]> git.proxmox.com Git - mirror_ubuntu-disco-kernel.git/blob - arch/x86/kvm/emulate.c
projects / mirror_ubuntu-disco-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
block: Cleanup license notice
[mirror_ubuntu-disco-kernel.git] / arch / x86 / kvm / emulate.c
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 <asm/kvm_emulate.h>
26 #include <linux/stringify.h>
27 #include <asm/debugreg.h>
28 #include <asm/nospec-branch.h>
29
30 #include "x86.h"
31 #include "tss.h"
32 #include "mmu.h"
33 #include "pmu.h"
34
35 /*
36 * Operand types
37 */
38 #define OpNone 0ull
39 #define OpImplicit 1ull /* No generic decode */
40 #define OpReg 2ull /* Register */
41 #define OpMem 3ull /* Memory */
42 #define OpAcc 4ull /* Accumulator: AL/AX/EAX/RAX */
43 #define OpDI 5ull /* ES:DI/EDI/RDI */
44 #define OpMem64 6ull /* Memory, 64-bit */
45 #define OpImmUByte 7ull /* Zero-extended 8-bit immediate */
46 #define OpDX 8ull /* DX register */
47 #define OpCL 9ull /* CL register (for shifts) */
48 #define OpImmByte 10ull /* 8-bit sign extended immediate */
49 #define OpOne 11ull /* Implied 1 */
50 #define OpImm 12ull /* Sign extended up to 32-bit immediate */
51 #define OpMem16 13ull /* Memory operand (16-bit). */
52 #define OpMem32 14ull /* Memory operand (32-bit). */
53 #define OpImmU 15ull /* Immediate operand, zero extended */
54 #define OpSI 16ull /* SI/ESI/RSI */
55 #define OpImmFAddr 17ull /* Immediate far address */
56 #define OpMemFAddr 18ull /* Far address in memory */
57 #define OpImmU16 19ull /* Immediate operand, 16 bits, zero extended */
58 #define OpES 20ull /* ES */
59 #define OpCS 21ull /* CS */
60 #define OpSS 22ull /* SS */
61 #define OpDS 23ull /* DS */
62 #define OpFS 24ull /* FS */
63 #define OpGS 25ull /* GS */
64 #define OpMem8 26ull /* 8-bit zero extended memory operand */
65 #define OpImm64 27ull /* Sign extended 16/32/64-bit immediate */
66 #define OpXLat 28ull /* memory at BX/EBX/RBX + zero-extended AL */
67 #define OpAccLo 29ull /* Low part of extended acc (AX/AX/EAX/RAX) */
68 #define OpAccHi 30ull /* High part of extended acc (-/DX/EDX/RDX) */
69
70 #define OpBits 5 /* Width of operand field */
71 #define OpMask ((1ull << OpBits) - 1)
72
73 /*
74 * Opcode effective-address decode tables.
75 * Note that we only emulate instructions that have at least one memory
76 * operand (excluding implicit stack references). We assume that stack
77 * references and instruction fetches will never occur in special memory
78 * areas that require emulation. So, for example, 'mov <imm>,<reg>' need
79 * not be handled.
80 */
81
82 /* Operand sizes: 8-bit operands or specified/overridden size. */
83 #define ByteOp (1<<0) /* 8-bit operands. */
84 /* Destination operand type. */
85 #define DstShift 1
86 #define ImplicitOps (OpImplicit << DstShift)
87 #define DstReg (OpReg << DstShift)
88 #define DstMem (OpMem << DstShift)
89 #define DstAcc (OpAcc << DstShift)
90 #define DstDI (OpDI << DstShift)
91 #define DstMem64 (OpMem64 << DstShift)
92 #define DstMem16 (OpMem16 << DstShift)
93 #define DstImmUByte (OpImmUByte << DstShift)
94 #define DstDX (OpDX << DstShift)
95 #define DstAccLo (OpAccLo << DstShift)
96 #define DstMask (OpMask << DstShift)
97 /* Source operand type. */
98 #define SrcShift 6
99 #define SrcNone (OpNone << SrcShift)
100 #define SrcReg (OpReg << SrcShift)
101 #define SrcMem (OpMem << SrcShift)
102 #define SrcMem16 (OpMem16 << SrcShift)
103 #define SrcMem32 (OpMem32 << SrcShift)
104 #define SrcImm (OpImm << SrcShift)
105 #define SrcImmByte (OpImmByte << SrcShift)
106 #define SrcOne (OpOne << SrcShift)
107 #define SrcImmUByte (OpImmUByte << SrcShift)
108 #define SrcImmU (OpImmU << SrcShift)
109 #define SrcSI (OpSI << SrcShift)
110 #define SrcXLat (OpXLat << SrcShift)
111 #define SrcImmFAddr (OpImmFAddr << SrcShift)
112 #define SrcMemFAddr (OpMemFAddr << SrcShift)
113 #define SrcAcc (OpAcc << SrcShift)
114 #define SrcImmU16 (OpImmU16 << SrcShift)
115 #define SrcImm64 (OpImm64 << SrcShift)
116 #define SrcDX (OpDX << SrcShift)
117 #define SrcMem8 (OpMem8 << SrcShift)
118 #define SrcAccHi (OpAccHi << SrcShift)
119 #define SrcMask (OpMask << SrcShift)
120 #define BitOp (1<<11)
121 #define MemAbs (1<<12) /* Memory operand is absolute displacement */
122 #define String (1<<13) /* String instruction (rep capable) */
123 #define Stack (1<<14) /* Stack instruction (push/pop) */
124 #define GroupMask (7<<15) /* Opcode uses one of the group mechanisms */
125 #define Group (1<<15) /* Bits 3:5 of modrm byte extend opcode */
126 #define GroupDual (2<<15) /* Alternate decoding of mod == 3 */
127 #define Prefix (3<<15) /* Instruction varies with 66/f2/f3 prefix */
128 #define RMExt (4<<15) /* Opcode extension in ModRM r/m if mod == 3 */
129 #define Escape (5<<15) /* Escape to coprocessor instruction */
130 #define InstrDual (6<<15) /* Alternate instruction decoding of mod == 3 */
131 #define ModeDual (7<<15) /* Different instruction for 32/64 bit */
132 #define Sse (1<<18) /* SSE Vector instruction */
133 /* Generic ModRM decode. */
134 #define ModRM (1<<19)
135 /* Destination is only written; never read. */
136 #define Mov (1<<20)
137 /* Misc flags */
138 #define Prot (1<<21) /* instruction generates #UD if not in prot-mode */
139 #define EmulateOnUD (1<<22) /* Emulate if unsupported by the host */
140 #define NoAccess (1<<23) /* Don't access memory (lea/invlpg/verr etc) */
141 #define Op3264 (1<<24) /* Operand is 64b in long mode, 32b otherwise */
142 #define Undefined (1<<25) /* No Such Instruction */
143 #define Lock (1<<26) /* lock prefix is allowed for the instruction */
144 #define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */
145 #define No64 (1<<28)
146 #define PageTable (1 << 29) /* instruction used to write page table */
147 #define NotImpl (1 << 30) /* instruction is not implemented */
148 /* Source 2 operand type */
149 #define Src2Shift (31)
150 #define Src2None (OpNone << Src2Shift)
151 #define Src2Mem (OpMem << Src2Shift)
152 #define Src2CL (OpCL << Src2Shift)
153 #define Src2ImmByte (OpImmByte << Src2Shift)
154 #define Src2One (OpOne << Src2Shift)
155 #define Src2Imm (OpImm << Src2Shift)
156 #define Src2ES (OpES << Src2Shift)
157 #define Src2CS (OpCS << Src2Shift)
158 #define Src2SS (OpSS << Src2Shift)
159 #define Src2DS (OpDS << Src2Shift)
160 #define Src2FS (OpFS << Src2Shift)
161 #define Src2GS (OpGS << Src2Shift)
162 #define Src2Mask (OpMask << Src2Shift)
163 #define Mmx ((u64)1 << 40) /* MMX Vector instruction */
164 #define AlignMask ((u64)7 << 41)
165 #define Aligned ((u64)1 << 41) /* Explicitly aligned (e.g. MOVDQA) */
166 #define Unaligned ((u64)2 << 41) /* Explicitly unaligned (e.g. MOVDQU) */
167 #define Avx ((u64)3 << 41) /* Advanced Vector Extensions */
168 #define Aligned16 ((u64)4 << 41) /* Aligned to 16 byte boundary (e.g. FXSAVE) */
169 #define Fastop ((u64)1 << 44) /* Use opcode::u.fastop */
170 #define NoWrite ((u64)1 << 45) /* No writeback */
171 #define SrcWrite ((u64)1 << 46) /* Write back src operand */
172 #define NoMod ((u64)1 << 47) /* Mod field is ignored */
173 #define Intercept ((u64)1 << 48) /* Has valid intercept field */
174 #define CheckPerm ((u64)1 << 49) /* Has valid check_perm field */
175 #define PrivUD ((u64)1 << 51) /* #UD instead of #GP on CPL > 0 */
176 #define NearBranch ((u64)1 << 52) /* Near branches */
177 #define No16 ((u64)1 << 53) /* No 16 bit operand */
178 #define IncSP ((u64)1 << 54) /* SP is incremented before ModRM calc */
179 #define TwoMemOp ((u64)1 << 55) /* Instruction has two memory operand */
180
181 #define DstXacc (DstAccLo | SrcAccHi | SrcWrite)
182
183 #define X2(x...) x, x
184 #define X3(x...) X2(x), x
185 #define X4(x...) X2(x), X2(x)
186 #define X5(x...) X4(x), x
187 #define X6(x...) X4(x), X2(x)
188 #define X7(x...) X4(x), X3(x)
189 #define X8(x...) X4(x), X4(x)
190 #define X16(x...) X8(x), X8(x)
191
192 #define NR_FASTOP (ilog2(sizeof(ulong)) + 1)
193 #define FASTOP_SIZE 8
194
195 /*
196 * fastop functions have a special calling convention:
197 *
198 * dst: rax (in/out)
199 * src: rdx (in/out)
200 * src2: rcx (in)
201 * flags: rflags (in/out)
202 * ex: rsi (in:fastop pointer, out:zero if exception)
203 *
204 * Moreover, they are all exactly FASTOP_SIZE bytes long, so functions for
205 * different operand sizes can be reached by calculation, rather than a jump
206 * table (which would be bigger than the code).
207 *
208 * fastop functions are declared as taking a never-defined fastop parameter,
209 * so they can't be called from C directly.
210 */
211
212 struct fastop;
213
214 struct opcode {
215 u64 flags : 56;
216 u64 intercept : 8;
217 union {
218 int (*execute)(struct x86_emulate_ctxt *ctxt);
219 const struct opcode *group;
220 const struct group_dual *gdual;
221 const struct gprefix *gprefix;
222 const struct escape *esc;
223 const struct instr_dual *idual;
224 const struct mode_dual *mdual;
225 void (*fastop)(struct fastop *fake);
226 } u;
227 int (*check_perm)(struct x86_emulate_ctxt *ctxt);
228 };
229
230 struct group_dual {
231 struct opcode mod012[8];
232 struct opcode mod3[8];
233 };
234
235 struct gprefix {
236 struct opcode pfx_no;
237 struct opcode pfx_66;
238 struct opcode pfx_f2;
239 struct opcode pfx_f3;
240 };
241
242 struct escape {
243 struct opcode op[8];
244 struct opcode high[64];
245 };
246
247 struct instr_dual {
248 struct opcode mod012;
249 struct opcode mod3;
250 };
251
252 struct mode_dual {
253 struct opcode mode32;
254 struct opcode mode64;
255 };
256
257 #define EFLG_RESERVED_ZEROS_MASK 0xffc0802a
258
259 enum x86_transfer_type {
260 X86_TRANSFER_NONE,
261 X86_TRANSFER_CALL_JMP,
262 X86_TRANSFER_RET,
263 X86_TRANSFER_TASK_SWITCH,
264 };
265
266 static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr)
267 {
268 if (!(ctxt->regs_valid & (1 << nr))) {
269 ctxt->regs_valid |= 1 << nr;
270 ctxt->_regs[nr] = ctxt->ops->read_gpr(ctxt, nr);
271 }
272 return ctxt->_regs[nr];
273 }
274
275 static ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr)
276 {
277 ctxt->regs_valid |= 1 << nr;
278 ctxt->regs_dirty |= 1 << nr;
279 return &ctxt->_regs[nr];
280 }
281
282 static ulong *reg_rmw(struct x86_emulate_ctxt *ctxt, unsigned nr)
283 {
284 reg_read(ctxt, nr);
285 return reg_write(ctxt, nr);
286 }
287
288 static void writeback_registers(struct x86_emulate_ctxt *ctxt)
289 {
290 unsigned reg;
291
292 for_each_set_bit(reg, (ulong *)&ctxt->regs_dirty, 16)
293 ctxt->ops->write_gpr(ctxt, reg, ctxt->_regs[reg]);
294 }
295
296 static void invalidate_registers(struct x86_emulate_ctxt *ctxt)
297 {
298 ctxt->regs_dirty = 0;
299 ctxt->regs_valid = 0;
300 }
301
302 /*
303 * These EFLAGS bits are restored from saved value during emulation, and
304 * any changes are written back to the saved value after emulation.
305 */
306 #define EFLAGS_MASK (X86_EFLAGS_OF|X86_EFLAGS_SF|X86_EFLAGS_ZF|X86_EFLAGS_AF|\
307 X86_EFLAGS_PF|X86_EFLAGS_CF)
308
309 #ifdef CONFIG_X86_64
310 #define ON64(x) x
311 #else
312 #define ON64(x)
313 #endif
314
315 static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *));
316
317 #define FOP_FUNC(name) \
318 ".align " __stringify(FASTOP_SIZE) " \n\t" \
319 ".type " name ", @function \n\t" \
320 name ":\n\t"
321
322 #define FOP_RET "ret \n\t"
323
324 #define FOP_START(op) \
325 extern void em_##op(struct fastop *fake); \
326 asm(".pushsection .text, \"ax\" \n\t" \
327 ".global em_" #op " \n\t" \
328 FOP_FUNC("em_" #op)
329
330 #define FOP_END \
331 ".popsection")
332
333 #define FOPNOP() \
334 FOP_FUNC(__stringify(__UNIQUE_ID(nop))) \
335 FOP_RET
336
337 #define FOP1E(op, dst) \
338 FOP_FUNC(#op "_" #dst) \
339 "10: " #op " %" #dst " \n\t" FOP_RET
340
341 #define FOP1EEX(op, dst) \
342 FOP1E(op, dst) _ASM_EXTABLE(10b, kvm_fastop_exception)
343
344 #define FASTOP1(op) \
345 FOP_START(op) \
346 FOP1E(op##b, al) \
347 FOP1E(op##w, ax) \
348 FOP1E(op##l, eax) \
349 ON64(FOP1E(op##q, rax)) \
350 FOP_END
351
352 /* 1-operand, using src2 (for MUL/DIV r/m) */
353 #define FASTOP1SRC2(op, name) \
354 FOP_START(name) \
355 FOP1E(op, cl) \
356 FOP1E(op, cx) \
357 FOP1E(op, ecx) \
358 ON64(FOP1E(op, rcx)) \
359 FOP_END
360
361 /* 1-operand, using src2 (for MUL/DIV r/m), with exceptions */
362 #define FASTOP1SRC2EX(op, name) \
363 FOP_START(name) \
364 FOP1EEX(op, cl) \
365 FOP1EEX(op, cx) \
366 FOP1EEX(op, ecx) \
367 ON64(FOP1EEX(op, rcx)) \
368 FOP_END
369
370 #define FOP2E(op, dst, src) \
371 FOP_FUNC(#op "_" #dst "_" #src) \
372 #op " %" #src ", %" #dst " \n\t" FOP_RET
373
374 #define FASTOP2(op) \
375 FOP_START(op) \
376 FOP2E(op##b, al, dl) \
377 FOP2E(op##w, ax, dx) \
378 FOP2E(op##l, eax, edx) \
379 ON64(FOP2E(op##q, rax, rdx)) \
380 FOP_END
381
382 /* 2 operand, word only */
383 #define FASTOP2W(op) \
384 FOP_START(op) \
385 FOPNOP() \
386 FOP2E(op##w, ax, dx) \
387 FOP2E(op##l, eax, edx) \
388 ON64(FOP2E(op##q, rax, rdx)) \
389 FOP_END
390
391 /* 2 operand, src is CL */
392 #define FASTOP2CL(op) \
393 FOP_START(op) \
394 FOP2E(op##b, al, cl) \
395 FOP2E(op##w, ax, cl) \
396 FOP2E(op##l, eax, cl) \
397 ON64(FOP2E(op##q, rax, cl)) \
398 FOP_END
399
400 /* 2 operand, src and dest are reversed */
401 #define FASTOP2R(op, name) \
402 FOP_START(name) \
403 FOP2E(op##b, dl, al) \
404 FOP2E(op##w, dx, ax) \
405 FOP2E(op##l, edx, eax) \
406 ON64(FOP2E(op##q, rdx, rax)) \
407 FOP_END
408
409 #define FOP3E(op, dst, src, src2) \
410 FOP_FUNC(#op "_" #dst "_" #src "_" #src2) \
411 #op " %" #src2 ", %" #src ", %" #dst " \n\t" FOP_RET
412
413 /* 3-operand, word-only, src2=cl */
414 #define FASTOP3WCL(op) \
415 FOP_START(op) \
416 FOPNOP() \
417 FOP3E(op##w, ax, dx, cl) \
418 FOP3E(op##l, eax, edx, cl) \
419 ON64(FOP3E(op##q, rax, rdx, cl)) \
420 FOP_END
421
422 /* Special case for SETcc - 1 instruction per cc */
423 #define FOP_SETCC(op) \
424 ".align 4 \n\t" \
425 ".type " #op ", @function \n\t" \
426 #op ": \n\t" \
427 #op " %al \n\t" \
428 FOP_RET
429
430 asm(".pushsection .fixup, \"ax\"\n"
431 ".global kvm_fastop_exception \n"
432 "kvm_fastop_exception: xor %esi, %esi; ret\n"
433 ".popsection");
434
435 FOP_START(setcc)
436 FOP_SETCC(seto)
437 FOP_SETCC(setno)
438 FOP_SETCC(setc)
439 FOP_SETCC(setnc)
440 FOP_SETCC(setz)
441 FOP_SETCC(setnz)
442 FOP_SETCC(setbe)
443 FOP_SETCC(setnbe)
444 FOP_SETCC(sets)
445 FOP_SETCC(setns)
446 FOP_SETCC(setp)
447 FOP_SETCC(setnp)
448 FOP_SETCC(setl)
449 FOP_SETCC(setnl)
450 FOP_SETCC(setle)
451 FOP_SETCC(setnle)
452 FOP_END;
453
454 FOP_START(salc) "pushf; sbb %al, %al; popf \n\t" FOP_RET
455 FOP_END;
456
457 /*
458 * XXX: inoutclob user must know where the argument is being expanded.
459 * Relying on CC_HAVE_ASM_GOTO would allow us to remove _fault.
460 */
461 #define asm_safe(insn, inoutclob...) \
462 ({ \
463 int _fault = 0; \
464 \
465 asm volatile("1:" insn "\n" \
466 "2:\n" \
467 ".pushsection .fixup, \"ax\"\n" \
468 "3: movl $1, %[_fault]\n" \
469 " jmp 2b\n" \
470 ".popsection\n" \
471 _ASM_EXTABLE(1b, 3b) \
472 : [_fault] "+qm"(_fault) inoutclob ); \
473 \
474 _fault ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE; \
475 })
476
477 static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt,
478 enum x86_intercept intercept,
479 enum x86_intercept_stage stage)
480 {
481 struct x86_instruction_info info = {
482 .intercept = intercept,
483 .rep_prefix = ctxt->rep_prefix,
484 .modrm_mod = ctxt->modrm_mod,
485 .modrm_reg = ctxt->modrm_reg,
486 .modrm_rm = ctxt->modrm_rm,
487 .src_val = ctxt->src.val64,
488 .dst_val = ctxt->dst.val64,
489 .src_bytes = ctxt->src.bytes,
490 .dst_bytes = ctxt->dst.bytes,
491 .ad_bytes = ctxt->ad_bytes,
492 .next_rip = ctxt->eip,
493 };
494
495 return ctxt->ops->intercept(ctxt, &info, stage);
496 }
497
498 static void assign_masked(ulong *dest, ulong src, ulong mask)
499 {
500 *dest = (*dest & ~mask) | (src & mask);
501 }
502
503 static void assign_register(unsigned long *reg, u64 val, int bytes)
504 {
505 /* The 4-byte case *is* correct: in 64-bit mode we zero-extend. */
506 switch (bytes) {
507 case 1:
508 *(u8 *)reg = (u8)val;
509 break;
510 case 2:
511 *(u16 *)reg = (u16)val;
512 break;
513 case 4:
514 *reg = (u32)val;
515 break; /* 64b: zero-extend */
516 case 8:
517 *reg = val;
518 break;
519 }
520 }
521
522 static inline unsigned long ad_mask(struct x86_emulate_ctxt *ctxt)
523 {
524 return (1UL << (ctxt->ad_bytes << 3)) - 1;
525 }
526
527 static ulong stack_mask(struct x86_emulate_ctxt *ctxt)
528 {
529 u16 sel;
530 struct desc_struct ss;
531
532 if (ctxt->mode == X86EMUL_MODE_PROT64)
533 return ~0UL;
534 ctxt->ops->get_segment(ctxt, &sel, &ss, NULL, VCPU_SREG_SS);
535 return ~0U >> ((ss.d ^ 1) * 16); /* d=0: 0xffff; d=1: 0xffffffff */
536 }
537
538 static int stack_size(struct x86_emulate_ctxt *ctxt)
539 {
540 return (__fls(stack_mask(ctxt)) + 1) >> 3;
541 }
542
543 /* Access/update address held in a register, based on addressing mode. */
544 static inline unsigned long
545 address_mask(struct x86_emulate_ctxt *ctxt, unsigned long reg)
546 {
547 if (ctxt->ad_bytes == sizeof(unsigned long))
548 return reg;
549 else
550 return reg & ad_mask(ctxt);
551 }
552
553 static inline unsigned long
554 register_address(struct x86_emulate_ctxt *ctxt, int reg)
555 {
556 return address_mask(ctxt, reg_read(ctxt, reg));
557 }
558
559 static void masked_increment(ulong *reg, ulong mask, int inc)
560 {
561 assign_masked(reg, *reg + inc, mask);
562 }
563
564 static inline void
565 register_address_increment(struct x86_emulate_ctxt *ctxt, int reg, int inc)
566 {
567 ulong *preg = reg_rmw(ctxt, reg);
568
569 assign_register(preg, *preg + inc, ctxt->ad_bytes);
570 }
571
572 static void rsp_increment(struct x86_emulate_ctxt *ctxt, int inc)
573 {
574 masked_increment(reg_rmw(ctxt, VCPU_REGS_RSP), stack_mask(ctxt), inc);
575 }
576
577 static u32 desc_limit_scaled(struct desc_struct *desc)
578 {
579 u32 limit = get_desc_limit(desc);
580
581 return desc->g ? (limit << 12) | 0xfff : limit;
582 }
583
584 static unsigned long seg_base(struct x86_emulate_ctxt *ctxt, int seg)
585 {
586 if (ctxt->mode == X86EMUL_MODE_PROT64 && seg < VCPU_SREG_FS)
587 return 0;
588
589 return ctxt->ops->get_cached_segment_base(ctxt, seg);
590 }
591
592 static int emulate_exception(struct x86_emulate_ctxt *ctxt, int vec,
593 u32 error, bool valid)
594 {
595 WARN_ON(vec > 0x1f);
596 ctxt->exception.vector = vec;
597 ctxt->exception.error_code = error;
598 ctxt->exception.error_code_valid = valid;
599 return X86EMUL_PROPAGATE_FAULT;
600 }
601
602 static int emulate_db(struct x86_emulate_ctxt *ctxt)
603 {
604 return emulate_exception(ctxt, DB_VECTOR, 0, false);
605 }
606
607 static int emulate_gp(struct x86_emulate_ctxt *ctxt, int err)
608 {
609 return emulate_exception(ctxt, GP_VECTOR, err, true);
610 }
611
612 static int emulate_ss(struct x86_emulate_ctxt *ctxt, int err)
613 {
614 return emulate_exception(ctxt, SS_VECTOR, err, true);
615 }
616
617 static int emulate_ud(struct x86_emulate_ctxt *ctxt)
618 {
619 return emulate_exception(ctxt, UD_VECTOR, 0, false);
620 }
621
622 static int emulate_ts(struct x86_emulate_ctxt *ctxt, int err)
623 {
624 return emulate_exception(ctxt, TS_VECTOR, err, true);
625 }
626
627 static int emulate_de(struct x86_emulate_ctxt *ctxt)
628 {
629 return emulate_exception(ctxt, DE_VECTOR, 0, false);
630 }
631
632 static int emulate_nm(struct x86_emulate_ctxt *ctxt)
633 {
634 return emulate_exception(ctxt, NM_VECTOR, 0, false);
635 }
636
637 static u16 get_segment_selector(struct x86_emulate_ctxt *ctxt, unsigned seg)
638 {
639 u16 selector;
640 struct desc_struct desc;
641
642 ctxt->ops->get_segment(ctxt, &selector, &desc, NULL, seg);
643 return selector;
644 }
645
646 static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector,
647 unsigned seg)
648 {
649 u16 dummy;
650 u32 base3;
651 struct desc_struct desc;
652
653 ctxt->ops->get_segment(ctxt, &dummy, &desc, &base3, seg);
654 ctxt->ops->set_segment(ctxt, selector, &desc, base3, seg);
655 }
656
657 /*
658 * x86 defines three classes of vector instructions: explicitly
659 * aligned, explicitly unaligned, and the rest, which change behaviour
660 * depending on whether they're AVX encoded or not.
661 *
662 * Also included is CMPXCHG16B which is not a vector instruction, yet it is
663 * subject to the same check. FXSAVE and FXRSTOR are checked here too as their
664 * 512 bytes of data must be aligned to a 16 byte boundary.
