); 3908 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 3909 3910 if ((new_val & X86_CR0_PG) && (efer & EFER_LME) && 3911 !(cr4 & X86_CR4_PAE)) 3912 return emulate_gp(ctxt, 0); 3913 3914 break; 3915 } 3916 case 3: { 3917 u64 rsvd = 0; 3918 3919 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 3920 if (efer & EFER_LMA) 3921 rsvd = CR3_L_MODE_RESERVED_BITS & ~CR3_PCID_INVD; 3922 3923 if (new_val & rsvd) 3924 return emulate_gp(ctxt, 0); 3925 3926 break; 3927 } 3928 case 4: { 3929 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 3930 3931 if ((efer & EFER_LMA) && !(new_val & X86_CR4_PAE)) 3932 return emulate_gp(ctxt, 0); 3933 3934 break; 3935 } 3936 } 3937 3938 return X86EMUL_CONTINUE; 3939 } 3940 3941 static int check_dr7_gd(struct x86_emulate_ctxt *ctxt) 3942 { 3943 unsigned long dr7; 3944 3945 ctxt->ops->get_dr(ctxt, 7, &dr7); 3946 3947 /* Check if DR7.Global_Enable is set */ 3948 return dr7 & (1 << 13); 3949 } 3950 3951 static int check_dr_read(struct x86_emulate_ctxt *ctxt) 3952 { 3953 int dr = ctxt->modrm_reg; 3954 u64 cr4; 3955 3956 if (dr > 7) 3957 return emulate_ud(ctxt); 3958 3959 cr4 = ctxt->ops->get_cr(ctxt, 4); 3960 if ((cr4 & X86_CR4_DE) && (dr == 4 || dr == 5)) 3961 return emulate_ud(ctxt); 3962 3963 if (check_dr7_gd(ctxt)) { 3964 ulong dr6; 3965 3966 ctxt->ops->get_dr(ctxt, 6, &dr6); 3967 dr6 &= ~15; 3968 dr6 |= DR6_BD | DR6_RTM; 3969 ctxt->ops->set_dr(ctxt, 6, dr6); 3970 return emulate_db(ctxt); 3971 } 3972 3973 return X86EMUL_CONTINUE; 3974 } 3975 3976 static int check_dr_write(struct x86_emulate_ctxt *ctxt) 3977 { 3978 u64 new_val = ctxt->src.val64; 3979 int dr = ctxt->modrm_reg; 3980 3981 if ((dr == 6 || dr == 7) && (new_val & 0xffffffff00000000ULL)) 3982 return emulate_gp(ctxt, 0); 3983 3984 return check_dr_read(ctxt); 3985 } 3986 3987 static int check_svme(struct x86_emulate_ctxt *ctxt) 3988 { 3989 u64 efer; 3990 3991 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); 3992 3993 if (!(efer & EFER_SVME)) 3994 return emulate_ud(ctxt); 3995 3996 return X86EMUL_CONTINUE; 3997 } 3998 3999 static int check_svme_pa(struct x86_emulate_ctxt *ctxt) 4000 { 4001 u64 rax = reg_read(ctxt, VCPU_REGS_RAX); 4002 4003 /* Valid physical address? */ 4004 if (rax & 0xffff000000000000ULL) 4005 return emulate_gp(ctxt, 0); 4006 4007 return check_svme(ctxt); 4008 } 4009 4010 static int check_rdtsc(struct x86_emulate_ctxt *ctxt) 4011 { 4012 u64 cr4 = ctxt->ops->get_cr(ctxt, 4); 4013 4014 if (cr4 & X86_CR4_TSD && ctxt->ops->cpl(ctxt)) 4015 return emulate_ud(ctxt); 4016 4017 return X86EMUL_CONTINUE; 4018 } 4019 4020 static int check_rdpmc(struct x86_emulate_ctxt *ctxt) 4021 { 4022 u64 cr4 = ctxt->ops->get_cr(ctxt, 4); 4023 u64 rcx = reg_read(ctxt, VCPU_REGS_RCX); 4024 4025 if ((!(cr4 & X86_CR4_PCE) && ctxt->ops->cpl(ctxt)) || 4026 ctxt->ops->check_pmc(ctxt, rcx)) 4027 return emulate_gp(ctxt, 0); 4028 4029 return X86EMUL_CONTINUE; 4030 } 4031 4032 static int check_perm_in(struct x86_emulate_ctxt *ctxt) 4033 { 4034 ctxt->dst.bytes = min(ctxt->dst.bytes, 4u); 4035 if (!emulator_io_permited(ctxt, ctxt->src.val, ctxt->dst.bytes)) 4036 return emulate_gp(ctxt, 0); 4037 4038 return X86EMUL_CONTINUE; 4039 } 4040 4041 static int check_perm_out(struct x86_emulate_ctxt *ctxt) 4042 { 4043 ctxt->src.bytes = min(ctxt->src.bytes, 4u); 4044 if (!emulator_io_permited(ctxt, ctxt->dst.val, ctxt->src.bytes)) 4045 return emulate_gp(ctxt, 0); 4046 4047 return X86EMUL_CONTINUE; 4048 } 4049 4050 #define D(_y) { .flags = (_y) } 4051 #define DI(_y, _i) { .flags = (_y)|Intercept, .intercept = x86_intercept_##_i } 4052 #define DIP(_y, _i, _p) { .flags = (_y)|Intercept|CheckPerm, \ 4053 .intercept = x86_intercept_##_i, .check_perm = (_p) } 4054 #define N D(NotImpl) 4055 #define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) } 4056 #define G(_f, _g) { .flags = ((_f) | Group | ModRM), .u.group = (_g) } 4057 #define GD(_f, _g) { .flags = ((_f) | GroupDual | ModRM), .u.gdual = (_g) } 4058 #define ID(_f, _i) { .flags = ((_f) | InstrDual | ModRM), .u.idual = (_i) } 4059 #define MD(_f, _m) { .flags = ((_f) | ModeDual), .u.mdual = (_m) } 4060 #define E(_f, _e) { .flags = ((_f) | Escape | ModRM), .u.esc = (_e) } 4061 #define I(_f, _e) { .flags = (_f), .u.execute = (_e) } 4062 #define F(_f, _e) { .flags = (_f) | Fastop, .u.fastop = (_e) } 4063 #define II(_f, _e, _i) \ 4064 { .flags = (_f)|Intercept, .u.execute = (_e), .intercept = x86_intercept_##_i } 4065 #define IIP(_f, _e, _i, _p) \ 4066 { .flags = (_f)|Intercept|CheckPerm, .u.execute = (_e), \ 4067 .intercept = x86_intercept_##_i, .check_perm = (_p) } 4068 #define GP(_f, _g) { .flags = ((_f) | Prefix), .u.gprefix = (_g) } 4069 4070 #define D2bv(_f) D((_f) | ByteOp), D(_f) 4071 #define D2bvIP(_f, _i, _p) DIP((_f) | ByteOp, _i, _p), DIP(_f, _i, _p) 4072 #define I2bv(_f, _e) I((_f) | ByteOp, _e), I(_f, _e) 4073 #define F2bv(_f, _e) F((_f) | ByteOp, _e), F(_f, _e) 4074 #define I2bvIP(_f, _e, _i, _p) \ 4075 IIP((_f) | ByteOp, _e, _i, _p), IIP(_f, _e, _i, _p) 4076 4077 #define F6ALU(_f, _e) F2bv((_f) | DstMem | SrcReg | ModRM, _e), \ 4078 F2bv(((_f) | DstReg | SrcMem | ModRM) & ~Lock, _e), \ 4079 F2bv(((_f) & ~Lock) | DstAcc | SrcImm, _e) 4080 4081 static const struct opcode group7_rm0[] = { 4082 N, 4083 I(SrcNone | Priv | EmulateOnUD, em_hypercall), 4084 N, N, N, N, N, N, 4085 }; 4086 4087 static const struct opcode group7_rm1[] = { 4088 DI(SrcNone | Priv, monitor), 4089 DI(SrcNone | Priv, mwait), 4090 N, N, N, N, N, N, 4091 }; 4092 4093 static const struct opcode group7_rm3[] = { 4094 DIP(SrcNone | Prot | Priv, vmrun, check_svme_pa), 4095 II(SrcNone | Prot | EmulateOnUD, em_hypercall, vmmcall), 4096 DIP(SrcNone | Prot | Priv, vmload, check_svme_pa), 4097 DIP(SrcNone | Prot | Priv, vmsave, check_svme_pa), 4098 DIP(SrcNone | Prot | Priv, stgi, check_svme), 4099 DIP(SrcNone | Prot | Priv, clgi, check_svme), 4100 DIP(SrcNone | Prot | Priv, skinit, check_svme), 4101 DIP(SrcNone | Prot | Priv, invlpga, check_svme), 4102 }; 4103 4104 static const struct opcode group7_rm7[] = { 