projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
KVM: SVM: Add intercept checks for remaining twobyte instructions
[deliverable/linux.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 <linux/module.h>
26 #include <asm/kvm_emulate.h>
27
28 #include "x86.h"
29 #include "tss.h"
30
31 /*
32 * Opcode effective-address decode tables.
33 * Note that we only emulate instructions that have at least one memory
34 * operand (excluding implicit stack references). We assume that stack
35 * references and instruction fetches will never occur in special memory
36 * areas that require emulation. So, for example, 'mov <imm>,<reg>' need
37 * not be handled.
38 */
39
40 /* Operand sizes: 8-bit operands or specified/overridden size. */
41 #define ByteOp (1<<0) /* 8-bit operands. */
42 /* Destination operand type. */
43 #define ImplicitOps (1<<1) /* Implicit in opcode. No generic decode. */
44 #define DstReg (2<<1) /* Register operand. */
45 #define DstMem (3<<1) /* Memory operand. */
46 #define DstAcc (4<<1) /* Destination Accumulator */
47 #define DstDI (5<<1) /* Destination is in ES:(E)DI */
48 #define DstMem64 (6<<1) /* 64bit memory operand */
49 #define DstImmUByte (7<<1) /* 8-bit unsigned immediate operand */
50 #define DstMask (7<<1)
51 /* Source operand type. */
52 #define SrcNone (0<<4) /* No source operand. */
53 #define SrcReg (1<<4) /* Register operand. */
54 #define SrcMem (2<<4) /* Memory operand. */
55 #define SrcMem16 (3<<4) /* Memory operand (16-bit). */
56 #define SrcMem32 (4<<4) /* Memory operand (32-bit). */
57 #define SrcImm (5<<4) /* Immediate operand. */
58 #define SrcImmByte (6<<4) /* 8-bit sign-extended immediate operand. */
59 #define SrcOne (7<<4) /* Implied '1' */
60 #define SrcImmUByte (8<<4) /* 8-bit unsigned immediate operand. */
61 #define SrcImmU (9<<4) /* Immediate operand, unsigned */
62 #define SrcSI (0xa<<4) /* Source is in the DS:RSI */
63 #define SrcImmFAddr (0xb<<4) /* Source is immediate far address */
64 #define SrcMemFAddr (0xc<<4) /* Source is far address in memory */
65 #define SrcAcc (0xd<<4) /* Source Accumulator */
66 #define SrcImmU16 (0xe<<4) /* Immediate operand, unsigned, 16 bits */
67 #define SrcMask (0xf<<4)
68 /* Generic ModRM decode. */
69 #define ModRM (1<<8)
70 /* Destination is only written; never read. */
71 #define Mov (1<<9)
72 #define BitOp (1<<10)
73 #define MemAbs (1<<11) /* Memory operand is absolute displacement */
74 #define String (1<<12) /* String instruction (rep capable) */
75 #define Stack (1<<13) /* Stack instruction (push/pop) */
76 #define Group (1<<14) /* Bits 3:5 of modrm byte extend opcode */
77 #define GroupDual (1<<15) /* Alternate decoding of mod == 3 */
78 #define Prefix (1<<16) /* Instruction varies with 66/f2/f3 prefix */
79 #define Sse (1<<17) /* SSE Vector instruction */
80 #define RMExt (1<<18) /* Opcode extension in ModRM r/m if mod == 3 */
81 /* Misc flags */
82 #define Prot (1<<21) /* instruction generates #UD if not in prot-mode */
83 #define VendorSpecific (1<<22) /* Vendor specific instruction */
84 #define NoAccess (1<<23) /* Don't access memory (lea/invlpg/verr etc) */
85 #define Op3264 (1<<24) /* Operand is 64b in long mode, 32b otherwise */
86 #define Undefined (1<<25) /* No Such Instruction */
87 #define Lock (1<<26) /* lock prefix is allowed for the instruction */
88 #define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */
89 #define No64 (1<<28)
90 /* Source 2 operand type */
91 #define Src2None (0<<29)
92 #define Src2CL (1<<29)
93 #define Src2ImmByte (2<<29)
94 #define Src2One (3<<29)
95 #define Src2Imm (4<<29)
96 #define Src2Mask (7<<29)
97
98 #define X2(x...) x, x
99 #define X3(x...) X2(x), x
100 #define X4(x...) X2(x), X2(x)
101 #define X5(x...) X4(x), x
102 #define X6(x...) X4(x), X2(x)
103 #define X7(x...) X4(x), X3(x)
104 #define X8(x...) X4(x), X4(x)
105 #define X16(x...) X8(x), X8(x)
106
107 struct opcode {
108 u32 flags;
109 u8 intercept;
110 union {
111 int (*execute)(struct x86_emulate_ctxt *ctxt);
112 struct opcode *group;
113 struct group_dual *gdual;
114 struct gprefix *gprefix;
115 } u;
116 int (*check_perm)(struct x86_emulate_ctxt *ctxt);
117 };
118
119 struct group_dual {
120 struct opcode mod012[8];
121 struct opcode mod3[8];
122 };
123
124 struct gprefix {
125 struct opcode pfx_no;
126 struct opcode pfx_66;
127 struct opcode pfx_f2;
128 struct opcode pfx_f3;
129 };
130
131 /* EFLAGS bit definitions. */
132 #define EFLG_ID (1<<21)
133 #define EFLG_VIP (1<<20)
134 #define EFLG_VIF (1<<19)
135 #define EFLG_AC (1<<18)
136 #define EFLG_VM (1<<17)
137 #define EFLG_RF (1<<16)
138 #define EFLG_IOPL (3<<12)
139 #define EFLG_NT (1<<14)
140 #define EFLG_OF (1<<11)
141 #define EFLG_DF (1<<10)
142 #define EFLG_IF (1<<9)
143 #define EFLG_TF (1<<8)
144 #define EFLG_SF (1<<7)
145 #define EFLG_ZF (1<<6)
146 #define EFLG_AF (1<<4)
147 #define EFLG_PF (1<<2)
148 #define EFLG_CF (1<<0)
149
150 #define EFLG_RESERVED_ZEROS_MASK 0xffc0802a
151 #define EFLG_RESERVED_ONE_MASK 2
152
153 /*
154 * Instruction emulation:
155 * Most instructions are emulated directly via a fragment of inline assembly
156 * code. This allows us to save/restore EFLAGS and thus very easily pick up
157 * any modified flags.
158 */
159
160 #if defined(CONFIG_X86_64)
161 #define _LO32 "k" /* force 32-bit operand */
162 #define _STK "%%rsp" /* stack pointer */
163 #elif defined(__i386__)
164 #define _LO32 "" /* force 32-bit operand */
165 #define _STK "%%esp" /* stack pointer */
166 #endif
167
168 /*
169 * These EFLAGS bits are restored from saved value during emulation, and
170 * any changes are written back to the saved value after emulation.
171 */
172 #define EFLAGS_MASK (EFLG_OF|EFLG_SF|EFLG_ZF|EFLG_AF|EFLG_PF|EFLG_CF)
173
174 /* Before executing instruction: restore necessary bits in EFLAGS. */
175 #define _PRE_EFLAGS(_sav, _msk, _tmp) \
176 /* EFLAGS = (_sav & _msk) | (EFLAGS & ~_msk); _sav &= ~_msk; */ \
177 "movl %"_sav",%"_LO32 _tmp"; " \
178 "push %"_tmp"; " \
179 "push %"_tmp"; " \
180 "movl %"_msk",%"_LO32 _tmp"; " \
181 "andl %"_LO32 _tmp",("_STK"); " \
182 "pushf; " \
183 "notl %"_LO32 _tmp"; " \
184 "andl %"_LO32 _tmp",("_STK"); " \
185 "andl %"_LO32 _tmp","__stringify(BITS_PER_LONG/4)"("_STK"); " \
186 "pop %"_tmp"; " \
187 "orl %"_LO32 _tmp",("_STK"); " \
188 "popf; " \
189 "pop %"_sav"; "
190
191 /* After executing instruction: write-back necessary bits in EFLAGS. */
192 #define _POST_EFLAGS(_sav, _msk, _tmp) \
193 /* _sav |= EFLAGS & _msk; */ \
194 "pushf; " \
195 "pop %"_tmp"; " \
196 "andl %"_msk",%"_LO32 _tmp"; " \
197 "orl %"_LO32 _tmp",%"_sav"; "
198
199 #ifdef CONFIG_X86_64
200 #define ON64(x) x
201 #else
202 #define ON64(x)
203 #endif
204
205 #define ____emulate_2op(_op, _src, _dst, _eflags, _x, _y, _suffix, _dsttype) \
206 do { \
207 __asm__ __volatile__ ( \
208 _PRE_EFLAGS("0", "4", "2") \
209 _op _suffix " %"_x"3,%1; " \
210 _POST_EFLAGS("0", "4", "2") \
211 : "=m" (_eflags), "+q" (*(_dsttype*)&(_dst).val),\
212 "=&r" (_tmp) \
213 : _y ((_src).val), "i" (EFLAGS_MASK)); \
214 } while (0)
215
216
217 /* Raw emulation: instruction has two explicit operands. */
218 #define __emulate_2op_nobyte(_op,_src,_dst,_eflags,_wx,_wy,_lx,_ly,_qx,_qy) \
219 do { \
220 unsigned long _tmp; \
221 \
222 switch ((_dst).bytes) { \
223 case 2: \
224 ____emulate_2op(_op,_src,_dst,_eflags,_wx,_wy,"w",u16);\
225 break; \
226 case 4: \
227 ____emulate_2op(_op,_src,_dst,_eflags,_lx,_ly,"l",u32);\
228 break; \
229 case 8: \
230 ON64(____emulate_2op(_op,_src,_dst,_eflags,_qx,_qy,"q",u64)); \
231 break; \
232 } \
233 } while (0)
234
235 #define __emulate_2op(_op,_src,_dst,_eflags,_bx,_by,_wx,_wy,_lx,_ly,_qx,_qy) \
236 do { \
237 unsigned long _tmp; \
238 switch ((_dst).bytes) { \
239 case 1: \
240 ____emulate_2op(_op,_src,_dst,_eflags,_bx,_by,"b",u8); \
241 break; \
242 default: \
243 __emulate_2op_nobyte(_op, _src, _dst, _eflags, \
244 _wx, _wy, _lx, _ly, _qx, _qy); \
245 break; \
246 } \
247 } while (0)
248
249 /* Source operand is byte-sized and may be restricted to just %cl. */
250 #define emulate_2op_SrcB(_op, _src, _dst, _eflags) \
251 __emulate_2op(_op, _src, _dst, _eflags, \
252 "b", "c", "b", "c", "b", "c", "b", "c")
253
254 /* Source operand is byte, word, long or quad sized. */
255 #define emulate_2op_SrcV(_op, _src, _dst, _eflags) \
256 __emulate_2op(_op, _src, _dst, _eflags, \
257 "b", "q", "w", "r", _LO32, "r", "", "r")
258
259 /* Source operand is word, long or quad sized. */
260 #define emulate_2op_SrcV_nobyte(_op, _src, _dst, _eflags) \
261 __emulate_2op_nobyte(_op, _src, _dst, _eflags, \
262 "w", "r", _LO32, "r", "", "r")
263
264 /* Instruction has three operands and one operand is stored in ECX register */
265 #define __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, _suffix, _type) \
266 do { \
267 unsigned long _tmp; \
268 _type _clv = (_cl).val; \
269 _type _srcv = (_src).val; \
270 _type _dstv = (_dst).val; \
271 \
272 __asm__ __volatile__ ( \
273 _PRE_EFLAGS("0", "5", "2") \
274 _op _suffix " %4,%1 \n" \
275 _POST_EFLAGS("0", "5", "2") \