665 */
666 static unsigned insn_alignment(struct x86_emulate_ctxt *ctxt, unsigned size)
667 {
668 u64 alignment = ctxt->d & AlignMask;
669
670 if (likely(size < 16))
671 return 1;
672
673 switch (alignment) {
674 case Unaligned:
675 case Avx:
676 return 1;
677 case Aligned16:
678 return 16;
679 case Aligned:
680 default:
681 return size;
682 }
683 }
684
685 static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
686 struct segmented_address addr,
687 unsigned *max_size, unsigned size,
688 bool write, bool fetch,
689 enum x86emul_mode mode, ulong *linear)
690 {
691 struct desc_struct desc;
692 bool usable;
693 ulong la;
694 u32 lim;
695 u16 sel;
696 u8 va_bits;
697
698 la = seg_base(ctxt, addr.seg) + addr.ea;
699 *max_size = 0;
700 switch (mode) {
701 case X86EMUL_MODE_PROT64:
702 *linear = la;
703 va_bits = ctxt_virt_addr_bits(ctxt);
704 if (get_canonical(la, va_bits) != la)
705 goto bad;
706
707 *max_size = min_t(u64, ~0u, (1ull << va_bits) - la);
708 if (size > *max_size)
709 goto bad;
710 break;
711 default:
712 *linear = la = (u32)la;
713 usable = ctxt->ops->get_segment(ctxt, &sel, &desc, NULL,
714 addr.seg);
715 if (!usable)
716 goto bad;
717 /* code segment in protected mode or read-only data segment */
718 if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8))
719 || !(desc.type & 2)) && write)
720 goto bad;
721 /* unreadable code segment */
722 if (!fetch && (desc.type & 8) && !(desc.type & 2))
723 goto bad;
724 lim = desc_limit_scaled(&desc);
725 if (!(desc.type & 8) && (desc.type & 4)) {
726 /* expand-down segment */
727 if (addr.ea <= lim)
728 goto bad;
729 lim = desc.d ? 0xffffffff : 0xffff;
730 }
731 if (addr.ea > lim)
732 goto bad;
733 if (lim == 0xffffffff)
734 *max_size = ~0u;
735 else {
736 *max_size = (u64)lim + 1 - addr.ea;
737 if (size > *max_size)
738 goto bad;
739 }
740 break;
741 }
742 if (la & (insn_alignment(ctxt, size) - 1))
743 return emulate_gp(ctxt, 0);
744 return X86EMUL_CONTINUE;
745 bad:
746 if (addr.seg == VCPU_SREG_SS)
747 return emulate_ss(ctxt, 0);
748 else
749 return emulate_gp(ctxt, 0);
750 }
751
752 static int linearize(struct x86_emulate_ctxt *ctxt,
753 struct segmented_address addr,
754 unsigned size, bool write,
755 ulong *linear)
756 {
757 unsigned max_size;
758 return __linearize(ctxt, addr, &max_size, size, write, false,
759 ctxt->mode, linear);
760 }
761
762 static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
763 enum x86emul_mode mode)
764 {
765 ulong linear;
766 int rc;
767 unsigned max_size;
768 struct segmented_address addr = { .seg = VCPU_SREG_CS,
769 .ea = dst };
770
771 if (ctxt->op_bytes != sizeof(unsigned long))
772 addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
773 rc = __linearize(ctxt, addr, &max_size, 1, false, true, mode, &linear);
774 if (rc == X86EMUL_CONTINUE)
775 ctxt->_eip = addr.ea;
776 return rc;
777 }
778
779 static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst)
780 {
781 return assign_eip(ctxt, dst, ctxt->mode);
782 }
783
784 static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst,
785 const struct desc_struct *cs_desc)
786 {
787 enum x86emul_mode mode = ctxt->mode;
788 int rc;
789
790 #ifdef CONFIG_X86_64
791 if (ctxt->mode >= X86EMUL_MODE_PROT16) {
792 if (cs_desc->l) {
793 u64 efer = 0;
794
795 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
796 if (efer & EFER_LMA)
797 mode = X86EMUL_MODE_PROT64;
798 } else
799 mode = X86EMUL_MODE_PROT32; /* temporary value */
800 }
801 #endif
802 if (mode == X86EMUL_MODE_PROT16 || mode == X86EMUL_MODE_PROT32)
803 mode = cs_desc->d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
804 rc = assign_eip(ctxt, dst, mode);
805 if (rc == X86EMUL_CONTINUE)
806 ctxt->mode = mode;
807 return rc;
808 }
809
810 static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
811 {
812 return assign_eip_near(ctxt, ctxt->_eip + rel);
813 }
814
815 static int linear_read_system(struct x86_emulate_ctxt *ctxt, ulong linear,
816 void *data, unsigned size)
817 {
818 return ctxt->ops->read_std(ctxt, linear, data, size, &ctxt->exception, true);
819 }
820
821 static int linear_write_system(struct x86_emulate_ctxt *ctxt,
822 ulong linear, void *data,
823 unsigned int size)
824 {
825 return ctxt->ops->write_std(ctxt, linear, data, size, &ctxt->exception, true);
826 }
827
828 static int segmented_read_std(struct x86_emulate_ctxt *ctxt,
829 struct segmented_address addr,
830 void *data,
831 unsigned size)
832 {
833 int rc;
834 ulong linear;
835
836 rc = linearize(ctxt, addr, size, false, &linear);
837 if (rc != X86EMUL_CONTINUE)
838 return rc;
839 return ctxt->ops->read_std(ctxt, linear, data, size, &ctxt->exception, false);
840 }
841
842 static int segmented_write_std(struct x86_emulate_ctxt *ctxt,
843 struct segmented_address addr,
844 void *data,
845 unsigned int size)
846 {
847 int rc;
848 ulong linear;
849
850 rc = linearize(ctxt, addr, size, true, &linear);
851 if (rc != X86EMUL_CONTINUE)
852 return rc;
853 return ctxt->ops->write_std(ctxt, linear, data, size, &ctxt->exception, false);
854 }
855
856 /*
857 * Prefetch the remaining bytes of the instruction without crossing page
858 * boundary if they are not in fetch_cache yet.
859 */
860 static int __do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt, int op_size)
861 {
862 int rc;
863 unsigned size, max_size;
864 unsigned long linear;
865 int cur_size = ctxt->fetch.end - ctxt->fetch.data;
866 struct segmented_address addr = { .seg = VCPU_SREG_CS,
867 .ea = ctxt->eip + cur_size };
868
869 /*
870 * We do not know exactly how many bytes will be needed, and
871 * __linearize is expensive, so fetch as much as possible. We
872 * just have to avoid going beyond the 15 byte limit, the end
873 * of the segment, or the end of the page.
874 *
875 * __linearize is called with size 0 so that it does not do any
876 * boundary check itself. Instead, we use max_size to check
877 * against op_size.
878 */
879 rc = __linearize(ctxt, addr, &max_size, 0, false, true, ctxt->mode,
880 &linear);
881 if (unlikely(rc != X86EMUL_CONTINUE))
882 return rc;
883
884 size = min_t(unsigned, 15UL ^ cur_size, max_size);
885 size = min_t(unsigned, size, PAGE_SIZE - offset_in_page(linear));
886
887 /*
888 * One instruction can only straddle two pages,
889 * and one has been loaded at the beginning of
890 * x86_decode_insn. So, if not enough bytes
891 * still, we must have hit the 15-byte boundary.
892 */
893 if (unlikely(size < op_size))
894 return emulate_gp(ctxt, 0);
895
896 rc = ctxt->ops->fetch(ctxt, linear, ctxt->fetch.end,
897 size, &ctxt->exception);
898 if (unlikely(rc != X86EMUL_CONTINUE))
899 return rc;
900 ctxt->fetch.end += size;
901 return X86EMUL_CONTINUE;
902 }
903
904 static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt,
905 unsigned size)
906 {
907 unsigned done_size = ctxt->fetch.end - ctxt->fetch.ptr;
908
909 if (unlikely(done_size < size))
910 return __do_insn_fetch_bytes(ctxt, size - done_size);
911 else
912 return X86EMUL_CONTINUE;
913 }
914
915 /* Fetch next part of the instruction being emulated. */
916 #define insn_fetch(_type, _ctxt) \
917 ({ _type _x; \
918 \
919 rc = do_insn_fetch_bytes(_ctxt, sizeof(_type)); \
920 if (rc != X86EMUL_CONTINUE) \
921 goto done; \
922 ctxt->_eip += sizeof(_type); \
923 memcpy(&_x, ctxt->fetch.ptr, sizeof(_type)); \
924 ctxt->fetch.ptr += sizeof(_type); \
925 _x; \
926 })
927
928 #define insn_fetch_arr(_arr, _size, _ctxt) \
929 ({ \
930 rc = do_insn_fetch_bytes(_ctxt, _size); \
931 if (rc != X86EMUL_CONTINUE) \
932 goto done; \
933 ctxt->_eip += (_size); \
934 memcpy(_arr, ctxt->fetch.ptr, _size); \
935 ctxt->fetch.ptr += (_size); \
936 })
937
938 /*
939 * Given the 'reg' portion of a ModRM byte, and a register block, return a
940 * pointer into the block that addresses the relevant register.
941 * @highbyte_regs specifies whether to decode AH,CH,DH,BH.
942 */
943 static void *decode_register(struct x86_emulate_ctxt *ctxt, u8 modrm_reg,
944 int byteop)
945 {
946 void *p;
947 int highbyte_regs = (ctxt->rex_prefix == 0) && byteop;
948
949 if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8)
950 p = (unsigned char *)reg_rmw(ctxt, modrm_reg & 3) + 1;
951 else
952 p = reg_rmw(ctxt, modrm_reg);
953 return p;
954 }
955
956 static int read_descriptor(struct x86_emulate_ctxt *ctxt,
957 struct segmented_address addr,
958 u16 *size, unsigned long *address, int op_bytes)
959 {
960 int rc;
961
962 if (op_bytes == 2)
963 op_bytes = 3;
964 *address = 0;
965 rc = segmented_read_std(ctxt, addr, size, 2);
966 if (rc != X86EMUL_CONTINUE)
967 return rc;
968 addr.ea += 2;
969 rc = segmented_read_std(ctxt, addr, address, op_bytes);
970 return rc;
971 }
972
973 FASTOP2(add);
974 FASTOP2(or);
975 FASTOP2(adc);
976 FASTOP2(sbb);
977 FASTOP2(and);
978 FASTOP2(sub);
979 FASTOP2(xor);
980 FASTOP2(cmp);
981 FASTOP2(test);
982
983 FASTOP1SRC2(mul, mul_ex);
984 FASTOP1SRC2(imul, imul_ex);
985 FASTOP1SRC2EX(div, div_ex);
986 FASTOP1SRC2EX(idiv, idiv_ex);
987
988 FASTOP3WCL(shld);
989 FASTOP3WCL(shrd);
990
991 FASTOP2W(imul);
992
993 FASTOP1(not);
994 FASTOP1(neg);
995 FASTOP1(inc);
996 FASTOP1(dec);
997
998 FASTOP2CL(rol);
999 FASTOP2CL(ror);
1000 FASTOP2CL(rcl);
1001 FASTOP2CL(rcr);
1002 FASTOP2CL(shl);
1003 FASTOP2CL(shr);
1004 FASTOP2CL(sar);
1005
1006 FASTOP2W(bsf);
1007 FASTOP2W(bsr);
1008 FASTOP2W(bt);
1009 FASTOP2W(bts);
1010 FASTOP2W(btr);
1011 FASTOP2W(btc);
1012
1013 FASTOP2(xadd);
1014
1015 FASTOP2R(cmp, cmp_r);
1016
1017 static int em_bsf_c(struct x86_emulate_ctxt *ctxt)
1018 {
1019 /* If src is zero, do not writeback, but update flags */
1020 if (ctxt->src.val == 0)
1021 ctxt->dst.type = OP_NONE;
1022 return fastop(ctxt, em_bsf);
1023 }
1024
1025 static int em_bsr_c(struct x86_emulate_ctxt *ctxt)
1026 {
1027 /* If src is zero, do not writeback, but update flags */
1028 if (ctxt->src.val == 0)
1029 ctxt->dst.type = OP_NONE;
1030 return fastop(ctxt, em_bsr);
1031 }
1032
1033 static __always_inline u8 test_cc(unsigned int condition, unsigned long flags)
1034 {
1035 u8 rc;
1036 void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf);
1037
1038 flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF;
1039 asm("push %[flags]; popf; " CALL_NOSPEC
1040 : "=a"(rc) : [thunk_target]"r"(fop), [flags]"r"(flags));
1041 return rc;
1042 }
1043
1044 static void fetch_register_operand(struct operand *op)
1045 {
1046 switch (op->bytes) {
1047 case 1:
1048 op->val = *(u8 *)op->addr.reg;
1049 break;
1050 case 2:
1051 op->val = *(u16 *)op->addr.reg;
1052 break;
1053 case 4:
1054 op->val = *(u32 *)op->addr.reg;
1055 break;
1056 case 8:
1057 op->val = *(u64 *)op->addr.reg;
1058 break;
1059 }
1060 }
1061
1062 static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg)
1063 {
1064 switch (reg) {
1065 case 0: asm("movdqa %%xmm0, %0" : "=m"(*data)); break;
1066 case 1: asm("movdqa %%xmm1, %0" : "=m"(*data)); break;
1067 case 2: asm("movdqa %%xmm2, %0" : "=m"(*data)); break;
1068 case 3: asm("movdqa %%xmm3, %0" : "=m"(*data)); break;
1069 case 4: asm("movdqa %%xmm4, %0" : "=m"(*data)); break;
1070 case 5: asm("movdqa %%xmm5, %0" : "=m"(*data)); break;
1071 case 6: asm("movdqa %%xmm6, %0" : "=m"(*data)); break;
1072 case 7: asm("movdqa %%xmm7, %0" : "=m"(*data)); break;
1073 #ifdef CONFIG_X86_64
1074 case 8: asm("movdqa %%xmm8, %0" : "=m"(*data)); break;
1075 case 9: asm("movdqa %%xmm9, %0" : "=m"(*data)); break;
1076 case 10: asm("movdqa %%xmm10, %0" : "=m"(*data)); break;
1077 case 11: asm("movdqa %%xmm11, %0" : "=m"(*data)); break;
1078 case 12: asm("movdqa %%xmm12, %0" : "=m"(*data)); break;
1079 case 13: asm("movdqa %%xmm13, %0" : "=m"(*data)); break;
1080 case 14: asm("movdqa %%xmm14, %0" : "=m"(*data)); break;
1081 case 15: asm("movdqa %%xmm15, %0" : "=m"(*data)); break;
1082 #endif
1083 default: BUG();
1084 }
1085 }
1086
1087 static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
1088 int reg)
1089 {
1090 switch (reg) {
1091 case 0: asm("movdqa %0, %%xmm0" : : "m"(*data)); break;
1092 case 1: asm("movdqa %0, %%xmm1" : : "m"(*data)); break;
1093 case 2: asm("movdqa %0, %%xmm2" : : "m"(*data)); break;
1094 case 3: asm("movdqa %0, %%xmm3" : : "m"(*data)); break;
1095 case 4: asm("movdqa %0, %%xmm4" : : "m"(*data)); break;
1096 case 5: asm("movdqa %0, %%xmm5" : : "m"(*data)); break;
1097 case 6: asm("movdqa %0, %%xmm6" : : "m"(*data)); break;
1098 case 7: asm("movdqa %0, %%xmm7" : : "m"(*data)); break;
1099 #ifdef CONFIG_X86_64
1100 case 8: asm("movdqa %0, %%xmm8" : : "m"(*data)); break;
1101 case 9: asm("movdqa %0, %%xmm9" : : "m"(*data)); break;
1102 case 10: asm("movdqa %0, %%xmm10" : : "m"(*data)); break;
1103 case 11: asm("movdqa %0, %%xmm11" : : "m"(*data)); break;
1104 case 12: asm("movdqa %0, %%xmm12" : : "m"(*data)); break;
1105 case 13: asm("movdqa %0, %%xmm13" : : "m"(*data)); break;
1106 case 14: asm("movdqa %0, %%xmm14" : : "m"(*data)); break;
1107 case 15: asm("movdqa %0, %%xmm15" : : "m"(*data)); break;
1108 #endif
1109 default: BUG();
1110 }
1111 }
1112
1113 static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
1114 {
1115 switch (reg) {
1116 case 0: asm("movq %%mm0, %0" : "=m"(*data)); break;
1117 case 1: asm("movq %%mm1, %0" : "=m"(*data)); break;
1118 case 2: asm("movq %%mm2, %0" : "=m"(*data)); break;
1119 case 3: asm("movq %%mm3, %0" : "=m"(*data)); break;
1120 case 4: asm("movq %%mm4, %0" : "=m"(*data)); break;
1121 case 5: asm("movq %%mm5, %0" : "=m"(*data)); break;
1122 case 6: asm("movq %%mm6, %0" : "=m"(*data)); break;
1123 case 7: asm("movq %%mm7, %0" : "=m"(*data)); break;
1124 default: BUG();
1125 }
1126 }
1127
1128 static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
1129 {
1130 switch (reg) {
1131 case 0: asm("movq %0, %%mm0" : : "m"(*data)); break;
1132 case 1: asm("movq %0, %%mm1" : : "m"(*data)); break;
1133 case 2: asm("movq %0, %%mm2" : : "m"(*data)); break;
1134 case 3: asm("movq %0, %%mm3" : : "m"(*data)); break;
1135 case 4: asm("movq %0, %%mm4" : : "m"(*data)); break;
1136 case 5: asm("movq %0, %%mm5" : : "m"(*data)); break;
1137 case 6: asm("movq %0, %%mm6" : : "m"(*data)); break;
1138 case 7: asm("movq %0, %%mm7" : : "m"(*data)); break;
1139 default: BUG();
1140 }
1141 }
1142
1143 static int em_fninit(struct x86_emulate_ctxt *ctxt)
1144 {
1145 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
1146 return emulate_nm(ctxt);
1147
1148 asm volatile("fninit");
1149 return X86EMUL_CONTINUE;
1150 }
1151
1152 static int em_fnstcw(struct x86_emulate_ctxt *ctxt)
1153 {
1154 u16 fcw;
1155
1156 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
1157 return emulate_nm(ctxt);
1158
1159 asm volatile("fnstcw %0": "+m"(fcw));
1160
1161 ctxt->dst.val = fcw;
1162
1163 return X86EMUL_CONTINUE;
1164 }
1165
1166 static int em_fnstsw(struct x86_emulate_ctxt *ctxt)
1167 {
1168 u16 fsw;
1169
1170 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
1171 return emulate_nm(ctxt);
1172
1173 asm volatile("fnstsw %0": "+m"(fsw));
1174
1175 ctxt->dst.val = fsw;
1176
1177 return X86EMUL_CONTINUE;
1178 }
1179
1180 static void decode_register_operand(struct x86_emulate_ctxt *ctxt,
1181 struct operand *op)
1182 {
1183 unsigned reg = ctxt->modrm_reg;
1184
1185 if (!(ctxt->d & ModRM))
1186 reg = (ctxt->b & 7) | ((ctxt->rex_prefix & 1) << 3);
1187
1188 if (ctxt->d & Sse) {
1189 op->type = OP_XMM;
1190 op->bytes = 16;
1191 op->addr.xmm = reg;
1192 read_sse_reg(ctxt, &op->vec_val, reg);
1193 return;
1194 }
1195 if (ctxt->d & Mmx) {
1196 reg &= 7;
1197 op->type = OP_MM;
1198 op->bytes = 8;
1199 op->addr.mm = reg;
1200 return;
1201 }
1202
1203 op->type = OP_REG;
1204 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
1205 op->addr.reg = decode_register(ctxt, reg, ctxt->d & ByteOp);
1206
1207 fetch_register_operand(op);
1208 op->orig_val = op->val;
1209 }
1210
1211 static void adjust_modrm_seg(struct x86_emulate_ctxt *ctxt, int base_reg)
1212 {
1213 if (base_reg == VCPU_REGS_RSP || base_reg == VCPU_REGS_RBP)
1214 ctxt->modrm_seg = VCPU_SREG_SS;
1215 }
1216
1217 static int decode_modrm(struct x86_emulate_ctxt *ctxt,
1218 struct operand *op)
1219 {
1220 u8 sib;
1221 int index_reg, base_reg, scale;
1222 int rc = X86EMUL_CONTINUE;
1223 ulong modrm_ea = 0;
1224
1225 ctxt->modrm_reg = ((ctxt->rex_prefix << 1) & 8); /* REX.R */
1226 index_reg = (ctxt->rex_prefix << 2) & 8; /* REX.X */
1227 base_reg = (ctxt->rex_prefix << 3) & 8; /* REX.B */
1228
1229 ctxt->modrm_mod = (ctxt->modrm & 0xc0) >> 6;
1230 ctxt->modrm_reg |= (ctxt->modrm & 0x38) >> 3;
1231 ctxt->modrm_rm = base_reg | (ctxt->modrm & 0x07);
1232 ctxt->modrm_seg = VCPU_SREG_DS;
1233
1234 if (ctxt->modrm_mod == 3 || (ctxt->d & NoMod)) {
1235 op->type = OP_REG;
1236 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
1237 op->addr.reg = decode_register(ctxt, ctxt->modrm_rm,
1238 ctxt->d & ByteOp);
1239 if (ctxt->d & Sse) {
1240 op->type = OP_XMM;
1241 op->bytes = 16;
1242 op->addr.xmm = ctxt->modrm_rm;
1243 read_sse_reg(ctxt, &op->vec_val, ctxt->modrm_rm);
1244 return rc;
1245 }
1246 if (ctxt->d & Mmx) {
1247 op->type = OP_MM;
1248 op->bytes = 8;
1249 op->addr.mm = ctxt->modrm_rm & 7;
1250 return rc;
1251 }
1252 fetch_register_operand(op);
1253 return rc;
1254 }
1255
1256 op->type = OP_MEM;
1257
1258 if (ctxt->ad_bytes == 2) {
1259 unsigned bx = reg_read(ctxt, VCPU_REGS_RBX);
1260 unsigned bp = reg_read(ctxt, VCPU_REGS_RBP);
1261 unsigned si = reg_read(ctxt, VCPU_REGS_RSI);
1262 unsigned di = reg_read(ctxt, VCPU_REGS_RDI);
1263
1264 /* 16-bit ModR/M decode. */
1265 switch (ctxt->modrm_mod) {
1266 case 0:
1267 if (ctxt->modrm_rm == 6)
1268 modrm_ea += insn_fetch(u16, ctxt);
1269 break;
1270 case 1:
1271 modrm_ea += insn_fetch(s8, ctxt);
1272 break;
1273 case 2:
1274 modrm_ea += insn_fetch(u16, ctxt);
1275 break;
1276 }
1277 switch (ctxt->modrm_rm) {
1278 case 0:
1279 modrm_ea += bx + si;
1280 break;
1281 case 1:
1282 modrm_ea += bx + di;
1283 break;
1284 case 2:
1285 modrm_ea += bp + si;
1286 break;
1287 case 3:
1288 modrm_ea += bp + di;
1289 break;
1290 case 4:
1291 modrm_ea += si;
1292 break;
1293 case 5:
1294 modrm_ea += di;
1295 break;
1296 case 6:
1297 if (ctxt->modrm_mod != 0)
1298 modrm_ea += bp;
1299 break;
1300 case 7:
1301 modrm_ea += bx;
1302 break;
1303 }
1304 if (ctxt->modrm_rm == 2 || ctxt->modrm_rm == 3 ||
1305 (ctxt->modrm_rm == 6 && ctxt->modrm_mod != 0))
1306 ctxt->modrm_seg = VCPU_SREG_SS;
1307 modrm_ea = (u16)modrm_ea;
1308 } else {
1309 /* 32/64-bit ModR/M decode. */
1310 if ((ctxt->modrm_rm & 7) == 4) {
1311 sib = insn_fetch(u8, ctxt);
1312 index_reg |= (sib >> 3) & 7;
1313 base_reg |= sib & 7;
1314 scale = sib >> 6;
1315
1316 if ((base_reg & 7) == 5 && ctxt->modrm_mod == 0)
1317 modrm_ea += insn_fetch(s32, ctxt);
1318 else {
1319 modrm_ea += reg_read(ctxt, base_reg);
1320 adjust_modrm_seg(ctxt, base_reg);
1321 /* Increment ESP on POP [ESP] */
1322 if ((ctxt->d & IncSP) &&
1323 base_reg == VCPU_REGS_RSP)
1324 modrm_ea += ctxt->op_bytes;
1325 }
1326 if (index_reg != 4)
1327 modrm_ea += reg_read(ctxt, index_reg) << scale;
1328 } else if ((ctxt->modrm_rm & 7) == 5 && ctxt->modrm_mod == 0) {
1329 modrm_ea += insn_fetch(s32, ctxt);
1330 if (ctxt->mode == X86EMUL_MODE_PROT64)
1331 ctxt->rip_relative = 1;
1332 } else {
1333 base_reg = ctxt->modrm_rm;
1334 modrm_ea += reg_read(ctxt, base_reg);
1335 adjust_modrm_seg(ctxt, base_reg);
1336 }
1337 switch (ctxt->modrm_mod) {
1338 case 1:
1339 modrm_ea += insn_fetch(s8, ctxt);
1340 break;
1341 case 2:
1342 modrm_ea += insn_fetch(s32, ctxt);
1343 break;
1344 }
1345 }
1346 op->addr.mem.ea = modrm_ea;
1347 if (ctxt->ad_bytes != 8)
1348 ctxt->memop.addr.mem.ea = (u32)ctxt->memop.addr.mem.ea;
1349
1350 done:
1351 return rc;
1352 }
1353
1354 static int decode_abs(struct x86_emulate_ctxt *ctxt,
1355 struct operand *op)
1356 {
1357 int rc = X86EMUL_CONTINUE;
1358
1359 op->type = OP_MEM;
1360 switch (ctxt->ad_bytes) {
1361 case 2:
1362 op->addr.mem.ea = insn_fetch(u16, ctxt);
1363 break;
1364 case 4:
1365 op->addr.mem.ea = insn_fetch(u32, ctxt);
1366 break;
1367 case 8:
1368 op->addr.mem.ea = insn_fetch(u64, ctxt);
1369 break;
1370 }
1371 done:
1372 return rc;
1373 }
1374
1375 static void fetch_bit_operand(struct x86_emulate_ctxt *ctxt)
1376 {
1377 long sv = 0, mask;
1378
1379 if (ctxt->dst.type == OP_MEM && ctxt->src.type == OP_REG) {
1380 mask = ~((long)ctxt->dst.bytes * 8 - 1);
1381
1382 if (ctxt->src.bytes == 2)
1383 sv = (s16)ctxt->src.val & (s16)mask;
1384 else if (ctxt->src.bytes == 4)
1385 sv = (s32)ctxt->src.val & (s32)mask;
1386 else
1387 sv = (s64)ctxt->src.val & (s64)mask;
1388
1389 ctxt->dst.addr.mem.ea = address_mask(ctxt,
1390 ctxt->dst.addr.mem.ea + (sv >> 3));
1391 }
1392
1393 /* only subword offset */
1394 ctxt->src.val &= (ctxt->dst.bytes << 3) - 1;
1395 }
1396
1397 static int read_emulated(struct x86_emulate_ctxt *ctxt,
1398 unsigned long addr, void *dest, unsigned size)
1399 {
1400 int rc;
1401 struct read_cache *mc = &ctxt->mem_read;
1402
1403 if (mc->pos < mc->end)
1404 goto read_cached;
1405
1406 WARN_ON((mc->end + size) >= sizeof(mc->data));
1407
1408 rc = ctxt->ops->read_emulated(ctxt, addr, mc->data + mc->end, size,
1409 &ctxt->exception);
1410 if (rc != X86EMUL_CONTINUE)
1411 return rc;
1412
1413 mc->end += size;
1414
1415 read_cached:
1416 memcpy(dest, mc->data + mc->pos, size);
1417 mc->pos += size;
1418 return X86EMUL_CONTINUE;
1419 }
1420
1421 static int segmented_read(struct x86_emulate_ctxt *ctxt,
1422 struct segmented_address addr,
1423 void *data,
1424 unsigned size)
1425 {
1426 int rc;
1427 ulong linear;
1428
1429 rc = linearize(ctxt, addr, size, false, &linear);
1430 if (rc != X86EMUL_CONTINUE)
1431 return rc;
1432 return read_emulated(ctxt, linear, data, size);
1433 }
1434
1435 static int segmented_write(struct x86_emulate_ctxt *ctxt,
1436 struct segmented_address addr,
1437 const void *data,
1438 unsigned size)
1439 {
1440 int rc;
1441 ulong linear;
1442
1443 rc = linearize(ctxt, addr, size, true, &linear);
1444 if (rc != X86EMUL_CONTINUE)
1445 return rc;
1446 return ctxt->ops->write_emulated(ctxt, linear, data, size,
1447 &ctxt->exception);
1448 }
1449
1450 static int segmented_cmpxchg(struct x86_emulate_ctxt *ctxt,
1451 struct segmented_address addr,
1452 const void *orig_data, const void *data,
1453 unsigned size)
1454 {
1455 int rc;
1456 ulong linear;
1457
1458 rc = linearize(ctxt, addr, size, true, &linear);
1459 if (rc != X86EMUL_CONTINUE)
1460 return rc;
1461 return ctxt->ops->cmpxchg_emulated(ctxt, linear, orig_data, data,
1462 size, &ctxt->exception);
1463 }
1464
1465 static int pio_in_emulated(struct x86_emulate_ctxt *ctxt,
1466 unsigned int size, unsigned short port,
1467 void *dest)
1468 {
1469 struct read_cache *rc = &ctxt->io_read;
1470
1471 if (rc->pos == rc->end) { /* refill pio read ahead */
1472 unsigned int in_page, n;
1473 unsigned int count = ctxt->rep_prefix ?
1474 address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) : 1;
1475 in_page = (ctxt->eflags & X86_EFLAGS_DF) ?