4105 N, 4106 DIP(SrcNone, rdtscp, check_rdtsc), 4107 N, N, N, N, N, N, 4108 }; 4109 4110 static const struct opcode group1[] = { 4111 F(Lock, em_add), 4112 F(Lock | PageTable, em_or), 4113 F(Lock, em_adc), 4114 F(Lock, em_sbb), 4115 F(Lock | PageTable, em_and), 4116 F(Lock, em_sub), 4117 F(Lock, em_xor), 4118 F(NoWrite, em_cmp), 4119 }; 4120 4121 static const struct opcode group1A[] = { 4122 I(DstMem | SrcNone | Mov | Stack | IncSP, em_pop), N, N, N, N, N, N, N, 4123 }; 4124 4125 static const struct opcode group2[] = { 4126 F(DstMem | ModRM, em_rol), 4127 F(DstMem | ModRM, em_ror), 4128 F(DstMem | ModRM, em_rcl), 4129 F(DstMem | ModRM, em_rcr), 4130 F(DstMem | ModRM, em_shl), 4131 F(DstMem | ModRM, em_shr), 4132 F(DstMem | ModRM, em_shl), 4133 F(DstMem | ModRM, em_sar), 4134 }; 4135 4136 static const struct opcode group3[] = { 4137 F(DstMem | SrcImm | NoWrite, em_test), 4138 F(DstMem | SrcImm | NoWrite, em_test), 4139 F(DstMem | SrcNone | Lock, em_not), 4140 F(DstMem | SrcNone | Lock, em_neg), 4141 F(DstXacc | Src2Mem, em_mul_ex), 4142 F(DstXacc | Src2Mem, em_imul_ex), 4143 F(DstXacc | Src2Mem, em_div_ex), 4144 F(DstXacc | Src2Mem, em_idiv_ex), 4145 }; 4146 4147 static const struct opcode group4[] = { 4148 F(ByteOp | DstMem | SrcNone | Lock, em_inc), 4149 F(ByteOp | DstMem | SrcNone | Lock, em_dec), 4150 N, N, N, N, N, N, 4151 }; 4152 4153 static const struct opcode group5[] = { 4154 F(DstMem | SrcNone | Lock, em_inc), 4155 F(DstMem | SrcNone | Lock, em_dec), 4156 I(SrcMem | NearBranch, em_call_near_abs), 4157 I(SrcMemFAddr | ImplicitOps, em_call_far), 4158 I(SrcMem | NearBranch, em_jmp_abs), 4159 I(SrcMemFAddr | ImplicitOps, em_jmp_far), 4160 I(SrcMem | Stack, em_push), D(Undefined), 4161 }; 4162 4163 static const struct opcode group6[] = { 4164 DI(Prot | DstMem, sldt), 4165 DI(Prot | DstMem, str), 4166 II(Prot | Priv | SrcMem16, em_lldt, lldt), 4167 II(Prot | Priv | SrcMem16, em_ltr, ltr), 4168 N, N, N, N, 4169 }; 4170 4171 static const struct group_dual group7 = { { 4172 II(Mov | DstMem, em_sgdt, sgdt), 4173 II(Mov | DstMem, em_sidt, sidt), 4174 II(SrcMem | Priv, em_lgdt, lgdt), 4175 II(SrcMem | Priv, em_lidt, lidt), 4176 II(SrcNone | DstMem | Mov, em_smsw, smsw), N, 4177 II(SrcMem16 | Mov | Priv, em_lmsw, lmsw), 4178 II(SrcMem | ByteOp | Priv | NoAccess, em_invlpg, invlpg), 4179 }, { 4180 EXT(0, group7_rm0), 4181 EXT(0, group7_rm1), 4182 N, EXT(0, group7_rm3), 4183 II(SrcNone | DstMem | Mov, em_smsw, smsw), N, 4184 II(SrcMem16 | Mov | Priv, em_lmsw, lmsw), 4185 EXT(0, group7_rm7), 4186 } }; 4187 4188 static const struct opcode group8[] = { 4189 N, N, N, N, 4190 F(DstMem | SrcImmByte | NoWrite, em_bt), 4191 F(DstMem | SrcImmByte | Lock | PageTable, em_bts), 4192 F(DstMem | SrcImmByte | Lock, em_btr), 4193 F(DstMem | SrcImmByte | Lock | PageTable, em_btc), 4194 }; 4195 4196 static const struct group_dual group9 = { { 4197 N, I(DstMem64 | Lock | PageTable, em_cmpxchg8b), N, N, N, N, N, N, 4198 }, { 4199 N, N, N, N, N, N, N, N, 4200 } }; 4201 4202 static const struct opcode group11[] = { 4203 I(DstMem | SrcImm | Mov | PageTable, em_mov), 4204 X7(D(Undefined)), 4205 }; 4206 4207 static const struct gprefix pfx_0f_ae_7 = { 4208 I(SrcMem | ByteOp, em_clflush), N, N, N, 4209 }; 4210 4211 static const struct group_dual group15 = { { 4212 N, N, N, N, N, N, N, GP(0, &pfx_0f_ae_7), 4213 }, { 4214 N, N, N, N, N, N, N, N, 4215 } }; 4216 4217 static const struct gprefix pfx_0f_6f_0f_7f = { 4218 I(Mmx, em_mov), I(Sse | Aligned, em_mov), N, I(Sse | Unaligned, em_mov), 4219 }; 4220 4221 static const struct instr_dual instr_dual_0f_2b = { 4222 I(0, em_mov), N 4223 }; 4224 4225 static const struct gprefix pfx_0f_2b = { 4226 ID(0, &instr_dual_0f_2b), ID(0, &instr_dual_0f_2b), N, N, 4227 }; 4228 4229 static const struct gprefix pfx_0f_28_0f_29 = { 4230 I(Aligned, em_mov), I(Aligned, em_mov), N, N, 4231 }; 4232 4233 static const struct gprefix pfx_0f_e7 = { 4234 N, I(Sse, em_mov), N, N, 4235 }; 4236 4237 static const struct escape escape_d9 = { { 4238 N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstcw), 4239 }, { 4240 /* 0xC0 - 0xC7 */ 4241 N, N, N, N, N, N, N, N, 4242 /* 0xC8 - 0xCF */ 4243 N, N, N, N, N, N, N, N, 4244 /* 0xD0 - 0xC7 */ 4245 N, N, N, N, N, N, N, N, 4246 /* 0xD8 - 0xDF */ 4247 N, N, N, N, N, N, N, N, 4248 /* 0xE0 - 0xE7 */ 4249 N, N, N, N, N, N, N, N, 4250 /* 0xE8 - 0xEF */ 4251 N, N, N, N, N, N, N, N, 4252 /* 0xF0 - 0xF7 */ 4253 N, N, N, N, N, N, N, N, 4254 /* 0xF8 - 0xFF */ 4255 N, N, N, N, N, N, N, N, 4256 } }; 4257 4258 static const struct escape escape_db = { { 4259 N, N, N, N, N, N, N, N, 4260 }, { 4261 /* 0xC0 - 0xC7 */ 4262 N, N, N, N, N, N, N, N, 4263 /* 0xC8 - 0xCF */ 4264 N, N, N, N, N, N, N, N, 4265 /* 0xD0 - 0xC7 */ 4266 N, N, N, N, N, N, N, N, 4267 /* 0xD8 - 0xDF */ 4268 N, N, N, N, N, N, N, N, 4269 /* 0xE0 - 0xE7 */ 4270 N, N, N, I(ImplicitOps, em_fninit), N, N, N, N, 4271 /* 0xE8 - 0xEF */ 4272 N, N, N, N, N, N, N, N, 4273 /* 0xF0 - 0xF7 */ 4274 N, N, N, N, N, N, N, N, 4275 /* 0xF8 - 0xFF */ 4276 N, N, N, N, N, N, N, N, 4277 } }; 4278 4279 static const struct escape escape_dd = { { 4280 N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstsw), 4281 }, { 4282 /* 0xC0 - 0xC7 */ 4283 N, N, N, N, N, N, N, N, 4284 /* 0xC8 - 0xCF */ 4285 N, N, N, N, N, N, N, N, 4286 /* 0xD0 - 0xC7 */ 4287 N, N, N, N, N, N, N, N, 4288 /* 0xD8 - 0xDF */ 4289 N, N, N, N, N, N, N, N, 4290 /* 0xE0 - 0xE7 */ 4291 N, N, N, N, N, N, N, N, 4292 /* 0xE8 - 0xEF */ 4293 N, N, N, N, N, N, N, N, 4294 /* 0xF0 - 0xF7 */ 4295 N, N, N, N, N, N, N, N, 4296 /* 0xF8 - 0xFF */ 4297 N, N, N, N, N, N, N, N, 4298 } }; 4299 4300 static const struct instr_dual instr_dual_0f_c3 = { 4301 I(DstMem | SrcReg | ModRM | No16 | Mov, em_mov), N 4302 }; 4303 4304 static const struct mode_dual mode_dual_63 = { 4305 N, I(DstReg | SrcMem32 | ModRM | Mov, em_movsxd) 4306 }; 4307 4308 static const struct opcode opcode_table[256] = { 4309 /* 0x00 - 0x07 */ 4310 F6ALU(Lock, em_add), 4311 I(ImplicitOps | Stack | No64 | Src2ES, em_push_sreg), 