276 : "=m" (_eflags), "+r" (_dstv), "=&r" (_tmp) \
277 : "c" (_clv) , "r" (_srcv), "i" (EFLAGS_MASK) \
278 ); \
279 \
280 (_cl).val = (unsigned long) _clv; \
281 (_src).val = (unsigned long) _srcv; \
282 (_dst).val = (unsigned long) _dstv; \
283 } while (0)
284
285 #define emulate_2op_cl(_op, _cl, _src, _dst, _eflags) \
286 do { \
287 switch ((_dst).bytes) { \
288 case 2: \
289 __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \
290 "w", unsigned short); \
291 break; \
292 case 4: \
293 __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \
294 "l", unsigned int); \
295 break; \
296 case 8: \
297 ON64(__emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \
298 "q", unsigned long)); \
299 break; \
300 } \
301 } while (0)
302
303 #define __emulate_1op(_op, _dst, _eflags, _suffix) \
304 do { \
305 unsigned long _tmp; \
306 \
307 __asm__ __volatile__ ( \
308 _PRE_EFLAGS("0", "3", "2") \
309 _op _suffix " %1; " \
310 _POST_EFLAGS("0", "3", "2") \
311 : "=m" (_eflags), "+m" ((_dst).val), \
312 "=&r" (_tmp) \
313 : "i" (EFLAGS_MASK)); \
314 } while (0)
315
316 /* Instruction has only one explicit operand (no source operand). */
317 #define emulate_1op(_op, _dst, _eflags) \
318 do { \
319 switch ((_dst).bytes) { \
320 case 1: __emulate_1op(_op, _dst, _eflags, "b"); break; \
321 case 2: __emulate_1op(_op, _dst, _eflags, "w"); break; \
322 case 4: __emulate_1op(_op, _dst, _eflags, "l"); break; \
323 case 8: ON64(__emulate_1op(_op, _dst, _eflags, "q")); break; \
324 } \
325 } while (0)
326
327 #define __emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags, _suffix) \
328 do { \
329 unsigned long _tmp; \
330 \
331 __asm__ __volatile__ ( \
332 _PRE_EFLAGS("0", "4", "1") \
333 _op _suffix " %5; " \
334 _POST_EFLAGS("0", "4", "1") \
335 : "=m" (_eflags), "=&r" (_tmp), \
336 "+a" (_rax), "+d" (_rdx) \
337 : "i" (EFLAGS_MASK), "m" ((_src).val), \
338 "a" (_rax), "d" (_rdx)); \
339 } while (0)
340
341 #define __emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, _eflags, _suffix, _ex) \
342 do { \
343 unsigned long _tmp; \
344 \
345 __asm__ __volatile__ ( \
346 _PRE_EFLAGS("0", "5", "1") \
347 "1: \n\t" \
348 _op _suffix " %6; " \
349 "2: \n\t" \
350 _POST_EFLAGS("0", "5", "1") \
351 ".pushsection .fixup,\"ax\" \n\t" \
352 "3: movb $1, %4 \n\t" \
353 "jmp 2b \n\t" \
354 ".popsection \n\t" \
355 _ASM_EXTABLE(1b, 3b) \
356 : "=m" (_eflags), "=&r" (_tmp), \
357 "+a" (_rax), "+d" (_rdx), "+qm"(_ex) \
358 : "i" (EFLAGS_MASK), "m" ((_src).val), \
359 "a" (_rax), "d" (_rdx)); \
360 } while (0)
361
362 /* instruction has only one source operand, destination is implicit (e.g. mul, div, imul, idiv) */
363 #define emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags) \
364 do { \
365 switch((_src).bytes) { \
366 case 1: __emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags, "b"); break; \
367 case 2: __emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags, "w"); break; \
368 case 4: __emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags, "l"); break; \
369 case 8: ON64(__emulate_1op_rax_rdx(_op, _src, _rax, _rdx, _eflags, "q")); break; \
370 } \
371 } while (0)
372
373 #define emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, _eflags, _ex) \
374 do { \
375 switch((_src).bytes) { \
376 case 1: \
377 __emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, \
378 _eflags, "b", _ex); \
379 break; \
380 case 2: \
381 __emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, \
382 _eflags, "w", _ex); \
383 break; \
384 case 4: \
385 __emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, \
386 _eflags, "l", _ex); \
387 break; \
388 case 8: ON64( \
389 __emulate_1op_rax_rdx_ex(_op, _src, _rax, _rdx, \
390 _eflags, "q", _ex)); \
391 break; \
392 } \
393 } while (0)
394
395 /* Fetch next part of the instruction being emulated. */
396 #define insn_fetch(_type, _size, _eip) \
397 ({ unsigned long _x; \
398 rc = do_insn_fetch(ctxt, ops, (_eip), &_x, (_size)); \
399 if (rc != X86EMUL_CONTINUE) \
400 goto done; \
401 (_eip) += (_size); \
402 (_type)_x; \
403 })
404
405 #define insn_fetch_arr(_arr, _size, _eip) \
406 ({ rc = do_insn_fetch(ctxt, ops, (_eip), _arr, (_size)); \
407 if (rc != X86EMUL_CONTINUE) \
408 goto done; \
409 (_eip) += (_size); \
410 })
411
412 static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt,
413 enum x86_intercept intercept,
414 enum x86_intercept_stage stage)
415 {
416 struct x86_instruction_info info = {
417 .intercept = intercept,
418 .rep_prefix = ctxt->decode.rep_prefix,
419 .modrm_mod = ctxt->decode.modrm_mod,
420 .modrm_reg = ctxt->decode.modrm_reg,
421 .modrm_rm = ctxt->decode.modrm_rm,
422 .src_val = ctxt->decode.src.val64,
423 .src_bytes = ctxt->decode.src.bytes,
424 .dst_bytes = ctxt->decode.dst.bytes,
425 .ad_bytes = ctxt->decode.ad_bytes,
426 .next_rip = ctxt->eip,
427 };
428
429 return ctxt->ops->intercept(ctxt->vcpu, &info, stage);
430 }
431
432 static inline unsigned long ad_mask(struct decode_cache *c)
433 {
434 return (1UL << (c->ad_bytes << 3)) - 1;
435 }
436
437 /* Access/update address held in a register, based on addressing mode. */
438 static inline unsigned long
439 address_mask(struct decode_cache *c, unsigned long reg)
440 {
441 if (c->ad_bytes == sizeof(unsigned long))
442 return reg;
443 else
444 return reg & ad_mask(c);
445 }
446
447 static inline unsigned long
448 register_address(struct decode_cache *c, unsigned long reg)
449 {
450 return address_mask(c, reg);
451 }
452
453 static inline void
454 register_address_increment(struct decode_cache *c, unsigned long *reg, int inc)
455 {
456 if (c->ad_bytes == sizeof(unsigned long))
457 *reg += inc;
458 else
459 *reg = (*reg & ~ad_mask(c)) | ((*reg + inc) & ad_mask(c));
460 }
461
462 static inline void jmp_rel(struct decode_cache *c, int rel)
463 {
464 register_address_increment(c, &c->eip, rel);
465 }
466
467 static void set_seg_override(struct decode_cache *c, int seg)
468 {
469 c->has_seg_override = true;
470 c->seg_override = seg;
471 }
472
473 static unsigned long seg_base(struct x86_emulate_ctxt *ctxt,
474 struct x86_emulate_ops *ops, int seg)
475 {
476 if (ctxt->mode == X86EMUL_MODE_PROT64 && seg < VCPU_SREG_FS)
477 return 0;
478
479 return ops->get_cached_segment_base(seg, ctxt->vcpu);
480 }
481
482 static unsigned seg_override(struct x86_emulate_ctxt *ctxt,
483 struct x86_emulate_ops *ops,
484 struct decode_cache *c)
485 {
486 if (!c->has_seg_override)
487 return 0;
488
489 return c->seg_override;
490 }
491
492 static ulong linear(struct x86_emulate_ctxt *ctxt,
493 struct segmented_address addr)
494 {
495 struct decode_cache *c = &ctxt->decode;
496 ulong la;
497
498 la = seg_base(ctxt, ctxt->ops, addr.seg) + addr.ea;
499 if (c->ad_bytes != 8)
500 la &= (u32)-1;
501 return la;
502 }
503
504 static int emulate_exception(struct x86_emulate_ctxt *ctxt, int vec,
505 u32 error, bool valid)
506 {
507 ctxt->exception.vector = vec;
508 ctxt->exception.error_code = error;
509 ctxt->exception.error_code_valid = valid;
510 return X86EMUL_PROPAGATE_FAULT;
511 }
512
513 static int emulate_db(struct x86_emulate_ctxt *ctxt)
514 {
515 return emulate_exception(ctxt, DB_VECTOR, 0, false);
516 }
517
518 static int emulate_gp(struct x86_emulate_ctxt *ctxt, int err)
519 {
520 return emulate_exception(ctxt, GP_VECTOR, err, true);
521 }
522
523 static int emulate_ud(struct x86_emulate_ctxt *ctxt)
524 {
525 return emulate_exception(ctxt, UD_VECTOR, 0, false);
526 }
527
528 static int emulate_ts(struct x86_emulate_ctxt *ctxt, int err)
529 {
530 return emulate_exception(ctxt, TS_VECTOR, err, true);
531 }
532
533 static int emulate_de(struct x86_emulate_ctxt *ctxt)
534 {
535 return emulate_exception(ctxt, DE_VECTOR, 0, false);
536 }
537
538 static int emulate_nm(struct x86_emulate_ctxt *ctxt)
539 {
540 return emulate_exception(ctxt, NM_VECTOR, 0, false);
541 }
542
543 static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
544 struct x86_emulate_ops *ops,
545 unsigned long eip, u8 *dest)
546 {
547 struct fetch_cache *fc = &ctxt->decode.fetch;
548 int rc;
549 int size, cur_size;
550
551 if (eip == fc->end) {
552 cur_size = fc->end - fc->start;
553 size = min(15UL - cur_size, PAGE_SIZE - offset_in_page(eip));
554 rc = ops->fetch(ctxt->cs_base + eip, fc->data + cur_size,
555 size, ctxt->vcpu, &ctxt->exception);
556 if (rc != X86EMUL_CONTINUE)
557 return rc;
558 fc->end += size;
559 }
560 *dest = fc->data[eip - fc->start];
561 return X86EMUL_CONTINUE;
562 }
563
564 static int do_insn_fetch(struct x86_emulate_ctxt *ctxt,
565 struct x86_emulate_ops *ops,
566 unsigned long eip, void *dest, unsigned size)
567 {
568 int rc;
569
570 /* x86 instructions are limited to 15 bytes. */
571 if (eip + size - ctxt->eip > 15)
572 return X86EMUL_UNHANDLEABLE;
573 while (size--) {
574 rc = do_fetch_insn_byte(ctxt, ops, eip++, dest++);
575 if (rc != X86EMUL_CONTINUE)
576 return rc;
577 }
578 return X86EMUL_CONTINUE;
579 }
580
581 /*
582 * Given the 'reg' portion of a ModRM byte, and a register block, return a
583 * pointer into the block that addresses the relevant register.