1476 offset_in_page(reg_read(ctxt, VCPU_REGS_RDI)) :
1477 PAGE_SIZE - offset_in_page(reg_read(ctxt, VCPU_REGS_RDI));
1478 n = min3(in_page, (unsigned int)sizeof(rc->data) / size, count);
1479 if (n == 0)
1480 n = 1;
1481 rc->pos = rc->end = 0;
1482 if (!ctxt->ops->pio_in_emulated(ctxt, size, port, rc->data, n))
1483 return 0;
1484 rc->end = n * size;
1485 }
1486
1487 if (ctxt->rep_prefix && (ctxt->d & String) &&
1488 !(ctxt->eflags & X86_EFLAGS_DF)) {
1489 ctxt->dst.data = rc->data + rc->pos;
1490 ctxt->dst.type = OP_MEM_STR;
1491 ctxt->dst.count = (rc->end - rc->pos) / size;
1492 rc->pos = rc->end;
1493 } else {
1494 memcpy(dest, rc->data + rc->pos, size);
1495 rc->pos += size;
1496 }
1497 return 1;
1498 }
1499
1500 static int read_interrupt_descriptor(struct x86_emulate_ctxt *ctxt,
1501 u16 index, struct desc_struct *desc)
1502 {
1503 struct desc_ptr dt;
1504 ulong addr;
1505
1506 ctxt->ops->get_idt(ctxt, &dt);
1507
1508 if (dt.size < index * 8 + 7)
1509 return emulate_gp(ctxt, index << 3 | 0x2);
1510
1511 addr = dt.address + index * 8;
1512 return linear_read_system(ctxt, addr, desc, sizeof(*desc));
1513 }
1514
1515 static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
1516 u16 selector, struct desc_ptr *dt)
1517 {
1518 const struct x86_emulate_ops *ops = ctxt->ops;
1519 u32 base3 = 0;
1520
1521 if (selector & 1 << 2) {
1522 struct desc_struct desc;
1523 u16 sel;
1524
1525 memset(dt, 0, sizeof(*dt));
1526 if (!ops->get_segment(ctxt, &sel, &desc, &base3,
1527 VCPU_SREG_LDTR))
1528 return;
1529
1530 dt->size = desc_limit_scaled(&desc); /* what if limit > 65535? */
1531 dt->address = get_desc_base(&desc) | ((u64)base3 << 32);
1532 } else
1533 ops->get_gdt(ctxt, dt);
1534 }
1535
1536 static int get_descriptor_ptr(struct x86_emulate_ctxt *ctxt,
1537 u16 selector, ulong *desc_addr_p)
1538 {
1539 struct desc_ptr dt;
1540 u16 index = selector >> 3;
1541 ulong addr;
1542
1543 get_descriptor_table_ptr(ctxt, selector, &dt);
1544
1545 if (dt.size < index * 8 + 7)
1546 return emulate_gp(ctxt, selector & 0xfffc);
1547
1548 addr = dt.address + index * 8;
1549
1550 #ifdef CONFIG_X86_64
1551 if (addr >> 32 != 0) {
1552 u64 efer = 0;
1553
1554 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
1555 if (!(efer & EFER_LMA))
1556 addr &= (u32)-1;
1557 }
1558 #endif
1559
1560 *desc_addr_p = addr;
1561 return X86EMUL_CONTINUE;
1562 }
1563
1564 /* allowed just for 8 bytes segments */
1565 static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1566 u16 selector, struct desc_struct *desc,
1567 ulong *desc_addr_p)
1568 {
1569 int rc;
1570
1571 rc = get_descriptor_ptr(ctxt, selector, desc_addr_p);
1572 if (rc != X86EMUL_CONTINUE)
1573 return rc;
1574
1575 return linear_read_system(ctxt, *desc_addr_p, desc, sizeof(*desc));
1576 }
1577
1578 /* allowed just for 8 bytes segments */
1579 static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1580 u16 selector, struct desc_struct *desc)
1581 {
1582 int rc;
1583 ulong addr;
1584
1585 rc = get_descriptor_ptr(ctxt, selector, &addr);
1586 if (rc != X86EMUL_CONTINUE)
1587 return rc;
1588
1589 return linear_write_system(ctxt, addr, desc, sizeof(*desc));
1590 }
1591
1592 static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1593 u16 selector, int seg, u8 cpl,
1594 enum x86_transfer_type transfer,
1595 struct desc_struct *desc)
1596 {
1597 struct desc_struct seg_desc, old_desc;
1598 u8 dpl, rpl;
1599 unsigned err_vec = GP_VECTOR;
1600 u32 err_code = 0;
1601 bool null_selector = !(selector & ~0x3); /* 0000-0003 are null */
1602 ulong desc_addr;
1603 int ret;
1604 u16 dummy;
1605 u32 base3 = 0;
1606
1607 memset(&seg_desc, 0, sizeof(seg_desc));
1608
1609 if (ctxt->mode == X86EMUL_MODE_REAL) {
1610 /* set real mode segment descriptor (keep limit etc. for
1611 * unreal mode) */
1612 ctxt->ops->get_segment(ctxt, &dummy, &seg_desc, NULL, seg);
1613 set_desc_base(&seg_desc, selector << 4);
1614 goto load;
1615 } else if (seg <= VCPU_SREG_GS && ctxt->mode == X86EMUL_MODE_VM86) {
1616 /* VM86 needs a clean new segment descriptor */
1617 set_desc_base(&seg_desc, selector << 4);
1618 set_desc_limit(&seg_desc, 0xffff);
1619 seg_desc.type = 3;
1620 seg_desc.p = 1;
1621 seg_desc.s = 1;
1622 seg_desc.dpl = 3;
1623 goto load;
1624 }
1625
1626 rpl = selector & 3;
1627
1628 /* TR should be in GDT only */
1629 if (seg == VCPU_SREG_TR && (selector & (1 << 2)))
1630 goto exception;
1631
1632 /* NULL selector is not valid for TR, CS and (except for long mode) SS */
1633 if (null_selector) {
1634 if (seg == VCPU_SREG_CS || seg == VCPU_SREG_TR)
1635 goto exception;
1636
1637 if (seg == VCPU_SREG_SS) {
1638 if (ctxt->mode != X86EMUL_MODE_PROT64 || rpl != cpl)
1639 goto exception;
1640
1641 /*
1642 * ctxt->ops->set_segment expects the CPL to be in
1643 * SS.DPL, so fake an expand-up 32-bit data segment.
1644 */
1645 seg_desc.type = 3;
1646 seg_desc.p = 1;
1647 seg_desc.s = 1;
1648 seg_desc.dpl = cpl;
1649 seg_desc.d = 1;
1650 seg_desc.g = 1;
1651 }
1652
1653 /* Skip all following checks */
1654 goto load;
1655 }
1656
1657 ret = read_segment_descriptor(ctxt, selector, &seg_desc, &desc_addr);
1658 if (ret != X86EMUL_CONTINUE)
1659 return ret;
1660
1661 err_code = selector & 0xfffc;
1662 err_vec = (transfer == X86_TRANSFER_TASK_SWITCH) ? TS_VECTOR :
1663 GP_VECTOR;
1664
1665 /* can't load system descriptor into segment selector */
1666 if (seg <= VCPU_SREG_GS && !seg_desc.s) {
1667 if (transfer == X86_TRANSFER_CALL_JMP)
1668 return X86EMUL_UNHANDLEABLE;
1669 goto exception;
1670 }
1671
1672 if (!seg_desc.p) {
1673 err_vec = (seg == VCPU_SREG_SS) ? SS_VECTOR : NP_VECTOR;
1674 goto exception;
1675 }
1676
1677 dpl = seg_desc.dpl;
1678
1679 switch (seg) {
1680 case VCPU_SREG_SS:
1681 /*
1682 * segment is not a writable data segment or segment
1683 * selector's RPL != CPL or segment selector's RPL != CPL
1684 */
1685 if (rpl != cpl || (seg_desc.type & 0xa) != 0x2 || dpl != cpl)
1686 goto exception;
1687 break;
1688 case VCPU_SREG_CS:
1689 if (!(seg_desc.type & 8))
1690 goto exception;
1691
1692 if (seg_desc.type & 4) {
1693 /* conforming */
1694 if (dpl > cpl)
1695 goto exception;
1696 } else {
1697 /* nonconforming */
1698 if (rpl > cpl || dpl != cpl)
1699 goto exception;
1700 }
1701 /* in long-mode d/b must be clear if l is set */
1702 if (seg_desc.d && seg_desc.l) {
1703 u64 efer = 0;
1704
1705 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
1706 if (efer & EFER_LMA)
1707 goto exception;
1708 }
1709
1710 /* CS(RPL) <- CPL */
1711 selector = (selector & 0xfffc) | cpl;
1712 break;
1713 case VCPU_SREG_TR:
1714 if (seg_desc.s || (seg_desc.type != 1 && seg_desc.type != 9))
1715 goto exception;
1716 old_desc = seg_desc;
1717 seg_desc.type |= 2; /* busy */
1718 ret = ctxt->ops->cmpxchg_emulated(ctxt, desc_addr, &old_desc, &seg_desc,
1719 sizeof(seg_desc), &ctxt->exception);
1720 if (ret != X86EMUL_CONTINUE)
1721 return ret;
1722 break;
1723 case VCPU_SREG_LDTR:
1724 if (seg_desc.s || seg_desc.type != 2)
1725 goto exception;
1726 break;
1727 default: /* DS, ES, FS, or GS */
1728 /*
1729 * segment is not a data or readable code segment or
1730 * ((segment is a data or nonconforming code segment)
1731 * and (both RPL and CPL > DPL))
1732 */
1733 if ((seg_desc.type & 0xa) == 0x8 ||
1734 (((seg_desc.type & 0xc) != 0xc) &&
1735 (rpl > dpl && cpl > dpl)))
1736 goto exception;
1737 break;
1738 }
1739
1740 if (seg_desc.s) {
1741 /* mark segment as accessed */
1742 if (!(seg_desc.type & 1)) {
1743 seg_desc.type |= 1;
1744 ret = write_segment_descriptor(ctxt, selector,
1745 &seg_desc);
1746 if (ret != X86EMUL_CONTINUE)
1747 return ret;
1748 }
1749 } else if (ctxt->mode == X86EMUL_MODE_PROT64) {
1750 ret = linear_read_system(ctxt, desc_addr+8, &base3, sizeof(base3));
1751 if (ret != X86EMUL_CONTINUE)
1752 return ret;
1753 if (emul_is_noncanonical_address(get_desc_base(&seg_desc) |
1754 ((u64)base3 << 32), ctxt))
1755 return emulate_gp(ctxt, 0);
1756 }
1757 load:
1758 ctxt->ops->set_segment(ctxt, selector, &seg_desc, base3, seg);
1759 if (desc)
1760 *desc = seg_desc;
1761 return X86EMUL_CONTINUE;
1762 exception:
1763 return emulate_exception(ctxt, err_vec, err_code, true);
1764 }
1765
1766 static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1767 u16 selector, int seg)
1768 {
1769 u8 cpl = ctxt->ops->cpl(ctxt);
1770
1771 /*
1772 * None of MOV, POP and LSS can load a NULL selector in CPL=3, but
1773 * they can load it at CPL<3 (Intel's manual says only LSS can,
1774 * but it's wrong).
1775 *
1776 * However, the Intel manual says that putting IST=1/DPL=3 in
1777 * an interrupt gate will result in SS=3 (the AMD manual instead
1778 * says it doesn't), so allow SS=3 in __load_segment_descriptor
1779 * and only forbid it here.
1780 */
1781 if (seg == VCPU_SREG_SS && selector == 3 &&
1782 ctxt->mode == X86EMUL_MODE_PROT64)
1783 return emulate_exception(ctxt, GP_VECTOR, 0, true);
1784
1785 return __load_segment_descriptor(ctxt, selector, seg, cpl,
1786 X86_TRANSFER_NONE, NULL);
1787 }
1788
1789 static void write_register_operand(struct operand *op)
1790 {
1791 return assign_register(op->addr.reg, op->val, op->bytes);
1792 }
1793
1794 static int writeback(struct x86_emulate_ctxt *ctxt, struct operand *op)
1795 {
1796 switch (op->type) {
1797 case OP_REG:
1798 write_register_operand(op);
1799 break;
1800 case OP_MEM:
1801 if (ctxt->lock_prefix)
1802 return segmented_cmpxchg(ctxt,
1803 op->addr.mem,
1804 &op->orig_val,
1805 &op->val,
1806 op->bytes);
1807 else
1808 return segmented_write(ctxt,
1809 op->addr.mem,
1810 &op->val,
1811 op->bytes);
1812 break;
1813 case OP_MEM_STR:
1814 return segmented_write(ctxt,
1815 op->addr.mem,
1816 op->data,
1817 op->bytes * op->count);
1818 break;
1819 case OP_XMM:
1820 write_sse_reg(ctxt, &op->vec_val, op->addr.xmm);
1821 break;
1822 case OP_MM:
1823 write_mmx_reg(ctxt, &op->mm_val, op->addr.mm);
1824 break;
1825 case OP_NONE:
1826 /* no writeback */
1827 break;
1828 default:
1829 break;
1830 }
1831 return X86EMUL_CONTINUE;
1832 }
1833
1834 static int push(struct x86_emulate_ctxt *ctxt, void *data, int bytes)
1835 {
1836 struct segmented_address addr;
1837
1838 rsp_increment(ctxt, -bytes);
1839 addr.ea = reg_read(ctxt, VCPU_REGS_RSP) & stack_mask(ctxt);
1840 addr.seg = VCPU_SREG_SS;
1841
1842 return segmented_write(ctxt, addr, data, bytes);
1843 }
1844
1845 static int em_push(struct x86_emulate_ctxt *ctxt)
1846 {
1847 /* Disable writeback. */
1848 ctxt->dst.type = OP_NONE;
1849 return push(ctxt, &ctxt->src.val, ctxt->op_bytes);
1850 }
1851
1852 static int emulate_pop(struct x86_emulate_ctxt *ctxt,
1853 void *dest, int len)
1854 {
1855 int rc;
1856 struct segmented_address addr;
1857
1858 addr.ea = reg_read(ctxt, VCPU_REGS_RSP) & stack_mask(ctxt);
1859 addr.seg = VCPU_SREG_SS;
1860 rc = segmented_read(ctxt, addr, dest, len);
1861 if (rc != X86EMUL_CONTINUE)
1862 return rc;
1863
1864 rsp_increment(ctxt, len);
1865 return rc;
1866 }
1867
1868 static int em_pop(struct x86_emulate_ctxt *ctxt)
1869 {
1870 return emulate_pop(ctxt, &ctxt->dst.val, ctxt->op_bytes);
1871 }
1872
1873 static int emulate_popf(struct x86_emulate_ctxt *ctxt,
1874 void *dest, int len)
1875 {
1876 int rc;
1877 unsigned long val, change_mask;
1878 int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> X86_EFLAGS_IOPL_BIT;
1879 int cpl = ctxt->ops->cpl(ctxt);
1880
1881 rc = emulate_pop(ctxt, &val, len);
1882 if (rc != X86EMUL_CONTINUE)
1883 return rc;
1884
1885 change_mask = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
1886 X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF |
1887 X86_EFLAGS_TF | X86_EFLAGS_DF | X86_EFLAGS_NT |
1888 X86_EFLAGS_AC | X86_EFLAGS_ID;
1889
1890 switch(ctxt->mode) {
1891 case X86EMUL_MODE_PROT64:
1892 case X86EMUL_MODE_PROT32:
1893 case X86EMUL_MODE_PROT16:
1894 if (cpl == 0)
1895 change_mask |= X86_EFLAGS_IOPL;
1896 if (cpl <= iopl)
1897 change_mask |= X86_EFLAGS_IF;
1898 break;
1899 case X86EMUL_MODE_VM86:
1900 if (iopl < 3)
1901 return emulate_gp(ctxt, 0);
1902 change_mask |= X86_EFLAGS_IF;
1903 break;
1904 default: /* real mode */
1905 change_mask |= (X86_EFLAGS_IOPL | X86_EFLAGS_IF);
1906 break;
1907 }
1908
1909 *(unsigned long *)dest =
1910 (ctxt->eflags & ~change_mask) | (val & change_mask);
1911
1912 return rc;
1913 }
1914
1915 static int em_popf(struct x86_emulate_ctxt *ctxt)
1916 {
1917 ctxt->dst.type = OP_REG;
1918 ctxt->dst.addr.reg = &ctxt->eflags;
1919 ctxt->dst.bytes = ctxt->op_bytes;
1920 return emulate_popf(ctxt, &ctxt->dst.val, ctxt->op_bytes);
1921 }
1922
1923 static int em_enter(struct x86_emulate_ctxt *ctxt)
1924 {
1925 int rc;
1926 unsigned frame_size = ctxt->src.val;
1927 unsigned nesting_level = ctxt->src2.val & 31;
1928 ulong rbp;
1929
1930 if (nesting_level)
1931 return X86EMUL_UNHANDLEABLE;
1932
1933 rbp = reg_read(ctxt, VCPU_REGS_RBP);
1934 rc = push(ctxt, &rbp, stack_size(ctxt));
1935 if (rc != X86EMUL_CONTINUE)
1936 return rc;
1937 assign_masked(reg_rmw(ctxt, VCPU_REGS_RBP), reg_read(ctxt, VCPU_REGS_RSP),
1938 stack_mask(ctxt));
1939 assign_masked(reg_rmw(ctxt, VCPU_REGS_RSP),
1940 reg_read(ctxt, VCPU_REGS_RSP) - frame_size,
1941 stack_mask(ctxt));
1942 return X86EMUL_CONTINUE;
1943 }
1944
1945 static int em_leave(struct x86_emulate_ctxt *ctxt)
1946 {
1947 assign_masked(reg_rmw(ctxt, VCPU_REGS_RSP), reg_read(ctxt, VCPU_REGS_RBP),
1948 stack_mask(ctxt));
1949 return emulate_pop(ctxt, reg_rmw(ctxt, VCPU_REGS_RBP), ctxt->op_bytes);
1950 }
1951
1952 static int em_push_sreg(struct x86_emulate_ctxt *ctxt)
1953 {
1954 int seg = ctxt->src2.val;
1955
1956 ctxt->src.val = get_segment_selector(ctxt, seg);
1957 if (ctxt->op_bytes == 4) {
1958 rsp_increment(ctxt, -2);
1959 ctxt->op_bytes = 2;
1960 }
1961
1962 return em_push(ctxt);
1963 }
1964
1965 static int em_pop_sreg(struct x86_emulate_ctxt *ctxt)
1966 {
1967 int seg = ctxt->src2.val;
1968 unsigned long selector;
1969 int rc;
1970
1971 rc = emulate_pop(ctxt, &selector, 2);
1972 if (rc != X86EMUL_CONTINUE)
1973 return rc;
1974
1975 if (ctxt->modrm_reg == VCPU_SREG_SS)
1976 ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
1977 if (ctxt->op_bytes > 2)
1978 rsp_increment(ctxt, ctxt->op_bytes - 2);
1979
1980 rc = load_segment_descriptor(ctxt, (u16)selector, seg);
1981 return rc;
1982 }
1983
1984 static int em_pusha(struct x86_emulate_ctxt *ctxt)
1985 {
1986 unsigned long old_esp = reg_read(ctxt, VCPU_REGS_RSP);
1987 int rc = X86EMUL_CONTINUE;
1988 int reg = VCPU_REGS_RAX;
1989
1990 while (reg <= VCPU_REGS_RDI) {
1991 (reg == VCPU_REGS_RSP) ?
1992 (ctxt->src.val = old_esp) : (ctxt->src.val = reg_read(ctxt, reg));
1993
1994 rc = em_push(ctxt);
1995 if (rc != X86EMUL_CONTINUE)
1996 return rc;
1997
1998 ++reg;
1999 }
2000
2001 return rc;
2002 }
2003
2004 static int em_pushf(struct x86_emulate_ctxt *ctxt)
2005 {
2006 ctxt->src.val = (unsigned long)ctxt->eflags & ~X86_EFLAGS_VM;
2007 return em_push(ctxt);
2008 }
2009
2010 static int em_popa(struct x86_emulate_ctxt *ctxt)
2011 {
2012 int rc = X86EMUL_CONTINUE;
2013 int reg = VCPU_REGS_RDI;
2014 u32 val;
2015
2016 while (reg >= VCPU_REGS_RAX) {
2017 if (reg == VCPU_REGS_RSP) {
2018 rsp_increment(ctxt, ctxt->op_bytes);
2019 --reg;
2020 }
2021
2022 rc = emulate_pop(ctxt, &val, ctxt->op_bytes);
2023 if (rc != X86EMUL_CONTINUE)
2024 break;
2025 assign_register(reg_rmw(ctxt, reg), val, ctxt->op_bytes);
2026 --reg;
2027 }
2028 return rc;
2029 }
2030
2031 static int __emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq)
2032 {
2033 const struct x86_emulate_ops *ops = ctxt->ops;
2034 int rc;
2035 struct desc_ptr dt;
2036 gva_t cs_addr;
2037 gva_t eip_addr;
2038 u16 cs, eip;
2039
2040 /* TODO: Add limit checks */
2041 ctxt->src.val = ctxt->eflags;
2042 rc = em_push(ctxt);
2043 if (rc != X86EMUL_CONTINUE)
2044 return rc;
2045
2046 ctxt->eflags &= ~(X86_EFLAGS_IF | X86_EFLAGS_TF | X86_EFLAGS_AC);
2047
2048 ctxt->src.val = get_segment_selector(ctxt, VCPU_SREG_CS);
2049 rc = em_push(ctxt);
2050 if (rc != X86EMUL_CONTINUE)
2051 return rc;
2052
2053 ctxt->src.val = ctxt->_eip;
2054 rc = em_push(ctxt);
2055 if (rc != X86EMUL_CONTINUE)
2056 return rc;
2057
2058 ops->get_idt(ctxt, &dt);
2059
2060 eip_addr = dt.address + (irq << 2);
2061 cs_addr = dt.address + (irq << 2) + 2;
2062
2063 rc = linear_read_system(ctxt, cs_addr, &cs, 2);
2064 if (rc != X86EMUL_CONTINUE)
2065 return rc;
2066
2067 rc = linear_read_system(ctxt, eip_addr, &eip, 2);
2068 if (rc != X86EMUL_CONTINUE)
2069 return rc;
2070
2071 rc = load_segment_descriptor(ctxt, cs, VCPU_SREG_CS);
2072 if (rc != X86EMUL_CONTINUE)
2073 return rc;
2074
2075 ctxt->_eip = eip;
2076
2077 return rc;
2078 }
2079
2080 int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq)
2081 {
2082 int rc;
2083
2084 invalidate_registers(ctxt);
2085 rc = __emulate_int_real(ctxt, irq);
2086 if (rc == X86EMUL_CONTINUE)
2087 writeback_registers(ctxt);
2088 return rc;
2089 }
2090
2091 static int emulate_int(struct x86_emulate_ctxt *ctxt, int irq)
2092 {
2093 switch(ctxt->mode) {
2094 case X86EMUL_MODE_REAL:
2095 return __emulate_int_real(ctxt, irq);
2096 case X86EMUL_MODE_VM86:
2097 case X86EMUL_MODE_PROT16:
2098 case X86EMUL_MODE_PROT32:
2099 case X86EMUL_MODE_PROT64:
2100 default:
2101 /* Protected mode interrupts unimplemented yet */
2102 return X86EMUL_UNHANDLEABLE;
2103 }
2104 }
2105
2106 static int emulate_iret_real(struct x86_emulate_ctxt *ctxt)
2107 {
2108 int rc = X86EMUL_CONTINUE;
2109 unsigned long temp_eip = 0;
2110 unsigned long temp_eflags = 0;
2111 unsigned long cs = 0;
2112 unsigned long mask = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
2113 X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_TF |
2114 X86_EFLAGS_IF | X86_EFLAGS_DF | X86_EFLAGS_OF |
2115 X86_EFLAGS_IOPL | X86_EFLAGS_NT | X86_EFLAGS_RF |
2116 X86_EFLAGS_AC | X86_EFLAGS_ID |
2117 X86_EFLAGS_FIXED;
2118 unsigned long vm86_mask = X86_EFLAGS_VM | X86_EFLAGS_VIF |
2119 X86_EFLAGS_VIP;
2120
2121 /* TODO: Add stack limit check */
2122
2123 rc = emulate_pop(ctxt, &temp_eip, ctxt->op_bytes);
2124
2125 if (rc != X86EMUL_CONTINUE)
2126 return rc;
2127
2128 if (temp_eip & ~0xffff)
2129 return emulate_gp(ctxt, 0);
2130
2131 rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
2132
2133 if (rc != X86EMUL_CONTINUE)
2134 return rc;
2135
2136 rc = emulate_pop(ctxt, &temp_eflags, ctxt->op_bytes);
2137
2138 if (rc != X86EMUL_CONTINUE)
2139 return rc;
2140
2141 rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS);
2142
2143 if (rc != X86EMUL_CONTINUE)
2144 return rc;
2145
2146 ctxt->_eip = temp_eip;
2147
2148 if (ctxt->op_bytes == 4)
2149 ctxt->eflags = ((temp_eflags & mask) | (ctxt->eflags & vm86_mask));
2150 else if (ctxt->op_bytes == 2) {
2151 ctxt->eflags &= ~0xffff;
2152 ctxt->eflags |= temp_eflags;
2153 }
2154
2155 ctxt->eflags &= ~EFLG_RESERVED_ZEROS_MASK; /* Clear reserved zeros */
2156 ctxt->eflags |= X86_EFLAGS_FIXED;
2157 ctxt->ops->set_nmi_mask(ctxt, false);
2158
2159 return rc;
2160 }
2161
2162 static int em_iret(struct x86_emulate_ctxt *ctxt)
2163 {
2164 switch(ctxt->mode) {
2165 case X86EMUL_MODE_REAL:
2166 return emulate_iret_real(ctxt);
2167 case X86EMUL_MODE_VM86:
2168 case X86EMUL_MODE_PROT16:
2169 case X86EMUL_MODE_PROT32:
2170 case X86EMUL_MODE_PROT64:
2171 default:
2172 /* iret from protected mode unimplemented yet */
2173 return X86EMUL_UNHANDLEABLE;
2174 }
2175 }
2176
2177 static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
2178 {
2179 int rc;
2180 unsigned short sel;
2181 struct desc_struct new_desc;
2182 u8 cpl = ctxt->ops->cpl(ctxt);
2183
2184 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
2185
2186 rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl,
2187 X86_TRANSFER_CALL_JMP,
2188 &new_desc);
2189 if (rc != X86EMUL_CONTINUE)
2190 return rc;
2191
2192 rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
2193 /* Error handling is not implemented. */
2194 if (rc != X86EMUL_CONTINUE)
2195 return X86EMUL_UNHANDLEABLE;
2196
2197 return rc;
2198 }
2199
2200 static int em_jmp_abs(struct x86_emulate_ctxt *ctxt)
2201 {
2202 return assign_eip_near(ctxt, ctxt->src.val);
2203 }
2204
2205 static int em_call_near_abs(struct x86_emulate_ctxt *ctxt)
2206 {
2207 int rc;
2208 long int old_eip;
2209
2210 old_eip = ctxt->_eip;
2211 rc = assign_eip_near(ctxt, ctxt->src.val);
2212 if (rc != X86EMUL_CONTINUE)
2213 return rc;
2214 ctxt->src.val = old_eip;
2215 rc = em_push(ctxt);
2216 return rc;
2217 }
2218
2219 static int em_cmpxchg8b(struct x86_emulate_ctxt *ctxt)
2220 {
2221 u64 old = ctxt->dst.orig_val64;
2222
2223 if (ctxt->dst.bytes == 16)
2224 return X86EMUL_UNHANDLEABLE;
2225
2226 if (((u32) (old >> 0) != (u32) reg_read(ctxt, VCPU_REGS_RAX)) ||
2227 ((u32) (old >> 32) != (u32) reg_read(ctxt, VCPU_REGS_RDX))) {
2228 *reg_write(ctxt, VCPU_REGS_RAX) = (u32) (old >> 0);
2229 *reg_write(ctxt, VCPU_REGS_RDX) = (u32) (old >> 32);
2230 ctxt->eflags &= ~X86_EFLAGS_ZF;
2231 } else {
2232 ctxt->dst.val64 = ((u64)reg_read(ctxt, VCPU_REGS_RCX) << 32) |
2233 (u32) reg_read(ctxt, VCPU_REGS_RBX);
2234
2235 ctxt->eflags |= X86_EFLAGS_ZF;
2236 }
2237 return X86EMUL_CONTINUE;
2238 }
2239
2240 static int em_ret(struct x86_emulate_ctxt *ctxt)
2241 {
2242 int rc;
2243 unsigned long eip;
2244
2245 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
2246 if (rc != X86EMUL_CONTINUE)
2247 return rc;
2248
2249 return assign_eip_near(ctxt, eip);
2250 }
2251
2252 static int em_ret_far(struct x86_emulate_ctxt *ctxt)
2253 {
2254 int rc;
2255 unsigned long eip, cs;
2256 int cpl = ctxt->ops->cpl(ctxt);
2257 struct desc_struct new_desc;
2258
2259 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
2260 if (rc != X86EMUL_CONTINUE)
2261 return rc;
2262 rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
2263 if (rc != X86EMUL_CONTINUE)
2264 return rc;
2265 /* Outer-privilege level return is not implemented */
2266 if (ctxt->mode >= X86EMUL_MODE_PROT16 && (cs & 3) > cpl)
2267 return X86EMUL_UNHANDLEABLE;
2268 rc = __load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS, cpl,
2269 X86_TRANSFER_RET,
2270 &new_desc);
2271 if (rc != X86EMUL_CONTINUE)
2272 return rc;
2273 rc = assign_eip_far(ctxt, eip, &new_desc);
2274 /* Error handling is not implemented. */
2275 if (rc != X86EMUL_CONTINUE)
2276 return X86EMUL_UNHANDLEABLE;
2277
2278 return rc;
2279 }
2280
2281 static int em_ret_far_imm(struct x86_emulate_ctxt *ctxt)
2282 {
2283 int rc;
2284
2285 rc = em_ret_far(ctxt);
2286 if (rc != X86EMUL_CONTINUE)
2287 return rc;
2288 rsp_increment(ctxt, ctxt->src.val);
2289 return X86EMUL_CONTINUE;
2290 }
2291
2292 static int em_cmpxchg(struct x86_emulate_ctxt *ctxt)
2293 {
2294 /* Save real source value, then compare EAX against destination. */
2295 ctxt->dst.orig_val = ctxt->dst.val;
2296 ctxt->dst.val = reg_read(ctxt, VCPU_REGS_RAX);
2297 ctxt->src.orig_val = ctxt->src.val;
2298 ctxt->src.val = ctxt->dst.orig_val;
2299 fastop(ctxt, em_cmp);
2300
2301 if (ctxt->eflags & X86_EFLAGS_ZF) {
2302 /* Success: write back to memory; no update of EAX */
2303 ctxt->src.type = OP_NONE;
2304 ctxt->dst.val = ctxt->src.orig_val;
2305 } else {
2306 /* Failure: write the value we saw to EAX. */
2307 ctxt->src.type = OP_REG;
2308 ctxt->src.addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX);
2309 ctxt->src.val = ctxt->dst.orig_val;
2310 /* Create write-cycle to dest by writing the same value */
2311 ctxt->dst.val = ctxt->dst.orig_val;
2312 }
2313 return X86EMUL_CONTINUE;
2314 }
2315
2316 static int em_lseg(struct x86_emulate_ctxt *ctxt)
2317 {
2318 int seg = ctxt->src2.val;
2319 unsigned short sel;
2320 int rc;
2321
2322 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
2323
2324 rc = load_segment_descriptor(ctxt, sel, seg);
2325 if (rc != X86EMUL_CONTINUE)
2326 return rc;
2327
2328 ctxt->dst.val = ctxt->src.val;
2329 return rc;
2330 }
2331
2332 static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt)
2333 {
2334 u32 eax, ebx, ecx, edx;
2335
2336 eax = 0x80000001;
2337 ecx = 0;
2338 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, false);
2339 return edx & bit(X86_FEATURE_LM);
2340 }
2341
2342 #define GET_SMSTATE(type, smbase, offset) \
2343 ({ \
2344 type __val; \
2345 int r = ctxt->ops->read_phys(ctxt, smbase + offset, &__val, \
2346 sizeof(__val)); \
2347 if (r != X86EMUL_CONTINUE) \
2348 return X86EMUL_UNHANDLEABLE; \
2349 __val; \
2350 })
2351
2352 static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags)
2353 {
2354 desc->g = (flags >> 23) & 1;
2355 desc->d = (flags >> 22) & 1;
2356 desc->l = (flags >> 21) & 1;
2357 desc->avl = (flags >> 20) & 1;
2358 desc->p = (flags >> 15) & 1;
2359 desc->dpl = (flags >> 13) & 3;
2360 desc->s = (flags >> 12) & 1;
2361 desc->type = (flags >> 8) & 15;
2362 }
2363
2364 static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, u64 smbase, int n)
2365 {
2366 struct desc_struct desc;
2367 int offset;
2368 u16 selector;
2369
2370 selector = GET_SMSTATE(u32, smbase, 0x7fa8 + n * 4);
2371
2372 if (n < 3)
2373 offset = 0x7f84 + n * 12;
2374 else
2375 offset = 0x7f2c + (n - 3) * 12;
2376
2377 set_desc_base(&desc, GET_SMSTATE(u32, smbase, offset + 8));
2378 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, offset + 4));
2379 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, offset));
2380 ctxt->ops->set_segment(ctxt, selector, &desc, 0, n);
2381 return X86EMUL_CONTINUE;
2382 }
2383
2384 static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, u64 smbase, int n)
2385 {
2386 struct desc_struct desc;
2387 int offset;
2388 u16 selector;
2389 u32 base3;
2390
2391 offset = 0x7e00 + n * 16;
2392
2393 selector = GET_SMSTATE(u16, smbase, offset);
2394 rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smbase, offset + 2) << 8);
2395 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, offset + 4));
2396 set_desc_base(&desc, GET_SMSTATE(u32, smbase, offset + 8));
2397 base3 = GET_SMSTATE(u32, smbase, offset + 12);
2398
2399 ctxt->ops->set_segment(ctxt, selector, &desc, base3, n);
2400 return X86EMUL_CONTINUE;
2401 }
2402
2403 static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
2404 u64 cr0, u64 cr3, u64 cr4)
2405 {
2406 int bad;
2407 u64 pcid;
2408
2409 /* In order to later set CR4.PCIDE, CR3[11:0] must be zero. */
2410 pcid = 0;
2411 if (cr4 & X86_CR4_PCIDE) {
2412 pcid = cr3 & 0xfff;
2413 cr3 &= ~0xfff;
2414 }
2415
2416 bad = ctxt->ops->set_cr(ctxt, 3, cr3);
2417 if (bad)
2418 return X86EMUL_UNHANDLEABLE;
2419
2420 /*
2421 * First enable PAE, long mode needs it before CR0.PG = 1 is set.