4312 I(ImplicitOps | Stack | No64 | Src2ES, em_pop_sreg), 4313 /* 0x08 - 0x0F */ 4314 F6ALU(Lock | PageTable, em_or), 4315 I(ImplicitOps | Stack | No64 | Src2CS, em_push_sreg), 4316 N, 4317 /* 0x10 - 0x17 */ 4318 F6ALU(Lock, em_adc), 4319 I(ImplicitOps | Stack | No64 | Src2SS, em_push_sreg), 4320 I(ImplicitOps | Stack | No64 | Src2SS, em_pop_sreg), 4321 /* 0x18 - 0x1F */ 4322 F6ALU(Lock, em_sbb), 4323 I(ImplicitOps | Stack | No64 | Src2DS, em_push_sreg), 4324 I(ImplicitOps | Stack | No64 | Src2DS, em_pop_sreg), 4325 /* 0x20 - 0x27 */ 4326 F6ALU(Lock | PageTable, em_and), N, N, 4327 /* 0x28 - 0x2F */ 4328 F6ALU(Lock, em_sub), N, I(ByteOp | DstAcc | No64, em_das), 4329 /* 0x30 - 0x37 */ 4330 F6ALU(Lock, em_xor), N, N, 4331 /* 0x38 - 0x3F */ 4332 F6ALU(NoWrite, em_cmp), N, N, 4333 /* 0x40 - 0x4F */ 4334 X8(F(DstReg, em_inc)), X8(F(DstReg, em_dec)), 4335 /* 0x50 - 0x57 */ 4336 X8(I(SrcReg | Stack, em_push)), 4337 /* 0x58 - 0x5F */ 4338 X8(I(DstReg | Stack, em_pop)), 4339 /* 0x60 - 0x67 */ 4340 I(ImplicitOps | Stack | No64, em_pusha), 4341 I(ImplicitOps | Stack | No64, em_popa), 4342 N, MD(ModRM, &mode_dual_63), 4343 N, N, N, N, 4344 /* 0x68 - 0x6F */ 4345 I(SrcImm | Mov | Stack, em_push), 4346 I(DstReg | SrcMem | ModRM | Src2Imm, em_imul_3op), 4347 I(SrcImmByte | Mov | Stack, em_push), 4348 I(DstReg | SrcMem | ModRM | Src2ImmByte, em_imul_3op), 4349 I2bvIP(DstDI | SrcDX | Mov | String | Unaligned, em_in, ins, check_perm_in), /* insb, insw/insd */ 4350 I2bvIP(SrcSI | DstDX | String, em_out, outs, check_perm_out), /* outsb, outsw/outsd */ 4351 /* 0x70 - 0x7F */ 4352 X16(D(SrcImmByte | NearBranch)), 4353 /* 0x80 - 0x87 */ 4354 G(ByteOp | DstMem | SrcImm, group1), 4355 G(DstMem | SrcImm, group1), 4356 G(ByteOp | DstMem | SrcImm | No64, group1), 4357 G(DstMem | SrcImmByte, group1), 4358 F2bv(DstMem | SrcReg | ModRM | NoWrite, em_test), 4359 I2bv(DstMem | SrcReg | ModRM | Lock | PageTable, em_xchg), 4360 /* 0x88 - 0x8F */ 4361 I2bv(DstMem | SrcReg | ModRM | Mov | PageTable, em_mov), 4362 I2bv(DstReg | SrcMem | ModRM | Mov, em_mov), 4363 I(DstMem | SrcNone | ModRM | Mov | PageTable, em_mov_rm_sreg), 4364 D(ModRM | SrcMem | NoAccess | DstReg), 4365 I(ImplicitOps | SrcMem16 | ModRM, em_mov_sreg_rm), 4366 G(0, group1A), 4367 /* 0x90 - 0x97 */ 4368 DI(SrcAcc | DstReg, pause), X7(D(SrcAcc | DstReg)), 4369 /* 0x98 - 0x9F */ 4370 D(DstAcc | SrcNone), I(ImplicitOps | SrcAcc, em_cwd), 4371 I(SrcImmFAddr | No64, em_call_far), N, 4372 II(ImplicitOps | Stack, em_pushf, pushf), 4373 II(ImplicitOps | Stack, em_popf, popf), 4374 I(ImplicitOps, em_sahf), I(ImplicitOps, em_lahf), 4375 /* 0xA0 - 0xA7 */ 4376 I2bv(DstAcc | SrcMem | Mov | MemAbs, em_mov), 4377 I2bv(DstMem | SrcAcc | Mov | MemAbs | PageTable, em_mov), 4378 I2bv(SrcSI | DstDI | Mov | String, em_mov), 4379 F2bv(SrcSI | DstDI | String | NoWrite, em_cmp_r), 4380 /* 0xA8 - 0xAF */ 4381 F2bv(DstAcc | SrcImm | NoWrite, em_test), 4382 I2bv(SrcAcc | DstDI | Mov | String, em_mov), 4383 I2bv(SrcSI | DstAcc | Mov | String, em_mov), 4384 F2bv(SrcAcc | DstDI | String | NoWrite, em_cmp_r), 4385 /* 0xB0 - 0xB7 */ 4386 X8(I(ByteOp | DstReg | SrcImm | Mov, em_mov)), 4387 /* 0xB8 - 0xBF */ 4388 X8(I(DstReg | SrcImm64 | Mov, em_mov)), 4389 /* 0xC0 - 0xC7 */ 4390 G(ByteOp | Src2ImmByte, group2), G(Src2ImmByte, group2), 4391 I(ImplicitOps | NearBranch | SrcImmU16, em_ret_near_imm), 4392 I(ImplicitOps | NearBranch, em_ret), 4393 I(DstReg | SrcMemFAddr | ModRM | No64 | Src2ES, em_lseg), 4394 I(DstReg | SrcMemFAddr | ModRM | No64 | Src2DS, em_lseg), 4395 G(ByteOp, group11), G(0, group11), 4396 /* 0xC8 - 0xCF */ 4397 I(Stack | SrcImmU16 | Src2ImmByte, em_enter), I(Stack, em_leave), 4398 I(ImplicitOps | SrcImmU16, em_ret_far_imm), 4399 I(ImplicitOps, em_ret_far), 4400 D(ImplicitOps), DI(SrcImmByte, intn), 4401 D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret), 4402 /* 0xD0 - 0xD7 */ 4403 G(Src2One | ByteOp, group2), G(Src2One, group2), 4404 G(Src2CL | ByteOp, group2), G(Src2CL, group2), 4405 I(DstAcc | SrcImmUByte | No64, em_aam), 4406 I(DstAcc | SrcImmUByte | No64, em_aad), 4407 F(DstAcc | ByteOp | No64, em_salc), 4408 I(DstAcc | SrcXLat | ByteOp, em_mov), 4409 /* 0xD8 - 0xDF */ 4410 N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N, 4411 /* 0xE0 - 0xE7 */ 4412 X3(I(SrcImmByte | NearBranch, em_loop)), 4413 I(SrcImmByte | NearBranch, em_jcxz), 4414 I2bvIP(SrcImmUByte | DstAcc, em_in, in, check_perm_in), 4415 I2bvIP(SrcAcc | DstImmUByte, em_out, out, check_perm_out), 4416 /* 0xE8 - 0xEF */ 4417 I(SrcImm | NearBranch, em_call), D(SrcImm | ImplicitOps | NearBranch), 4418 I(SrcImmFAddr | No64, em_jmp_far), 4419 D(SrcImmByte | ImplicitOps | NearBranch), 4420 I2bvIP(SrcDX | DstAcc, em_in, in, check_perm_in), 4421 I2bvIP(SrcAcc | DstDX, em_out, out, check_perm_out), 4422 /* 0xF0 - 0xF7 */ 4423 N, DI(ImplicitOps, icebp), N, N, 4424 DI(ImplicitOps | Priv, hlt), D(ImplicitOps), 4425 G(ByteOp, group3), G(0, group3), 4426 /* 0xF8 - 0xFF */ 4427 D(ImplicitOps), D(ImplicitOps), 4428 I(ImplicitOps, em_cli), I(ImplicitOps, em_sti), 4429 D(ImplicitOps), D(ImplicitOps), G(0, group4), G(0, group5), 4430 }; 4431 4432 static const struct opcode twobyte_table[256] = { 4433 /* 0x00 - 0x0F */ 4434 G(0, group6), GD(0, &group7), N, N, 4435 N, I(ImplicitOps | EmulateOnUD, em_syscall), 4436 II(ImplicitOps | Priv, em_clts, clts), N, 4437 DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N, 4438 N, D(ImplicitOps | ModRM | SrcMem | NoAccess), N, N, 4439 /* 0x10 - 0x1F */ 4440 N, N, N, N, N, N, N, N, 4441 D(ImplicitOps | ModRM | SrcMem | NoAccess), 4442 N, N, N, N, N, N, D(ImplicitOps | ModRM | SrcMem | NoAccess), 4443 /* 0x20 - 0x2F */ 4444 DIP(ModRM | DstMem | Priv | Op3264 | NoMod, cr_read, check_cr_read), 4445 DIP(ModRM | DstMem | Priv | Op3264 | NoMod, dr_read, check_dr_read), 4446 IIP(ModRM | SrcMem | Priv | Op3264 | NoMod, em_cr_write, cr_write, 4447 check_cr_write), 4448 IIP(ModRM | SrcMem | Priv | Op3264 | NoMod, em_dr_write, dr_write, 4449 check_dr_write), 4450 N, N, N, N, 4451 