584 * @highbyte_regs specifies whether to decode AH,CH,DH,BH.
585 */
586 static void *decode_register(u8 modrm_reg, unsigned long *regs,
587 int highbyte_regs)
588 {
589 void *p;
590
591 p = &regs[modrm_reg];
592 if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8)
593 p = (unsigned char *)&regs[modrm_reg & 3] + 1;
594 return p;
595 }
596
597 static int read_descriptor(struct x86_emulate_ctxt *ctxt,
598 struct x86_emulate_ops *ops,
599 struct segmented_address addr,
600 u16 *size, unsigned long *address, int op_bytes)
601 {
602 int rc;
603
604 if (op_bytes == 2)
605 op_bytes = 3;
606 *address = 0;
607 rc = ops->read_std(linear(ctxt, addr), (unsigned long *)size, 2,
608 ctxt->vcpu, &ctxt->exception);
609 if (rc != X86EMUL_CONTINUE)
610 return rc;
611 addr.ea += 2;
612 rc = ops->read_std(linear(ctxt, addr), address, op_bytes,
613 ctxt->vcpu, &ctxt->exception);
614 return rc;
615 }
616
617 static int test_cc(unsigned int condition, unsigned int flags)
618 {
619 int rc = 0;
620
621 switch ((condition & 15) >> 1) {
622 case 0: /* o */
623 rc |= (flags & EFLG_OF);
624 break;
625 case 1: /* b/c/nae */
626 rc |= (flags & EFLG_CF);
627 break;
628 case 2: /* z/e */
629 rc |= (flags & EFLG_ZF);
630 break;
631 case 3: /* be/na */
632 rc |= (flags & (EFLG_CF|EFLG_ZF));
633 break;
634 case 4: /* s */
635 rc |= (flags & EFLG_SF);
636 break;
637 case 5: /* p/pe */
638 rc |= (flags & EFLG_PF);
639 break;
640 case 7: /* le/ng */
641 rc |= (flags & EFLG_ZF);
642 /* fall through */
643 case 6: /* l/nge */
644 rc |= (!(flags & EFLG_SF) != !(flags & EFLG_OF));
645 break;
646 }
647
648 /* Odd condition identifiers (lsb == 1) have inverted sense. */
649 return (!!rc ^ (condition & 1));
650 }
651
652 static void fetch_register_operand(struct operand *op)
653 {
654 switch (op->bytes) {
655 case 1:
656 op->val = *(u8 *)op->addr.reg;
657 break;
658 case 2:
659 op->val = *(u16 *)op->addr.reg;
660 break;
661 case 4:
662 op->val = *(u32 *)op->addr.reg;
663 break;
664 case 8:
665 op->val = *(u64 *)op->addr.reg;
666 break;
667 }
668 }
669
670 static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg)
671 {
672 ctxt->ops->get_fpu(ctxt);
673 switch (reg) {
674 case 0: asm("movdqu %%xmm0, %0" : "=m"(*data)); break;
675 case 1: asm("movdqu %%xmm1, %0" : "=m"(*data)); break;
676 case 2: asm("movdqu %%xmm2, %0" : "=m"(*data)); break;
677 case 3: asm("movdqu %%xmm3, %0" : "=m"(*data)); break;
678 case 4: asm("movdqu %%xmm4, %0" : "=m"(*data)); break;
679 case 5: asm("movdqu %%xmm5, %0" : "=m"(*data)); break;
680 case 6: asm("movdqu %%xmm6, %0" : "=m"(*data)); break;
681 case 7: asm("movdqu %%xmm7, %0" : "=m"(*data)); break;
682 #ifdef CONFIG_X86_64
683 case 8: asm("movdqu %%xmm8, %0" : "=m"(*data)); break;
684 case 9: asm("movdqu %%xmm9, %0" : "=m"(*data)); break;
685 case 10: asm("movdqu %%xmm10, %0" : "=m"(*data)); break;
686 case 11: asm("movdqu %%xmm11, %0" : "=m"(*data)); break;
687 case 12: asm("movdqu %%xmm12, %0" : "=m"(*data)); break;
688 case 13: asm("movdqu %%xmm13, %0" : "=m"(*data)); break;
689 case 14: asm("movdqu %%xmm14, %0" : "=m"(*data)); break;
690 case 15: asm("movdqu %%xmm15, %0" : "=m"(*data)); break;
691 #endif
692 default: BUG();
693 }
694 ctxt->ops->put_fpu(ctxt);
695 }
696
697 static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
698 int reg)
699 {
700 ctxt->ops->get_fpu(ctxt);
701 switch (reg) {
702 case 0: asm("movdqu %0, %%xmm0" : : "m"(*data)); break;
703 case 1: asm("movdqu %0, %%xmm1" : : "m"(*data)); break;
704 case 2: asm("movdqu %0, %%xmm2" : : "m"(*data)); break;
705 case 3: asm("movdqu %0, %%xmm3" : : "m"(*data)); break;
706 case 4: asm("movdqu %0, %%xmm4" : : "m"(*data)); break;
707 case 5: asm("movdqu %0, %%xmm5" : : "m"(*data)); break;
708 case 6: asm("movdqu %0, %%xmm6" : : "m"(*data)); break;
709 case 7: asm("movdqu %0, %%xmm7" : : "m"(*data)); break;
710 #ifdef CONFIG_X86_64
711 case 8: asm("movdqu %0, %%xmm8" : : "m"(*data)); break;
712 case 9: asm("movdqu %0, %%xmm9" : : "m"(*data)); break;
713 case 10: asm("movdqu %0, %%xmm10" : : "m"(*data)); break;
714 case 11: asm("movdqu %0, %%xmm11" : : "m"(*data)); break;
715 case 12: asm("movdqu %0, %%xmm12" : : "m"(*data)); break;
716 case 13: asm("movdqu %0, %%xmm13" : : "m"(*data)); break;
717 case 14: asm("movdqu %0, %%xmm14" : : "m"(*data)); break;
718 case 15: asm("movdqu %0, %%xmm15" : : "m"(*data)); break;
719 #endif
720 default: BUG();
721 }
722 ctxt->ops->put_fpu(ctxt);
723 }
724
725 static void decode_register_operand(struct x86_emulate_ctxt *ctxt,
726 struct operand *op,
727 struct decode_cache *c,
728 int inhibit_bytereg)
729 {
730 unsigned reg = c->modrm_reg;
731 int highbyte_regs = c->rex_prefix == 0;
732
733 if (!(c->d & ModRM))
734 reg = (c->b & 7) | ((c->rex_prefix & 1) << 3);
735
736 if (c->d & Sse) {
737 op->type = OP_XMM;
738 op->bytes = 16;
739 op->addr.xmm = reg;
740 read_sse_reg(ctxt, &op->vec_val, reg);
741 return;
742 }
743
744 op->type = OP_REG;
745 if ((c->d & ByteOp) && !inhibit_bytereg) {
746 op->addr.reg = decode_register(reg, c->regs, highbyte_regs);
747 op->bytes = 1;
748 } else {
749 op->addr.reg = decode_register(reg, c->regs, 0);
750 op->bytes = c->op_bytes;
751 }
752 fetch_register_operand(op);
753 op->orig_val = op->val;
754 }
755
756 static int decode_modrm(struct x86_emulate_ctxt *ctxt,
757 struct x86_emulate_ops *ops,
758 struct operand *op)
759 {
760 struct decode_cache *c = &ctxt->decode;
761 u8 sib;
762 int index_reg = 0, base_reg = 0, scale;
763 int rc = X86EMUL_CONTINUE;
764 ulong modrm_ea = 0;
765
766 if (c->rex_prefix) {
767 c->modrm_reg = (c->rex_prefix & 4) << 1; /* REX.R */
768 index_reg = (c->rex_prefix & 2) << 2; /* REX.X */
769 c->modrm_rm = base_reg = (c->rex_prefix & 1) << 3; /* REG.B */
770 }
771
772 c->modrm = insn_fetch(u8, 1, c->eip);
773 c->modrm_mod |= (c->modrm & 0xc0) >> 6;
774 c->modrm_reg |= (c->modrm & 0x38) >> 3;
775 c->modrm_rm |= (c->modrm & 0x07);
776 c->modrm_seg = VCPU_SREG_DS;
777
778 if (c->modrm_mod == 3) {
779 op->type = OP_REG;
780 op->bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
781 op->addr.reg = decode_register(c->modrm_rm,
782 c->regs, c->d & ByteOp);
783 if (c->d & Sse) {
784 op->type = OP_XMM;
785 op->bytes = 16;
786 op->addr.xmm = c->modrm_rm;
787 read_sse_reg(ctxt, &op->vec_val, c->modrm_rm);
788 return rc;
789 }
790 fetch_register_operand(op);
791 return rc;
792 }
793
794 op->type = OP_MEM;
795
796 if (c->ad_bytes == 2) {
797 unsigned bx = c->regs[VCPU_REGS_RBX];
798 unsigned bp = c->regs[VCPU_REGS_RBP];
799 unsigned si = c->regs[VCPU_REGS_RSI];
800 unsigned di = c->regs[VCPU_REGS_RDI];
801
802 /* 16-bit ModR/M decode. */
803 switch (c->modrm_mod) {
804 case 0:
805 if (c->modrm_rm == 6)
806 modrm_ea += insn_fetch(u16, 2, c->eip);
807 break;
808 case 1:
809 modrm_ea += insn_fetch(s8, 1, c->eip);
810 break;
811 case 2:
812 modrm_ea += insn_fetch(u16, 2, c->eip);
813 break;
814 }
815 switch (c->modrm_rm) {
816 case 0:
817 modrm_ea += bx + si;
818 break;
819 case 1:
820 modrm_ea += bx + di;
821 break;
822 case 2:
823 modrm_ea += bp + si;
824 break;
825 case 3:
826 modrm_ea += bp + di;
827 break;
828 case 4:
829 modrm_ea += si;
830 break;
831 case 5:
832 modrm_ea += di;
833 break;
834 case 6:
835 if (c->modrm_mod != 0)
836 modrm_ea += bp;
837 break;
838 case 7:
839 modrm_ea += bx;
840 break;
841 }
842 if (c->modrm_rm == 2 || c->modrm_rm == 3 ||
843 (c->modrm_rm == 6 && c->modrm_mod != 0))
844 c->modrm_seg = VCPU_SREG_SS;
845 modrm_ea = (u16)modrm_ea;
846 } else {
847 /* 32/64-bit ModR/M decode. */
848 if ((c->modrm_rm & 7) == 4) {
849 sib = insn_fetch(u8, 1, c->eip);
850 index_reg |= (sib >> 3) & 7;
851 base_reg |= sib & 7;
852 scale = sib >> 6;
853
854 if ((base_reg & 7) == 5 && c->modrm_mod == 0)
855 modrm_ea += insn_fetch(s32, 4, c->eip);
856 else
857 modrm_ea += c->regs[base_reg];
858 if (index_reg != 4)
859 modrm_ea += c->regs[index_reg] << scale;
860 } else if ((c->modrm_rm & 7) == 5 && c->modrm_mod == 0) {
861 if (ctxt->mode == X86EMUL_MODE_PROT64)
862 c->rip_relative = 1;
863 } else