2422 * Then enable protected mode. However, PCID cannot be enabled
2423 * if EFER.LMA=0, so set it separately.
2424 */
2425 bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
2426 if (bad)
2427 return X86EMUL_UNHANDLEABLE;
2428
2429 bad = ctxt->ops->set_cr(ctxt, 0, cr0);
2430 if (bad)
2431 return X86EMUL_UNHANDLEABLE;
2432
2433 if (cr4 & X86_CR4_PCIDE) {
2434 bad = ctxt->ops->set_cr(ctxt, 4, cr4);
2435 if (bad)
2436 return X86EMUL_UNHANDLEABLE;
2437 if (pcid) {
2438 bad = ctxt->ops->set_cr(ctxt, 3, cr3 | pcid);
2439 if (bad)
2440 return X86EMUL_UNHANDLEABLE;
2441 }
2442
2443 }
2444
2445 return X86EMUL_CONTINUE;
2446 }
2447
2448 static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt, u64 smbase)
2449 {
2450 struct desc_struct desc;
2451 struct desc_ptr dt;
2452 u16 selector;
2453 u32 val, cr0, cr3, cr4;
2454 int i;
2455
2456 cr0 = GET_SMSTATE(u32, smbase, 0x7ffc);
2457 cr3 = GET_SMSTATE(u32, smbase, 0x7ff8);
2458 ctxt->eflags = GET_SMSTATE(u32, smbase, 0x7ff4) | X86_EFLAGS_FIXED;
2459 ctxt->_eip = GET_SMSTATE(u32, smbase, 0x7ff0);
2460
2461 for (i = 0; i < 8; i++)
2462 *reg_write(ctxt, i) = GET_SMSTATE(u32, smbase, 0x7fd0 + i * 4);
2463
2464 val = GET_SMSTATE(u32, smbase, 0x7fcc);
2465 ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1);
2466 val = GET_SMSTATE(u32, smbase, 0x7fc8);
2467 ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1);
2468
2469 selector = GET_SMSTATE(u32, smbase, 0x7fc4);
2470 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7f64));
2471 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7f60));
2472 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7f5c));
2473 ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR);
2474
2475 selector = GET_SMSTATE(u32, smbase, 0x7fc0);
2476 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7f80));
2477 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7f7c));
2478 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7f78));
2479 ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR);
2480
2481 dt.address = GET_SMSTATE(u32, smbase, 0x7f74);
2482 dt.size = GET_SMSTATE(u32, smbase, 0x7f70);
2483 ctxt->ops->set_gdt(ctxt, &dt);
2484
2485 dt.address = GET_SMSTATE(u32, smbase, 0x7f58);
2486 dt.size = GET_SMSTATE(u32, smbase, 0x7f54);
2487 ctxt->ops->set_idt(ctxt, &dt);
2488
2489 for (i = 0; i < 6; i++) {
2490 int r = rsm_load_seg_32(ctxt, smbase, i);
2491 if (r != X86EMUL_CONTINUE)
2492 return r;
2493 }
2494
2495 cr4 = GET_SMSTATE(u32, smbase, 0x7f14);
2496
2497 ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smbase, 0x7ef8));
2498
2499 return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
2500 }
2501
2502 static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt, u64 smbase)
2503 {
2504 struct desc_struct desc;
2505 struct desc_ptr dt;
2506 u64 val, cr0, cr3, cr4;
2507 u32 base3;
2508 u16 selector;
2509 int i, r;
2510
2511 for (i = 0; i < 16; i++)
2512 *reg_write(ctxt, i) = GET_SMSTATE(u64, smbase, 0x7ff8 - i * 8);
2513
2514 ctxt->_eip = GET_SMSTATE(u64, smbase, 0x7f78);
2515 ctxt->eflags = GET_SMSTATE(u32, smbase, 0x7f70) | X86_EFLAGS_FIXED;
2516
2517 val = GET_SMSTATE(u32, smbase, 0x7f68);
2518 ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1);
2519 val = GET_SMSTATE(u32, smbase, 0x7f60);
2520 ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1);
2521
2522 cr0 = GET_SMSTATE(u64, smbase, 0x7f58);
2523 cr3 = GET_SMSTATE(u64, smbase, 0x7f50);
2524 cr4 = GET_SMSTATE(u64, smbase, 0x7f48);
2525 ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smbase, 0x7f00));
2526 val = GET_SMSTATE(u64, smbase, 0x7ed0);
2527 ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA);
2528
2529 selector = GET_SMSTATE(u32, smbase, 0x7e90);
2530 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7e92) << 8);
2531 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7e94));
2532 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7e98));
2533 base3 = GET_SMSTATE(u32, smbase, 0x7e9c);
2534 ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR);
2535
2536 dt.size = GET_SMSTATE(u32, smbase, 0x7e84);
2537 dt.address = GET_SMSTATE(u64, smbase, 0x7e88);
2538 ctxt->ops->set_idt(ctxt, &dt);
2539
2540 selector = GET_SMSTATE(u32, smbase, 0x7e70);
2541 rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smbase, 0x7e72) << 8);
2542 set_desc_limit(&desc, GET_SMSTATE(u32, smbase, 0x7e74));
2543 set_desc_base(&desc, GET_SMSTATE(u32, smbase, 0x7e78));
2544 base3 = GET_SMSTATE(u32, smbase, 0x7e7c);
2545 ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR);
2546
2547 dt.size = GET_SMSTATE(u32, smbase, 0x7e64);
2548 dt.address = GET_SMSTATE(u64, smbase, 0x7e68);
2549 ctxt->ops->set_gdt(ctxt, &dt);
2550
2551 r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
2552 if (r != X86EMUL_CONTINUE)
2553 return r;
2554
2555 for (i = 0; i < 6; i++) {
2556 r = rsm_load_seg_64(ctxt, smbase, i);
2557 if (r != X86EMUL_CONTINUE)
2558 return r;
2559 }
2560
2561 return X86EMUL_CONTINUE;
2562 }
2563
2564 static int em_rsm(struct x86_emulate_ctxt *ctxt)
2565 {
2566 unsigned long cr0, cr4, efer;
2567 u64 smbase;
2568 int ret;
2569
2570 if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_MASK) == 0)
2571 return emulate_ud(ctxt);
2572
2573 /*
2574 * Get back to real mode, to prepare a safe state in which to load
2575 * CR0/CR3/CR4/EFER. It's all a bit more complicated if the vCPU
2576 * supports long mode.
2577 */
2578 cr4 = ctxt->ops->get_cr(ctxt, 4);
2579 if (emulator_has_longmode(ctxt)) {
2580 struct desc_struct cs_desc;
2581
2582 /* Zero CR4.PCIDE before CR0.PG. */
2583 if (cr4 & X86_CR4_PCIDE) {
2584 ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
2585 cr4 &= ~X86_CR4_PCIDE;
2586 }
2587
2588 /* A 32-bit code segment is required to clear EFER.LMA. */
2589 memset(&cs_desc, 0, sizeof(cs_desc));
2590 cs_desc.type = 0xb;
2591 cs_desc.s = cs_desc.g = cs_desc.p = 1;
2592 ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS);
2593 }
2594
2595 /* For the 64-bit case, this will clear EFER.LMA. */
2596 cr0 = ctxt->ops->get_cr(ctxt, 0);
2597 if (cr0 & X86_CR0_PE)
2598 ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
2599
2600 /* Now clear CR4.PAE (which must be done before clearing EFER.LME). */
2601 if (cr4 & X86_CR4_PAE)
2602 ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE);
2603
2604 /* And finally go back to 32-bit mode. */
2605 efer = 0;
2606 ctxt->ops->set_msr(ctxt, MSR_EFER, efer);
2607
2608 smbase = ctxt->ops->get_smbase(ctxt);
2609
2610 /*
2611 * Give pre_leave_smm() a chance to make ISA-specific changes to the
2612 * vCPU state (e.g. enter guest mode) before loading state from the SMM
2613 * state-save area.
2614 */
2615 if (ctxt->ops->pre_leave_smm(ctxt, smbase))
2616 return X86EMUL_UNHANDLEABLE;
2617
2618 if (emulator_has_longmode(ctxt))
2619 ret = rsm_load_state_64(ctxt, smbase + 0x8000);
2620 else
2621 ret = rsm_load_state_32(ctxt, smbase + 0x8000);
2622
2623 if (ret != X86EMUL_CONTINUE) {
2624 /* FIXME: should triple fault */
2625 return X86EMUL_UNHANDLEABLE;
2626 }
2627
2628 if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_INSIDE_NMI_MASK) == 0)
2629 ctxt->ops->set_nmi_mask(ctxt, false);
2630
2631 ctxt->ops->set_hflags(ctxt, ctxt->ops->get_hflags(ctxt) &
2632 ~(X86EMUL_SMM_INSIDE_NMI_MASK | X86EMUL_SMM_MASK));
2633 return X86EMUL_CONTINUE;
2634 }
2635
2636 static void
2637 setup_syscalls_segments(struct x86_emulate_ctxt *ctxt,
2638 struct desc_struct *cs, struct desc_struct *ss)
2639 {
2640 cs->l = 0; /* will be adjusted later */
2641 set_desc_base(cs, 0); /* flat segment */
2642 cs->g = 1; /* 4kb granularity */
2643 set_desc_limit(cs, 0xfffff); /* 4GB limit */
2644 cs->type = 0x0b; /* Read, Execute, Accessed */
2645 cs->s = 1;
2646 cs->dpl = 0; /* will be adjusted later */
2647 cs->p = 1;
2648 cs->d = 1;
2649 cs->avl = 0;
2650
2651 set_desc_base(ss, 0); /* flat segment */
2652 set_desc_limit(ss, 0xfffff); /* 4GB limit */
2653 ss->g = 1; /* 4kb granularity */
2654 ss->s = 1;
2655 ss->type = 0x03; /* Read/Write, Accessed */
2656 ss->d = 1; /* 32bit stack segment */
2657 ss->dpl = 0;
2658 ss->p = 1;
2659 ss->l = 0;
2660 ss->avl = 0;
2661 }
2662
2663 static bool vendor_intel(struct x86_emulate_ctxt *ctxt)
2664 {
2665 u32 eax, ebx, ecx, edx;
2666
2667 eax = ecx = 0;
2668 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, false);
2669 return ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx
2670 && ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx
2671 && edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx;
2672 }
2673
2674 static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
2675 {
2676 const struct x86_emulate_ops *ops = ctxt->ops;
2677 u32 eax, ebx, ecx, edx;
2678
2679 /*
2680 * syscall should always be enabled in longmode - so only become
2681 * vendor specific (cpuid) if other modes are active...
2682 */
2683 if (ctxt->mode == X86EMUL_MODE_PROT64)
2684 return true;
2685
2686 eax = 0x00000000;
2687 ecx = 0x00000000;
2688 ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, false);
2689 /*
2690 * Intel ("GenuineIntel")
2691 * remark: Intel CPUs only support "syscall" in 64bit
2692 * longmode. Also an 64bit guest with a
2693 * 32bit compat-app running will #UD !! While this
2694 * behaviour can be fixed (by emulating) into AMD
2695 * response - CPUs of AMD can't behave like Intel.
2696 */
2697 if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx &&
2698 ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx &&
2699 edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx)
2700 return false;
2701
2702 /* AMD ("AuthenticAMD") */
2703 if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx &&
2704 ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx &&
2705 edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx)
2706 return true;
2707
2708 /* AMD ("AMDisbetter!") */
2709 if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx &&
2710 ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx &&
2711 edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx)
2712 return true;
2713
2714 /* Hygon ("HygonGenuine") */
2715 if (ebx == X86EMUL_CPUID_VENDOR_HygonGenuine_ebx &&
2716 ecx == X86EMUL_CPUID_VENDOR_HygonGenuine_ecx &&
2717 edx == X86EMUL_CPUID_VENDOR_HygonGenuine_edx)
2718 return true;
2719
2720 /*
2721 * default: (not Intel, not AMD, not Hygon), apply Intel's
2722 * stricter rules...
2723 */
2724 return false;
2725 }
2726
2727 static int em_syscall(struct x86_emulate_ctxt *ctxt)
2728 {
2729 const struct x86_emulate_ops *ops = ctxt->ops;
2730 struct desc_struct cs, ss;
2731 u64 msr_data;
2732 u16 cs_sel, ss_sel;
2733 u64 efer = 0;
2734
2735 /* syscall is not available in real mode */
2736 if (ctxt->mode == X86EMUL_MODE_REAL ||
2737 ctxt->mode == X86EMUL_MODE_VM86)
2738 return emulate_ud(ctxt);
2739
2740 if (!(em_syscall_is_enabled(ctxt)))
2741 return emulate_ud(ctxt);
2742
2743 ops->get_msr(ctxt, MSR_EFER, &efer);
2744 setup_syscalls_segments(ctxt, &cs, &ss);
2745
2746 if (!(efer & EFER_SCE))
2747 return emulate_ud(ctxt);
2748
2749 ops->get_msr(ctxt, MSR_STAR, &msr_data);
2750 msr_data >>= 32;
2751 cs_sel = (u16)(msr_data & 0xfffc);
2752 ss_sel = (u16)(msr_data + 8);
2753
2754 if (efer & EFER_LMA) {
2755 cs.d = 0;
2756 cs.l = 1;
2757 }
2758 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
2759 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
2760
2761 *reg_write(ctxt, VCPU_REGS_RCX) = ctxt->_eip;
2762 if (efer & EFER_LMA) {
2763 #ifdef CONFIG_X86_64
2764 *reg_write(ctxt, VCPU_REGS_R11) = ctxt->eflags;
2765
2766 ops->get_msr(ctxt,
2767 ctxt->mode == X86EMUL_MODE_PROT64 ?
2768 MSR_LSTAR : MSR_CSTAR, &msr_data);
2769 ctxt->_eip = msr_data;
2770
2771 ops->get_msr(ctxt, MSR_SYSCALL_MASK, &msr_data);
2772 ctxt->eflags &= ~msr_data;
2773 ctxt->eflags |= X86_EFLAGS_FIXED;
2774 #endif
2775 } else {
2776 /* legacy mode */
2777 ops->get_msr(ctxt, MSR_STAR, &msr_data);
2778 ctxt->_eip = (u32)msr_data;
2779
2780 ctxt->eflags &= ~(X86_EFLAGS_VM | X86_EFLAGS_IF);
2781 }
2782
2783 ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0;
2784 return X86EMUL_CONTINUE;
2785 }
2786
2787 static int em_sysenter(struct x86_emulate_ctxt *ctxt)
2788 {
2789 const struct x86_emulate_ops *ops = ctxt->ops;
2790 struct desc_struct cs, ss;
2791 u64 msr_data;
2792 u16 cs_sel, ss_sel;
2793 u64 efer = 0;
2794
2795 ops->get_msr(ctxt, MSR_EFER, &efer);
2796 /* inject #GP if in real mode */
2797 if (ctxt->mode == X86EMUL_MODE_REAL)
2798 return emulate_gp(ctxt, 0);
2799
2800 /*
2801 * Not recognized on AMD in compat mode (but is recognized in legacy
2802 * mode).
2803 */
2804 if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA)
2805 && !vendor_intel(ctxt))
2806 return emulate_ud(ctxt);
2807
2808 /* sysenter/sysexit have not been tested in 64bit mode. */
2809 if (ctxt->mode == X86EMUL_MODE_PROT64)
2810 return X86EMUL_UNHANDLEABLE;
2811
2812 setup_syscalls_segments(ctxt, &cs, &ss);
2813
2814 ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data);
2815 if ((msr_data & 0xfffc) == 0x0)
2816 return emulate_gp(ctxt, 0);
2817
2818 ctxt->eflags &= ~(X86_EFLAGS_VM | X86_EFLAGS_IF);
2819 cs_sel = (u16)msr_data & ~SEGMENT_RPL_MASK;
2820 ss_sel = cs_sel + 8;
2821 if (efer & EFER_LMA) {
2822 cs.d = 0;
2823 cs.l = 1;
2824 }
2825
2826 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
2827 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
2828
2829 ops->get_msr(ctxt, MSR_IA32_SYSENTER_EIP, &msr_data);
2830 ctxt->_eip = (efer & EFER_LMA) ? msr_data : (u32)msr_data;
2831
2832 ops->get_msr(ctxt, MSR_IA32_SYSENTER_ESP, &msr_data);
2833 *reg_write(ctxt, VCPU_REGS_RSP) = (efer & EFER_LMA) ? msr_data :
2834 (u32)msr_data;
2835
2836 return X86EMUL_CONTINUE;
2837 }
2838
2839 static int em_sysexit(struct x86_emulate_ctxt *ctxt)
2840 {
2841 const struct x86_emulate_ops *ops = ctxt->ops;
2842 struct desc_struct cs, ss;
2843 u64 msr_data, rcx, rdx;
2844 int usermode;
2845 u16 cs_sel = 0, ss_sel = 0;
2846
2847 /* inject #GP if in real mode or Virtual 8086 mode */
2848 if (ctxt->mode == X86EMUL_MODE_REAL ||
2849 ctxt->mode == X86EMUL_MODE_VM86)
2850 return emulate_gp(ctxt, 0);
2851
2852 setup_syscalls_segments(ctxt, &cs, &ss);
2853
2854 if ((ctxt->rex_prefix & 0x8) != 0x0)
2855 usermode = X86EMUL_MODE_PROT64;
2856 else
2857 usermode = X86EMUL_MODE_PROT32;
2858
2859 rcx = reg_read(ctxt, VCPU_REGS_RCX);
2860 rdx = reg_read(ctxt, VCPU_REGS_RDX);
2861
2862 cs.dpl = 3;
2863 ss.dpl = 3;
2864 ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data);
2865 switch (usermode) {
2866 case X86EMUL_MODE_PROT32:
2867 cs_sel = (u16)(msr_data + 16);
2868 if ((msr_data & 0xfffc) == 0x0)
2869 return emulate_gp(ctxt, 0);
2870 ss_sel = (u16)(msr_data + 24);
2871 rcx = (u32)rcx;
2872 rdx = (u32)rdx;
2873 break;
2874 case X86EMUL_MODE_PROT64:
2875 cs_sel = (u16)(msr_data + 32);
2876 if (msr_data == 0x0)
2877 return emulate_gp(ctxt, 0);
2878 ss_sel = cs_sel + 8;
2879 cs.d = 0;
2880 cs.l = 1;
2881 if (emul_is_noncanonical_address(rcx, ctxt) ||
2882 emul_is_noncanonical_address(rdx, ctxt))
2883 return emulate_gp(ctxt, 0);
2884 break;
2885 }
2886 cs_sel |= SEGMENT_RPL_MASK;
2887 ss_sel |= SEGMENT_RPL_MASK;
2888
2889 ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
2890 ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
2891
2892 ctxt->_eip = rdx;
2893 *reg_write(ctxt, VCPU_REGS_RSP) = rcx;
2894
2895 return X86EMUL_CONTINUE;
2896 }
2897
2898 static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt)
2899 {
2900 int iopl;
2901 if (ctxt->mode == X86EMUL_MODE_REAL)
2902 return false;
2903 if (ctxt->mode == X86EMUL_MODE_VM86)
2904 return true;
2905 iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> X86_EFLAGS_IOPL_BIT;
2906 return ctxt->ops->cpl(ctxt) > iopl;
2907 }
2908
2909 #define VMWARE_PORT_VMPORT (0x5658)
2910 #define VMWARE_PORT_VMRPC (0x5659)
2911
2912 static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
2913 u16 port, u16 len)
2914 {
2915 const struct x86_emulate_ops *ops = ctxt->ops;
2916 struct desc_struct tr_seg;
2917 u32 base3;
2918 int r;
2919 u16 tr, io_bitmap_ptr, perm, bit_idx = port & 0x7;
2920 unsigned mask = (1 << len) - 1;
2921 unsigned long base;
2922
2923 /*
2924 * VMware allows access to these ports even if denied
2925 * by TSS I/O permission bitmap. Mimic behavior.
2926 */
2927 if (enable_vmware_backdoor &&
2928 ((port == VMWARE_PORT_VMPORT) || (port == VMWARE_PORT_VMRPC)))
2929 return true;
2930
2931 ops->get_segment(ctxt, &tr, &tr_seg, &base3, VCPU_SREG_TR);
2932 if (!tr_seg.p)
2933 return false;
2934 if (desc_limit_scaled(&tr_seg) < 103)
2935 return false;
2936 base = get_desc_base(&tr_seg);
2937 #ifdef CONFIG_X86_64
2938 base |= ((u64)base3) << 32;
2939 #endif
2940 r = ops->read_std(ctxt, base + 102, &io_bitmap_ptr, 2, NULL, true);
2941 if (r != X86EMUL_CONTINUE)
2942 return false;
2943 if (io_bitmap_ptr + port/8 > desc_limit_scaled(&tr_seg))
2944 return false;
2945 r = ops->read_std(ctxt, base + io_bitmap_ptr + port/8, &perm, 2, NULL, true);
2946 if (r != X86EMUL_CONTINUE)
2947 return false;
2948 if ((perm >> bit_idx) & mask)
2949 return false;
2950 return true;
2951 }
2952
2953 static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
2954 u16 port, u16 len)
2955 {
2956 if (ctxt->perm_ok)
2957 return true;
2958
2959 if (emulator_bad_iopl(ctxt))
2960 if (!emulator_io_port_access_allowed(ctxt, port, len))
2961 return false;
2962
2963 ctxt->perm_ok = true;
2964
2965 return true;
2966 }
2967
2968 static void string_registers_quirk(struct x86_emulate_ctxt *ctxt)
2969 {
2970 /*
2971 * Intel CPUs mask the counter and pointers in quite strange
2972 * manner when ECX is zero due to REP-string optimizations.