GP(ModRM | DstReg | SrcMem | Mov | Sse, &pfx_0f_28_0f_29), 4452 GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_28_0f_29), 4453 N, GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_2b), 4454 N, N, N, N, 4455 /* 0x30 - 0x3F */ 4456 II(ImplicitOps | Priv, em_wrmsr, wrmsr), 4457 IIP(ImplicitOps, em_rdtsc, rdtsc, check_rdtsc), 4458 II(ImplicitOps | Priv, em_rdmsr, rdmsr), 4459 IIP(ImplicitOps, em_rdpmc, rdpmc, check_rdpmc), 4460 I(ImplicitOps | EmulateOnUD, em_sysenter), 4461 I(ImplicitOps | Priv | EmulateOnUD, em_sysexit), 4462 N, N, 4463 N, N, N, N, N, N, N, N, 4464 /* 0x40 - 0x4F */ 4465 X16(D(DstReg | SrcMem | ModRM)), 4466 /* 0x50 - 0x5F */ 4467 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, 4468 /* 0x60 - 0x6F */ 4469 N, N, N, N, 4470 N, N, N, N, 4471 N, N, N, N, 4472 N, N, N, GP(SrcMem | DstReg | ModRM | Mov, &pfx_0f_6f_0f_7f), 4473 /* 0x70 - 0x7F */ 4474 N, N, N, N, 4475 N, N, N, N, 4476 N, N, N, N, 4477 N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_6f_0f_7f), 4478 /* 0x80 - 0x8F */ 4479 X16(D(SrcImm | NearBranch)), 4480 /* 0x90 - 0x9F */ 4481 X16(D(ByteOp | DstMem | SrcNone | ModRM| Mov)), 4482 /* 0xA0 - 0xA7 */ 4483 I(Stack | Src2FS, em_push_sreg), I(Stack | Src2FS, em_pop_sreg), 4484 II(ImplicitOps, em_cpuid, cpuid), 4485 F(DstMem | SrcReg | ModRM | BitOp | NoWrite, em_bt), 4486 F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shld), 4487 F(DstMem | SrcReg | Src2CL | ModRM, em_shld), N, N, 4488 /* 0xA8 - 0xAF */ 4489 I(Stack | Src2GS, em_push_sreg), I(Stack | Src2GS, em_pop_sreg), 4490 II(EmulateOnUD | ImplicitOps, em_rsm, rsm), 4491 F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_bts), 4492 F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shrd), 4493 F(DstMem | SrcReg | Src2CL | ModRM, em_shrd), 4494 GD(0, &group15), F(DstReg | SrcMem | ModRM, em_imul), 4495 /* 0xB0 - 0xB7 */ 4496 I2bv(DstMem | SrcReg | ModRM | Lock | PageTable | SrcWrite, em_cmpxchg), 4497 I(DstReg | SrcMemFAddr | ModRM | Src2SS, em_lseg), 4498 F(DstMem | SrcReg | ModRM | BitOp | Lock, em_btr), 4499 I(DstReg | SrcMemFAddr | ModRM | Src2FS, em_lseg), 4500 I(DstReg | SrcMemFAddr | ModRM | Src2GS, em_lseg), 4501 D(DstReg | SrcMem8 | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov), 4502 /* 0xB8 - 0xBF */ 4503 N, N, 4504 G(BitOp, group8), 4505 F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_btc), 4506 I(DstReg | SrcMem | ModRM, em_bsf_c), 4507 I(DstReg | SrcMem | ModRM, em_bsr_c), 4508 D(DstReg | SrcMem8 | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov), 4509 /* 0xC0 - 0xC7 */ 4510 F2bv(DstMem | SrcReg | ModRM | SrcWrite | Lock, em_xadd), 4511 N, ID(0, &instr_dual_0f_c3), 4512 N, N, N, GD(0, &group9), 4513 /* 0xC8 - 0xCF */ 4514 X8(I(DstReg, em_bswap)), 4515 /* 0xD0 - 0xDF */ 4516 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, 4517 /* 0xE0 - 0xEF */ 4518 N, N, N, N, N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_e7), 4519 N, N, N, N, N, N, N, N, 4520 /* 0xF0 - 0xFF */ 4521 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N 4522 }; 4523 4524 static const struct instr_dual instr_dual_0f_38_f0 = { 4525 I(DstReg | SrcMem | Mov, em_movbe), N 4526 }; 4527 4528 static const struct instr_dual instr_dual_0f_38_f1 = { 4529 I(DstMem | SrcReg | Mov, em_movbe), N 4530 }; 4531 4532 static const struct gprefix three_byte_0f_38_f0 = { 4533 ID(0, &instr_dual_0f_38_f0), N, N, N 4534 }; 4535 4536 static const struct gprefix three_byte_0f_38_f1 = { 4537 ID(0, &instr_dual_0f_38_f1), N, N, N 4538 }; 4539 4540 /* 4541 * Insns below are selected by the prefix which indexed by the third opcode 4542 * byte. 4543 */ 4544 static const struct opcode opcode_map_0f_38[256] = { 4545 /* 0x00 - 0x7f */ 4546 X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), 4547 /* 0x80 - 0xef */ 4548 X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), 4549 /* 0xf0 - 0xf1 */ 4550 GP(EmulateOnUD | ModRM, &three_byte_0f_38_f0), 4551 GP(EmulateOnUD | ModRM, &three_byte_0f_38_f1), 4552 /* 0xf2 - 0xff */ 4553 N, N, X4(N), X8(N) 4554 }; 4555 4556 #undef D 4557 #undef N 4558 #undef G 4559 #undef GD 4560 #undef I 4561 #undef GP 4562 #undef EXT 4563 #undef MD 4564 #undef ID 4565 4566 #undef D2bv 4567 #undef D2bvIP 4568 #undef I2bv 4569 #undef I2bvIP 4570 #undef I6ALU 4571 4572 static unsigned imm_size(struct x86_emulate_ctxt *ctxt) 4573 { 4574 unsigned size; 4575 4576 size = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4577 if (size == 8) 4578 size = 4; 4579 return size; 4580 } 4581 4582 static int decode_imm(struct x86_emulate_ctxt *ctxt, struct operand *op, 4583 unsigned size, bool sign_extension) 4584 { 4585 int rc = X86EMUL_CONTINUE; 4586 4587 op->type = OP_IMM; 4588 op->bytes = size; 4589 op->addr.mem.ea = ctxt->_eip; 4590 /* NB. Immediates are sign-extended as necessary. */ 4591 switch (op->bytes) { 4592 case 1: 4593 op->val = insn_fetch(s8, ctxt); 4594 break; 4595 case 2: 4596 op->val = insn_fetch(s16, ctxt); 4597 break; 4598 case 4: 4599 op->val = insn_fetch(s32, ctxt); 4600 break; 4601 case 8: 4602 op->val = insn_fetch(s64, ctxt); 4603 break; 4604 } 4605 if (!sign_extension) { 4606 switch (op->bytes) { 4607 case 1: 4608 op->val &= 0xff; 4609 break; 4610 case 2: 4611 op->val &= 0xffff; 4612 break; 4613 case 4: 4614 op->val &= 0xffffffff; 4615 break; 4616 } 4617 } 4618 done: 4619 return rc; 4620 } 4621 4622 static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op, 4623 unsigned d) 4624 { 4625 int rc = X86EMUL_CONTINUE; 4626 4627 switch (d) { 4628 case OpReg: 4629 decode_register_operand(ctxt, op); 4630 break; 4631 case OpImmUByte: 4632 rc = decode_imm(ctxt, op, 1, false); 4633 break; 4634 case OpMem: 4635 ctxt->memop.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4636 mem_common: 4637 *op = ctxt->memop; 4638 ctxt->memopp = op; 4639 if (ctxt->d & BitOp) 4640 fetch_bit_operand(ctxt); 4641 op->orig_val = op->val; 4642 break; 4643 case OpMem64: 4644 ctxt->memop.bytes = (ctxt->op_bytes == 8) ? 