864 modrm_ea += c->regs[c->modrm_rm];
865 switch (c->modrm_mod) {
866 case 0:
867 if (c->modrm_rm == 5)
868 modrm_ea += insn_fetch(s32, 4, c->eip);
869 break;
870 case 1:
871 modrm_ea += insn_fetch(s8, 1, c->eip);
872 break;
873 case 2:
874 modrm_ea += insn_fetch(s32, 4, c->eip);
875 break;
876 }
877 }
878 op->addr.mem.ea = modrm_ea;
879 done:
880 return rc;
881 }
882
883 static int decode_abs(struct x86_emulate_ctxt *ctxt,
884 struct x86_emulate_ops *ops,
885 struct operand *op)
886 {
887 struct decode_cache *c = &ctxt->decode;
888 int rc = X86EMUL_CONTINUE;
889
890 op->type = OP_MEM;
891 switch (c->ad_bytes) {
892 case 2:
893 op->addr.mem.ea = insn_fetch(u16, 2, c->eip);
894 break;
895 case 4:
896 op->addr.mem.ea = insn_fetch(u32, 4, c->eip);
897 break;
898 case 8:
899 op->addr.mem.ea = insn_fetch(u64, 8, c->eip);
900 break;
901 }
902 done:
903 return rc;
904 }
905
906 static void fetch_bit_operand(struct decode_cache *c)
907 {
908 long sv = 0, mask;
909
910 if (c->dst.type == OP_MEM && c->src.type == OP_REG) {
911 mask = ~(c->dst.bytes * 8 - 1);
912
913 if (c->src.bytes == 2)
914 sv = (s16)c->src.val & (s16)mask;
915 else if (c->src.bytes == 4)
916 sv = (s32)c->src.val & (s32)mask;
917
918 c->dst.addr.mem.ea += (sv >> 3);
919 }
920
921 /* only subword offset */
922 c->src.val &= (c->dst.bytes << 3) - 1;
923 }
924
925 static int read_emulated(struct x86_emulate_ctxt *ctxt,
926 struct x86_emulate_ops *ops,
927 unsigned long addr, void *dest, unsigned size)
928 {
929 int rc;
930 struct read_cache *mc = &ctxt->decode.mem_read;
931
932 while (size) {
933 int n = min(size, 8u);
934 size -= n;
935 if (mc->pos < mc->end)
936 goto read_cached;
937
938 rc = ops->read_emulated(addr, mc->data + mc->end, n,
939 &ctxt->exception, ctxt->vcpu);
940 if (rc != X86EMUL_CONTINUE)
941 return rc;
942 mc->end += n;
943
944 read_cached:
945 memcpy(dest, mc->data + mc->pos, n);
946 mc->pos += n;
947 dest += n;
948 addr += n;
949 }
950 return X86EMUL_CONTINUE;
951 }
952
953 static int pio_in_emulated(struct x86_emulate_ctxt *ctxt,
954 struct x86_emulate_ops *ops,
955 unsigned int size, unsigned short port,
956 void *dest)
957 {
958 struct read_cache *rc = &ctxt->decode.io_read;
959
960 if (rc->pos == rc->end) { /* refill pio read ahead */
961 struct decode_cache *c = &ctxt->decode;
962 unsigned int in_page, n;
963 unsigned int count = c->rep_prefix ?
964 address_mask(c, c->regs[VCPU_REGS_RCX]) : 1;
965 in_page = (ctxt->eflags & EFLG_DF) ?
966 offset_in_page(c->regs[VCPU_REGS_RDI]) :
967 PAGE_SIZE - offset_in_page(c->regs[VCPU_REGS_RDI]);
968 n = min(min(in_page, (unsigned int)sizeof(rc->data)) / size,
969 count);
970 if (n == 0)
971 n = 1;
972 rc->pos = rc->end = 0;
973 if (!ops->pio_in_emulated(size, port, rc->data, n, ctxt->vcpu))
974 return 0;
975 rc->end = n * size;
976 }
977
978 memcpy(dest, rc->data + rc->pos, size);
979 rc->pos += size;
980 return 1;
981 }
982
983 static u32 desc_limit_scaled(struct desc_struct *desc)
984 {
985 u32 limit = get_desc_limit(desc);
986
987 return desc->g ? (limit << 12) | 0xfff : limit;
988 }
989
990 static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
991 struct x86_emulate_ops *ops,
992 u16 selector, struct desc_ptr *dt)
993 {
994 if (selector & 1 << 2) {
995 struct desc_struct desc;
996 memset (dt, 0, sizeof *dt);
997 if (!ops->get_cached_descriptor(&desc, NULL, VCPU_SREG_LDTR,
998 ctxt->vcpu))
999 return;
1000
1001 dt->size = desc_limit_scaled(&desc); /* what if limit > 65535? */
1002 dt->address = get_desc_base(&desc);
1003 } else
1004 ops->get_gdt(dt, ctxt->vcpu);
1005 }
1006
1007 /* allowed just for 8 bytes segments */
1008 static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1009 struct x86_emulate_ops *ops,
1010 u16 selector, struct desc_struct *desc)
1011 {
1012 struct desc_ptr dt;
1013 u16 index = selector >> 3;
1014 int ret;
1015 ulong addr;
1016
1017 get_descriptor_table_ptr(ctxt, ops, selector, &dt);
1018
1019 if (dt.size < index * 8 + 7)
1020 return emulate_gp(ctxt, selector & 0xfffc);
1021 addr = dt.address + index * 8;
1022 ret = ops->read_std(addr, desc, sizeof *desc, ctxt->vcpu,
1023 &ctxt->exception);
1024
1025 return ret;
1026 }
1027
1028 /* allowed just for 8 bytes segments */
1029 static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1030 struct x86_emulate_ops *ops,
1031 u16 selector, struct desc_struct *desc)
1032 {
1033 struct desc_ptr dt;
1034 u16 index = selector >> 3;
1035 ulong addr;
1036 int ret;
1037
1038 get_descriptor_table_ptr(ctxt, ops, selector, &dt);
1039
1040 if (dt.size < index * 8 + 7)
1041 return emulate_gp(ctxt, selector & 0xfffc);
1042
1043 addr = dt.address + index * 8;
1044 ret = ops->write_std(addr, desc, sizeof *desc, ctxt->vcpu,
1045 &ctxt->exception);
1046
1047 return ret;
1048 }
1049
1050 /* Does not support long mode */
1051 static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
1052 struct x86_emulate_ops *ops,
1053 u16 selector, int seg)
1054 {
1055 struct desc_struct seg_desc;
1056 u8 dpl, rpl, cpl;
1057 unsigned err_vec = GP_VECTOR;
1058 u32 err_code = 0;
1059 bool null_selector = !(selector & ~0x3); /* 0000-0003 are null */
1060 int ret;
1061
1062 memset(&seg_desc, 0, sizeof seg_desc);
1063
1064 if ((seg <= VCPU_SREG_GS && ctxt->mode == X86EMUL_MODE_VM86)
1065 || ctxt->mode == X86EMUL_MODE_REAL) {
1066 /* set real mode segment descriptor */
1067 set_desc_base(&seg_desc, selector << 4);
1068 set_desc_limit(&seg_desc, 0xffff);
1069 seg_desc.type = 3;
1070 seg_desc.p = 1;
1071 seg_desc.s = 1;
1072 goto load;
1073 }
1074
1075 /* NULL selector is not valid for TR, CS and SS */
1076 if ((seg == VCPU_SREG_CS || seg == VCPU_SREG_SS || seg == VCPU_SREG_TR)
1077 && null_selector)
1078 goto exception;
1079
1080 /* TR should be in GDT only */
1081 if (seg == VCPU_SREG_TR && (selector & (1 << 2)))
1082 goto exception;
1083
1084 if (null_selector) /* for NULL selector skip all following checks */
1085 goto load;
1086
1087 ret = read_segment_descriptor(ctxt, ops, selector, &seg_desc);
1088 if (ret != X86EMUL_CONTINUE)
1089 return ret;
1090
1091 err_code = selector & 0xfffc;
1092 err_vec = GP_VECTOR;
1093
1094 /* can't load system descriptor into segment selecor */
1095 if (seg <= VCPU_SREG_GS && !seg_desc.s)
1096 goto exception;
1097
1098 if (!seg_desc.p) {
1099 err_vec = (seg == VCPU_SREG_SS) ? SS_VECTOR : NP_VECTOR;
1100 goto exception;
1101 }
1102
1103 rpl = selector & 3;
1104 dpl = seg_desc.dpl;
1105 cpl = ops->cpl(ctxt->vcpu);
1106
1107 switch (seg) {
1108 case VCPU_SREG_SS:
1109 /*
1110 * segment is not a writable data segment or segment
1111 * selector's RPL != CPL or segment selector's RPL != CPL
1112 */
1113 if (rpl != cpl || (seg_desc.type & 0xa) != 0x2 || dpl != cpl)
1114 goto exception;
1115 break;
1116 case VCPU_SREG_CS:
1117 if (!(seg_desc.type & 8))
1118 goto exception;
1119
1120 if (seg_desc.type & 4) {
1121 /* conforming */
1122 if (dpl > cpl)
1123 goto exception;
1124 } else {
1125 /* nonconforming */
1126 if (rpl > cpl || dpl != cpl)
1127 goto exception;
1128 }
1129 /* CS(RPL) <- CPL */
1130 selector = (selector & 0xfffc) | cpl;
1131 break;
1132 case VCPU_SREG_TR:
1133 if (seg_desc.s || (seg_desc.type != 1 && seg_desc.type != 9))
1134 goto exception;
1135 break;
1136 case VCPU_SREG_LDTR:
1137 if (seg_desc.s || seg_desc.type != 2)
1138 goto exception;
1139 break;
1140 default: /* DS, ES, FS, or GS */
1141 /*
1142 * segment is not a data or readable code segment or
1143 * ((segment is a data or nonconforming code segment)
1144 * and (both RPL and CPL > DPL))
1145 */
1146 if ((seg_desc.type & 0xa) == 0x8 ||
1147 (((seg_desc.type & 0xc) != 0xc) &&
1148 (rpl > dpl && cpl > dpl)))
1149 goto exception;
1150 break;
1151 }
1152
1153 if (seg_desc.s) {
1154 /* mark segment as accessed */
1155 seg_desc.type |= 1;
1156 ret = write_segment_descriptor(ctxt, ops, selector, &seg_desc);
1157 if (ret != X86EMUL_CONTINUE)
1158 return ret;
1159 }
1160 load:
1161 ops->set_segment_selector(selector, seg, ctxt->vcpu);
1162 ops->set_cached_descriptor(&seg_desc, 0, seg, ctxt->vcpu);