2973 */
2974 #ifdef CONFIG_X86_64
2975 if (ctxt->ad_bytes != 4 || !vendor_intel(ctxt))
2976 return;
2977
2978 *reg_write(ctxt, VCPU_REGS_RCX) = 0;
2979
2980 switch (ctxt->b) {
2981 case 0xa4: /* movsb */
2982 case 0xa5: /* movsd/w */
2983 *reg_rmw(ctxt, VCPU_REGS_RSI) &= (u32)-1;
2984 /* fall through */
2985 case 0xaa: /* stosb */
2986 case 0xab: /* stosd/w */
2987 *reg_rmw(ctxt, VCPU_REGS_RDI) &= (u32)-1;
2988 }
2989 #endif
2990 }
2991
2992 static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt,
2993 struct tss_segment_16 *tss)
2994 {
2995 tss->ip = ctxt->_eip;
2996 tss->flag = ctxt->eflags;
2997 tss->ax = reg_read(ctxt, VCPU_REGS_RAX);
2998 tss->cx = reg_read(ctxt, VCPU_REGS_RCX);
2999 tss->dx = reg_read(ctxt, VCPU_REGS_RDX);
3000 tss->bx = reg_read(ctxt, VCPU_REGS_RBX);
3001 tss->sp = reg_read(ctxt, VCPU_REGS_RSP);
3002 tss->bp = reg_read(ctxt, VCPU_REGS_RBP);
3003 tss->si = reg_read(ctxt, VCPU_REGS_RSI);
3004 tss->di = reg_read(ctxt, VCPU_REGS_RDI);
3005
3006 tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
3007 tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
3008 tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS);
3009 tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS);
3010 tss->ldt = get_segment_selector(ctxt, VCPU_SREG_LDTR);
3011 }
3012
3013 static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
3014 struct tss_segment_16 *tss)
3015 {
3016 int ret;
3017 u8 cpl;
3018
3019 ctxt->_eip = tss->ip;
3020 ctxt->eflags = tss->flag | 2;
3021 *reg_write(ctxt, VCPU_REGS_RAX) = tss->ax;
3022 *reg_write(ctxt, VCPU_REGS_RCX) = tss->cx;
3023 *reg_write(ctxt, VCPU_REGS_RDX) = tss->dx;
3024 *reg_write(ctxt, VCPU_REGS_RBX) = tss->bx;
3025 *reg_write(ctxt, VCPU_REGS_RSP) = tss->sp;
3026 *reg_write(ctxt, VCPU_REGS_RBP) = tss->bp;
3027 *reg_write(ctxt, VCPU_REGS_RSI) = tss->si;
3028 *reg_write(ctxt, VCPU_REGS_RDI) = tss->di;
3029
3030 /*
3031 * SDM says that segment selectors are loaded before segment
3032 * descriptors
3033 */
3034 set_segment_selector(ctxt, tss->ldt, VCPU_SREG_LDTR);
3035 set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
3036 set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
3037 set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
3038 set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
3039
3040 cpl = tss->cs & 3;
3041
3042 /*
3043 * Now load segment descriptors. If fault happens at this stage
3044 * it is handled in a context of new task
3045 */
3046 ret = __load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR, cpl,
3047 X86_TRANSFER_TASK_SWITCH, NULL);
3048 if (ret != X86EMUL_CONTINUE)
3049 return ret;
3050 ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl,
3051 X86_TRANSFER_TASK_SWITCH, NULL);
3052 if (ret != X86EMUL_CONTINUE)
3053 return ret;
3054 ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl,
3055 X86_TRANSFER_TASK_SWITCH, NULL);
3056 if (ret != X86EMUL_CONTINUE)
3057 return ret;
3058 ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl,
3059 X86_TRANSFER_TASK_SWITCH, NULL);
3060 if (ret != X86EMUL_CONTINUE)
3061 return ret;
3062 ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl,
3063 X86_TRANSFER_TASK_SWITCH, NULL);
3064 if (ret != X86EMUL_CONTINUE)
3065 return ret;
3066
3067 return X86EMUL_CONTINUE;
3068 }
3069
3070 static int task_switch_16(struct x86_emulate_ctxt *ctxt,
3071 u16 tss_selector, u16 old_tss_sel,
3072 ulong old_tss_base, struct desc_struct *new_desc)
3073 {
3074 struct tss_segment_16 tss_seg;
3075 int ret;
3076 u32 new_tss_base = get_desc_base(new_desc);
3077
3078 ret = linear_read_system(ctxt, old_tss_base, &tss_seg, sizeof(tss_seg));
3079 if (ret != X86EMUL_CONTINUE)
3080 return ret;
3081
3082 save_state_to_tss16(ctxt, &tss_seg);
3083
3084 ret = linear_write_system(ctxt, old_tss_base, &tss_seg, sizeof(tss_seg));
3085 if (ret != X86EMUL_CONTINUE)
3086 return ret;
3087
3088 ret = linear_read_system(ctxt, new_tss_base, &tss_seg, sizeof(tss_seg));
3089 if (ret != X86EMUL_CONTINUE)
3090 return ret;
3091
3092 if (old_tss_sel != 0xffff) {
3093 tss_seg.prev_task_link = old_tss_sel;
3094
3095 ret = linear_write_system(ctxt, new_tss_base,
3096 &tss_seg.prev_task_link,
3097 sizeof(tss_seg.prev_task_link));
3098 if (ret != X86EMUL_CONTINUE)
3099 return ret;
3100 }
3101
3102 return load_state_from_tss16(ctxt, &tss_seg);
3103 }
3104
3105 static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt,
3106 struct tss_segment_32 *tss)
3107 {
3108 /* CR3 and ldt selector are not saved intentionally */
3109 tss->eip = ctxt->_eip;
3110 tss->eflags = ctxt->eflags;
3111 tss->eax = reg_read(ctxt, VCPU_REGS_RAX);
3112 tss->ecx = reg_read(ctxt, VCPU_REGS_RCX);
3113 tss->edx = reg_read(ctxt, VCPU_REGS_RDX);
3114 tss->ebx = reg_read(ctxt, VCPU_REGS_RBX);
3115 tss->esp = reg_read(ctxt, VCPU_REGS_RSP);
3116 tss->ebp = reg_read(ctxt, VCPU_REGS_RBP);
3117 tss->esi = reg_read(ctxt, VCPU_REGS_RSI);
3118 tss->edi = reg_read(ctxt, VCPU_REGS_RDI);
3119
3120 tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
3121 tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
3122 tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS);
3123 tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS);
3124 tss->fs = get_segment_selector(ctxt, VCPU_SREG_FS);
3125 tss->gs = get_segment_selector(ctxt, VCPU_SREG_GS);
3126 }
3127
3128 static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
3129 struct tss_segment_32 *tss)
3130 {
3131 int ret;
3132 u8 cpl;
3133
3134 if (ctxt->ops->set_cr(ctxt, 3, tss->cr3))
3135 return emulate_gp(ctxt, 0);
3136 ctxt->_eip = tss->eip;
3137 ctxt->eflags = tss->eflags | 2;
3138
3139 /* General purpose registers */
3140 *reg_write(ctxt, VCPU_REGS_RAX) = tss->eax;
3141 *reg_write(ctxt, VCPU_REGS_RCX) = tss->ecx;
3142 *reg_write(ctxt, VCPU_REGS_RDX) = tss->edx;
3143 *reg_write(ctxt, VCPU_REGS_RBX) = tss->ebx;
3144 *reg_write(ctxt, VCPU_REGS_RSP) = tss->esp;
3145 *reg_write(ctxt, VCPU_REGS_RBP) = tss->ebp;
3146 *reg_write(ctxt, VCPU_REGS_RSI) = tss->esi;
3147 *reg_write(ctxt, VCPU_REGS_RDI) = tss->edi;
3148
3149 /*
3150 * SDM says that segment selectors are loaded before segment
3151 * descriptors. This is important because CPL checks will
3152 * use CS.RPL.
3153 */
3154 set_segment_selector(ctxt, tss->ldt_selector, VCPU_SREG_LDTR);
3155 set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
3156 set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
3157 set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
3158 set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
3159 set_segment_selector(ctxt, tss->fs, VCPU_SREG_FS);
3160 set_segment_selector(ctxt, tss->gs, VCPU_SREG_GS);
3161
3162 /*
3163 * If we're switching between Protected Mode and VM86, we need to make
3164 * sure to update the mode before loading the segment descriptors so
3165 * that the selectors are interpreted correctly.
3166 */
3167 if (ctxt->eflags & X86_EFLAGS_VM) {
3168 ctxt->mode = X86EMUL_MODE_VM86;
3169 cpl = 3;
3170 } else {
3171 ctxt->mode = X86EMUL_MODE_PROT32;
3172 cpl = tss->cs & 3;
3173 }
3174
3175 /*
3176 * Now load segment descriptors. If fault happenes at this stage
3177 * it is handled in a context of new task
3178 */
3179 ret = __load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR,
3180 cpl, X86_TRANSFER_TASK_SWITCH, NULL);
3181 if (ret != X86EMUL_CONTINUE)
3182 return ret;
3183 ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl,
3184 X86_TRANSFER_TASK_SWITCH, NULL);
3185 if (ret != X86EMUL_CONTINUE)
3186 return ret;
3187 ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl,
3188 X86_TRANSFER_TASK_SWITCH, NULL);
3189 if (ret != X86EMUL_CONTINUE)
3190 return ret;
3191 ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl,
3192 X86_TRANSFER_TASK_SWITCH, NULL);
3193 if (ret != X86EMUL_CONTINUE)
3194 return ret;
3195 ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl,
3196 X86_TRANSFER_TASK_SWITCH, NULL);
3197 if (ret != X86EMUL_CONTINUE)
3198 return ret;
3199 ret = __load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS, cpl,
3200 X86_TRANSFER_TASK_SWITCH, NULL);
3201 if (ret != X86EMUL_CONTINUE)
3202 return ret;
3203 ret = __load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS, cpl,
3204 X86_TRANSFER_TASK_SWITCH, NULL);
3205
3206 return ret;
3207 }
3208
3209 static int task_switch_32(struct x86_emulate_ctxt *ctxt,
3210 u16 tss_selector, u16 old_tss_sel,
3211 ulong old_tss_base, struct desc_struct *new_desc)
3212 {
3213 struct tss_segment_32 tss_seg;
3214 int ret;
3215 u32 new_tss_base = get_desc_base(new_desc);
3216 u32 eip_offset = offsetof(struct tss_segment_32, eip);
3217 u32 ldt_sel_offset = offsetof(struct tss_segment_32, ldt_selector);
3218
3219 ret = linear_read_system(ctxt, old_tss_base, &tss_seg, sizeof(tss_seg));
3220 if (ret != X86EMUL_CONTINUE)
3221 return ret;
3222
3223 save_state_to_tss32(ctxt, &tss_seg);
3224
3225 /* Only GP registers and segment selectors are saved */
3226 ret = linear_write_system(ctxt, old_tss_base + eip_offset, &tss_seg.eip,
3227 ldt_sel_offset - eip_offset);
3228 if (ret != X86EMUL_CONTINUE)
3229 return ret;
3230
3231 ret = linear_read_system(ctxt, new_tss_base, &tss_seg, sizeof(tss_seg));
3232 if (ret != X86EMUL_CONTINUE)
3233 return ret;
3234
3235 if (old_tss_sel != 0xffff) {
3236 tss_seg.prev_task_link = old_tss_sel;
3237
3238 ret = linear_write_system(ctxt, new_tss_base,
3239 &tss_seg.prev_task_link,
3240 sizeof(tss_seg.prev_task_link));
3241 if (ret != X86EMUL_CONTINUE)
3242 return ret;
3243 }
3244
3245 return load_state_from_tss32(ctxt, &tss_seg);
3246 }
3247
3248 static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
3249 u16 tss_selector, int idt_index, int reason,
3250 bool has_error_code, u32 error_code)
3251 {
3252 const struct x86_emulate_ops *ops = ctxt->ops;
3253 struct desc_struct curr_tss_desc, next_tss_desc;
3254 int ret;
3255 u16 old_tss_sel = get_segment_selector(ctxt, VCPU_SREG_TR);
3256 ulong old_tss_base =
3257 ops->get_cached_segment_base(ctxt, VCPU_SREG_TR);
3258 u32 desc_limit;
3259 ulong desc_addr, dr7;
3260
3261 /* FIXME: old_tss_base == ~0 ? */
3262
3263 ret = read_segment_descriptor(ctxt, tss_selector, &next_tss_desc, &desc_addr);
3264 if (ret != X86EMUL_CONTINUE)
3265 return ret;
3266 ret = read_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc, &desc_addr);
3267 if (ret != X86EMUL_CONTINUE)
3268 return ret;
3269
3270 /* FIXME: check that next_tss_desc is tss */
3271
3272 /*
3273 * Check privileges. The three cases are task switch caused by...
3274 *
3275 * 1. jmp/call/int to task gate: Check against DPL of the task gate
3276 * 2. Exception/IRQ/iret: No check is performed
3277 * 3. jmp/call to TSS/task-gate: No check is performed since the
3278 * hardware checks it before exiting.
3279 */
3280 if (reason == TASK_SWITCH_GATE) {
3281 if (idt_index != -1) {
3282 /* Software interrupts */
3283 struct desc_struct task_gate_desc;
3284 int dpl;
3285
3286 ret = read_interrupt_descriptor(ctxt, idt_index,
3287 &task_gate_desc);
3288 if (ret != X86EMUL_CONTINUE)
3289 return ret;
3290
3291 dpl = task_gate_desc.dpl;
3292 if ((tss_selector & 3) > dpl || ops->cpl(ctxt) > dpl)
3293 return emulate_gp(ctxt, (idt_index << 3) | 0x2);
3294 }
3295 }
3296
3297 desc_limit = desc_limit_scaled(&next_tss_desc);
3298 if (!next_tss_desc.p ||
3299 ((desc_limit < 0x67 && (next_tss_desc.type & 8)) ||
3300 desc_limit < 0x2b)) {
3301 return emulate_ts(ctxt, tss_selector & 0xfffc);
3302 }
3303
3304 if (reason == TASK_SWITCH_IRET || reason == TASK_SWITCH_JMP) {
3305 curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */
3306 write_segment_descriptor(ctxt, old_tss_sel, &curr_tss_desc);
3307 }
3308
3309 if (reason == TASK_SWITCH_IRET)
3310 ctxt->eflags = ctxt->eflags & ~X86_EFLAGS_NT;
3311
3312 /* set back link to prev task only if NT bit is set in eflags
3313 note that old_tss_sel is not used after this point */
3314 if (reason != TASK_SWITCH_CALL && reason != TASK_SWITCH_GATE)
3315 old_tss_sel = 0xffff;
3316
3317 if (next_tss_desc.type & 8)
3318 ret = task_switch_32(ctxt, tss_selector, old_tss_sel,
3319 old_tss_base, &next_tss_desc);
3320 else
3321 ret = task_switch_16(ctxt, tss_selector, old_tss_sel,
3322 old_tss_base, &next_tss_desc);
3323 if (ret != X86EMUL_CONTINUE)
3324 return ret;
3325
3326 if (reason == TASK_SWITCH_CALL || reason == TASK_SWITCH_GATE)
3327 ctxt->eflags = ctxt->eflags | X86_EFLAGS_NT;
3328
3329 if (reason != TASK_SWITCH_IRET) {
3330 next_tss_desc.type |= (1 << 1); /* set busy flag */
3331 write_segment_descriptor(ctxt, tss_selector, &next_tss_desc);
3332 }
3333
3334 ops->set_cr(ctxt, 0, ops->get_cr(ctxt, 0) | X86_CR0_TS);
3335 ops->set_segment(ctxt, tss_selector, &next_tss_desc, 0, VCPU_SREG_TR);
3336
3337 if (has_error_code) {
3338 ctxt->op_bytes = ctxt->ad_bytes = (next_tss_desc.type & 8) ? 4 : 2;
3339 ctxt->lock_prefix = 0;
3340 ctxt->src.val = (unsigned long) error_code;
3341 ret = em_push(ctxt);
3342 }
3343
3344 ops->get_dr(ctxt, 7, &dr7);
3345 ops->set_dr(ctxt, 7, dr7 & ~(DR_LOCAL_ENABLE_MASK | DR_LOCAL_SLOWDOWN));
3346
3347 return ret;
3348 }
3349
3350 int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
3351 u16 tss_selector, int idt_index, int reason,
3352 bool has_error_code, u32 error_code)
3353 {
3354 int rc;
3355
3356 invalidate_registers(ctxt);
3357 ctxt->_eip = ctxt->eip;
3358 ctxt->dst.type = OP_NONE;
3359
3360 rc = emulator_do_task_switch(ctxt, tss_selector, idt_index, reason,
3361 has_error_code, error_code);
3362
3363 if (rc == X86EMUL_CONTINUE) {
3364 ctxt->eip = ctxt->_eip;
3365 writeback_registers(ctxt);
3366 }
3367
3368 return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
3369 }
3370
3371 static void string_addr_inc(struct x86_emulate_ctxt *ctxt, int reg,
3372 struct operand *op)
3373 {
3374 int df = (ctxt->eflags & X86_EFLAGS_DF) ? -op->count : op->count;
3375
3376 register_address_increment(ctxt, reg, df * op->bytes);
3377 op->addr.mem.ea = register_address(ctxt, reg);
3378 }
3379
3380 static int em_das(struct x86_emulate_ctxt *ctxt)
3381 {
3382 u8 al, old_al;
3383 bool af, cf, old_cf;
3384
3385 cf = ctxt->eflags & X86_EFLAGS_CF;
3386 al = ctxt->dst.val;
3387
3388 old_al = al;
3389 old_cf = cf;
3390 cf = false;
3391 af = ctxt->eflags & X86_EFLAGS_AF;
3392 if ((al & 0x0f) > 9 || af) {
3393 al -= 6;
3394 cf = old_cf | (al >= 250);
3395 af = true;
3396 } else {
3397 af = false;
3398 }
3399 if (old_al > 0x99 || old_cf) {
3400 al -= 0x60;
3401 cf = true;
3402 }
3403
3404 ctxt->dst.val = al;
3405 /* Set PF, ZF, SF */
3406 ctxt->src.type = OP_IMM;
3407 ctxt->src.val = 0;
3408 ctxt->src.bytes = 1;
3409 fastop(ctxt, em_or);
3410 ctxt->eflags &= ~(X86_EFLAGS_AF | X86_EFLAGS_CF);
3411 if (cf)
3412 ctxt->eflags |= X86_EFLAGS_CF;
3413 if (af)
3414 ctxt->eflags |= X86_EFLAGS_AF;
3415 return X86EMUL_CONTINUE;
3416 }
3417
3418 static int em_aam(struct x86_emulate_ctxt *ctxt)
3419 {
3420 u8 al, ah;
3421
3422 if (ctxt->src.val == 0)
3423 return emulate_de(ctxt);
3424
3425 al = ctxt->dst.val & 0xff;
3426 ah = al / ctxt->src.val;
3427 al %= ctxt->src.val;
3428
3429 ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al | (ah << 8);
3430
3431 /* Set PF, ZF, SF */
3432 ctxt->src.type = OP_IMM;
3433 ctxt->src.val = 0;
3434 ctxt->src.bytes = 1;
3435 fastop(ctxt, em_or);
3436
3437 return X86EMUL_CONTINUE;
3438 }
3439
3440 static int em_aad(struct x86_emulate_ctxt *ctxt)
3441 {
3442 u8 al = ctxt->dst.val & 0xff;
3443 u8 ah = (ctxt->dst.val >> 8) & 0xff;
3444
3445 al = (al + (ah * ctxt->src.val)) & 0xff;
3446
3447 ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al;
3448
3449 /* Set PF, ZF, SF */
3450 ctxt->src.type = OP_IMM;
3451 ctxt->src.val = 0;
3452 ctxt->src.bytes = 1;
3453 fastop(ctxt, em_or);
3454
3455 return X86EMUL_CONTINUE;
3456 }
3457
3458 static int em_call(struct x86_emulate_ctxt *ctxt)
3459 {
3460 int rc;
3461 long rel = ctxt->src.val;
3462
3463 ctxt->src.val = (unsigned long)ctxt->_eip;
3464 rc = jmp_rel(ctxt, rel);
3465 if (rc != X86EMUL_CONTINUE)
3466 return rc;
3467 return em_push(ctxt);
3468 }
3469
3470 static int em_call_far(struct x86_emulate_ctxt *ctxt)
3471 {
3472 u16 sel, old_cs;
3473 ulong old_eip;
3474 int rc;
3475 struct desc_struct old_desc, new_desc;
3476 const struct x86_emulate_ops *ops = ctxt->ops;
3477 int cpl = ctxt->ops->cpl(ctxt);
3478 enum x86emul_mode prev_mode = ctxt->mode;
3479
3480 old_eip = ctxt->_eip;
3481 ops->get_segment(ctxt, &old_cs, &old_desc, NULL, VCPU_SREG_CS);
3482
3483 memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
3484 rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl,
3485 X86_TRANSFER_CALL_JMP, &new_desc);
3486 if (rc != X86EMUL_CONTINUE)
3487 return rc;
3488
3489 rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
3490 if (rc != X86EMUL_CONTINUE)
3491 goto fail;
3492
3493 ctxt->src.val = old_cs;
3494 rc = em_push(ctxt);
3495 if (rc != X86EMUL_CONTINUE)
3496 goto fail;
3497
3498 ctxt->src.val = old_eip;
3499 rc = em_push(ctxt);
3500 /* If we failed, we tainted the memory, but the very least we should
3501 restore cs */
3502 if (rc != X86EMUL_CONTINUE) {
3503 pr_warn_once("faulting far call emulation tainted memory\n");
3504 goto fail;
3505 }
3506 return rc;
3507 fail:
3508 ops->set_segment(ctxt, old_cs, &old_desc, 0, VCPU_SREG_CS);
3509 ctxt->mode = prev_mode;
3510 return rc;
3511
3512 }
3513
3514 static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
3515 {
3516 int rc;
3517 unsigned long eip;
3518
3519 rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
3520 if (rc != X86EMUL_CONTINUE)
3521 return rc;
3522 rc = assign_eip_near(ctxt, eip);
3523 if (rc != X86EMUL_CONTINUE)
3524 return rc;
3525 rsp_increment(ctxt, ctxt->src.val);
3526 return X86EMUL_CONTINUE;
3527 }
3528
3529 static int em_xchg(struct x86_emulate_ctxt *ctxt)
3530 {
3531 /* Write back the register source. */
3532 ctxt->src.val = ctxt->dst.val;
3533 write_register_operand(&ctxt->src);
3534
3535 /* Write back the memory destination with implicit LOCK prefix. */
3536 ctxt->dst.val = ctxt->src.orig_val;
3537 ctxt->lock_prefix = 1;
3538 return X86EMUL_CONTINUE;
3539 }
3540
3541 static int em_imul_3op(struct x86_emulate_ctxt *ctxt)
3542 {
3543 ctxt->dst.val = ctxt->src2.val;
3544 return fastop(ctxt, em_imul);
3545 }
3546
3547 static int em_cwd(struct x86_emulate_ctxt *ctxt)
3548 {
3549 ctxt->dst.type = OP_REG;
3550 ctxt->dst.bytes = ctxt->src.bytes;
3551 ctxt->dst.addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX);
3552 ctxt->dst.val = ~((ctxt->src.val >> (ctxt->src.bytes * 8 - 1)) - 1);
3553
3554 return X86EMUL_CONTINUE;
3555 }
3556
3557 static int em_rdpid(struct x86_emulate_ctxt *ctxt)
3558 {
3559 u64 tsc_aux = 0;
3560
3561 if (ctxt->ops->get_msr(ctxt, MSR_TSC_AUX, &tsc_aux))
3562 return emulate_gp(ctxt, 0);
3563 ctxt->dst.val = tsc_aux;
3564 return X86EMUL_CONTINUE;
3565 }
3566
3567 static int em_rdtsc(struct x86_emulate_ctxt *ctxt)
3568 {
3569 u64 tsc = 0;
3570
3571 ctxt->ops->get_msr(ctxt, MSR_IA32_TSC, &tsc);
3572 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)tsc;
3573 *reg_write(ctxt, VCPU_REGS_RDX) = tsc >> 32;
3574 return X86EMUL_CONTINUE;
3575 }
3576
3577 static int em_rdpmc(struct x86_emulate_ctxt *ctxt)
3578 {
3579 u64 pmc;
3580
3581 if (ctxt->ops->read_pmc(ctxt, reg_read(ctxt, VCPU_REGS_RCX), &pmc))
3582 return emulate_gp(ctxt, 0);
3583 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)pmc;
3584 *reg_write(ctxt, VCPU_REGS_RDX) = pmc >> 32;
3585 return X86EMUL_CONTINUE;
3586 }
3587
3588 static int em_mov(struct x86_emulate_ctxt *ctxt)
3589 {
3590 memcpy(ctxt->dst.valptr, ctxt->src.valptr, sizeof(ctxt->src.valptr));
3591 return X86EMUL_CONTINUE;
3592 }
3593
3594 #define FFL(x) bit(X86_FEATURE_##x)
3595
3596 static int em_movbe(struct x86_emulate_ctxt *ctxt)
3597 {
3598 u32 ebx, ecx, edx, eax = 1;
3599 u16 tmp;
3600
3601 /*
3602 * Check MOVBE is set in the guest-visible CPUID leaf.
3603 */
3604 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, false);
3605 if (!(ecx & FFL(MOVBE)))
3606 return emulate_ud(ctxt);
3607
3608 switch (ctxt->op_bytes) {
3609 case 2:
3610 /*
3611 * From MOVBE definition: "...When the operand size is 16 bits,
3612 * the upper word of the destination register remains unchanged
3613 * ..."
3614 *
3615 * Both casting ->valptr and ->val to u16 breaks strict aliasing
3616 * rules so we have to do the operation almost per hand.