16 : 8; 4645 goto mem_common; 4646 case OpAcc: 4647 op->type = OP_REG; 4648 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4649 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); 4650 fetch_register_operand(op); 4651 op->orig_val = op->val; 4652 break; 4653 case OpAccLo: 4654 op->type = OP_REG; 4655 op->bytes = (ctxt->d & ByteOp) ? 2 : ctxt->op_bytes; 4656 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); 4657 fetch_register_operand(op); 4658 op->orig_val = op->val; 4659 break; 4660 case OpAccHi: 4661 if (ctxt->d & ByteOp) { 4662 op->type = OP_NONE; 4663 break; 4664 } 4665 op->type = OP_REG; 4666 op->bytes = ctxt->op_bytes; 4667 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX); 4668 fetch_register_operand(op); 4669 op->orig_val = op->val; 4670 break; 4671 case OpDI: 4672 op->type = OP_MEM; 4673 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4674 op->addr.mem.ea = 4675 register_address(ctxt, VCPU_REGS_RDI); 4676 op->addr.mem.seg = VCPU_SREG_ES; 4677 op->val = 0; 4678 op->count = 1; 4679 break; 4680 case OpDX: 4681 op->type = OP_REG; 4682 op->bytes = 2; 4683 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX); 4684 fetch_register_operand(op); 4685 break; 4686 case OpCL: 4687 op->type = OP_IMM; 4688 op->bytes = 1; 4689 op->val = reg_read(ctxt, VCPU_REGS_RCX) & 0xff; 4690 break; 4691 case OpImmByte: 4692 rc = decode_imm(ctxt, op, 1, true); 4693 break; 4694 case OpOne: 4695 op->type = OP_IMM; 4696 op->bytes = 1; 4697 op->val = 1; 4698 break; 4699 case OpImm: 4700 rc = decode_imm(ctxt, op, imm_size(ctxt), true); 4701 break; 4702 case OpImm64: 4703 rc = decode_imm(ctxt, op, ctxt->op_bytes, true); 4704 break; 4705 case OpMem8: 4706 ctxt->memop.bytes = 1; 4707 if (ctxt->memop.type == OP_REG) { 4708 ctxt->memop.addr.reg = decode_register(ctxt, 4709 ctxt->modrm_rm, true); 4710 fetch_register_operand(&ctxt->memop); 4711 } 4712 goto mem_common; 4713 case OpMem16: 4714 ctxt->memop.bytes = 2; 4715 goto mem_common; 4716 case OpMem32: 4717 ctxt->memop.bytes = 4; 4718 goto mem_common; 4719 case OpImmU16: 4720 rc = decode_imm(ctxt, op, 2, false); 4721 break; 4722 case OpImmU: 4723 rc = decode_imm(ctxt, op, imm_size(ctxt), false); 4724 break; 4725 case OpSI: 4726 op->type = OP_MEM; 4727 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4728 op->addr.mem.ea = 4729 register_address(ctxt, VCPU_REGS_RSI); 4730 op->addr.mem.seg = ctxt->seg_override; 4731 op->val = 0; 4732 op->count = 1; 4733 break; 4734 case OpXLat: 4735 op->type = OP_MEM; 4736 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; 4737 op->addr.mem.ea = 4738 address_mask(ctxt, 4739 reg_read(ctxt, VCPU_REGS_RBX) + 4740 (reg_read(ctxt, VCPU_REGS_RAX) & 0xff)); 4741 op->addr.mem.seg = ctxt->seg_override; 4742 op->val = 0; 4743 break; 4744 case OpImmFAddr: 4745 op->type = OP_IMM; 4746 op->addr.mem.ea = ctxt->_eip; 4747 op->bytes = ctxt->op_bytes + 2; 4748 insn_fetch_arr(op->valptr, op->bytes, ctxt); 4749 break; 4750 case OpMemFAddr: 4751 ctxt->memop.bytes = ctxt->op_bytes + 2; 4752 goto mem_common; 4753 case OpES: 4754 op->type = OP_IMM; 4755 op->val = VCPU_SREG_ES; 4756 break; 4757 case OpCS: 4758 op->type = OP_IMM; 4759 op->val = VCPU_SREG_CS; 4760 break; 4761 case OpSS: 4762 op->type = OP_IMM; 4763 op->val = VCPU_SREG_SS; 4764 break; 4765 case OpDS: 4766 op->type = OP_IMM; 4767 op->val = VCPU_SREG_DS; 4768 break; 4769 case OpFS: 4770 op->type = OP_IMM; 4771 op->val = VCPU_SREG_FS; 4772 break; 4773 case OpGS: 4774 op->type = OP_IMM; 4775 op->val = VCPU_SREG_GS; 4776 break; 4777 case OpImplicit: 4778 /* Special instructions do their own operand decoding. */ 4779 default: 4780 op->type = OP_NONE; /* Disable writeback. */ 4781 break; 4782 } 4783 4784 done: 4785 return rc; 4786 } 4787 4788 int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 4789 { 4790 int rc = X86EMUL_CONTINUE; 4791 int mode = ctxt->mode; 4792 int def_op_bytes, def_ad_bytes, goffset, simd_prefix; 4793 bool op_prefix = false; 4794 bool has_seg_override = false; 4795 struct opcode opcode; 4796 4797 ctxt->memop.type = OP_NONE; 4798 ctxt->memopp = NULL; 4799 ctxt->_eip = ctxt->eip; 4800 ctxt->fetch.ptr = ctxt->fetch.data; 4801 ctxt->fetch.end = ctxt->fetch.data + insn_len; 4802 ctxt->opcode_len = 1; 4803 if (insn_len > 0) 4804 memcpy(ctxt->fetch.data, insn, insn_len); 4805 else { 4806 rc = __do_insn_fetch_bytes(ctxt, 1); 4807 if (rc != X86EMUL_CONTINUE) 4808 return rc; 4809 } 4810 4811 switch (mode) { 4812 case X86EMUL_MODE_REAL: 4813 case X86EMUL_MODE_VM86: 4814 case X86EMUL_MODE_PROT16: 4815 def_op_bytes = def_ad_bytes = 2; 4816 break; 4817 case X86EMUL_MODE_PROT32: 4818 def_op_bytes = def_ad_bytes = 4; 4819 break; 4820 #ifdef CONFIG_X86_64 4821 case X86EMUL_MODE_PROT64: 4822 def_op_bytes = 4; 4823 def_ad_bytes = 8; 4824 break; 4825 #endif 4826 default: 4827 return EMULATION_FAILED; 4828 } 4829 4830 ctxt->op_bytes = def_op_bytes; 4831 ctxt->ad_bytes = def_ad_bytes; 4832 4833 /* Legacy prefixes. */ 4834 for (;;) { 4835 switch (ctxt->b = insn_fetch(u8, ctxt)) { 4836 case 0x66: /* operand-size override */ 4837 op_prefix = true; 4838 /* switch between 2/4 bytes */ 4839 ctxt->op_bytes = def_op_bytes ^ 6; 4840 break; 4841 case 0x67: /* address-size override */ 4842 if (mode == X86EMUL_MODE_PROT64) 4843 /* switch between 4/8 bytes */ 4844 ctxt->ad_bytes = def_ad_bytes ^ 12; 4845 else 4846 /* switch between 2/4 bytes */ 4847 ctxt->ad_bytes = def_ad_bytes ^ 6; 4848 break; 4849 case 0x26: /* ES override */ 4850 case 0x2e: /* CS override */ 4851 case 0x36: /* SS override */ 4852 case 0x3e: /* DS override */ 4853 has_seg_override = true; 4854 ctxt->seg_override = (ctxt->b >> 3) & 3; 4855 break; 4856 case 0x64: /* FS override */ 4857 case 0x65: /* GS override */ 4858 has_seg_override = true; 4859 ctxt->seg_override = ctxt->b & 7; 4860 break; 4861 case 0x40 ... 