1163 return X86EMUL_CONTINUE;
1164 exception:
1165 emulate_exception(ctxt, err_vec, err_code, true);
1166 return X86EMUL_PROPAGATE_FAULT;
1167 }
1168
1169 static void write_register_operand(struct operand *op)
1170 {
1171 /* The 4-byte case *is* correct: in 64-bit mode we zero-extend. */
1172 switch (op->bytes) {
1173 case 1:
1174 *(u8 *)op->addr.reg = (u8)op->val;
1175 break;
1176 case 2:
1177 *(u16 *)op->addr.reg = (u16)op->val;
1178 break;
1179 case 4:
1180 *op->addr.reg = (u32)op->val;
1181 break; /* 64b: zero-extend */
1182 case 8:
1183 *op->addr.reg = op->val;
1184 break;
1185 }
1186 }
1187
1188 static inline int writeback(struct x86_emulate_ctxt *ctxt,
1189 struct x86_emulate_ops *ops)
1190 {
1191 int rc;
1192 struct decode_cache *c = &ctxt->decode;
1193
1194 switch (c->dst.type) {
1195 case OP_REG:
1196 write_register_operand(&c->dst);
1197 break;
1198 case OP_MEM:
1199 if (c->lock_prefix)
1200 rc = ops->cmpxchg_emulated(
1201 linear(ctxt, c->dst.addr.mem),
1202 &c->dst.orig_val,
1203 &c->dst.val,
1204 c->dst.bytes,
1205 &ctxt->exception,
1206 ctxt->vcpu);
1207 else
1208 rc = ops->write_emulated(
1209 linear(ctxt, c->dst.addr.mem),
1210 &c->dst.val,
1211 c->dst.bytes,
1212 &ctxt->exception,
1213 ctxt->vcpu);
1214 if (rc != X86EMUL_CONTINUE)
1215 return rc;
1216 break;
1217 case OP_XMM:
1218 write_sse_reg(ctxt, &c->dst.vec_val, c->dst.addr.xmm);
1219 break;
1220 case OP_NONE:
1221 /* no writeback */
1222 break;
1223 default:
1224 break;
1225 }
1226 return X86EMUL_CONTINUE;
1227 }
1228
1229 static inline void emulate_push(struct x86_emulate_ctxt *ctxt,
1230 struct x86_emulate_ops *ops)
1231 {
1232 struct decode_cache *c = &ctxt->decode;
1233
1234 c->dst.type = OP_MEM;
1235 c->dst.bytes = c->op_bytes;
1236 c->dst.val = c->src.val;
1237 register_address_increment(c, &c->regs[VCPU_REGS_RSP], -c->op_bytes);
1238 c->dst.addr.mem.ea = register_address(c, c->regs[VCPU_REGS_RSP]);
1239 c->dst.addr.mem.seg = VCPU_SREG_SS;
1240 }
1241
1242 static int emulate_pop(struct x86_emulate_ctxt *ctxt,
1243 struct x86_emulate_ops *ops,
1244 void *dest, int len)
1245 {
1246 struct decode_cache *c = &ctxt->decode;
1247 int rc;
1248 struct segmented_address addr;
1249
1250 addr.ea = register_address(c, c->regs[VCPU_REGS_RSP]);
1251 addr.seg = VCPU_SREG_SS;
1252 rc = read_emulated(ctxt, ops, linear(ctxt, addr), dest, len);
1253 if (rc != X86EMUL_CONTINUE)
1254 return rc;
1255
1256 register_address_increment(c, &c->regs[VCPU_REGS_RSP], len);
1257 return rc;
1258 }
1259
1260 static int emulate_popf(struct x86_emulate_ctxt *ctxt,
1261 struct x86_emulate_ops *ops,
1262 void *dest, int len)
1263 {
1264 int rc;
1265 unsigned long val, change_mask;
1266 int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
1267 int cpl = ops->cpl(ctxt->vcpu);
1268
1269 rc = emulate_pop(ctxt, ops, &val, len);
1270 if (rc != X86EMUL_CONTINUE)
1271 return rc;
1272
1273 change_mask = EFLG_CF | EFLG_PF | EFLG_AF | EFLG_ZF | EFLG_SF | EFLG_OF
1274 | EFLG_TF | EFLG_DF | EFLG_NT | EFLG_RF | EFLG_AC | EFLG_ID;
1275
1276 switch(ctxt->mode) {
1277 case X86EMUL_MODE_PROT64:
1278 case X86EMUL_MODE_PROT32:
1279 case X86EMUL_MODE_PROT16:
1280 if (cpl == 0)
1281 change_mask |= EFLG_IOPL;
1282 if (cpl <= iopl)
1283 change_mask |= EFLG_IF;
1284 break;
1285 case X86EMUL_MODE_VM86:
1286 if (iopl < 3)
1287 return emulate_gp(ctxt, 0);
1288 change_mask |= EFLG_IF;
1289 break;
1290 default: /* real mode */
1291 change_mask |= (EFLG_IOPL | EFLG_IF);
1292 break;
1293 }
1294
1295 *(unsigned long *)dest =
1296 (ctxt->eflags & ~change_mask) | (val & change_mask);
1297
1298 return rc;
1299 }
1300
1301 static void emulate_push_sreg(struct x86_emulate_ctxt *ctxt,
1302 struct x86_emulate_ops *ops, int seg)
1303 {
1304 struct decode_cache *c = &ctxt->decode;
1305
1306 c->src.val = ops->get_segment_selector(seg, ctxt->vcpu);
1307
1308 emulate_push(ctxt, ops);
1309 }
1310
1311 static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt,
1312 struct x86_emulate_ops *ops, int seg)
1313 {
1314 struct decode_cache *c = &ctxt->decode;
1315 unsigned long selector;
1316 int rc;
1317
1318 rc = emulate_pop(ctxt, ops, &selector, c->op_bytes);
1319 if (rc != X86EMUL_CONTINUE)
1320 return rc;
1321
1322 rc = load_segment_descriptor(ctxt, ops, (u16)selector, seg);
1323 return rc;
1324 }
1325
1326 static int emulate_pusha(struct x86_emulate_ctxt *ctxt,
1327 struct x86_emulate_ops *ops)
1328 {
1329 struct decode_cache *c = &ctxt->decode;
1330 unsigned long old_esp = c->regs[VCPU_REGS_RSP];
1331 int rc = X86EMUL_CONTINUE;
1332 int reg = VCPU_REGS_RAX;
1333
1334 while (reg <= VCPU_REGS_RDI) {
1335 (reg == VCPU_REGS_RSP) ?
1336 (c->src.val = old_esp) : (c->src.val = c->regs[reg]);
1337
1338 emulate_push(ctxt, ops);
1339
1340 rc = writeback(ctxt, ops);
1341 if (rc != X86EMUL_CONTINUE)
1342 return rc;
1343
1344 ++reg;
1345 }
1346
1347 /* Disable writeback. */
1348 c->dst.type = OP_NONE;
1349
1350 return rc;
1351 }
1352
1353 static int emulate_popa(struct x86_emulate_ctxt *ctxt,
1354 struct x86_emulate_ops *ops)
1355 {
1356 struct decode_cache *c = &ctxt->decode;
1357 int rc = X86EMUL_CONTINUE;
1358 int reg = VCPU_REGS_RDI;
1359
1360 while (reg >= VCPU_REGS_RAX) {
1361 if (reg == VCPU_REGS_RSP) {
1362 register_address_increment(c, &c->regs[VCPU_REGS_RSP],
1363 c->op_bytes);
1364 --reg;
1365 }
1366
1367 rc = emulate_pop(ctxt, ops, &c->regs[reg], c->op_bytes);
1368 if (rc != X86EMUL_CONTINUE)
1369 break;
1370 --reg;
1371 }
1372 return rc;
1373 }
1374
1375 int emulate_int_real(struct x86_emulate_ctxt *ctxt,
1376 struct x86_emulate_ops *ops, int irq)
1377 {
1378 struct decode_cache *c = &ctxt->decode;
1379 int rc;
1380 struct desc_ptr dt;
1381 gva_t cs_addr;
1382 gva_t eip_addr;
1383 u16 cs, eip;
1384
1385 /* TODO: Add limit checks */
1386 c->src.val = ctxt->eflags;
1387 emulate_push(ctxt, ops);
1388 rc = writeback(ctxt, ops);
1389 if (rc != X86EMUL_CONTINUE)
1390 return rc;
1391
1392 ctxt->eflags &= ~(EFLG_IF | EFLG_TF | EFLG_AC);
1393
1394 c->src.val = ops->get_segment_selector(VCPU_SREG_CS, ctxt->vcpu);
1395 emulate_push(ctxt, ops);
1396 rc = writeback(ctxt, ops);
1397 if (rc != X86EMUL_CONTINUE)
1398 return rc;
1399
1400 c->src.val = c->eip;
1401 emulate_push(ctxt, ops);
1402 rc = writeback(ctxt, ops);
1403 if (rc != X86EMUL_CONTINUE)
1404 return rc;
1405
1406 c->dst.type = OP_NONE;
1407
1408 ops->get_idt(&dt, ctxt->vcpu);
1409
1410 eip_addr = dt.address + (irq << 2);
1411 cs_addr = dt.address + (irq << 2) + 2;
1412
1413 rc = ops->read_std(cs_addr, &cs, 2, ctxt->vcpu, &ctxt->exception);
1414 if (rc != X86EMUL_CONTINUE)
1415 return rc;
1416
1417 rc = ops->read_std(eip_addr, &eip, 2, ctxt->vcpu, &ctxt->exception);
1418 if (rc != X86EMUL_CONTINUE)
1419 return rc;
1420
1421 rc = load_segment_descriptor(ctxt, ops, cs, VCPU_SREG_CS);
1422 if (rc != X86EMUL_CONTINUE)
1423 return rc;
1424
1425 c->eip = eip;
1426
1427 return rc;
1428 }
1429
1430 static int emulate_int(struct x86_emulate_ctxt *ctxt,
1431 struct x86_emulate_ops *ops, int irq)
1432 {
1433 switch(ctxt->mode) {
1434 case X86EMUL_MODE_REAL:
1435 return emulate_int_real(ctxt, ops, irq);
1436 case X86EMUL_MODE_VM86:
1437 case X86EMUL_MODE_PROT16:
1438 case X86EMUL_MODE_PROT32:
1439 case X86EMUL_MODE_PROT64:
1440 default:
1441 /* Protected mode interrupts unimplemented yet */
1442 return X86EMUL_UNHANDLEABLE;
1443 }
1444 }
1445
1446 static int emulate_iret_real(struct x86_emulate_ctxt *ctxt,
1447 struct x86_emulate_ops *ops)
1448 {
1449 struct decode_cache *c = &ctxt->decode;
1450 int rc = X86EMUL_CONTINUE;
1451 unsigned long temp_eip = 0;
1452 unsigned long temp_eflags = 0;
1453 unsigned long cs = 0;
1454 unsigned long mask = EFLG_CF | EFLG_PF | EFLG_AF | EFLG_ZF | EFLG_SF | EFLG_TF |
1455 EFLG_IF | EFLG_DF | EFLG_OF | EFLG_IOPL | EFLG_NT | EFLG_RF |
1456 EFLG_AC | EFLG_ID | (1 << 1); /* Last one is the reserved bit */
1457 unsigned long vm86_mask = EFLG_VM | EFLG_VIF | EFLG_VIP;
1458
1459 /* TODO: Add stack limit check */
1460
1461 rc = emulate_pop(ctxt, ops, &temp_eip, c->op_bytes);
1462