3617 */
3618 tmp = (u16)ctxt->src.val;
3619 ctxt->dst.val &= ~0xffffUL;
3620 ctxt->dst.val |= (unsigned long)swab16(tmp);
3621 break;
3622 case 4:
3623 ctxt->dst.val = swab32((u32)ctxt->src.val);
3624 break;
3625 case 8:
3626 ctxt->dst.val = swab64(ctxt->src.val);
3627 break;
3628 default:
3629 BUG();
3630 }
3631 return X86EMUL_CONTINUE;
3632 }
3633
3634 static int em_cr_write(struct x86_emulate_ctxt *ctxt)
3635 {
3636 if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val))
3637 return emulate_gp(ctxt, 0);
3638
3639 /* Disable writeback. */
3640 ctxt->dst.type = OP_NONE;
3641 return X86EMUL_CONTINUE;
3642 }
3643
3644 static int em_dr_write(struct x86_emulate_ctxt *ctxt)
3645 {
3646 unsigned long val;
3647
3648 if (ctxt->mode == X86EMUL_MODE_PROT64)
3649 val = ctxt->src.val & ~0ULL;
3650 else
3651 val = ctxt->src.val & ~0U;
3652
3653 /* #UD condition is already handled. */
3654 if (ctxt->ops->set_dr(ctxt, ctxt->modrm_reg, val) < 0)
3655 return emulate_gp(ctxt, 0);
3656
3657 /* Disable writeback. */
3658 ctxt->dst.type = OP_NONE;
3659 return X86EMUL_CONTINUE;
3660 }
3661
3662 static int em_wrmsr(struct x86_emulate_ctxt *ctxt)
3663 {
3664 u64 msr_data;
3665
3666 msr_data = (u32)reg_read(ctxt, VCPU_REGS_RAX)
3667 | ((u64)reg_read(ctxt, VCPU_REGS_RDX) << 32);
3668 if (ctxt->ops->set_msr(ctxt, reg_read(ctxt, VCPU_REGS_RCX), msr_data))
3669 return emulate_gp(ctxt, 0);
3670
3671 return X86EMUL_CONTINUE;
3672 }
3673
3674 static int em_rdmsr(struct x86_emulate_ctxt *ctxt)
3675 {
3676 u64 msr_data;
3677
3678 if (ctxt->ops->get_msr(ctxt, reg_read(ctxt, VCPU_REGS_RCX), &msr_data))
3679 return emulate_gp(ctxt, 0);
3680
3681 *reg_write(ctxt, VCPU_REGS_RAX) = (u32)msr_data;
3682 *reg_write(ctxt, VCPU_REGS_RDX) = msr_data >> 32;
3683 return X86EMUL_CONTINUE;
3684 }
3685
3686 static int em_store_sreg(struct x86_emulate_ctxt *ctxt, int segment)
3687 {
3688 if (segment > VCPU_SREG_GS &&
3689 (ctxt->ops->get_cr(ctxt, 4) & X86_CR4_UMIP) &&
3690 ctxt->ops->cpl(ctxt) > 0)
3691 return emulate_gp(ctxt, 0);
3692
3693 ctxt->dst.val = get_segment_selector(ctxt, segment);
3694 if (ctxt->dst.bytes == 4 && ctxt->dst.type == OP_MEM)
3695 ctxt->dst.bytes = 2;
3696 return X86EMUL_CONTINUE;
3697 }
3698
3699 static int em_mov_rm_sreg(struct x86_emulate_ctxt *ctxt)
3700 {
3701 if (ctxt->modrm_reg > VCPU_SREG_GS)
3702 return emulate_ud(ctxt);
3703
3704 return em_store_sreg(ctxt, ctxt->modrm_reg);
3705 }
3706
3707 static int em_mov_sreg_rm(struct x86_emulate_ctxt *ctxt)
3708 {
3709 u16 sel = ctxt->src.val;
3710
3711 if (ctxt->modrm_reg == VCPU_SREG_CS || ctxt->modrm_reg > VCPU_SREG_GS)
3712 return emulate_ud(ctxt);
3713
3714 if (ctxt->modrm_reg == VCPU_SREG_SS)
3715 ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
3716
3717 /* Disable writeback. */
3718 ctxt->dst.type = OP_NONE;
3719 return load_segment_descriptor(ctxt, sel, ctxt->modrm_reg);
3720 }
3721
3722 static int em_sldt(struct x86_emulate_ctxt *ctxt)
3723 {
3724 return em_store_sreg(ctxt, VCPU_SREG_LDTR);
3725 }
3726
3727 static int em_lldt(struct x86_emulate_ctxt *ctxt)
3728 {
3729 u16 sel = ctxt->src.val;
3730
3731 /* Disable writeback. */
3732 ctxt->dst.type = OP_NONE;
3733 return load_segment_descriptor(ctxt, sel, VCPU_SREG_LDTR);
3734 }
3735
3736 static int em_str(struct x86_emulate_ctxt *ctxt)
3737 {
3738 return em_store_sreg(ctxt, VCPU_SREG_TR);
3739 }
3740
3741 static int em_ltr(struct x86_emulate_ctxt *ctxt)
3742 {
3743 u16 sel = ctxt->src.val;
3744
3745 /* Disable writeback. */
3746 ctxt->dst.type = OP_NONE;
3747 return load_segment_descriptor(ctxt, sel, VCPU_SREG_TR);
3748 }
3749
3750 static int em_invlpg(struct x86_emulate_ctxt *ctxt)
3751 {
3752 int rc;
3753 ulong linear;
3754
3755 rc = linearize(ctxt, ctxt->src.addr.mem, 1, false, &linear);
3756 if (rc == X86EMUL_CONTINUE)
3757 ctxt->ops->invlpg(ctxt, linear);
3758 /* Disable writeback. */
3759 ctxt->dst.type = OP_NONE;
3760 return X86EMUL_CONTINUE;
3761 }
3762
3763 static int em_clts(struct x86_emulate_ctxt *ctxt)
3764 {
3765 ulong cr0;
3766
3767 cr0 = ctxt->ops->get_cr(ctxt, 0);
3768 cr0 &= ~X86_CR0_TS;
3769 ctxt->ops->set_cr(ctxt, 0, cr0);
3770 return X86EMUL_CONTINUE;
3771 }
3772
3773 static int em_hypercall(struct x86_emulate_ctxt *ctxt)
3774 {
3775 int rc = ctxt->ops->fix_hypercall(ctxt);
3776
3777 if (rc != X86EMUL_CONTINUE)
3778 return rc;
3779
3780 /* Let the processor re-execute the fixed hypercall */
3781 ctxt->_eip = ctxt->eip;
3782 /* Disable writeback. */
3783 ctxt->dst.type = OP_NONE;
3784 return X86EMUL_CONTINUE;
3785 }
3786
3787 static int emulate_store_desc_ptr(struct x86_emulate_ctxt *ctxt,
3788 void (*get)(struct x86_emulate_ctxt *ctxt,
3789 struct desc_ptr *ptr))
3790 {
3791 struct desc_ptr desc_ptr;
3792
3793 if ((ctxt->ops->get_cr(ctxt, 4) & X86_CR4_UMIP) &&
3794 ctxt->ops->cpl(ctxt) > 0)
3795 return emulate_gp(ctxt, 0);
3796
3797 if (ctxt->mode == X86EMUL_MODE_PROT64)
3798 ctxt->op_bytes = 8;
3799 get(ctxt, &desc_ptr);
3800 if (ctxt->op_bytes == 2) {
3801 ctxt->op_bytes = 4;
3802 desc_ptr.address &= 0x00ffffff;
3803 }
3804 /* Disable writeback. */
3805 ctxt->dst.type = OP_NONE;
3806 return segmented_write_std(ctxt, ctxt->dst.addr.mem,
3807 &desc_ptr, 2 + ctxt->op_bytes);
3808 }
3809
3810 static int em_sgdt(struct x86_emulate_ctxt *ctxt)
3811 {
3812 return emulate_store_desc_ptr(ctxt, ctxt->ops->get_gdt);
3813 }
3814
3815 static int em_sidt(struct x86_emulate_ctxt *ctxt)
3816 {
3817 return emulate_store_desc_ptr(ctxt, ctxt->ops->get_idt);
3818 }
3819
3820 static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt)
3821 {
3822 struct desc_ptr desc_ptr;
3823 int rc;
3824
3825 if (ctxt->mode == X86EMUL_MODE_PROT64)
3826 ctxt->op_bytes = 8;
3827 rc = read_descriptor(ctxt, ctxt->src.addr.mem,
3828 &desc_ptr.size, &desc_ptr.address,
3829 ctxt->op_bytes);
3830 if (rc != X86EMUL_CONTINUE)
3831 return rc;
3832 if (ctxt->mode == X86EMUL_MODE_PROT64 &&
3833 emul_is_noncanonical_address(desc_ptr.address, ctxt))
3834 return emulate_gp(ctxt, 0);
3835 if (lgdt)
3836 ctxt->ops->set_gdt(ctxt, &desc_ptr);
3837 else
3838 ctxt->ops->set_idt(ctxt, &desc_ptr);
3839 /* Disable writeback. */
3840 ctxt->dst.type = OP_NONE;
3841 return X86EMUL_CONTINUE;
3842 }
3843
3844 static int em_lgdt(struct x86_emulate_ctxt *ctxt)
3845 {
3846 return em_lgdt_lidt(ctxt, true);
3847 }
3848
3849 static int em_lidt(struct x86_emulate_ctxt *ctxt)
3850 {
3851 return em_lgdt_lidt(ctxt, false);
3852 }
3853
3854 static int em_smsw(struct x86_emulate_ctxt *ctxt)
3855 {
3856 if ((ctxt->ops->get_cr(ctxt, 4) & X86_CR4_UMIP) &&
3857 ctxt->ops->cpl(ctxt) > 0)
3858 return emulate_gp(ctxt, 0);
3859
3860 if (ctxt->dst.type == OP_MEM)
3861 ctxt->dst.bytes = 2;
3862 ctxt->dst.val = ctxt->ops->get_cr(ctxt, 0);
3863 return X86EMUL_CONTINUE;
3864 }
3865
3866 static int em_lmsw(struct x86_emulate_ctxt *ctxt)
3867 {
3868 ctxt->ops->set_cr(ctxt, 0, (ctxt->ops->get_cr(ctxt, 0) & ~0x0eul)
3869 | (ctxt->src.val & 0x0f));
3870 ctxt->dst.type = OP_NONE;
3871 return X86EMUL_CONTINUE;
3872 }
3873
3874 static int em_loop(struct x86_emulate_ctxt *ctxt)
3875 {
3876 int rc = X86EMUL_CONTINUE;
3877
3878 register_address_increment(ctxt, VCPU_REGS_RCX, -1);
3879 if ((address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) != 0) &&
3880 (ctxt->b == 0xe2 || test_cc(ctxt->b ^ 0x5, ctxt->eflags)))
3881 rc = jmp_rel(ctxt, ctxt->src.val);
3882
3883 return rc;
3884 }
3885
3886 static int em_jcxz(struct x86_emulate_ctxt *ctxt)
3887 {
3888 int rc = X86EMUL_CONTINUE;
3889
3890 if (address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) == 0)
3891 rc = jmp_rel(ctxt, ctxt->src.val);
3892
3893 return rc;
3894 }
3895
3896 static int em_in(struct x86_emulate_ctxt *ctxt)
3897 {
3898 if (!pio_in_emulated(ctxt, ctxt->dst.bytes, ctxt->src.val,
3899 &ctxt->dst.val))
3900 return X86EMUL_IO_NEEDED;
3901
3902 return X86EMUL_CONTINUE;
3903 }
3904
3905 static int em_out(struct x86_emulate_ctxt *ctxt)
3906 {
3907 ctxt->ops->pio_out_emulated(ctxt, ctxt->src.bytes, ctxt->dst.val,
3908 &ctxt->src.val, 1);
3909 /* Disable writeback. */
3910 ctxt->dst.type = OP_NONE;
3911 return X86EMUL_CONTINUE;
3912 }
3913
3914 static int em_cli(struct x86_emulate_ctxt *ctxt)
3915 {
3916 if (emulator_bad_iopl(ctxt))
3917 return emulate_gp(ctxt, 0);
3918
3919 ctxt->eflags &= ~X86_EFLAGS_IF;
3920 return X86EMUL_CONTINUE;
3921 }
3922
3923 static int em_sti(struct x86_emulate_ctxt *ctxt)
3924 {
3925 if (emulator_bad_iopl(ctxt))
3926 return emulate_gp(ctxt, 0);
3927
3928 ctxt->interruptibility = KVM_X86_SHADOW_INT_STI;
3929 ctxt->eflags |= X86_EFLAGS_IF;
3930 return X86EMUL_CONTINUE;
3931 }
3932
3933 static int em_cpuid(struct x86_emulate_ctxt *ctxt)
3934 {
3935 u32 eax, ebx, ecx, edx;
3936 u64 msr = 0;
3937
3938 ctxt->ops->get_msr(ctxt, MSR_MISC_FEATURES_ENABLES, &msr);
3939 if (msr & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT &&
3940 ctxt->ops->cpl(ctxt)) {
3941 return emulate_gp(ctxt, 0);
3942 }
3943
3944 eax = reg_read(ctxt, VCPU_REGS_RAX);
3945 ecx = reg_read(ctxt, VCPU_REGS_RCX);
3946 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
3947 *reg_write(ctxt, VCPU_REGS_RAX) = eax;
3948 *reg_write(ctxt, VCPU_REGS_RBX) = ebx;
3949 *reg_write(ctxt, VCPU_REGS_RCX) = ecx;
3950 *reg_write(ctxt, VCPU_REGS_RDX) = edx;
3951 return X86EMUL_CONTINUE;
3952 }
3953
3954 static int em_sahf(struct x86_emulate_ctxt *ctxt)
3955 {
3956 u32 flags;
3957
3958 flags = X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF |
3959 X86_EFLAGS_SF;
3960 flags &= *reg_rmw(ctxt, VCPU_REGS_RAX) >> 8;
3961
3962 ctxt->eflags &= ~0xffUL;
3963 ctxt->eflags |= flags | X86_EFLAGS_FIXED;
3964 return X86EMUL_CONTINUE;
3965 }
3966
3967 static int em_lahf(struct x86_emulate_ctxt *ctxt)
3968 {
3969 *reg_rmw(ctxt, VCPU_REGS_RAX) &= ~0xff00UL;
3970 *reg_rmw(ctxt, VCPU_REGS_RAX) |= (ctxt->eflags & 0xff) << 8;
3971 return X86EMUL_CONTINUE;
3972 }
3973
3974 static int em_bswap(struct x86_emulate_ctxt *ctxt)
3975 {
3976 switch (ctxt->op_bytes) {
3977 #ifdef CONFIG_X86_64
3978 case 8:
3979 asm("bswap %0" : "+r"(ctxt->dst.val));
3980 break;
3981 #endif
3982 default:
3983 asm("bswap %0" : "+r"(*(u32 *)&ctxt->dst.val));
3984 break;
3985 }
3986 return X86EMUL_CONTINUE;
3987 }
3988
3989 static int em_clflush(struct x86_emulate_ctxt *ctxt)
3990 {
3991 /* emulating clflush regardless of cpuid */
3992 return X86EMUL_CONTINUE;
3993 }
3994
3995 static int em_movsxd(struct x86_emulate_ctxt *ctxt)
3996 {
3997 ctxt->dst.val = (s32) ctxt->src.val;
3998 return X86EMUL_CONTINUE;
3999 }
4000
4001 static int check_fxsr(struct x86_emulate_ctxt *ctxt)
4002 {
4003 u32 eax = 1, ebx, ecx = 0, edx;
4004
4005 ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, false);
4006 if (!(edx & FFL(FXSR)))
4007 return emulate_ud(ctxt);
4008
4009 if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
4010 return emulate_nm(ctxt);
4011
4012 /*
4013 * Don't emulate a case that should never be hit, instead of working
4014 * around a lack of fxsave64/fxrstor64 on old compilers.
4015 */
4016 if (ctxt->mode >= X86EMUL_MODE_PROT64)
4017 return X86EMUL_UNHANDLEABLE;
4018
4019 return X86EMUL_CONTINUE;
4020 }
4021
4022 /*
4023 * Hardware doesn't save and restore XMM 0-7 without CR4.OSFXSR, but does save
4024 * and restore MXCSR.
4025 */
4026 static size_t __fxstate_size(int nregs)
4027 {
4028 return offsetof(struct fxregs_state, xmm_space[0]) + nregs * 16;
4029 }
4030
4031 static inline size_t fxstate_size(struct x86_emulate_ctxt *ctxt)
4032 {
4033 bool cr4_osfxsr;
4034 if (ctxt->mode == X86EMUL_MODE_PROT64)
4035 return __fxstate_size(16);
4036
4037 cr4_osfxsr = ctxt->ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR;
4038 return __fxstate_size(cr4_osfxsr ? 8 : 0);
4039 }
4040
4041 /*
4042 * FXSAVE and FXRSTOR have 4 different formats depending on execution mode,
4043 * 1) 16 bit mode
4044 * 2) 32 bit mode
4045 * - like (1), but FIP and FDP (foo) are only 16 bit. At least Intel CPUs
4046 * preserve whole 32 bit values, though, so (1) and (2) are the same wrt.
4047 * save and restore
4048 * 3) 64-bit mode with REX.W prefix
4049 * - like (2), but XMM 8-15 are being saved and restored
4050 * 4) 64-bit mode without REX.W prefix
4051 * - like (3), but FIP and FDP are 64 bit
4052 *
4053 * Emulation uses (3) for (1) and (2) and preserves XMM 8-15 to reach the
4054 * desired result. (4) is not emulated.
4055 *
4056 * Note: Guest and host CPUID.(EAX=07H,ECX=0H):EBX[bit 13] (deprecate FPU CS
4057 * and FPU DS) should match.
4058 */
4059 static int em_fxsave(struct x86_emulate_ctxt *ctxt)
4060 {
4061 struct fxregs_state fx_state;
4062 int rc;
4063
4064 rc = check_fxsr(ctxt);
4065 if (rc != X86EMUL_CONTINUE)
4066 return rc;
4067
4068 rc = asm_safe("fxsave %[fx]", , [fx] "+m"(fx_state));
4069
4070 if (rc != X86EMUL_CONTINUE)
4071 return rc;
4072
4073 return segmented_write_std(ctxt, ctxt->memop.addr.mem, &fx_state,
4074 fxstate_size(ctxt));
4075 }
4076
4077 /*
4078 * FXRSTOR might restore XMM registers not provided by the guest. Fill
4079 * in the host registers (via FXSAVE) instead, so they won't be modified.
4080 * (preemption has to stay disabled until FXRSTOR).
4081 *
4082 * Use noinline to keep the stack for other functions called by callers small.
4083 */
4084 static noinline int fxregs_fixup(struct fxregs_state *fx_state,
4085 const size_t used_size)
4086 {
4087 struct fxregs_state fx_tmp;
4088 int rc;
4089
4090 rc = asm_safe("fxsave %[fx]", , [fx] "+m"(fx_tmp));
4091 memcpy((void *)fx_state + used_size, (void *)&fx_tmp + used_size,
4092 __fxstate_size(16) - used_size);
4093
4094 return rc;
4095 }
4096
4097 static int em_fxrstor(struct x86_emulate_ctxt *ctxt)
4098 {
4099 struct fxregs_state fx_state;
4100 int rc;
4101 size_t size;
4102
4103 rc = check_fxsr(ctxt);
4104 if (rc != X86EMUL_CONTINUE)
4105 return rc;
4106
4107 size = fxstate_size(ctxt);
4108 rc = segmented_read_std(ctxt, ctxt->memop.addr.mem, &fx_state, size);
4109 if (rc != X86EMUL_CONTINUE)
4110 return rc;
4111
4112 if (size < __fxstate_size(16)) {
4113 rc = fxregs_fixup(&fx_state, size);
4114 if (rc != X86EMUL_CONTINUE)
4115 goto out;
4116 }
4117
4118 if (fx_state.mxcsr >> 16) {
4119 rc = emulate_gp(ctxt, 0);
4120 goto out;
4121 }
4122
4123 if (rc == X86EMUL_CONTINUE)
4124 rc = asm_safe("fxrstor %[fx]", : [fx] "m"(fx_state));
4125
4126 out:
4127 return rc;
4128 }
4129
4130 static bool valid_cr(int nr)
4131 {
4132 switch (nr) {
4133 case 0:
4134 case 2 ... 4:
4135 case 8:
4136 return true;
4137 default:
4138 return false;
4139 }
4140 }
4141
4142 static int check_cr_read(struct x86_emulate_ctxt *ctxt)
4143 {
4144 if (!valid_cr(ctxt->modrm_reg))
4145 return emulate_ud(ctxt);
4146
4147 return X86EMUL_CONTINUE;
4148 }
4149
4150 static int check_cr_write(struct x86_emulate_ctxt *ctxt)
4151 {
4152 u64 new_val = ctxt->src.val64;
4153 int cr = ctxt->modrm_reg;
4154 u64 efer = 0;
4155
4156 static u64 cr_reserved_bits[] = {
4157 0xffffffff00000000ULL,
4158 0, 0, 0, /* CR3 checked later */
4159 CR4_RESERVED_BITS,
4160 0, 0, 0,
4161 CR8_RESERVED_BITS,
4162 };
4163
4164 if (!valid_cr(cr))
4165 return emulate_ud(ctxt);
4166
4167 if (new_val & cr_reserved_bits[cr])
4168 return emulate_gp(ctxt, 0);
4169
4170 switch (cr) {
4171 case 0: {
4172 u64 cr4;
4173 if (((new_val & X86_CR0_PG) && !(new_val & X86_CR0_PE)) ||
4174 ((new_val & X86_CR0_NW) && !(new_val & X86_CR0_CD)))
4175 return emulate_gp(ctxt, 0);
4176
4177 cr4 = ctxt->ops->get_cr(ctxt, 4);
4178 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
4179
4180 if ((new_val & X86_CR0_PG) && (efer & EFER_LME) &&
4181 !(cr4 & X86_CR4_PAE))
4182 return emulate_gp(ctxt, 0);
4183
4184 break;
4185 }
4186 case 3: {
4187 u64 rsvd = 0;
4188
4189 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
4190 if (efer & EFER_LMA) {
4191 u64 maxphyaddr;
4192 u32 eax, ebx, ecx, edx;
4193
4194 eax = 0x80000008;
4195 ecx = 0;
4196 if (ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx,
4197 &edx, false))
4198 maxphyaddr = eax & 0xff;
4199 else
4200 maxphyaddr = 36;
4201 rsvd = rsvd_bits(maxphyaddr, 63);
4202 if (ctxt->ops->get_cr(ctxt, 4) & X86_CR4_PCIDE)
4203 rsvd &= ~X86_CR3_PCID_NOFLUSH;
4204 }
4205
4206 if (new_val & rsvd)
4207 return emulate_gp(ctxt, 0);
4208
4209 break;
4210 }
4211 case 4: {
4212 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
4213
4214 if ((efer & EFER_LMA) && !(new_val & X86_CR4_PAE))
4215 return emulate_gp(ctxt, 0);
4216
4217 break;
4218 }
4219 }
4220
4221 return X86EMUL_CONTINUE;
4222 }
4223
4224 static int check_dr7_gd(struct x86_emulate_ctxt *ctxt)
4225 {
4226 unsigned long dr7;
4227
4228 ctxt->ops->get_dr(ctxt, 7, &dr7);
4229
4230 /* Check if DR7.Global_Enable is set */
4231 return dr7 & (1 << 13);
4232 }
4233
4234 static int check_dr_read(struct x86_emulate_ctxt *ctxt)
4235 {
4236 int dr = ctxt->modrm_reg;
4237 u64 cr4;
4238
4239 if (dr > 7)
4240 return emulate_ud(ctxt);
4241
4242 cr4 = ctxt->ops->get_cr(ctxt, 4);
4243 if ((cr4 & X86_CR4_DE) && (dr == 4 || dr == 5))
4244 return emulate_ud(ctxt);
4245
4246 if (check_dr7_gd(ctxt)) {
4247 ulong dr6;
4248
4249 ctxt->ops->get_dr(ctxt, 6, &dr6);
4250 dr6 &= ~15;
4251 dr6 |= DR6_BD | DR6_RTM;
4252 ctxt->ops->set_dr(ctxt, 6, dr6);
4253 return emulate_db(ctxt);
4254 }
4255
4256 return X86EMUL_CONTINUE;
4257 }
4258
4259 static int check_dr_write(struct x86_emulate_ctxt *ctxt)
4260 {
4261 u64 new_val = ctxt->src.val64;
4262 int dr = ctxt->modrm_reg;
4263
4264 if ((dr == 6 || dr == 7) && (new_val & 0xffffffff00000000ULL))
4265 return emulate_gp(ctxt, 0);
4266
4267 return check_dr_read(ctxt);
4268 }
4269
4270 static int check_svme(struct x86_emulate_ctxt *ctxt)
4271 {
4272 u64 efer = 0;
4273
4274 ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
4275
4276 if (!(efer & EFER_SVME))
4277 return emulate_ud(ctxt);
4278
4279 return X86EMUL_CONTINUE;
4280 }
4281
4282 static int check_svme_pa(struct x86_emulate_ctxt *ctxt)
4283 {
4284 u64 rax = reg_read(ctxt, VCPU_REGS_RAX);
4285
4286 /* Valid physical address? */
4287 if (rax & 0xffff000000000000ULL)
4288 return emulate_gp(ctxt, 0);
4289
4290 return check_svme(ctxt);
4291 }
4292
4293 static int check_rdtsc(struct x86_emulate_ctxt *ctxt)
4294 {
4295 u64 cr4 = ctxt->ops->get_cr(ctxt, 4);
4296
4297 if (cr4 & X86_CR4_TSD && ctxt->ops->cpl(ctxt))
4298 return emulate_ud(ctxt);
4299
4300 return X86EMUL_CONTINUE;
4301 }
4302
4303 static int check_rdpmc(struct x86_emulate_ctxt *ctxt)
4304 {
4305 u64 cr4 = ctxt->ops->get_cr(ctxt, 4);
4306 u64 rcx = reg_read(ctxt, VCPU_REGS_RCX);
4307
4308 /*
4309 * VMware allows access to these Pseduo-PMCs even when read via RDPMC
4310 * in Ring3 when CR4.PCE=0.
4311 */
4312 if (enable_vmware_backdoor && is_vmware_backdoor_pmc(rcx))
4313 return X86EMUL_CONTINUE;
4314
4315 if ((!(cr4 & X86_CR4_PCE) && ctxt->ops->cpl(ctxt)) ||
4316 ctxt->ops->check_pmc(ctxt, rcx))
4317 return emulate_gp(ctxt, 0);
4318
4319 return X86EMUL_CONTINUE;
4320 }
4321
4322 static int check_perm_in(struct x86_emulate_ctxt *ctxt)
4323 {
4324 ctxt->dst.bytes = min(ctxt->dst.bytes, 4u);
4325 if (!emulator_io_permited(ctxt, ctxt->src.val, ctxt->dst.bytes))
4326 return emulate_gp(ctxt, 0);
4327
4328 return X86EMUL_CONTINUE;
4329 }
4330
4331 static int check_perm_out(struct x86_emulate_ctxt *ctxt)
4332 {
4333 ctxt->src.bytes = min(ctxt->src.bytes, 4u);
4334 if (!emulator_io_permited(ctxt, ctxt->dst.val, ctxt->src.bytes))
4335 return emulate_gp(ctxt, 0);
4336
4337 return X86EMUL_CONTINUE;
4338 }
4339
4340 #define D(_y) { .flags = (_y) }
4341 #define DI(_y, _i) { .flags = (_y)|Intercept, .intercept = x86_intercept_##_i }
4342 #define DIP(_y, _i, _p) { .flags = (_y)|Intercept|CheckPerm, \
4343 .intercept = x86_intercept_##_i, .check_perm = (_p) }
4344 #define N D(NotImpl)
4345 #define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) }
4346 #define G(_f, _g) { .flags = ((_f) | Group | ModRM), .u.group = (_g) }
4347 #define GD(_f, _g) { .flags = ((_f) | GroupDual | ModRM), .u.gdual = (_g) }
4348 #define ID(_f, _i) { .flags = ((_f) | InstrDual | ModRM), .u.idual = (_i) }
4349 #define MD(_f, _m) { .flags = ((_f) | ModeDual), .u.mdual = (_m) }
4350 #define E(_f, _e) { .flags = ((_f) | Escape | ModRM), .u.esc = (_e) }
4351 #define I(_f, _e) { .flags = (_f), .u.execute = (_e) }
4352 #define F(_f, _e) { .flags = (_f) | Fastop, .u.fastop = (_e) }
4353 #define II(_f, _e, _i) \
4354 { .flags = (_f)|Intercept, .u.execute = (_e), .intercept = x86_intercept_##_i }
4355 #define IIP(_f, _e, _i, _p) \
4356 { .flags = (_f)|Intercept|CheckPerm, .u.execute = (_e), \
4357 .intercept = x86_intercept_##_i, .check_perm = (_p) }
4358 #define GP(_f, _g) { .flags = ((_f) | Prefix), .u.gprefix = (_g) }
4359
4360 #define D2bv(_f) D((_f) | ByteOp), D(_f)
4361 #define D2bvIP(_f, _i, _p) DIP((_f) | ByteOp, _i, _p), DIP(_f, _i, _p)
4362 #define I2bv(_f, _e) I((_f) | ByteOp, _e), I(_f, _e)
4363 #define F2bv(_f, _e) F((_f) | ByteOp, _e), F(_f, _e)
4364 #define I2bvIP(_f, _e, _i, _p) \
4365 IIP((_f) | ByteOp, _e, _i, _p), IIP(_f, _e, _i, _p)
4366
4367 #define F6ALU(_f, _e) F2bv((_f) | DstMem | SrcReg | ModRM, _e), \
4368 F2bv(((_f) | DstReg | SrcMem | ModRM) & ~Lock, _e), \
4369 F2bv(((_f) & ~Lock) | DstAcc | SrcImm, _e)
4370
4371 static const struct opcode group7_rm0[] = {
4372 N,
4373 I(SrcNone | Priv | EmulateOnUD, em_hypercall),
4374 N, N, N, N, N, N,
4375 };
4376
4377 static const struct opcode group7_rm1[] = {
4378 DI(SrcNone | Priv, monitor),
4379 DI(SrcNone | Priv, mwait),
4380 N, N, N, N, N, N,
4381 };
4382
4383 static const struct opcode group7_rm3[] = {
4384 DIP(SrcNone | Prot | Priv, vmrun, check_svme_pa),
4385 II(SrcNone | Prot | EmulateOnUD, em_hypercall, vmmcall),
4386 DIP(SrcNone | Prot | Priv, vmload, check_svme_pa),
4387 DIP(SrcNone | Prot | Priv, vmsave, check_svme_pa),
4388 DIP(SrcNone | Prot | Priv, stgi, check_svme),
4389 DIP(SrcNone | Prot | Priv, clgi, check_svme),
4390 DIP(SrcNone | Prot | Priv, skinit, check_svme),
4391 DIP(SrcNone | Prot | Priv, invlpga, check_svme),
4392 };
4393
4394 static const struct opcode group7_rm7[] = {
4395 N,
4396 DIP(SrcNone, rdtscp, check_rdtsc),
4397 N, N, N, N, N, N,
4398 };
4399
4400 static const struct opcode group1[] = {
4401 F(Lock, em_add),
4402 F(Lock | PageTable, em_or),
4403 F(Lock, em_adc),
4404 F(Lock, em_sbb),
4405 F(Lock | PageTable, em_and),
4406 F(Lock, em_sub),
4407 F(Lock, em_xor),
4408 F(NoWrite, em_cmp),
4409 };
4410
4411 static const struct opcode group1A[] = {
4412 I(DstMem | SrcNone | Mov | Stack | IncSP | TwoMemOp, em_pop), N, N, N, N, N, N, N,
4413 };
4414
4415 static const struct opcode group2[] = {
4416 F(DstMem | ModRM, em_rol),
4417 F(DstMem | ModRM, em_ror),
4418 F(DstMem | ModRM, em_rcl),
4419 F(DstMem | ModRM, em_rcr),
4420 F(DstMem | ModRM, em_shl),
4421 F(DstMem | ModRM, em_shr),
4422 F(DstMem | ModRM, em_shl),
4423 F(DstMem | ModRM, em_sar),
4424 };
4425
4426 static const struct opcode group3[] = {
4427 F(DstMem | SrcImm | NoWrite, em_test),
4428 F(DstMem | SrcImm | NoWrite, em_test),
4429 F(DstMem | SrcNone | Lock, em_not),
4430 F(DstMem | SrcNone | Lock, em_neg),
4431 F(DstXacc | Src2Mem, em_mul_ex),
4432 F(DstXacc | Src2Mem, em_imul_ex),
4433 F(DstXacc | Src2Mem, em_div_ex),
4434 F(DstXacc | Src2Mem, em_idiv_ex),
4435 };
4436
4437 static const struct opcode group4[] = {
4438 F(ByteOp | DstMem | SrcNone | Lock, em_inc),
4439 F(ByteOp | DstMem | SrcNone | Lock, em_dec),
4440 N, N, N, N, N, N,
4441 };
4442
4443 static const struct opcode group5[] = {
4444 F(DstMem | SrcNone | Lock, em_inc),
4445 F(DstMem | SrcNone | Lock, em_dec),
4446 I(SrcMem | NearBranch, em_call_near_abs),
4447 I(SrcMemFAddr | ImplicitOps, em_call_far),
4448 I(SrcMem | NearBranch, em_jmp_abs),
4449 I(SrcMemFAddr | ImplicitOps, em_jmp_far),
4450 I(SrcMem | Stack | TwoMemOp, em_push), D(Undefined),
4451 };
4452
4453 static const struct opcode group6[] = {
4454 II(Prot | DstMem, em_sldt, sldt),
4455 II(Prot | DstMem, em_str, str),
4456 II(Prot | Priv | SrcMem16, em_lldt, lldt),
4457 II(Prot | Priv | SrcMem16, em_ltr, ltr),
4458 N, N, N, N,
4459 };
4460
4461 static const struct group_dual group7 = { {
4462 II(Mov | DstMem, em_sgdt, sgdt),
4463 II(Mov | DstMem, em_sidt, sidt),
4464 II(SrcMem | Priv, em_lgdt, lgdt),
4465 II(SrcMem | Priv, em_lidt, lidt),
4466 II(SrcNone | DstMem | Mov, em_smsw, smsw), N,
4467 II(SrcMem16 | Mov | Priv, em_lmsw, lmsw),
4468 II(SrcMem | ByteOp | Priv | NoAccess, em_invlpg, invlpg),
4469 }, {
4470 EXT(0, group7_rm0),
4471 EXT(0, group7_rm1),
4472 N, EXT(0, group7_rm3),
4473 II(SrcNone | DstMem | Mov, em_smsw, smsw), N,
4474 II(SrcMem16 | Mov | Priv, em_lmsw, lmsw),
4475 EXT(0, group7_rm7),
4476 } };
4477
4478 static const struct opcode group8[] = {
4479 N, N, N, N,
4480 F(DstMem | SrcImmByte | NoWrite, em_bt),
4481 F(DstMem | SrcImmByte | Lock | PageTable, em_bts),
4482 F(DstMem | SrcImmByte | Lock, em_btr),
4483 F(DstMem | SrcImmByte | Lock | PageTable, em_btc),
4484 };
4485
4486 /*
4487 * The "memory" destination is actually always a register, since we come
4488 * from the register case of group9.