0x4f: /* REX */ 4862 if (mode != X86EMUL_MODE_PROT64) 4863 goto done_prefixes; 4864 ctxt->rex_prefix = ctxt->b; 4865 continue; 4866 case 0xf0: /* LOCK */ 4867 ctxt->lock_prefix = 1; 4868 break; 4869 case 0xf2: /* REPNE/REPNZ */ 4870 case 0xf3: /* REP/REPE/REPZ */ 4871 ctxt->rep_prefix = ctxt->b; 4872 break; 4873 default: 4874 goto done_prefixes; 4875 } 4876 4877 /* Any legacy prefix after a REX prefix nullifies its effect. */ 4878 4879 ctxt->rex_prefix = 0; 4880 } 4881 4882 done_prefixes: 4883 4884 /* REX prefix. */ 4885 if (ctxt->rex_prefix & 8) 4886 ctxt->op_bytes = 8; /* REX.W */ 4887 4888 /* Opcode byte(s). */ 4889 opcode = opcode_table[ctxt->b]; 4890 /* Two-byte opcode? */ 4891 if (ctxt->b == 0x0f) { 4892 ctxt->opcode_len = 2; 4893 ctxt->b = insn_fetch(u8, ctxt); 4894 opcode = twobyte_table[ctxt->b]; 4895 4896 /* 0F_38 opcode map */ 4897 if (ctxt->b == 0x38) { 4898 ctxt->opcode_len = 3; 4899 ctxt->b = insn_fetch(u8, ctxt); 4900 opcode = opcode_map_0f_38[ctxt->b]; 4901 } 4902 } 4903 ctxt->d = opcode.flags; 4904 4905 if (ctxt->d & ModRM) 4906 ctxt->modrm = insn_fetch(u8, ctxt); 4907 4908 /* vex-prefix instructions are not implemented */ 4909 if (ctxt->opcode_len == 1 && (ctxt->b == 0xc5 || ctxt->b == 0xc4) && 4910 (mode == X86EMUL_MODE_PROT64 || (ctxt->modrm & 0xc0) == 0xc0)) { 4911 ctxt->d = NotImpl; 4912 } 4913 4914 while (ctxt->d & GroupMask) { 4915 switch (ctxt->d & GroupMask) { 4916 case Group: 4917 goffset = (ctxt->modrm >> 3) & 7; 4918 opcode = opcode.u.group[goffset]; 4919 break; 4920 case GroupDual: 4921 goffset = (ctxt->modrm >> 3) & 7; 4922 if ((ctxt->modrm >> 6) == 3) 4923 opcode = opcode.u.gdual->mod3[goffset]; 4924 else 4925 opcode = opcode.u.gdual->mod012[goffset]; 4926 break; 4927 case RMExt: 4928 goffset = ctxt->modrm & 7; 4929 opcode = opcode.u.group[goffset]; 4930 break; 4931 case Prefix: 4932 if (ctxt->rep_prefix && op_prefix) 4933 return EMULATION_FAILED; 4934 simd_prefix = op_prefix ? 0x66 : ctxt->rep_prefix; 4935 switch (simd_prefix) { 4936 case 0x00: opcode = opcode.u.gprefix->pfx_no; break; 4937 case 0x66: opcode = opcode.u.gprefix->pfx_66; break; 4938 case 0xf2: opcode = opcode.u.gprefix->pfx_f2; break; 4939 case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break; 4940 } 4941 break; 4942 case Escape: 4943 if (ctxt->modrm > 0xbf) 4944 opcode = opcode.u.esc->high[ctxt->modrm - 0xc0]; 4945 else 4946 opcode = opcode.u.esc->op[(ctxt->modrm >> 3) & 7]; 4947 break; 4948 case InstrDual: 4949 if ((ctxt->modrm >> 6) == 3) 4950 opcode = opcode.u.idual->mod3; 4951 else 4952 opcode = opcode.u.idual->mod012; 4953 break; 4954 case ModeDual: 4955 if (ctxt->mode == X86EMUL_MODE_PROT64) 4956 opcode = opcode.u.mdual->mode64; 4957 else 4958 opcode = opcode.u.mdual->mode32; 4959 break; 4960 default: 4961 return EMULATION_FAILED; 4962 } 4963 4964 ctxt->d &= ~(u64)GroupMask; 4965 ctxt->d |= opcode.flags; 4966 } 4967 4968 /* Unrecognised? */ 4969 if (ctxt->d == 0) 4970 return EMULATION_FAILED; 4971 4972 ctxt->execute = opcode.u.execute; 4973 4974 if (unlikely(ctxt->ud) && likely(!(ctxt->d & EmulateOnUD))) 4975 return EMULATION_FAILED; 4976 4977 if (unlikely(ctxt->d & 4978 (NotImpl|Stack|Op3264|Sse|Mmx|Intercept|CheckPerm|NearBranch| 4979 No16))) { 4980 /* 4981 * These are copied unconditionally here, and checked unconditionally 4982 * in x86_emulate_insn. 4983 */ 4984 ctxt->check_perm = opcode.check_perm; 4985 ctxt->intercept = opcode.intercept; 4986 4987 if (ctxt->d & NotImpl) 4988 return EMULATION_FAILED; 4989 4990 if (mode == X86EMUL_MODE_PROT64) { 4991 if (ctxt->op_bytes == 4 && (ctxt->d & Stack)) 4992 ctxt->op_bytes = 8; 4993 else if (ctxt->d & NearBranch) 4994 ctxt->op_bytes = 8; 4995 } 4996 4997 if (ctxt->d & Op3264) { 4998 if (mode == X86EMUL_MODE_PROT64) 4999 ctxt->op_bytes = 8; 5000 else 5001 ctxt->op_bytes = 4; 5002 } 5003 5004 if ((ctxt->d & No16) && ctxt->op_bytes == 2) 5005 ctxt->op_bytes = 4; 5006 5007 if (ctxt->d & Sse) 5008 ctxt->op_bytes = 16; 5009 else if (ctxt->d & Mmx) 5010 ctxt->op_bytes = 8; 5011 } 5012 5013 /* ModRM and SIB bytes. */ 5014 if (ctxt->d & ModRM) { 5015 rc = decode_modrm(ctxt, &ctxt->memop); 5016 if (!has_seg_override) { 5017 has_seg_override = true; 5018 ctxt->seg_override = ctxt->modrm_seg; 5019 } 5020 } else if (ctxt->d & MemAbs) 5021 rc = decode_abs(ctxt, &ctxt->memop); 5022 if (rc != X86EMUL_CONTINUE) 5023 goto done; 5024 5025 if (!has_seg_override) 5026 ctxt->seg_override = VCPU_SREG_DS; 5027 5028 ctxt->memop.addr.mem.seg = ctxt->seg_override; 5029 5030 /* 5031 * Decode and fetch the source operand: register, memory 5032 * or immediate. 5033 */ 5034 rc = decode_operand(ctxt, &ctxt->src, (ctxt->d >> SrcShift) & OpMask); 5035 if (rc != X86EMUL_CONTINUE) 5036 goto done; 5037 5038 /* 5039 * Decode and fetch the second source operand: register, memory 5040 * or immediate. 5041 */ 5042 rc = decode_operand(ctxt, &ctxt->src2, (ctxt->d >> Src2Shift) & OpMask); 5043 if (rc != X86EMUL_CONTINUE) 5044 goto done; 5045 5046 /* Decode and fetch the destination operand: register or memory. */ 5047 rc = decode_operand(ctxt, &ctxt->dst, (ctxt->d >> DstShift) & OpMask); 5048 5049 if (ctxt->rip_relative) 5050 ctxt->memopp->addr.mem.ea = address_mask(ctxt, 5051 ctxt->memopp->addr.mem.ea + ctxt->_eip); 5052 5053 done: 5054 return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK; 5055 } 5056 5057 bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt) 5058 { 5059 return ctxt->d & PageTable; 5060 } 5061 5062 static bool string_insn_completed(struct x86_emulate_ctxt *ctxt) 5063 { 5064 /* The second termination condition only applies for REPE 5065 * and REPNE. Test if the repeat string operation prefix is 5066 * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the 5067 * corresponding termination condition according to: 5068 * - if REPE/REPZ and ZF = 0 then done 5069 * - if REPNE/REPNZ and ZF = 1 then done 5070 */ 5071 if (((ctxt->b == 0xa6) || (ctxt->b == 0xa7) || 5072 (ctxt->b == 0xae) || (ctxt->b == 0xaf)) 5073 && (((ctxt->rep_prefix == REPE_PREFIX) && 5074 ((ctxt->eflags & X86_EFLAGS_ZF) == 0)) 5075 || ((ctxt->rep_prefix == REPNE_PREFIX) && 5076 ((ctxt->eflags & X86_EFLAGS_ZF) == X86_EFLAGS_ZF)))) 5077 return true; 5078 5079 return false; 5080 } 5081 5082 static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt) 5083 { 5084 bool fault = false; 5085 5086 ctxt->ops->get_fpu(ctxt); 5087 asm volatile("1: fwait \n\t" 5088 "2: \n\t" 5089 ".pushsection .fixup,\"ax\" \n\t" 5090 "3: \n\t" 5091 "movb $1, %[fault] \n\t" 5092 "jmp 2b \n\t" 5093 ".popsection \n\t" 5094 _ASM_EXTABLE(1b, 3b) 5095 : [fault]"+qm"(fault)); 5096 ctxt->ops->put_fpu(ctxt); 5097 5098 if (unlikely(fault)) 5099 return emulate_exception(ctxt, MF_VECTOR, 0, false); 5100 5101 return X86EMUL_CONTINUE; 5102 } 5103 5104 static void fetch_possible_mmx_operand(struct x86_emulate_ctxt *ctxt, 5105 struct operand *op) 5106 { 5107 if (op->type == OP_MM) 5108 read_mmx_reg(ctxt, &op->mm_val, op->addr.mm); 5109 } 5110 5111 static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)) 5112 { 5113 register void *__sp asm(_ASM_SP); 5114 ulong flags = (ctxt->eflags & EFLAGS_MASK) | X86_EFLAGS_IF; 5115 5116 if (!