1463 if (rc != X86EMUL_CONTINUE)
1464 return rc;
1465
1466 if (temp_eip & ~0xffff)
1467 return emulate_gp(ctxt, 0);
1468
1469 rc = emulate_pop(ctxt, ops, &cs, c->op_bytes);
1470
1471 if (rc != X86EMUL_CONTINUE)
1472 return rc;
1473
1474 rc = emulate_pop(ctxt, ops, &temp_eflags, c->op_bytes);
1475
1476 if (rc != X86EMUL_CONTINUE)
1477 return rc;
1478
1479 rc = load_segment_descriptor(ctxt, ops, (u16)cs, VCPU_SREG_CS);
1480
1481 if (rc != X86EMUL_CONTINUE)
1482 return rc;
1483
1484 c->eip = temp_eip;
1485
1486
1487 if (c->op_bytes == 4)
1488 ctxt->eflags = ((temp_eflags & mask) | (ctxt->eflags & vm86_mask));
1489 else if (c->op_bytes == 2) {
1490 ctxt->eflags &= ~0xffff;
1491 ctxt->eflags |= temp_eflags;
1492 }
1493
1494 ctxt->eflags &= ~EFLG_RESERVED_ZEROS_MASK; /* Clear reserved zeros */
1495 ctxt->eflags |= EFLG_RESERVED_ONE_MASK;
1496
1497 return rc;
1498 }
1499
1500 static inline int emulate_iret(struct x86_emulate_ctxt *ctxt,
1501 struct x86_emulate_ops* ops)
1502 {
1503 switch(ctxt->mode) {
1504 case X86EMUL_MODE_REAL:
1505 return emulate_iret_real(ctxt, ops);
1506 case X86EMUL_MODE_VM86:
1507 case X86EMUL_MODE_PROT16:
1508 case X86EMUL_MODE_PROT32:
1509 case X86EMUL_MODE_PROT64:
1510 default:
1511 /* iret from protected mode unimplemented yet */
1512 return X86EMUL_UNHANDLEABLE;
1513 }
1514 }
1515
1516 static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt,
1517 struct x86_emulate_ops *ops)
1518 {
1519 struct decode_cache *c = &ctxt->decode;
1520
1521 return emulate_pop(ctxt, ops, &c->dst.val, c->dst.bytes);
1522 }
1523
1524 static inline void emulate_grp2(struct x86_emulate_ctxt *ctxt)
1525 {
1526 struct decode_cache *c = &ctxt->decode;
1527 switch (c->modrm_reg) {
1528 case 0: /* rol */
1529 emulate_2op_SrcB("rol", c->src, c->dst, ctxt->eflags);
1530 break;
1531 case 1: /* ror */
1532 emulate_2op_SrcB("ror", c->src, c->dst, ctxt->eflags);
1533 break;
1534 case 2: /* rcl */
1535 emulate_2op_SrcB("rcl", c->src, c->dst, ctxt->eflags);
1536 break;
1537 case 3: /* rcr */
1538 emulate_2op_SrcB("rcr", c->src, c->dst, ctxt->eflags);
1539 break;
1540 case 4: /* sal/shl */
1541 case 6: /* sal/shl */
1542 emulate_2op_SrcB("sal", c->src, c->dst, ctxt->eflags);
1543 break;
1544 case 5: /* shr */
1545 emulate_2op_SrcB("shr", c->src, c->dst, ctxt->eflags);
1546 break;
1547 case 7: /* sar */
1548 emulate_2op_SrcB("sar", c->src, c->dst, ctxt->eflags);
1549 break;
1550 }
1551 }
1552
1553 static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt,
1554 struct x86_emulate_ops *ops)
1555 {
1556 struct decode_cache *c = &ctxt->decode;
1557 unsigned long *rax = &c->regs[VCPU_REGS_RAX];
1558 unsigned long *rdx = &c->regs[VCPU_REGS_RDX];
1559 u8 de = 0;
1560
1561 switch (c->modrm_reg) {
1562 case 0 ... 1: /* test */
1563 emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
1564 break;
1565 case 2: /* not */
1566 c->dst.val = ~c->dst.val;
1567 break;
1568 case 3: /* neg */
1569 emulate_1op("neg", c->dst, ctxt->eflags);
1570 break;
1571 case 4: /* mul */
1572 emulate_1op_rax_rdx("mul", c->src, *rax, *rdx, ctxt->eflags);
1573 break;
1574 case 5: /* imul */
1575 emulate_1op_rax_rdx("imul", c->src, *rax, *rdx, ctxt->eflags);
1576 break;
1577 case 6: /* div */
1578 emulate_1op_rax_rdx_ex("div", c->src, *rax, *rdx,
1579 ctxt->eflags, de);
1580 break;
1581 case 7: /* idiv */
1582 emulate_1op_rax_rdx_ex("idiv", c->src, *rax, *rdx,
1583 ctxt->eflags, de);
1584 break;
1585 default:
1586 return X86EMUL_UNHANDLEABLE;
1587 }
1588 if (de)
1589 return emulate_de(ctxt);
1590 return X86EMUL_CONTINUE;
1591 }
1592
1593 static inline int emulate_grp45(struct x86_emulate_ctxt *ctxt,
1594 struct x86_emulate_ops *ops)
1595 {
1596 struct decode_cache *c = &ctxt->decode;
1597
1598 switch (c->modrm_reg) {
1599 case 0: /* inc */
1600 emulate_1op("inc", c->dst, ctxt->eflags);
1601 break;
1602 case 1: /* dec */
1603 emulate_1op("dec", c->dst, ctxt->eflags);
1604 break;
1605 case 2: /* call near abs */ {
1606 long int old_eip;
1607 old_eip = c->eip;
1608 c->eip = c->src.val;
1609 c->src.val = old_eip;
1610 emulate_push(ctxt, ops);
1611 break;
1612 }
1613 case 4: /* jmp abs */
1614 c->eip = c->src.val;
1615 break;
1616 case 6: /* push */
1617 emulate_push(ctxt, ops);
1618 break;
1619 }
1620 return X86EMUL_CONTINUE;
1621 }
1622
1623 static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
1624 struct x86_emulate_ops *ops)
1625 {
1626 struct decode_cache *c = &ctxt->decode;
1627 u64 old = c->dst.orig_val64;
1628
1629 if (((u32) (old >> 0) != (u32) c->regs[VCPU_REGS_RAX]) ||
1630 ((u32) (old >> 32) != (u32) c->regs[VCPU_REGS_RDX])) {
1631 c->regs[VCPU_REGS_RAX] = (u32) (old >> 0);
1632 c->regs[VCPU_REGS_RDX] = (u32) (old >> 32);
1633 ctxt->eflags &= ~EFLG_ZF;
1634 } else {
1635 c->dst.val64 = ((u64)c->regs[VCPU_REGS_RCX] << 32) |
1636 (u32) c->regs[VCPU_REGS_RBX];
1637
1638 ctxt->eflags |= EFLG_ZF;
1639 }
1640 return X86EMUL_CONTINUE;
1641 }
1642
1643 static int emulate_ret_far(struct x86_emulate_ctxt *ctxt,
1644 struct x86_emulate_ops *ops)
1645 {
1646 struct decode_cache *c = &ctxt->decode;
1647 int rc;
1648 unsigned long cs;
1649
1650 rc = emulate_pop(ctxt, ops, &c->eip, c->op_bytes);
1651 if (rc != X86EMUL_CONTINUE)
1652 return rc;
1653 if (c->op_bytes == 4)
1654 c->eip = (u32)c->eip;
1655 rc = emulate_pop(ctxt, ops, &cs, c->op_bytes);
1656 if (rc != X86EMUL_CONTINUE)
1657 return rc;
1658 rc = load_segment_descriptor(ctxt, ops, (u16)cs, VCPU_SREG_CS);
1659 return rc;
1660 }
1661
1662 static int emulate_load_segment(struct x86_emulate_ctxt *ctxt,
1663 struct x86_emulate_ops *ops, int seg)
1664 {
1665 struct decode_cache *c = &ctxt->decode;
1666 unsigned short sel;
1667 int rc;
1668
1669 memcpy(&sel, c->src.valptr + c->op_bytes, 2);
1670
1671 rc = load_segment_descriptor(ctxt, ops, sel, seg);
1672 if (rc != X86EMUL_CONTINUE)
1673 return rc;
1674
1675 c->dst.val = c->src.val;
1676 return rc;
1677 }
1678
1679 static inline void
1680 setup_syscalls_segments(struct x86_emulate_ctxt *ctxt,
1681 struct x86_emulate_ops *ops, struct desc_struct *cs,
1682 struct desc_struct *ss)
1683 {
1684 memset(cs, 0, sizeof(struct desc_struct));
1685 ops->get_cached_descriptor(cs, NULL, VCPU_SREG_CS, ctxt->vcpu);
1686 memset(ss, 0, sizeof(struct desc_struct));
1687
1688 cs->l = 0; /* will be adjusted later */
1689 set_desc_base(cs, 0); /* flat segment */
1690 cs->g = 1; /* 4kb granularity */
1691 set_desc_limit(cs, 0xfffff); /* 4GB limit */
1692 cs->type = 0x0b; /* Read, Execute, Accessed */
1693 cs->s = 1;
1694 cs->dpl = 0; /* will be adjusted later */
1695 cs->p = 1;
1696 cs->d = 1;
1697
1698 set_desc_base(ss, 0); /* flat segment */
1699 set_desc_limit(ss, 0xfffff); /* 4GB limit */
1700 ss->g = 1; /* 4kb granularity */
1701 ss->s = 1;
1702 ss->type = 0x03; /* Read/Write, Accessed */
1703 ss->d = 1; /* 32bit stack segment */
1704 ss->dpl = 0;
1705 ss->p = 1;
1706 }
1707
1708 static int
1709 emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
1710 {
1711 struct decode_cache *c = &ctxt->decode;
1712 struct desc_struct cs, ss;
1713 u64 msr_data;
1714 u16 cs_sel, ss_sel;
1715
1716 /* syscall is not available in real mode */
1717 if (ctxt->mode == X86EMUL_MODE_REAL ||
1718 ctxt->mode == X86EMUL_MODE_VM86)
1719 return emulate_ud(ctxt);
1720
1721 setup_syscalls_segments(ctxt, ops, &cs, &ss);
1722
1723 ops->get_msr(ctxt->vcpu, MSR_STAR, &msr_data);
1724 msr_data >>= 32;
1725 cs_sel = (u16)(msr_data & 0xfffc);
1726 ss_sel = (u16)(msr_data + 8);
1727
1728 if (is_long_mode(ctxt->vcpu)) {
1729 cs.d = 0;
1730 cs.l = 1;
1731 }
1732 ops->set_cached_descriptor(&cs, 0, VCPU_SREG_CS, ctxt->vcpu);
1733 ops->set_segment_selector(cs_sel, VCPU_SREG_CS, ctxt->vcpu);
1734 ops->set_cached_descriptor(&ss, 0, VCPU_SREG_SS, ctxt->vcpu);
1735 ops->set_segment_selector(ss_sel, VCPU_SREG_SS, ctxt->vcpu);
1736
1737 c->regs[VCPU_REGS_RCX] = c->eip;
1738 if (is_long_mode(ctxt->vcpu)) {
1739 #ifdef CONFIG_X86_64
1740 c->regs[VCPU_REGS_R11] = ctxt->eflags & ~EFLG_RF;
1741
1742 ops->get_msr(ctxt->vcpu,
1743 ctxt->mode == X86EMUL_MODE_PROT64 ?