4489 */
4490 static const struct gprefix pfx_0f_c7_7 = {
4491 N, N, N, II(DstMem | ModRM | Op3264 | EmulateOnUD, em_rdpid, rdtscp),
4492 };
4493
4494
4495 static const struct group_dual group9 = { {
4496 N, I(DstMem64 | Lock | PageTable, em_cmpxchg8b), N, N, N, N, N, N,
4497 }, {
4498 N, N, N, N, N, N, N,
4499 GP(0, &pfx_0f_c7_7),
4500 } };
4501
4502 static const struct opcode group11[] = {
4503 I(DstMem | SrcImm | Mov | PageTable, em_mov),
4504 X7(D(Undefined)),
4505 };
4506
4507 static const struct gprefix pfx_0f_ae_7 = {
4508 I(SrcMem | ByteOp, em_clflush), N, N, N,
4509 };
4510
4511 static const struct group_dual group15 = { {
4512 I(ModRM | Aligned16, em_fxsave),
4513 I(ModRM | Aligned16, em_fxrstor),
4514 N, N, N, N, N, GP(0, &pfx_0f_ae_7),
4515 }, {
4516 N, N, N, N, N, N, N, N,
4517 } };
4518
4519 static const struct gprefix pfx_0f_6f_0f_7f = {
4520 I(Mmx, em_mov), I(Sse | Aligned, em_mov), N, I(Sse | Unaligned, em_mov),
4521 };
4522
4523 static const struct instr_dual instr_dual_0f_2b = {
4524 I(0, em_mov), N
4525 };
4526
4527 static const struct gprefix pfx_0f_2b = {
4528 ID(0, &instr_dual_0f_2b), ID(0, &instr_dual_0f_2b), N, N,
4529 };
4530
4531 static const struct gprefix pfx_0f_10_0f_11 = {
4532 I(Unaligned, em_mov), I(Unaligned, em_mov), N, N,
4533 };
4534
4535 static const struct gprefix pfx_0f_28_0f_29 = {
4536 I(Aligned, em_mov), I(Aligned, em_mov), N, N,
4537 };
4538
4539 static const struct gprefix pfx_0f_e7 = {
4540 N, I(Sse, em_mov), N, N,
4541 };
4542
4543 static const struct escape escape_d9 = { {
4544 N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstcw),
4545 }, {
4546 /* 0xC0 - 0xC7 */
4547 N, N, N, N, N, N, N, N,
4548 /* 0xC8 - 0xCF */
4549 N, N, N, N, N, N, N, N,
4550 /* 0xD0 - 0xC7 */
4551 N, N, N, N, N, N, N, N,
4552 /* 0xD8 - 0xDF */
4553 N, N, N, N, N, N, N, N,
4554 /* 0xE0 - 0xE7 */
4555 N, N, N, N, N, N, N, N,
4556 /* 0xE8 - 0xEF */
4557 N, N, N, N, N, N, N, N,
4558 /* 0xF0 - 0xF7 */
4559 N, N, N, N, N, N, N, N,
4560 /* 0xF8 - 0xFF */
4561 N, N, N, N, N, N, N, N,
4562 } };
4563
4564 static const struct escape escape_db = { {
4565 N, N, N, N, N, N, N, N,
4566 }, {
4567 /* 0xC0 - 0xC7 */
4568 N, N, N, N, N, N, N, N,
4569 /* 0xC8 - 0xCF */
4570 N, N, N, N, N, N, N, N,
4571 /* 0xD0 - 0xC7 */
4572 N, N, N, N, N, N, N, N,
4573 /* 0xD8 - 0xDF */
4574 N, N, N, N, N, N, N, N,
4575 /* 0xE0 - 0xE7 */
4576 N, N, N, I(ImplicitOps, em_fninit), N, N, N, N,
4577 /* 0xE8 - 0xEF */
4578 N, N, N, N, N, N, N, N,
4579 /* 0xF0 - 0xF7 */
4580 N, N, N, N, N, N, N, N,
4581 /* 0xF8 - 0xFF */
4582 N, N, N, N, N, N, N, N,
4583 } };
4584
4585 static const struct escape escape_dd = { {
4586 N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstsw),
4587 }, {
4588 /* 0xC0 - 0xC7 */
4589 N, N, N, N, N, N, N, N,
4590 /* 0xC8 - 0xCF */
4591 N, N, N, N, N, N, N, N,
4592 /* 0xD0 - 0xC7 */
4593 N, N, N, N, N, N, N, N,
4594 /* 0xD8 - 0xDF */
4595 N, N, N, N, N, N, N, N,
4596 /* 0xE0 - 0xE7 */
4597 N, N, N, N, N, N, N, N,
4598 /* 0xE8 - 0xEF */
4599 N, N, N, N, N, N, N, N,
4600 /* 0xF0 - 0xF7 */
4601 N, N, N, N, N, N, N, N,
4602 /* 0xF8 - 0xFF */
4603 N, N, N, N, N, N, N, N,
4604 } };
4605
4606 static const struct instr_dual instr_dual_0f_c3 = {
4607 I(DstMem | SrcReg | ModRM | No16 | Mov, em_mov), N
4608 };
4609
4610 static const struct mode_dual mode_dual_63 = {
4611 N, I(DstReg | SrcMem32 | ModRM | Mov, em_movsxd)
4612 };
4613
4614 static const struct opcode opcode_table[256] = {
4615 /* 0x00 - 0x07 */
4616 F6ALU(Lock, em_add),
4617 I(ImplicitOps | Stack | No64 | Src2ES, em_push_sreg),
4618 I(ImplicitOps | Stack | No64 | Src2ES, em_pop_sreg),
4619 /* 0x08 - 0x0F */
4620 F6ALU(Lock | PageTable, em_or),
4621 I(ImplicitOps | Stack | No64 | Src2CS, em_push_sreg),
4622 N,
4623 /* 0x10 - 0x17 */
4624 F6ALU(Lock, em_adc),
4625 I(ImplicitOps | Stack | No64 | Src2SS, em_push_sreg),
4626 I(ImplicitOps | Stack | No64 | Src2SS, em_pop_sreg),
4627 /* 0x18 - 0x1F */
4628 F6ALU(Lock, em_sbb),
4629 I(ImplicitOps | Stack | No64 | Src2DS, em_push_sreg),
4630 I(ImplicitOps | Stack | No64 | Src2DS, em_pop_sreg),
4631 /* 0x20 - 0x27 */
4632 F6ALU(Lock | PageTable, em_and), N, N,
4633 /* 0x28 - 0x2F */
4634 F6ALU(Lock, em_sub), N, I(ByteOp | DstAcc | No64, em_das),
4635 /* 0x30 - 0x37 */
4636 F6ALU(Lock, em_xor), N, N,
4637 /* 0x38 - 0x3F */
4638 F6ALU(NoWrite, em_cmp), N, N,
4639 /* 0x40 - 0x4F */
4640 X8(F(DstReg, em_inc)), X8(F(DstReg, em_dec)),
4641 /* 0x50 - 0x57 */
4642 X8(I(SrcReg | Stack, em_push)),
4643 /* 0x58 - 0x5F */
4644 X8(I(DstReg | Stack, em_pop)),
4645 /* 0x60 - 0x67 */
4646 I(ImplicitOps | Stack | No64, em_pusha),
4647 I(ImplicitOps | Stack | No64, em_popa),
4648 N, MD(ModRM, &mode_dual_63),
4649 N, N, N, N,
4650 /* 0x68 - 0x6F */
4651 I(SrcImm | Mov | Stack, em_push),
4652 I(DstReg | SrcMem | ModRM | Src2Imm, em_imul_3op),
4653 I(SrcImmByte | Mov | Stack, em_push),
4654 I(DstReg | SrcMem | ModRM | Src2ImmByte, em_imul_3op),
4655 I2bvIP(DstDI | SrcDX | Mov | String | Unaligned, em_in, ins, check_perm_in), /* insb, insw/insd */
4656 I2bvIP(SrcSI | DstDX | String, em_out, outs, check_perm_out), /* outsb, outsw/outsd */
4657 /* 0x70 - 0x7F */
4658 X16(D(SrcImmByte | NearBranch)),
4659 /* 0x80 - 0x87 */
4660 G(ByteOp | DstMem | SrcImm, group1),
4661 G(DstMem | SrcImm, group1),
4662 G(ByteOp | DstMem | SrcImm | No64, group1),
4663 G(DstMem | SrcImmByte, group1),
4664 F2bv(DstMem | SrcReg | ModRM | NoWrite, em_test),
4665 I2bv(DstMem | SrcReg | ModRM | Lock | PageTable, em_xchg),
4666 /* 0x88 - 0x8F */
4667 I2bv(DstMem | SrcReg | ModRM | Mov | PageTable, em_mov),
4668 I2bv(DstReg | SrcMem | ModRM | Mov, em_mov),
4669 I(DstMem | SrcNone | ModRM | Mov | PageTable, em_mov_rm_sreg),
4670 D(ModRM | SrcMem | NoAccess | DstReg),
4671 I(ImplicitOps | SrcMem16 | ModRM, em_mov_sreg_rm),
4672 G(0, group1A),
4673 /* 0x90 - 0x97 */
4674 DI(SrcAcc | DstReg, pause), X7(D(SrcAcc | DstReg)),
4675 /* 0x98 - 0x9F */
4676 D(DstAcc | SrcNone), I(ImplicitOps | SrcAcc, em_cwd),
4677 I(SrcImmFAddr | No64, em_call_far), N,
4678 II(ImplicitOps | Stack, em_pushf, pushf),
4679 II(ImplicitOps | Stack, em_popf, popf),
4680 I(ImplicitOps, em_sahf), I(ImplicitOps, em_lahf),
4681 /* 0xA0 - 0xA7 */
4682 I2bv(DstAcc | SrcMem | Mov | MemAbs, em_mov),
4683 I2bv(DstMem | SrcAcc | Mov | MemAbs | PageTable, em_mov),
4684 I2bv(SrcSI | DstDI | Mov | String | TwoMemOp, em_mov),
4685 F2bv(SrcSI | DstDI | String | NoWrite | TwoMemOp, em_cmp_r),
4686 /* 0xA8 - 0xAF */
4687 F2bv(DstAcc | SrcImm | NoWrite, em_test),
4688 I2bv(SrcAcc | DstDI | Mov | String, em_mov),
4689 I2bv(SrcSI | DstAcc | Mov | String, em_mov),
4690 F2bv(SrcAcc | DstDI | String | NoWrite, em_cmp_r),
4691 /* 0xB0 - 0xB7 */
4692 X8(I(ByteOp | DstReg | SrcImm | Mov, em_mov)),
4693 /* 0xB8 - 0xBF */
4694 X8(I(DstReg | SrcImm64 | Mov, em_mov)),
4695 /* 0xC0 - 0xC7 */
4696 G(ByteOp | Src2ImmByte, group2), G(Src2ImmByte, group2),
4697 I(ImplicitOps | NearBranch | SrcImmU16, em_ret_near_imm),
4698 I(ImplicitOps | NearBranch, em_ret),
4699 I(DstReg | SrcMemFAddr | ModRM | No64 | Src2ES, em_lseg),
4700 I(DstReg | SrcMemFAddr | ModRM | No64 | Src2DS, em_lseg),
4701 G(ByteOp, group11), G(0, group11),
4702 /* 0xC8 - 0xCF */
4703 I(Stack | SrcImmU16 | Src2ImmByte, em_enter), I(Stack, em_leave),
4704 I(ImplicitOps | SrcImmU16, em_ret_far_imm),
4705 I(ImplicitOps, em_ret_far),
4706 D(ImplicitOps), DI(SrcImmByte, intn),
4707 D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret),
4708 /* 0xD0 - 0xD7 */
4709 G(Src2One | ByteOp, group2), G(Src2One, group2),
4710 G(Src2CL | ByteOp, group2), G(Src2CL, group2),
4711 I(DstAcc | SrcImmUByte | No64, em_aam),
4712 I(DstAcc | SrcImmUByte | No64, em_aad),
4713 F(DstAcc | ByteOp | No64, em_salc),
4714 I(DstAcc | SrcXLat | ByteOp, em_mov),
4715 /* 0xD8 - 0xDF */
4716 N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N,
4717 /* 0xE0 - 0xE7 */
4718 X3(I(SrcImmByte | NearBranch, em_loop)),
4719 I(SrcImmByte | NearBranch, em_jcxz),
4720 I2bvIP(SrcImmUByte | DstAcc, em_in, in, check_perm_in),
4721 I2bvIP(SrcAcc | DstImmUByte, em_out, out, check_perm_out),
4722 /* 0xE8 - 0xEF */
4723 I(SrcImm | NearBranch, em_call), D(SrcImm | ImplicitOps | NearBranch),
4724 I(SrcImmFAddr | No64, em_jmp_far),
4725 D(SrcImmByte | ImplicitOps | NearBranch),
4726 I2bvIP(SrcDX | DstAcc, em_in, in, check_perm_in),
4727 I2bvIP(SrcAcc | DstDX, em_out, out, check_perm_out),
4728 /* 0xF0 - 0xF7 */
4729 N, DI(ImplicitOps, icebp), N, N,
4730 DI(ImplicitOps | Priv, hlt), D(ImplicitOps),
4731 G(ByteOp, group3), G(0, group3),
4732 /* 0xF8 - 0xFF */
4733 D(ImplicitOps), D(ImplicitOps),
4734 I(ImplicitOps, em_cli), I(ImplicitOps, em_sti),
4735 D(ImplicitOps), D(ImplicitOps), G(0, group4), G(0, group5),
4736 };
4737
4738 static const struct opcode twobyte_table[256] = {
4739 /* 0x00 - 0x0F */
4740 G(0, group6), GD(0, &group7), N, N,
4741 N, I(ImplicitOps | EmulateOnUD, em_syscall),
4742 II(ImplicitOps | Priv, em_clts, clts), N,
4743 DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
4744 N, D(ImplicitOps | ModRM | SrcMem | NoAccess), N, N,
4745 /* 0x10 - 0x1F */
4746 GP(ModRM | DstReg | SrcMem | Mov | Sse, &pfx_0f_10_0f_11),
4747 GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_10_0f_11),
4748 N, N, N, N, N, N,
4749 D(ImplicitOps | ModRM | SrcMem | NoAccess),
4750 N, N, N, N, N, N, D(ImplicitOps | ModRM | SrcMem | NoAccess),
4751 /* 0x20 - 0x2F */
4752 DIP(ModRM | DstMem | Priv | Op3264 | NoMod, cr_read, check_cr_read),
4753 DIP(ModRM | DstMem | Priv | Op3264 | NoMod, dr_read, check_dr_read),
4754 IIP(ModRM | SrcMem | Priv | Op3264 | NoMod, em_cr_write, cr_write,
4755 check_cr_write),
4756 IIP(ModRM | SrcMem | Priv | Op3264 | NoMod, em_dr_write, dr_write,
4757 check_dr_write),
4758 N, N, N, N,
4759 GP(ModRM | DstReg | SrcMem | Mov | Sse, &pfx_0f_28_0f_29),
4760 GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_28_0f_29),
4761 N, GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_2b),
4762 N, N, N, N,
4763 /* 0x30 - 0x3F */
4764 II(ImplicitOps | Priv, em_wrmsr, wrmsr),
4765 IIP(ImplicitOps, em_rdtsc, rdtsc, check_rdtsc),
4766 II(ImplicitOps | Priv, em_rdmsr, rdmsr),
4767 IIP(ImplicitOps, em_rdpmc, rdpmc, check_rdpmc),
4768 I(ImplicitOps | EmulateOnUD, em_sysenter),
4769 I(ImplicitOps | Priv | EmulateOnUD, em_sysexit),
4770 N, N,
4771 N, N, N, N, N, N, N, N,
4772 /* 0x40 - 0x4F */
4773 X16(D(DstReg | SrcMem | ModRM)),
4774 /* 0x50 - 0x5F */
4775 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N,
4776 /* 0x60 - 0x6F */
4777 N, N, N, N,
4778 N, N, N, N,
4779 N, N, N, N,
4780 N, N, N, GP(SrcMem | DstReg | ModRM | Mov, &pfx_0f_6f_0f_7f),
4781 /* 0x70 - 0x7F */
4782 N, N, N, N,
4783 N, N, N, N,
4784 N, N, N, N,
4785 N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_6f_0f_7f),
4786 /* 0x80 - 0x8F */
4787 X16(D(SrcImm | NearBranch)),
4788 /* 0x90 - 0x9F */
4789 X16(D(ByteOp | DstMem | SrcNone | ModRM| Mov)),
4790 /* 0xA0 - 0xA7 */
4791 I(Stack | Src2FS, em_push_sreg), I(Stack | Src2FS, em_pop_sreg),
4792 II(ImplicitOps, em_cpuid, cpuid),
4793 F(DstMem | SrcReg | ModRM | BitOp | NoWrite, em_bt),
4794 F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shld),
4795 F(DstMem | SrcReg | Src2CL | ModRM, em_shld), N, N,
4796 /* 0xA8 - 0xAF */
4797 I(Stack | Src2GS, em_push_sreg), I(Stack | Src2GS, em_pop_sreg),
4798 II(EmulateOnUD | ImplicitOps, em_rsm, rsm),
4799 F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_bts),
4800 F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shrd),
4801 F(DstMem | SrcReg | Src2CL | ModRM, em_shrd),
4802 GD(0, &group15), F(DstReg | SrcMem | ModRM, em_imul),
4803 /* 0xB0 - 0xB7 */
4804 I2bv(DstMem | SrcReg | ModRM | Lock | PageTable | SrcWrite, em_cmpxchg),
4805 I(DstReg | SrcMemFAddr | ModRM | Src2SS, em_lseg),
4806 F(DstMem | SrcReg | ModRM | BitOp | Lock, em_btr),
4807 I(DstReg | SrcMemFAddr | ModRM | Src2FS, em_lseg),
4808 I(DstReg | SrcMemFAddr | ModRM | Src2GS, em_lseg),
4809 D(DstReg | SrcMem8 | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
4810 /* 0xB8 - 0xBF */
4811 N, N,
4812 G(BitOp, group8),
4813 F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_btc),
4814 I(DstReg | SrcMem | ModRM, em_bsf_c),
4815 I(DstReg | SrcMem | ModRM, em_bsr_c),
4816 D(DstReg | SrcMem8 | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
4817 /* 0xC0 - 0xC7 */
4818 F2bv(DstMem | SrcReg | ModRM | SrcWrite | Lock, em_xadd),
4819 N, ID(0, &instr_dual_0f_c3),
4820 N, N, N, GD(0, &group9),
4821 /* 0xC8 - 0xCF */
4822 X8(I(DstReg, em_bswap)),
4823 /* 0xD0 - 0xDF */
4824 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N,
4825 /* 0xE0 - 0xEF */
4826 N, N, N, N, N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_e7),
4827 N, N, N, N, N, N, N, N,
4828 /* 0xF0 - 0xFF */
4829 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N
4830 };
4831
4832 static const struct instr_dual instr_dual_0f_38_f0 = {
4833 I(DstReg | SrcMem | Mov, em_movbe), N
4834 };
4835
4836 static const struct instr_dual instr_dual_0f_38_f1 = {
4837 I(DstMem | SrcReg | Mov, em_movbe), N
4838 };
4839
4840 static const struct gprefix three_byte_0f_38_f0 = {
4841 ID(0, &instr_dual_0f_38_f0), N, N, N
4842 };
4843
4844 static const struct gprefix three_byte_0f_38_f1 = {
4845 ID(0, &instr_dual_0f_38_f1), N, N, N
4846 };
4847
4848 /*
4849 * Insns below are selected by the prefix which indexed by the third opcode
4850 * byte.
4851 */
4852 static const struct opcode opcode_map_0f_38[256] = {
4853 /* 0x00 - 0x7f */
4854 X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N),
4855 /* 0x80 - 0xef */
4856 X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N),
4857 /* 0xf0 - 0xf1 */
4858 GP(EmulateOnUD | ModRM, &three_byte_0f_38_f0),
4859 GP(EmulateOnUD | ModRM, &three_byte_0f_38_f1),
4860 /* 0xf2 - 0xff */
4861 N, N, X4(N), X8(N)
4862 };
4863
4864 #undef D
4865 #undef N
4866 #undef G
4867 #undef GD
4868 #undef I
4869 #undef GP
4870 #undef EXT
4871 #undef MD
4872 #undef ID
4873
4874 #undef D2bv
4875 #undef D2bvIP
4876 #undef I2bv
4877 #undef I2bvIP
4878 #undef I6ALU
4879
4880 static unsigned imm_size(struct x86_emulate_ctxt *ctxt)
4881 {
4882 unsigned size;
4883
4884 size = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
4885 if (size == 8)
4886 size = 4;
4887 return size;
4888 }
4889
4890 static int decode_imm(struct x86_emulate_ctxt *ctxt, struct operand *op,
4891 unsigned size, bool sign_extension)
4892 {
4893 int rc = X86EMUL_CONTINUE;
4894
4895 op->type = OP_IMM;
4896 op->bytes = size;
4897 op->addr.mem.ea = ctxt->_eip;
4898 /* NB. Immediates are sign-extended as necessary. */
4899 switch (op->bytes) {
4900 case 1:
4901 op->val = insn_fetch(s8, ctxt);
4902 break;
4903 case 2:
4904 op->val = insn_fetch(s16, ctxt);
4905 break;
4906 case 4:
4907 op->val = insn_fetch(s32, ctxt);
4908 break;
4909 case 8:
4910 op->val = insn_fetch(s64, ctxt);
4911 break;
4912 }
4913 if (!sign_extension) {
4914 switch (op->bytes) {
4915 case 1:
4916 op->val &= 0xff;
4917 break;
4918 case 2:
4919 op->val &= 0xffff;
4920 break;
4921 case 4:
4922 op->val &= 0xffffffff;
4923 break;
4924 }
4925 }
4926 done:
4927 return rc;
4928 }
4929
4930 static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op,
4931 unsigned d)
4932 {
4933 int rc = X86EMUL_CONTINUE;
4934
4935 switch (d) {
4936 case OpReg:
4937 decode_register_operand(ctxt, op);
4938 break;
4939 case OpImmUByte:
4940 rc = decode_imm(ctxt, op, 1, false);
4941 break;
4942 case OpMem:
4943 ctxt->memop.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
4944 mem_common:
4945 *op = ctxt->memop;
4946 ctxt->memopp = op;
4947 if (ctxt->d & BitOp)
4948 fetch_bit_operand(ctxt);
4949 op->orig_val = op->val;
4950 break;
4951 case OpMem64:
4952 ctxt->memop.bytes = (ctxt->op_bytes == 8) ? 16 : 8;
4953 goto mem_common;
4954 case OpAcc:
4955 op->type = OP_REG;
4956 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
4957 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX);
4958 fetch_register_operand(op);
4959 op->orig_val = op->val;
4960 break;
4961 case OpAccLo:
4962 op->type = OP_REG;
4963 op->bytes = (ctxt->d & ByteOp) ? 2 : ctxt->op_bytes;
4964 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX);
4965 fetch_register_operand(op);
4966 op->orig_val = op->val;
4967 break;
4968 case OpAccHi:
4969 if (ctxt->d & ByteOp) {
4970 op->type = OP_NONE;
4971 break;
4972 }
4973 op->type = OP_REG;
4974 op->bytes = ctxt->op_bytes;
4975 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX);
4976 fetch_register_operand(op);
4977 op->orig_val = op->val;
4978 break;
4979 case OpDI:
4980 op->type = OP_MEM;
4981 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
4982 op->addr.mem.ea =
4983 register_address(ctxt, VCPU_REGS_RDI);
4984 op->addr.mem.seg = VCPU_SREG_ES;
4985 op->val = 0;
4986 op->count = 1;
4987 break;
4988 case OpDX:
4989 op->type = OP_REG;
4990 op->bytes = 2;
4991 op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX);
4992 fetch_register_operand(op);
4993 break;
4994 case OpCL:
4995 op->type = OP_IMM;
4996 op->bytes = 1;
4997 op->val = reg_read(ctxt, VCPU_REGS_RCX) & 0xff;
4998 break;
4999 case OpImmByte:
5000 rc = decode_imm(ctxt, op, 1, true);
5001 break;
5002 case OpOne:
5003 op->type = OP_IMM;
5004 op->bytes = 1;
5005 op->val = 1;
5006 break;
5007 case OpImm:
5008 rc = decode_imm(ctxt, op, imm_size(ctxt), true);
5009 break;
5010 case OpImm64:
5011 rc = decode_imm(ctxt, op, ctxt->op_bytes, true);
5012 break;
5013 case OpMem8:
5014 ctxt->memop.bytes = 1;
5015 if (ctxt->memop.type == OP_REG) {
5016 ctxt->memop.addr.reg = decode_register(ctxt,
5017 ctxt->modrm_rm, true);
5018 fetch_register_operand(&ctxt->memop);
5019 }
5020 goto mem_common;
5021 case OpMem16:
5022 ctxt->memop.bytes = 2;
5023 goto mem_common;
5024 case OpMem32:
5025 ctxt->memop.bytes = 4;
5026 goto mem_common;
5027 case OpImmU16:
5028 rc = decode_imm(ctxt, op, 2, false);
5029 break;
5030 case OpImmU:
5031 rc = decode_imm(ctxt, op, imm_size(ctxt), false);
5032 break;
5033 case OpSI:
5034 op->type = OP_MEM;
5035 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
5036 op->addr.mem.ea =
5037 register_address(ctxt, VCPU_REGS_RSI);
5038 op->addr.mem.seg = ctxt->seg_override;
5039 op->val = 0;
5040 op->count = 1;
5041 break;
5042 case OpXLat:
5043 op->type = OP_MEM;
5044 op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
5045 op->addr.mem.ea =
5046 address_mask(ctxt,
5047 reg_read(ctxt, VCPU_REGS_RBX) +
5048 (reg_read(ctxt, VCPU_REGS_RAX) & 0xff));
5049 op->addr.mem.seg = ctxt->seg_override;
5050 op->val = 0;
5051 break;
5052 case OpImmFAddr:
5053 op->type = OP_IMM;
5054 op->addr.mem.ea = ctxt->_eip;
5055 op->bytes = ctxt->op_bytes + 2;
5056 insn_fetch_arr(op->valptr, op->bytes, ctxt);
5057 break;
5058 case OpMemFAddr:
5059 ctxt->memop.bytes = ctxt->op_bytes + 2;
5060 goto mem_common;
5061 case OpES:
5062 op->type = OP_IMM;
5063 op->val = VCPU_SREG_ES;
5064 break;
5065 case OpCS:
5066 op->type = OP_IMM;
5067 op->val = VCPU_SREG_CS;
5068 break;
5069 case OpSS:
5070 op->type = OP_IMM;
5071 op->val = VCPU_SREG_SS;
5072 break;
5073 case OpDS:
5074 op->type = OP_IMM;
5075 op->val = VCPU_SREG_DS;
5076 break;
5077 case OpFS:
5078 op->type = OP_IMM;
5079 op->val = VCPU_SREG_FS;
5080 break;
5081 case OpGS:
5082 op->type = OP_IMM;
5083 op->val = VCPU_SREG_GS;
5084 break;
5085 case OpImplicit:
5086 /* Special instructions do their own operand decoding. */
5087 default:
5088 op->type = OP_NONE; /* Disable writeback. */
5089 break;
5090 }
5091
5092 done:
5093 return rc;
5094 }
5095
5096 int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
5097 {
5098 int rc = X86EMUL_CONTINUE;
5099 int mode = ctxt->mode;
5100 int def_op_bytes, def_ad_bytes, goffset, simd_prefix;
5101 bool op_prefix = false;
5102 bool has_seg_override = false;
5103 struct opcode opcode;
5104 u16 dummy;
5105 struct desc_struct desc;
5106
5107 ctxt->memop.type = OP_NONE;
5108 ctxt->memopp = NULL;
5109 ctxt->_eip = ctxt->eip;
5110 ctxt->fetch.ptr = ctxt->fetch.data;
5111 ctxt->fetch.end = ctxt->fetch.data + insn_len;
5112 ctxt->opcode_len = 1;
5113 if (insn_len > 0)
5114 memcpy(ctxt->fetch.data, insn, insn_len);
5115 else {
5116 rc = __do_insn_fetch_bytes(ctxt, 1);
5117 if (rc != X86EMUL_CONTINUE)
5118 return rc;
5119 }
5120
5121 switch (mode) {
5122 case X86EMUL_MODE_REAL:
5123 case X86EMUL_MODE_VM86:
5124 def_op_bytes = def_ad_bytes = 2;
5125 ctxt->ops->get_segment(ctxt, &dummy, &desc, NULL, VCPU_SREG_CS);
5126 if (desc.d)
5127 def_op_bytes = def_ad_bytes = 4;
5128 break;
5129 case X86EMUL_MODE_PROT16:
5130 def_op_bytes = def_ad_bytes = 2;
5131 break;
5132 case X86EMUL_MODE_PROT32:
5133 def_op_bytes = def_ad_bytes = 4;
5134 break;
5135 #ifdef CONFIG_X86_64
5136 case X86EMUL_MODE_PROT64:
5137 def_op_bytes = 4;
5138 def_ad_bytes = 8;
5139 break;
5140 #endif
5141 default:
5142 return EMULATION_FAILED;
5143 }
5144
5145 ctxt->op_bytes = def_op_bytes;
5146 ctxt->ad_bytes = def_ad_bytes;
5147
5148 /* Legacy prefixes. */
5149 for (;;) {
5150 switch (ctxt->b = insn_fetch(u8, ctxt)) {
5151 case 0x66: /* operand-size override */
5152 op_prefix = true;
5153 /* switch between 2/4 bytes */
5154 ctxt->op_bytes = def_op_bytes ^ 6;
5155 break;
5156 case 0x67: /* address-size override */
5157 if (mode == X86EMUL_MODE_PROT64)
5158 /* switch between 4/8 bytes */
5159 ctxt->ad_bytes = def_ad_bytes ^ 12;
5160 else
5161 /* switch between 2/4 bytes */
5162 ctxt->ad_bytes = def_ad_bytes ^ 6;
5163 break;
5164 case 0x26: /* ES override */
5165 case 0x2e: /* CS override */
5166 case 0x36: /* SS override */
5167 case 0x3e: /* DS override */
5168 has_seg_override = true;
5169 ctxt->seg_override = (ctxt->b >> 3) & 3;
5170 break;
5171 case 0x64: /* FS override */
5172 case 0x65: /* GS override */
5173 has_seg_override = true;
5174 ctxt->seg_override = ctxt->b & 7;
5175 break;
5176 case 0x40 ... 0x4f: /* REX */
5177 if (mode != X86EMUL_MODE_PROT64)
5178 goto done_prefixes;
5179 ctxt->rex_prefix = ctxt->b;
5180 continue;
5181 case 0xf0: /* LOCK */
5182 ctxt->lock_prefix = 1;
5183 break;
5184 case 0xf2: /* REPNE/REPNZ */
5185 case 0xf3: /* REP/REPE/REPZ */
5186 ctxt->rep_prefix = ctxt->b;
5187 break;
5188 default:
5189 goto done_prefixes;
5190 }
5191
5192 /* Any legacy prefix after a REX prefix nullifies its effect. */
5193
5194 ctxt->rex_prefix = 0;
5195 }
5196
5197 done_prefixes:
5198
5199 /* REX prefix. */
5200 if (ctxt->rex_prefix & 8)
5201 ctxt->op_bytes = 8; /* REX.W */
5202
5203 /* Opcode byte(s). */
5204 opcode = opcode_table[ctxt->b];
5205 /* Two-byte opcode? */
5206 if (ctxt->b == 0x0f) {
5207 ctxt->opcode_len = 2;
5208 ctxt->b = insn_fetch(u8, ctxt);
5209 opcode = twobyte_table[ctxt->b];
5210
5211 /* 0F_38 opcode map */
5212 if (ctxt->b == 0x38) {
5213 ctxt->opcode_len = 3;
5214 ctxt->b = insn_fetch(u8, ctxt);
5215 opcode = opcode_map_0f_38[ctxt->b];
5216 }
5217 }
5218 ctxt->d = opcode.flags;
5219
5220 if (ctxt->d & ModRM)
5221 ctxt->modrm = insn_fetch(u8, ctxt);
5222
5223 /* vex-prefix instructions are not implemented */
5224 if (ctxt->opcode_len == 1 && (ctxt->b == 0xc5 || ctxt->b == 0xc4) &&
5225 (mode == X86EMUL_MODE_PROT64 || (ctxt->modrm & 0xc0) == 0xc0)) {
5226 ctxt->d = NotImpl;
5227 }
5228
5229 while (ctxt->d & GroupMask) {
5230 switch (ctxt->d & GroupMask) {
5231 case Group:
5232 goffset = (ctxt->modrm >> 3) & 7;
5233 opcode = opcode.u.group[goffset];
5234 break;
5235 case GroupDual:
5236 goffset = (ctxt->modrm >> 3) & 7;
5237 if ((ctxt->modrm >> 6) == 3)
5238 opcode = opcode.u.gdual->mod3[goffset];
5239 else
5240 opcode = opcode.u.gdual->mod012[goffset];
5241 break;
5242 case RMExt:
5243 goffset = ctxt->modrm & 7;
5244 opcode = opcode.u.group[goffset];
5245 break;
5246 case Prefix:
5247 if (ctxt->rep_prefix && op_prefix)
5248 return EMULATION_FAILED;
5249 simd_prefix = op_prefix ? 0x66 : ctxt->rep_prefix;
5250 switch (simd_prefix) {
5251 case 0x00: opcode = opcode.u.gprefix->pfx_no; break;
5252 case 0x66: opcode = opcode.u.gprefix->pfx_66; break;
5253 case 0xf2: opcode = opcode.u.gprefix->pfx_f2; break;
5254 case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break;
5255 }
5256 break;
5257 case Escape:
5258 if (ctxt->modrm > 0xbf)
5259 opcode = opcode.u.esc->high[ctxt->modrm - 0xc0];
5260 else
5261 opcode = opcode.u.esc->op[(ctxt->modrm >> 3) & 7];
5262 break;
5263 case InstrDual:
5264 if ((ctxt->modrm >> 6) == 3)
5265 opcode = opcode.u.idual->mod3;
5266 else
5267 opcode = opcode.u.idual->mod012;
5268 break;
5269 case ModeDual:
5270 if (ctxt->mode == X86EMUL_MODE_PROT64)
5271 opcode = opcode.u.mdual->mode64;
5272 else
5273 opcode = opcode.u.mdual->mode32;
5274 break;
5275 default:
5276 return EMULATION_FAILED;
5277 }
5278
5279 ctxt->d &= ~(u64)GroupMask;
5280 ctxt->d |= opcode.flags;
5281 }
5282
5283 /* Unrecognised? */
5284 if (ctxt->d == 0)
5285 return EMULATION_FAILED;
5286
5287 ctxt->execute = opcode.u.execute;
5288
5289 if (unlikely(ctxt->ud) && likely(!(ctxt->d & EmulateOnUD)))
5290 return EMULATION_FAILED;
5291
5292 if (unlikely(ctxt->d &
5293 (NotImpl|Stack|Op3264|Sse|Mmx|Intercept|CheckPerm|NearBranch|
5294 No16))) {
5295 /*
5296 * These are copied unconditionally here, and checked unconditionally
5297 * in x86_emulate_insn.