(ctxt->d & ByteOp)) 5117 fop += __ffs(ctxt->dst.bytes) * FASTOP_SIZE; 5118 5119 asm("push %[flags]; popf; call *%[fastop]; pushf; pop %[flags]\n" 5120 : "+a"(ctxt->dst.val), "+d"(ctxt->src.val), [flags]"+D"(flags), 5121 [fastop]"+S"(fop), "+r"(__sp) 5122 : "c"(ctxt->src2.val)); 5123 5124 ctxt->eflags = (ctxt->eflags & ~EFLAGS_MASK) | (flags & EFLAGS_MASK); 5125 if (!fop) /* exception is returned in fop variable */ 5126 return emulate_de(ctxt); 5127 return X86EMUL_CONTINUE; 5128 } 5129 5130 void init_decode_cache(struct x86_emulate_ctxt *ctxt) 5131 { 5132 memset(&ctxt->rip_relative, 0, 5133 (void *)&ctxt->modrm - (void *)&ctxt->rip_relative); 5134 5135 ctxt->io_read.pos = 0; 5136 ctxt->io_read.end = 0; 5137 ctxt->mem_read.end = 0; 5138 } 5139 5140 int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) 5141 { 5142 const struct x86_emulate_ops *ops = ctxt->ops; 5143 int rc = X86EMUL_CONTINUE; 5144 int saved_dst_type = ctxt->dst.type; 5145 5146 ctxt->mem_read.pos = 0; 5147 5148 /* LOCK prefix is allowed only with some instructions */ 5149 if (ctxt->lock_prefix && (!(ctxt->d & Lock) || ctxt->dst.type != OP_MEM)) { 5150 rc = emulate_ud(ctxt); 5151 goto done; 5152 } 5153 5154 if ((ctxt->d & SrcMask) == SrcMemFAddr && ctxt->src.type != OP_MEM) { 5155 rc = emulate_ud(ctxt); 5156 goto done; 5157 } 5158 5159 if (unlikely(ctxt->d & 5160 (No64|Undefined|Sse|Mmx|Intercept|CheckPerm|Priv|Prot|String))) { 5161 if ((ctxt->mode == X86EMUL_MODE_PROT64 && (ctxt->d & No64)) || 5162 (ctxt->d & Undefined)) { 5163 rc = emulate_ud(ctxt); 5164 goto done; 5165 } 5166 5167 if (((ctxt->d & (Sse|Mmx)) && ((ops->get_cr(ctxt, 0) & X86_CR0_EM))) 5168 || ((ctxt->d & Sse) && !(ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR))) { 5169 rc = emulate_ud(ctxt); 5170 goto done; 5171 } 5172 5173 if ((ctxt->d & (Sse|Mmx)) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) { 5174 rc = emulate_nm(ctxt); 5175 goto done; 5176 } 5177 5178 if (ctxt->d & Mmx) { 5179 rc = flush_pending_x87_faults(ctxt); 5180 if (rc != X86EMUL_CONTINUE) 5181 goto done; 5182 /* 5183 * Now that we know the fpu is exception safe, we can fetch 5184 * operands from it. 5185 */ 5186 fetch_possible_mmx_operand(ctxt, &ctxt->src); 5187 fetch_possible_mmx_operand(ctxt, &ctxt->src2); 5188 if (!(ctxt->d & Mov)) 5189 fetch_possible_mmx_operand(ctxt, &ctxt->dst); 5190 } 5191 5192 if (unlikely(ctxt->emul_flags & X86EMUL_GUEST_MASK) && ctxt->intercept) { 5193 rc = emulator_check_intercept(ctxt, ctxt->intercept, 5194 X86_ICPT_PRE_EXCEPT); 5195 if (rc != X86EMUL_CONTINUE) 5196 goto done; 5197 } 5198 5199 /* Instruction can only be executed in protected mode */ 5200 if ((ctxt->d & Prot) && ctxt->mode < X86EMUL_MODE_PROT16) { 5201 rc = emulate_ud(ctxt); 5202 goto done; 5203 } 5204 5205 /* Privileged instruction can be executed only in CPL=0 */ 5206 if ((ctxt->d & Priv) && ops->cpl(ctxt)) { 5207 if (ctxt->d & PrivUD) 5208 rc = emulate_ud(ctxt); 5209 else 5210 rc = emulate_gp(ctxt, 0); 5211 goto done; 5212 } 5213 5214 /* Do instruction specific permission checks */ 5215 if (ctxt->d & CheckPerm) { 5216 rc = ctxt->check_perm(ctxt); 5217 if (rc != X86EMUL_CONTINUE) 5218 goto done; 5219 } 5220 5221 if (unlikely(ctxt->emul_flags & X86EMUL_GUEST_MASK) && (ctxt->d & Intercept)) { 5222 rc = emulator_check_intercept(ctxt, ctxt->intercept, 5223 X86_ICPT_POST_EXCEPT); 5224 if (rc != X86EMUL_CONTINUE) 5225 goto done; 5226 } 5227 5228 if (ctxt->rep_prefix && (ctxt->d & String)) { 5229 /* All REP prefixes have the same first termination condition */ 5230 if (address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) == 0) { 5231 string_registers_quirk(ctxt); 5232 ctxt->eip = ctxt->_eip; 5233 ctxt->eflags &= ~X86_EFLAGS_RF; 5234 goto done; 5235 } 5236 } 5237 } 5238 5239 if ((ctxt->src.type == OP_MEM) && !(ctxt->d & NoAccess)) { 5240 rc = segmented_read(ctxt, ctxt->src.addr.mem, 5241 ctxt->src.valptr, ctxt->src.bytes); 5242 if (rc != X86EMUL_CONTINUE) 5243 goto done; 5244 ctxt->src.orig_val64 = ctxt->src.val64; 5245 } 5246 5247 if (ctxt->src2.type == OP_MEM) { 5248 rc = segmented_read(ctxt, ctxt->src2.addr.mem, 5249 &ctxt->src2.val, ctxt->src2.bytes); 5250 if (rc != X86EMUL_CONTINUE) 5251 goto done; 5252 } 5253 5254 if ((ctxt->d & DstMask) == ImplicitOps) 5255 goto special_insn; 5256 5257 5258 if ((ctxt->dst.type == OP_MEM) && !(ctxt->d & Mov)) { 5259 /* optimisation - avoid slow emulated read if Mov */ 5260 rc = segmented_read(ctxt, ctxt->dst.addr.mem, 5261 &ctxt->dst.val, ctxt->dst.bytes); 5262 if (rc != X86EMUL_CONTINUE) { 5263 if (!(ctxt->d & NoWrite) && 5264 rc == X86EMUL_PROPAGATE_FAULT && 5265 ctxt->exception.vector == PF_VECTOR) 5266 ctxt->exception.error_code |= PFERR_WRITE_MASK; 5267 goto done; 5268 } 5269 } 5270 /* Copy full 64-bit value for CMPXCHG8B. */ 5271 ctxt->dst.orig_val64 = ctxt->dst.val64; 5272 5273 special_insn: 5274 5275 if (unlikely(ctxt->emul_flags & X86EMUL_GUEST_MASK) && (ctxt->d & Intercept)) { 5276 rc = emulator_check_intercept(ctxt, ctxt->intercept, 5277 X86_ICPT_POST_MEMACCESS); 5278 if (rc != X86EMUL_CONTINUE) 5279 goto done; 5280 } 5281 5282 if (ctxt->rep_prefix && (ctxt->d & String)) 5283 ctxt->eflags |= X86_EFLAGS_RF; 5284 else 5285 ctxt->eflags &= ~X86_EFLAGS_RF; 5286 5287 if (ctxt->execute) { 5288 if (ctxt->d & Fastop) { 5289 void (*fop)(struct fastop *) = (void *)ctxt->execute; 5290 rc = fastop(ctxt, fop); 5291 if (rc != X86EMUL_CONTINUE) 5292 goto done; 5293 goto writeback; 5294 } 5295 rc = ctxt->execute(ctxt); 5296 if (rc != X86EMUL_CONTINUE) 5297 goto done; 5298 goto writeback; 5299 } 5300 5301 if (ctxt->opcode_len == 2) 5302 goto twobyte_insn; 5303 else if (ctxt->opcode_len == 3) 5304 goto threebyte_insn; 5305 5306 switch (ctxt->b) { 5307 case 0x70 ... 