1744 MSR_LSTAR : MSR_CSTAR, &msr_data);
1745 c->eip = msr_data;
1746
1747 ops->get_msr(ctxt->vcpu, MSR_SYSCALL_MASK, &msr_data);
1748 ctxt->eflags &= ~(msr_data | EFLG_RF);
1749 #endif
1750 } else {
1751 /* legacy mode */
1752 ops->get_msr(ctxt->vcpu, MSR_STAR, &msr_data);
1753 c->eip = (u32)msr_data;
1754
1755 ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
1756 }
1757
1758 return X86EMUL_CONTINUE;
1759 }
1760
1761 static int
1762 emulate_sysenter(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
1763 {
1764 struct decode_cache *c = &ctxt->decode;
1765 struct desc_struct cs, ss;
1766 u64 msr_data;
1767 u16 cs_sel, ss_sel;
1768
1769 /* inject #GP if in real mode */
1770 if (ctxt->mode == X86EMUL_MODE_REAL)
1771 return emulate_gp(ctxt, 0);
1772
1773 /* XXX sysenter/sysexit have not been tested in 64bit mode.
1774 * Therefore, we inject an #UD.
1775 */
1776 if (ctxt->mode == X86EMUL_MODE_PROT64)
1777 return emulate_ud(ctxt);
1778
1779 setup_syscalls_segments(ctxt, ops, &cs, &ss);
1780
1781 ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_CS, &msr_data);
1782 switch (ctxt->mode) {
1783 case X86EMUL_MODE_PROT32:
1784 if ((msr_data & 0xfffc) == 0x0)
1785 return emulate_gp(ctxt, 0);
1786 break;
1787 case X86EMUL_MODE_PROT64:
1788 if (msr_data == 0x0)
1789 return emulate_gp(ctxt, 0);
1790 break;
1791 }
1792
1793 ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
1794 cs_sel = (u16)msr_data;
1795 cs_sel &= ~SELECTOR_RPL_MASK;
1796 ss_sel = cs_sel + 8;
1797 ss_sel &= ~SELECTOR_RPL_MASK;
1798 if (ctxt->mode == X86EMUL_MODE_PROT64
1799 || is_long_mode(ctxt->vcpu)) {
1800 cs.d = 0;
1801 cs.l = 1;
1802 }
1803
1804 ops->set_cached_descriptor(&cs, 0, VCPU_SREG_CS, ctxt->vcpu);
1805 ops->set_segment_selector(cs_sel, VCPU_SREG_CS, ctxt->vcpu);
1806 ops->set_cached_descriptor(&ss, 0, VCPU_SREG_SS, ctxt->vcpu);
1807 ops->set_segment_selector(ss_sel, VCPU_SREG_SS, ctxt->vcpu);
1808
1809 ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_EIP, &msr_data);
1810 c->eip = msr_data;
1811
1812 ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_ESP, &msr_data);
1813 c->regs[VCPU_REGS_RSP] = msr_data;
1814
1815 return X86EMUL_CONTINUE;
1816 }
1817
1818 static int
1819 emulate_sysexit(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
1820 {
1821 struct decode_cache *c = &ctxt->decode;
1822 struct desc_struct cs, ss;
1823 u64 msr_data;
1824 int usermode;
1825 u16 cs_sel, ss_sel;
1826
1827 /* inject #GP if in real mode or Virtual 8086 mode */
1828 if (ctxt->mode == X86EMUL_MODE_REAL ||
1829 ctxt->mode == X86EMUL_MODE_VM86)
1830 return emulate_gp(ctxt, 0);
1831
1832 setup_syscalls_segments(ctxt, ops, &cs, &ss);
1833
1834 if ((c->rex_prefix & 0x8) != 0x0)
1835 usermode = X86EMUL_MODE_PROT64;
1836 else
1837 usermode = X86EMUL_MODE_PROT32;
1838
1839 cs.dpl = 3;
1840 ss.dpl = 3;
1841 ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_CS, &msr_data);
1842 switch (usermode) {
1843 case X86EMUL_MODE_PROT32:
1844 cs_sel = (u16)(msr_data + 16);
1845 if ((msr_data & 0xfffc) == 0x0)
1846 return emulate_gp(ctxt, 0);
1847 ss_sel = (u16)(msr_data + 24);
1848 break;
1849 case X86EMUL_MODE_PROT64:
1850 cs_sel = (u16)(msr_data + 32);
1851 if (msr_data == 0x0)
1852 return emulate_gp(ctxt, 0);
1853 ss_sel = cs_sel + 8;
1854 cs.d = 0;
1855 cs.l = 1;
1856 break;
1857 }
1858 cs_sel |= SELECTOR_RPL_MASK;
1859 ss_sel |= SELECTOR_RPL_MASK;
1860
1861 ops->set_cached_descriptor(&cs, 0, VCPU_SREG_CS, ctxt->vcpu);
1862 ops->set_segment_selector(cs_sel, VCPU_SREG_CS, ctxt->vcpu);
1863 ops->set_cached_descriptor(&ss, 0, VCPU_SREG_SS, ctxt->vcpu);
1864 ops->set_segment_selector(ss_sel, VCPU_SREG_SS, ctxt->vcpu);
1865
1866 c->eip = c->regs[VCPU_REGS_RDX];
1867 c->regs[VCPU_REGS_RSP] = c->regs[VCPU_REGS_RCX];
1868
1869 return X86EMUL_CONTINUE;
1870 }
1871
1872 static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt,
1873 struct x86_emulate_ops *ops)
1874 {
1875 int iopl;
1876 if (ctxt->mode == X86EMUL_MODE_REAL)
1877 return false;
1878 if (ctxt->mode == X86EMUL_MODE_VM86)
1879 return true;
1880 iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
1881 return ops->cpl(ctxt->vcpu) > iopl;
1882 }
1883
1884 static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
1885 struct x86_emulate_ops *ops,
1886 u16 port, u16 len)
1887 {
1888 struct desc_struct tr_seg;
1889 u32 base3;
1890 int r;
1891 u16 io_bitmap_ptr, perm, bit_idx = port & 0x7;
1892 unsigned mask = (1 << len) - 1;
1893 unsigned long base;
1894
1895 ops->get_cached_descriptor(&tr_seg, &base3, VCPU_SREG_TR, ctxt->vcpu);
1896 if (!tr_seg.p)
1897 return false;
1898 if (desc_limit_scaled(&tr_seg) < 103)
1899 return false;
1900 base = get_desc_base(&tr_seg);
1901 #ifdef CONFIG_X86_64
1902 base |= ((u64)base3) << 32;
1903 #endif
1904 r = ops->read_std(base + 102, &io_bitmap_ptr, 2, ctxt->vcpu, NULL);
1905 if (r != X86EMUL_CONTINUE)
1906 return false;
1907 if (io_bitmap_ptr + port/8 > desc_limit_scaled(&tr_seg))
1908 return false;
1909 r = ops->read_std(base + io_bitmap_ptr + port/8, &perm, 2, ctxt->vcpu,
1910 NULL);
1911 if (r != X86EMUL_CONTINUE)
1912 return false;
1913 if ((perm >> bit_idx) & mask)
1914 return false;
1915 return true;
1916 }
1917
1918 static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
1919 struct x86_emulate_ops *ops,
1920 u16 port, u16 len)
1921 {
1922 if (ctxt->perm_ok)
1923 return true;
1924
1925 if (emulator_bad_iopl(ctxt, ops))
1926 if (!emulator_io_port_access_allowed(ctxt, ops, port, len))
1927 return false;
1928
1929 ctxt->perm_ok = true;
1930
1931 return true;
1932 }
1933
1934 static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt,
1935 struct x86_emulate_ops *ops,
1936 struct tss_segment_16 *tss)
1937 {
1938 struct decode_cache *c = &ctxt->decode;
1939
1940 tss->ip = c->eip;
1941 tss->flag = ctxt->eflags;
1942 tss->ax = c->regs[VCPU_REGS_RAX];
1943 tss->cx = c->regs[VCPU_REGS_RCX];
1944 tss->dx = c->regs[VCPU_REGS_RDX];
1945 tss->bx = c->regs[VCPU_REGS_RBX];
1946 tss->sp = c->regs[VCPU_REGS_RSP];
1947 tss->bp = c->regs[VCPU_REGS_RBP];
1948 tss->si = c->regs[VCPU_REGS_RSI];
1949 tss->di = c->regs[VCPU_REGS_RDI];
1950
1951 tss->es = ops->get_segment_selector(VCPU_SREG_ES, ctxt->vcpu);
1952 tss->cs = ops->get_segment_selector(VCPU_SREG_CS, ctxt->vcpu);
1953 tss->ss = ops->get_segment_selector(VCPU_SREG_SS, ctxt->vcpu);
1954 tss->ds = ops->get_segment_selector(VCPU_SREG_DS, ctxt->vcpu);
1955 tss->ldt = ops->get_segment_selector(VCPU_SREG_LDTR, ctxt->vcpu);
1956 }
1957
1958 static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
1959 struct x86_emulate_ops *ops,
1960 struct tss_segment_16 *tss)
1961 {
1962 struct decode_cache *c = &ctxt->decode;
1963 int ret;
1964
1965 c->eip = tss->ip;
1966 ctxt->eflags = tss->flag | 2;
1967 c->regs[VCPU_REGS_RAX] = tss->ax;
1968 c->regs[VCPU_REGS_RCX] = tss->cx;
1969 c->regs[VCPU_REGS_RDX] = tss->dx;
1970 c->regs[VCPU_REGS_RBX] = tss->bx;
1971 c->regs[VCPU_REGS_RSP] = tss->sp;
1972 c->regs[VCPU_REGS_RBP] = tss->bp;
1973 c->regs[VCPU_REGS_RSI] = tss->si;
1974 c->regs[VCPU_REGS_RDI] = tss->di;
1975
1976 /*
1977 * SDM says that segment selectors are loaded before segment
1978 * descriptors
1979 */
1980 ops->set_segment_selector(tss->ldt, VCPU_SREG_LDTR, ctxt->vcpu);
1981 ops->set_segment_selector(tss->es, VCPU_SREG_ES, ctxt->vcpu);
1982 ops->set_segment_selector(tss->cs, VCPU_SREG_CS, ctxt->vcpu);
1983 ops->set_segment_selector(tss->ss, VCPU_SREG_SS, ctxt->vcpu);
1984 ops->set_segment_selector(tss->ds, VCPU_SREG_DS, ctxt->vcpu);
1985
1986 /*
1987 * Now load segment descriptors. If fault happenes at this stage
1988 * it is handled in a context of new task
1989 */
1990 ret = load_segment_descriptor(ctxt, ops, tss->ldt, VCPU_SREG_LDTR);
1991 if (ret != X86EMUL_CONTINUE)
1992 return ret;