5298 */
5299 ctxt->check_perm = opcode.check_perm;
5300 ctxt->intercept = opcode.intercept;
5301
5302 if (ctxt->d & NotImpl)
5303 return EMULATION_FAILED;
5304
5305 if (mode == X86EMUL_MODE_PROT64) {
5306 if (ctxt->op_bytes == 4 && (ctxt->d & Stack))
5307 ctxt->op_bytes = 8;
5308 else if (ctxt->d & NearBranch)
5309 ctxt->op_bytes = 8;
5310 }
5311
5312 if (ctxt->d & Op3264) {
5313 if (mode == X86EMUL_MODE_PROT64)
5314 ctxt->op_bytes = 8;
5315 else
5316 ctxt->op_bytes = 4;
5317 }
5318
5319 if ((ctxt->d & No16) && ctxt->op_bytes == 2)
5320 ctxt->op_bytes = 4;
5321
5322 if (ctxt->d & Sse)
5323 ctxt->op_bytes = 16;
5324 else if (ctxt->d & Mmx)
5325 ctxt->op_bytes = 8;
5326 }
5327
5328 /* ModRM and SIB bytes. */
5329 if (ctxt->d & ModRM) {
5330 rc = decode_modrm(ctxt, &ctxt->memop);
5331 if (!has_seg_override) {
5332 has_seg_override = true;
5333 ctxt->seg_override = ctxt->modrm_seg;
5334 }
5335 } else if (ctxt->d & MemAbs)
5336 rc = decode_abs(ctxt, &ctxt->memop);
5337 if (rc != X86EMUL_CONTINUE)
5338 goto done;
5339
5340 if (!has_seg_override)
5341 ctxt->seg_override = VCPU_SREG_DS;
5342
5343 ctxt->memop.addr.mem.seg = ctxt->seg_override;
5344
5345 /*
5346 * Decode and fetch the source operand: register, memory
5347 * or immediate.
5348 */
5349 rc = decode_operand(ctxt, &ctxt->src, (ctxt->d >> SrcShift) & OpMask);
5350 if (rc != X86EMUL_CONTINUE)
5351 goto done;
5352
5353 /*
5354 * Decode and fetch the second source operand: register, memory
5355 * or immediate.
5356 */
5357 rc = decode_operand(ctxt, &ctxt->src2, (ctxt->d >> Src2Shift) & OpMask);
5358 if (rc != X86EMUL_CONTINUE)
5359 goto done;
5360
5361 /* Decode and fetch the destination operand: register or memory. */
5362 rc = decode_operand(ctxt, &ctxt->dst, (ctxt->d >> DstShift) & OpMask);
5363
5364 if (ctxt->rip_relative && likely(ctxt->memopp))
5365 ctxt->memopp->addr.mem.ea = address_mask(ctxt,
5366 ctxt->memopp->addr.mem.ea + ctxt->_eip);
5367
5368 done:
5369 return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK;
5370 }
5371
5372 bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt)
5373 {
5374 return ctxt->d & PageTable;
5375 }
5376
5377 static bool string_insn_completed(struct x86_emulate_ctxt *ctxt)
5378 {
5379 /* The second termination condition only applies for REPE
5380 * and REPNE. Test if the repeat string operation prefix is
5381 * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the
5382 * corresponding termination condition according to:
5383 * - if REPE/REPZ and ZF = 0 then done
5384 * - if REPNE/REPNZ and ZF = 1 then done
5385 */
5386 if (((ctxt->b == 0xa6) || (ctxt->b == 0xa7) ||
5387 (ctxt->b == 0xae) || (ctxt->b == 0xaf))
5388 && (((ctxt->rep_prefix == REPE_PREFIX) &&
5389 ((ctxt->eflags & X86_EFLAGS_ZF) == 0))
5390 || ((ctxt->rep_prefix == REPNE_PREFIX) &&
5391 ((ctxt->eflags & X86_EFLAGS_ZF) == X86_EFLAGS_ZF))))
5392 return true;
5393
5394 return false;
5395 }
5396
5397 static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt)
5398 {
5399 int rc;
5400
5401 rc = asm_safe("fwait");
5402
5403 if (unlikely(rc != X86EMUL_CONTINUE))
5404 return emulate_exception(ctxt, MF_VECTOR, 0, false);
5405
5406 return X86EMUL_CONTINUE;
5407 }
5408
5409 static void fetch_possible_mmx_operand(struct x86_emulate_ctxt *ctxt,
5410 struct operand *op)
5411 {
5412 if (op->type == OP_MM)
5413 read_mmx_reg(ctxt, &op->mm_val, op->addr.mm);
5414 }
5415
5416 static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *))
5417 {
5418 ulong flags = (ctxt->eflags & EFLAGS_MASK) | X86_EFLAGS_IF;
5419
5420 if (!(ctxt->d & ByteOp))
5421 fop += __ffs(ctxt->dst.bytes) * FASTOP_SIZE;
5422
5423 asm("push %[flags]; popf; " CALL_NOSPEC " ; pushf; pop %[flags]\n"
5424 : "+a"(ctxt->dst.val), "+d"(ctxt->src.val), [flags]"+D"(flags),
5425 [thunk_target]"+S"(fop), ASM_CALL_CONSTRAINT
5426 : "c"(ctxt->src2.val));
5427
5428 ctxt->eflags = (ctxt->eflags & ~EFLAGS_MASK) | (flags & EFLAGS_MASK);
5429 if (!fop) /* exception is returned in fop variable */
5430 return emulate_de(ctxt);
5431 return X86EMUL_CONTINUE;
5432 }
5433
5434 void init_decode_cache(struct x86_emulate_ctxt *ctxt)
5435 {
5436 memset(&ctxt->rip_relative, 0,
5437 (void *)&ctxt->modrm - (void *)&ctxt->rip_relative);
5438
5439 ctxt->io_read.pos = 0;
5440 ctxt->io_read.end = 0;
5441 ctxt->mem_read.end = 0;
5442 }
5443
5444 int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
5445 {
5446 const struct x86_emulate_ops *ops = ctxt->ops;
5447 int rc = X86EMUL_CONTINUE;
5448 int saved_dst_type = ctxt->dst.type;
5449 unsigned emul_flags;
5450
5451 ctxt->mem_read.pos = 0;
5452
5453 /* LOCK prefix is allowed only with some instructions */
5454 if (ctxt->lock_prefix && (!(ctxt->d & Lock) || ctxt->dst.type != OP_MEM)) {
5455 rc = emulate_ud(ctxt);
5456 goto done;
5457 }
5458
5459 if ((ctxt->d & SrcMask) == SrcMemFAddr && ctxt->src.type != OP_MEM) {
5460 rc = emulate_ud(ctxt);
5461 goto done;
5462 }
5463
5464 emul_flags = ctxt->ops->get_hflags(ctxt);
5465 if (unlikely(ctxt->d &
5466 (No64|Undefined|Sse|Mmx|Intercept|CheckPerm|Priv|Prot|String))) {
5467 if ((ctxt->mode == X86EMUL_MODE_PROT64 && (ctxt->d & No64)) ||
5468 (ctxt->d & Undefined)) {
5469 rc = emulate_ud(ctxt);
5470 goto done;
5471 }
5472
5473 if (((ctxt->d & (Sse|Mmx)) && ((ops->get_cr(ctxt, 0) & X86_CR0_EM)))
5474 || ((ctxt->d & Sse) && !(ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR))) {
5475 rc = emulate_ud(ctxt);
5476 goto done;
5477 }
5478
5479 if ((ctxt->d & (Sse|Mmx)) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) {
5480 rc = emulate_nm(ctxt);
5481 goto done;
5482 }
5483
5484 if (ctxt->d & Mmx) {
5485 rc = flush_pending_x87_faults(ctxt);
5486 if (rc != X86EMUL_CONTINUE)
5487 goto done;
5488 /*
5489 * Now that we know the fpu is exception safe, we can fetch
5490 * operands from it.
5491 */
5492 fetch_possible_mmx_operand(ctxt, &ctxt->src);
5493 fetch_possible_mmx_operand(ctxt, &ctxt->src2);
5494 if (!(ctxt->d & Mov))
5495 fetch_possible_mmx_operand(ctxt, &ctxt->dst);
5496 }
5497
5498 if (unlikely(emul_flags & X86EMUL_GUEST_MASK) && ctxt->intercept) {
5499 rc = emulator_check_intercept(ctxt, ctxt->intercept,
5500 X86_ICPT_PRE_EXCEPT);
5501 if (rc != X86EMUL_CONTINUE)
5502 goto done;
5503 }
5504
5505 /* Instruction can only be executed in protected mode */
5506 if ((ctxt->d & Prot) && ctxt->mode < X86EMUL_MODE_PROT16) {
5507 rc = emulate_ud(ctxt);
5508 goto done;
5509 }
5510
5511 /* Privileged instruction can be executed only in CPL=0 */
5512 if ((ctxt->d & Priv) && ops->cpl(ctxt)) {
5513 if (ctxt->d & PrivUD)
5514 rc = emulate_ud(ctxt);
5515 else
5516 rc = emulate_gp(ctxt, 0);
5517 goto done;
5518 }
5519
5520 /* Do instruction specific permission checks */
5521 if (ctxt->d & CheckPerm) {
5522 rc = ctxt->check_perm(ctxt);
5523 if (rc != X86EMUL_CONTINUE)
5524 goto done;
5525 }
5526
5527 if (unlikely(emul_flags & X86EMUL_GUEST_MASK) && (ctxt->d & Intercept)) {
5528 rc = emulator_check_intercept(ctxt, ctxt->intercept,
5529 X86_ICPT_POST_EXCEPT);
5530 if (rc != X86EMUL_CONTINUE)
5531 goto done;
5532 }
5533
5534 if (ctxt->rep_prefix && (ctxt->d & String)) {
5535 /* All REP prefixes have the same first termination condition */
5536 if (address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) == 0) {
5537 string_registers_quirk(ctxt);
5538 ctxt->eip = ctxt->_eip;
5539 ctxt->eflags &= ~X86_EFLAGS_RF;
5540 goto done;
5541 }
5542 }
5543 }
5544
5545 if ((ctxt->src.type == OP_MEM) && !(ctxt->d & NoAccess)) {
5546 rc = segmented_read(ctxt, ctxt->src.addr.mem,
5547 ctxt->src.valptr, ctxt->src.bytes);
5548 if (rc != X86EMUL_CONTINUE)
5549 goto done;
5550 ctxt->src.orig_val64 = ctxt->src.val64;
5551 }
5552
5553 if (ctxt->src2.type == OP_MEM) {
5554 rc = segmented_read(ctxt, ctxt->src2.addr.mem,
5555 &ctxt->src2.val, ctxt->src2.bytes);
5556 if (rc != X86EMUL_CONTINUE)
5557 goto done;
5558 }
5559
5560 if ((ctxt->d & DstMask) == ImplicitOps)
5561 goto special_insn;
5562
5563
5564 if ((ctxt->dst.type == OP_MEM) && !(ctxt->d & Mov)) {
5565 /* optimisation - avoid slow emulated read if Mov */
5566 rc = segmented_read(ctxt, ctxt->dst.addr.mem,
5567 &ctxt->dst.val, ctxt->dst.bytes);
5568 if (rc != X86EMUL_CONTINUE) {
5569 if (!(ctxt->d & NoWrite) &&
5570 rc == X86EMUL_PROPAGATE_FAULT &&
5571 ctxt->exception.vector == PF_VECTOR)
5572 ctxt->exception.error_code |= PFERR_WRITE_MASK;
5573 goto done;
5574 }
5575 }
5576 /* Copy full 64-bit value for CMPXCHG8B. */
5577 ctxt->dst.orig_val64 = ctxt->dst.val64;
5578
5579 special_insn:
5580
5581 if (unlikely(emul_flags & X86EMUL_GUEST_MASK) && (ctxt->d & Intercept)) {
5582 rc = emulator_check_intercept(ctxt, ctxt->intercept,
5583 X86_ICPT_POST_MEMACCESS);
5584 if (rc != X86EMUL_CONTINUE)
5585 goto done;
5586 }
5587
5588 if (ctxt->rep_prefix && (ctxt->d & String))
5589 ctxt->eflags |= X86_EFLAGS_RF;
5590 else
5591 ctxt->eflags &= ~X86_EFLAGS_RF;
5592
5593 if (ctxt->execute) {
5594 if (ctxt->d & Fastop) {
5595 void (*fop)(struct fastop *) = (void *)ctxt->execute;
5596 rc = fastop(ctxt, fop);
5597 if (rc != X86EMUL_CONTINUE)
5598 goto done;
5599 goto writeback;
5600 }
5601 rc = ctxt->execute(ctxt);
5602 if (rc != X86EMUL_CONTINUE)
5603 goto done;
5604 goto writeback;
5605 }
5606
5607 if (ctxt->opcode_len == 2)
5608 goto twobyte_insn;
5609 else if (ctxt->opcode_len == 3)
5610 goto threebyte_insn;
5611
5612 switch (ctxt->b) {
5613 case 0x70 ... 0x7f: /* jcc (short) */
5614 if (test_cc(ctxt->b, ctxt->eflags))
5615 rc = jmp_rel(ctxt, ctxt->src.val);
5616 break;
5617 case 0x8d: /* lea r16/r32, m */
5618 ctxt->dst.val = ctxt->src.addr.mem.ea;
5619 break;
5620 case 0x90 ... 0x97: /* nop / xchg reg, rax */
5621 if (ctxt->dst.addr.reg == reg_rmw(ctxt, VCPU_REGS_RAX))
5622 ctxt->dst.type = OP_NONE;
5623 else
5624 rc = em_xchg(ctxt);
5625 break;
5626 case 0x98: /* cbw/cwde/cdqe */
5627 switch (ctxt->op_bytes) {
5628 case 2: ctxt->dst.val = (s8)ctxt->dst.val; break;
5629 case 4: ctxt->dst.val = (s16)ctxt->dst.val; break;
5630 case 8: ctxt->dst.val = (s32)ctxt->dst.val; break;
5631 }
5632 break;
5633 case 0xcc: /* int3 */
5634 rc = emulate_int(ctxt, 3);
5635 break;
5636 case 0xcd: /* int n */
5637 rc = emulate_int(ctxt, ctxt->src.val);
5638 break;
5639 case 0xce: /* into */
5640 if (ctxt->eflags & X86_EFLAGS_OF)
5641 rc = emulate_int(ctxt, 4);
5642 break;
5643 case 0xe9: /* jmp rel */
5644 case 0xeb: /* jmp rel short */
5645 rc = jmp_rel(ctxt, ctxt->src.val);
5646 ctxt->dst.type = OP_NONE; /* Disable writeback. */
5647 break;
5648 case 0xf4: /* hlt */
5649 ctxt->ops->halt(ctxt);
5650 break;
5651 case 0xf5: /* cmc */
5652 /* complement carry flag from eflags reg */
5653 ctxt->eflags ^= X86_EFLAGS_CF;
5654 break;
5655 case 0xf8: /* clc */
5656 ctxt->eflags &= ~X86_EFLAGS_CF;
5657 break;
5658 case 0xf9: /* stc */
5659 ctxt->eflags |= X86_EFLAGS_CF;
5660 break;
5661 case 0xfc: /* cld */
5662 ctxt->eflags &= ~X86_EFLAGS_DF;
5663 break;
5664 case 0xfd: /* std */
5665 ctxt->eflags |= X86_EFLAGS_DF;
5666 break;
5667 default:
5668 goto cannot_emulate;
5669 }
5670
5671 if (rc != X86EMUL_CONTINUE)
5672 goto done;
5673
5674 writeback:
5675 if (ctxt->d & SrcWrite) {
5676 BUG_ON(ctxt->src.type == OP_MEM || ctxt->src.type == OP_MEM_STR);
5677 rc = writeback(ctxt, &ctxt->src);
5678 if (rc != X86EMUL_CONTINUE)
5679 goto done;
5680 }
5681 if (!(ctxt->d & NoWrite)) {
5682 rc = writeback(ctxt, &ctxt->dst);
5683 if (rc != X86EMUL_CONTINUE)
5684 goto done;
5685 }
5686
5687 /*
5688 * restore dst type in case the decoding will be reused
5689 * (happens for string instruction )
5690 */
5691 ctxt->dst.type = saved_dst_type;
5692
5693 if ((ctxt->d & SrcMask) == SrcSI)
5694 string_addr_inc(ctxt, VCPU_REGS_RSI, &ctxt->src);
5695
5696 if ((ctxt->d & DstMask) == DstDI)
5697 string_addr_inc(ctxt, VCPU_REGS_RDI, &ctxt->dst);
5698
5699 if (ctxt->rep_prefix && (ctxt->d & String)) {
5700 unsigned int count;
5701 struct read_cache *r = &ctxt->io_read;
5702 if ((ctxt->d & SrcMask) == SrcSI)
5703 count = ctxt->src.count;
5704 else
5705 count = ctxt->dst.count;
5706 register_address_increment(ctxt, VCPU_REGS_RCX, -count);
5707
5708 if (!string_insn_completed(ctxt)) {
5709 /*
5710 * Re-enter guest when pio read ahead buffer is empty
5711 * or, if it is not used, after each 1024 iteration.
5712 */
5713 if ((r->end != 0 || reg_read(ctxt, VCPU_REGS_RCX) & 0x3ff) &&
5714 (r->end == 0 || r->end != r->pos)) {
5715 /*
5716 * Reset read cache. Usually happens before
5717 * decode, but since instruction is restarted
5718 * we have to do it here.
5719 */
5720 ctxt->mem_read.end = 0;
5721 writeback_registers(ctxt);
5722 return EMULATION_RESTART;
5723 }
5724 goto done; /* skip rip writeback */
5725 }
5726 ctxt->eflags &= ~X86_EFLAGS_RF;
5727 }
5728
5729 ctxt->eip = ctxt->_eip;
5730
5731 done:
5732 if (rc == X86EMUL_PROPAGATE_FAULT) {
5733 WARN_ON(ctxt->exception.vector > 0x1f);
5734 ctxt->have_exception = true;
5735 }
5736 if (rc == X86EMUL_INTERCEPTED)
5737 return EMULATION_INTERCEPTED;
5738
5739 if (rc == X86EMUL_CONTINUE)
5740 writeback_registers(ctxt);
5741
5742 return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
5743
5744 twobyte_insn:
5745 switch (ctxt->b) {
5746 case 0x09: /* wbinvd */
5747 (ctxt->ops->wbinvd)(ctxt);
5748 break;
5749 case 0x08: /* invd */
5750 case 0x0d: /* GrpP (prefetch) */
5751 case 0x18: /* Grp16 (prefetch/nop) */
5752 case 0x1f: /* nop */
5753 break;
5754 case 0x20: /* mov cr, reg */
5755 ctxt->dst.val = ops->get_cr(ctxt, ctxt->modrm_reg);
5756 break;
5757 case 0x21: /* mov from dr to reg */
5758 ops->get_dr(ctxt, ctxt->modrm_reg, &ctxt->dst.val);
5759 break;
5760 case 0x40 ... 0x4f: /* cmov */
5761 if (test_cc(ctxt->b, ctxt->eflags))
5762 ctxt->dst.val = ctxt->src.val;
5763 else if (ctxt->op_bytes != 4)
5764 ctxt->dst.type = OP_NONE; /* no writeback */
5765 break;
5766 case 0x80 ... 0x8f: /* jnz rel, etc*/
5767 if (test_cc(ctxt->b, ctxt->eflags))
5768 rc = jmp_rel(ctxt, ctxt->src.val);
5769 break;
5770 case 0x90 ... 0x9f: /* setcc r/m8 */
5771 ctxt->dst.val = test_cc(ctxt->b, ctxt->eflags);
5772 break;
5773 case 0xb6 ... 0xb7: /* movzx */
5774 ctxt->dst.bytes = ctxt->op_bytes;
5775 ctxt->dst.val = (ctxt->src.bytes == 1) ? (u8) ctxt->src.val
5776 : (u16) ctxt->src.val;
5777 break;
5778 case 0xbe ... 0xbf: /* movsx */
5779 ctxt->dst.bytes = ctxt->op_bytes;
5780 ctxt->dst.val = (ctxt->src.bytes == 1) ? (s8) ctxt->src.val :
5781 (s16) ctxt->src.val;
5782 break;
5783 default:
5784 goto cannot_emulate;
5785 }
5786
5787 threebyte_insn:
5788
5789 if (rc != X86EMUL_CONTINUE)
5790 goto done;
5791
5792 goto writeback;
5793
5794 cannot_emulate:
5795 return EMULATION_FAILED;
5796 }
5797
5798 void emulator_invalidate_register_cache(struct x86_emulate_ctxt *ctxt)
5799 {
5800 invalidate_registers(ctxt);
5801 }
5802
5803 void emulator_writeback_register_cache(struct x86_emulate_ctxt *ctxt)
5804 {
5805 writeback_registers(ctxt);
5806 }
5807
5808 bool emulator_can_use_gpa(struct x86_emulate_ctxt *ctxt)
5809 {
5810 if (ctxt->rep_prefix && (ctxt->d & String))
5811 return false;
5812
5813 if (ctxt->d & TwoMemOp)
5814 return false;
5815
5816 return true;
5817 }
Ubuntu Disco kernel mirror for Proxmox VE and PMG