0x7f: /* jcc (short) */ 5308 if (test_cc(ctxt->b, ctxt->eflags)) 5309 rc = jmp_rel(ctxt, ctxt->src.val); 5310 break; 5311 case 0x8d: /* lea r16/r32, m */ 5312 ctxt->dst.val = ctxt->src.addr.mem.ea; 5313 break; 5314 case 0x90 ... 0x97: /* nop / xchg reg, rax */ 5315 if (ctxt->dst.addr.reg == reg_rmw(ctxt, VCPU_REGS_RAX)) 5316 ctxt->dst.type = OP_NONE; 5317 else 5318 rc = em_xchg(ctxt); 5319 break; 5320 case 0x98: /* cbw/cwde/cdqe */ 5321 switch (ctxt->op_bytes) { 5322 case 2: ctxt->dst.val = (s8)ctxt->dst.val; break; 5323 case 4: ctxt->dst.val = (s16)ctxt->dst.val; break; 5324 case 8: ctxt->dst.val = (s32)ctxt->dst.val; break; 5325 } 5326 break; 5327 case 0xcc: /* int3 */ 5328 rc = emulate_int(ctxt, 3); 5329 break; 5330 case 0xcd: /* int n */ 5331 rc = emulate_int(ctxt, ctxt->src.val); 5332 break; 5333 case 0xce: /* into */ 5334 if (ctxt->eflags & X86_EFLAGS_OF) 5335 rc = emulate_int(ctxt, 4); 5336 break; 5337 case 0xe9: /* jmp rel */ 5338 case 0xeb: /* jmp rel short */ 5339 rc = jmp_rel(ctxt, ctxt->src.val); 5340 ctxt->dst.type = OP_NONE; /* Disable writeback. */ 5341 break; 5342 case 0xf4: /* hlt */ 5343 ctxt->ops->halt(ctxt); 5344 break; 5345 case 0xf5: /* cmc */ 5346 /* complement carry flag from eflags reg */ 5347 ctxt->eflags ^= X86_EFLAGS_CF; 5348 break; 5349 case 0xf8: /* clc */ 5350 ctxt->eflags &= ~X86_EFLAGS_CF; 5351 break; 5352 case 0xf9: /* stc */ 5353 ctxt->eflags |= X86_EFLAGS_CF; 5354 break; 5355 case 0xfc: /* cld */ 5356 ctxt->eflags &= ~X86_EFLAGS_DF; 5357 break; 5358 case 0xfd: /* std */ 5359 ctxt->eflags |= X86_EFLAGS_DF; 5360 break; 5361 default: 5362 goto cannot_emulate; 5363 } 5364 5365 if (rc != X86EMUL_CONTINUE) 5366 goto done; 5367 5368 writeback: 5369 if (ctxt->d & SrcWrite) { 5370 BUG_ON(ctxt->src.type == OP_MEM || ctxt->src.type == OP_MEM_STR); 5371 rc = writeback(ctxt, &ctxt->src); 5372 if (rc != X86EMUL_CONTINUE) 5373 goto done; 5374 } 5375 if (!(ctxt->d & NoWrite)) { 5376 rc = writeback(ctxt, &ctxt->dst); 5377 if (rc != X86EMUL_CONTINUE) 5378 goto done; 5379 } 5380 5381 /* 5382 * restore dst type in case the decoding will be reused 5383 * (happens for string instruction ) 5384 */ 5385 ctxt->dst.type = saved_dst_type; 5386 5387 if ((ctxt->d & SrcMask) == SrcSI) 5388 string_addr_inc(ctxt, VCPU_REGS_RSI, &ctxt->src); 5389 5390 if ((ctxt->d & DstMask) == DstDI) 5391 string_addr_inc(ctxt, VCPU_REGS_RDI, &ctxt->dst); 5392 5393 if (ctxt->rep_prefix && (ctxt->d & String)) { 5394 unsigned int count; 5395 struct read_cache *r = &ctxt->io_read; 5396 if ((ctxt->d & SrcMask) == SrcSI) 5397 count = ctxt->src.count; 5398 else 5399 count = ctxt->dst.count; 5400 register_address_increment(ctxt, VCPU_REGS_RCX, -count); 5401 5402 if (!string_insn_completed(ctxt)) { 5403 /* 5404 * Re-enter guest when pio read ahead buffer is empty 5405 * or, if it is not used, after each 1024 iteration. 5406 */ 5407 if ((r->end != 0 || reg_read(ctxt, VCPU_REGS_RCX) & 0x3ff) && 5408 (r->end == 0 || r->end != r->pos)) { 5409 /* 5410 * Reset read cache. Usually happens before 5411 * decode, but since instruction is restarted 5412 * we have to do it here. 5413 */ 5414 ctxt->mem_read.end = 0; 5415 writeback_registers(ctxt); 5416 return EMULATION_RESTART; 5417 } 5418 goto done; /* skip rip writeback */ 5419 } 5420 ctxt->eflags &= ~X86_EFLAGS_RF; 5421 } 5422 5423 ctxt->eip = ctxt->_eip; 5424 5425 done: 5426 if (rc == X86EMUL_PROPAGATE_FAULT) { 5427 WARN_ON(ctxt->exception.vector > 0x1f); 5428 ctxt->have_exception = true; 5429 } 5430 if (rc == X86EMUL_INTERCEPTED) 5431 return EMULATION_INTERCEPTED; 5432 5433 if (rc == X86EMUL_CONTINUE) 5434 writeback_registers(ctxt); 5435 5436 return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK; 5437 5438 twobyte_insn: 5439 switch (ctxt->b) { 5440 case 0x09: /* wbinvd */ 5441 (ctxt->ops->wbinvd)(ctxt); 5442 break; 5443 case 0x08: /* invd */ 5444 case 0x0d: /* GrpP (prefetch) */ 5445 case 0x18: /* Grp16 (prefetch/nop) */ 5446 case 0x1f: /* nop */ 5447 break; 5448 case 0x20: /* mov cr, reg */ 5449 ctxt->dst.val = ops->get_cr(ctxt, ctxt->modrm_reg); 5450 break; 5451 case 0x21: /* mov from dr to reg */ 5452 ops->get_dr(ctxt, ctxt->modrm_reg, &ctxt->dst.val); 5453 break; 5454 case 0x40 ... 0x4f: /* cmov */ 5455 if (test_cc(ctxt->b, ctxt->eflags)) 5456 ctxt->dst.val = ctxt->src.val; 5457 else if (ctxt->op_bytes != 4) 5458 ctxt->dst.type = OP_NONE; /* no writeback */ 5459 break; 5460 case 0x80 ... 0x8f: /* jnz rel, etc*/ 5461 if (test_cc(ctxt->b, ctxt->eflags)) 5462 rc = jmp_rel(ctxt, ctxt->src.val); 5463 break; 5464 case 0x90 ... 0x9f: /* setcc r/m8 */ 5465 ctxt->dst.val = test_cc(ctxt->b, ctxt->eflags); 5466 break; 5467 case 0xb6 ... 0xb7: /* movzx */ 5468 ctxt->dst.bytes = ctxt->op_bytes; 5469 ctxt->dst.val = (ctxt->src.bytes == 1) ? (u8) ctxt->src.val 5470 : (u16) ctxt->src.val; 5471 break; 5472 case 0xbe ... 0xbf: /* movsx */ 5473 ctxt->dst.bytes = ctxt->op_bytes; 5474 ctxt->dst.val = (ctxt->src.bytes == 1) ? (s8) ctxt->src.val : 5475 (s16) ctxt->src.val; 5476 break; 5477 default: 5478 goto cannot_emulate; 5479 } 5480 5481 threebyte_insn: 5482 5483 if (rc != X86EMUL_CONTINUE) 5484 goto done; 5485 5486 goto writeback; 5487 5488 cannot_emulate: 5489 return EMULATION_FAILED; 5490 } 5491 5492 void emulator_invalidate_register_cache(struct x86_emulate_ctxt *ctxt) 5493 { 5494 invalidate_registers(ctxt); 5495 } 5496 5497 void emulator_writeback_register_cache(struct x86_emulate_ctxt *ctxt) 5498 { 5499 writeback_registers(ctxt); 5500 } 5501