1993 ret = load_segment_descriptor(ctxt, ops, tss->es, VCPU_SREG_ES);
1994 if (ret != X86EMUL_CONTINUE)
1995 return ret;
1996 ret = load_segment_descriptor(ctxt, ops, tss->cs, VCPU_SREG_CS);
1997 if (ret != X86EMUL_CONTINUE)
1998 return ret;
1999 ret = load_segment_descriptor(ctxt, ops, tss->ss, VCPU_SREG_SS);
2000 if (ret != X86EMUL_CONTINUE)
2001 return ret;
2002 ret = load_segment_descriptor(ctxt, ops, tss->ds, VCPU_SREG_DS);
2003 if (ret != X86EMUL_CONTINUE)
2004 return ret;
2005
2006 return X86EMUL_CONTINUE;
2007 }
2008
2009 static int task_switch_16(struct x86_emulate_ctxt *ctxt,
2010 struct x86_emulate_ops *ops,
2011 u16 tss_selector, u16 old_tss_sel,
2012 ulong old_tss_base, struct desc_struct *new_desc)
2013 {
2014 struct tss_segment_16 tss_seg;
2015 int ret;
2016 u32 new_tss_base = get_desc_base(new_desc);
2017
2018 ret = ops->read_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2019 &ctxt->exception);
2020 if (ret != X86EMUL_CONTINUE)
2021 /* FIXME: need to provide precise fault address */
2022 return ret;
2023
2024 save_state_to_tss16(ctxt, ops, &tss_seg);
2025
2026 ret = ops->write_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2027 &ctxt->exception);
2028 if (ret != X86EMUL_CONTINUE)
2029 /* FIXME: need to provide precise fault address */
2030 return ret;
2031
2032 ret = ops->read_std(new_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2033 &ctxt->exception);
2034 if (ret != X86EMUL_CONTINUE)
2035 /* FIXME: need to provide precise fault address */
2036 return ret;
2037
2038 if (old_tss_sel != 0xffff) {
2039 tss_seg.prev_task_link = old_tss_sel;
2040
2041 ret = ops->write_std(new_tss_base,
2042 &tss_seg.prev_task_link,
2043 sizeof tss_seg.prev_task_link,
2044 ctxt->vcpu, &ctxt->exception);
2045 if (ret != X86EMUL_CONTINUE)
2046 /* FIXME: need to provide precise fault address */
2047 return ret;
2048 }
2049
2050 return load_state_from_tss16(ctxt, ops, &tss_seg);
2051 }
2052
2053 static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt,
2054 struct x86_emulate_ops *ops,
2055 struct tss_segment_32 *tss)
2056 {
2057 struct decode_cache *c = &ctxt->decode;
2058
2059 tss->cr3 = ops->get_cr(3, ctxt->vcpu);
2060 tss->eip = c->eip;
2061 tss->eflags = ctxt->eflags;
2062 tss->eax = c->regs[VCPU_REGS_RAX];
2063 tss->ecx = c->regs[VCPU_REGS_RCX];
2064 tss->edx = c->regs[VCPU_REGS_RDX];
2065 tss->ebx = c->regs[VCPU_REGS_RBX];
2066 tss->esp = c->regs[VCPU_REGS_RSP];
2067 tss->ebp = c->regs[VCPU_REGS_RBP];
2068 tss->esi = c->regs[VCPU_REGS_RSI];
2069 tss->edi = c->regs[VCPU_REGS_RDI];
2070
2071 tss->es = ops->get_segment_selector(VCPU_SREG_ES, ctxt->vcpu);
2072 tss->cs = ops->get_segment_selector(VCPU_SREG_CS, ctxt->vcpu);
2073 tss->ss = ops->get_segment_selector(VCPU_SREG_SS, ctxt->vcpu);
2074 tss->ds = ops->get_segment_selector(VCPU_SREG_DS, ctxt->vcpu);
2075 tss->fs = ops->get_segment_selector(VCPU_SREG_FS, ctxt->vcpu);
2076 tss->gs = ops->get_segment_selector(VCPU_SREG_GS, ctxt->vcpu);
2077 tss->ldt_selector = ops->get_segment_selector(VCPU_SREG_LDTR, ctxt->vcpu);
2078 }
2079
2080 static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
2081 struct x86_emulate_ops *ops,
2082 struct tss_segment_32 *tss)
2083 {
2084 struct decode_cache *c = &ctxt->decode;
2085 int ret;
2086
2087 if (ops->set_cr(3, tss->cr3, ctxt->vcpu))
2088 return emulate_gp(ctxt, 0);
2089 c->eip = tss->eip;
2090 ctxt->eflags = tss->eflags | 2;
2091 c->regs[VCPU_REGS_RAX] = tss->eax;
2092 c->regs[VCPU_REGS_RCX] = tss->ecx;
2093 c->regs[VCPU_REGS_RDX] = tss->edx;
2094 c->regs[VCPU_REGS_RBX] = tss->ebx;
2095 c->regs[VCPU_REGS_RSP] = tss->esp;
2096 c->regs[VCPU_REGS_RBP] = tss->ebp;
2097 c->regs[VCPU_REGS_RSI] = tss->esi;
2098 c->regs[VCPU_REGS_RDI] = tss->edi;
2099
2100 /*
2101 * SDM says that segment selectors are loaded before segment
2102 * descriptors
2103 */
2104 ops->set_segment_selector(tss->ldt_selector, VCPU_SREG_LDTR, ctxt->vcpu);
2105 ops->set_segment_selector(tss->es, VCPU_SREG_ES, ctxt->vcpu);
2106 ops->set_segment_selector(tss->cs, VCPU_SREG_CS, ctxt->vcpu);
2107 ops->set_segment_selector(tss->ss, VCPU_SREG_SS, ctxt->vcpu);
2108 ops->set_segment_selector(tss->ds, VCPU_SREG_DS, ctxt->vcpu);
2109 ops->set_segment_selector(tss->fs, VCPU_SREG_FS, ctxt->vcpu);
2110 ops->set_segment_selector(tss->gs, VCPU_SREG_GS, ctxt->vcpu);
2111
2112 /*
2113 * Now load segment descriptors. If fault happenes at this stage
2114 * it is handled in a context of new task
2115 */
2116 ret = load_segment_descriptor(ctxt, ops, tss->ldt_selector, VCPU_SREG_LDTR);
2117 if (ret != X86EMUL_CONTINUE)
2118 return ret;
2119 ret = load_segment_descriptor(ctxt, ops, tss->es, VCPU_SREG_ES);
2120 if (ret != X86EMUL_CONTINUE)
2121 return ret;
2122 ret = load_segment_descriptor(ctxt, ops, tss->cs, VCPU_SREG_CS);
2123 if (ret != X86EMUL_CONTINUE)
2124 return ret;
2125 ret = load_segment_descriptor(ctxt, ops, tss->ss, VCPU_SREG_SS);
2126 if (ret != X86EMUL_CONTINUE)
2127 return ret;
2128 ret = load_segment_descriptor(ctxt, ops, tss->ds, VCPU_SREG_DS);
2129 if (ret != X86EMUL_CONTINUE)
2130 return ret;
2131 ret = load_segment_descriptor(ctxt, ops, tss->fs, VCPU_SREG_FS);
2132 if (ret != X86EMUL_CONTINUE)
2133 return ret;
2134 ret = load_segment_descriptor(ctxt, ops, tss->gs, VCPU_SREG_GS);
2135 if (ret != X86EMUL_CONTINUE)
2136 return ret;
2137
2138 return X86EMUL_CONTINUE;
2139 }
2140
2141 static int task_switch_32(struct x86_emulate_ctxt *ctxt,
2142 struct x86_emulate_ops *ops,
2143 u16 tss_selector, u16 old_tss_sel,
2144 ulong old_tss_base, struct desc_struct *new_desc)
2145 {
2146 struct tss_segment_32 tss_seg;
2147 int ret;
2148 u32 new_tss_base = get_desc_base(new_desc);
2149
2150 ret = ops->read_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2151 &ctxt->exception);
2152 if (ret != X86EMUL_CONTINUE)
2153 /* FIXME: need to provide precise fault address */
2154 return ret;
2155
2156 save_state_to_tss32(ctxt, ops, &tss_seg);
2157
2158 ret = ops->write_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2159 &ctxt->exception);
2160 if (ret != X86EMUL_CONTINUE)
2161 /* FIXME: need to provide precise fault address */
2162 return ret;
2163
2164 ret = ops->read_std(new_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu,
2165 &ctxt->exception);
2166 if (ret != X86EMUL_CONTINUE)
2167 /* FIXME: need to provide precise fault address */
2168 return ret;
2169
2170 if (old_tss_sel != 0xffff) {
2171 tss_seg.prev_task_link = old_tss_sel;
2172
2173 ret = ops->write_std(new_tss_base,
2174 &tss_seg.prev_task_link,
2175 sizeof tss_seg.prev_task_link,
2176 ctxt->vcpu, &ctxt->exception);
2177 if (ret != X86EMUL_CONTINUE)
2178 /* FIXME: need to provide precise fault address */
2179 return ret;
2180 }
2181
2182 return load_state_from_tss32(ctxt, ops, &tss_seg);
2183 }
2184
2185 static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
2186 struct x86_emulate_ops *ops,
2187 u16 tss_selector, int reason,
2188 bool has_error_code, u32 error_code)
2189 {
2190 struct desc_struct curr_tss_desc, next_tss_desc;
2191 int ret;
2192 u16 old_tss_sel = ops->get_segment_selector(VCPU_SREG_TR, ctxt->vcpu);
2193 ulong old_tss_base =
2194 ops->get_cached_segment_base(VCPU_SREG_TR, ctxt->vcpu);
2195 u32 desc_limit;
2196
2197 /* FIXME: old_tss_base == ~0 ? */
2198
2199 ret = read_segment_descriptor(ctxt, ops, tss_selector, &next_tss_desc);
2200 if (ret != X86EMUL_CONTINUE)
2201 return ret;
2202 ret = read_segment_descriptor(ctxt, ops, old_tss_sel, &curr_tss_desc);
2203 if (ret != X86EMUL_CONTINUE)
2204 return ret;
2205
2206 /* FIXME: check that next_tss_desc is tss */
2207
2208 if (reason != TASK_SWITCH_IRET) {
2209 if ((tss_selector & 3) > next_tss_desc.dpl ||
2210 ops->cpl(ctxt->vcpu) > next_tss_desc.dpl)
2211 return emulate_gp(ctxt, 0);
2212 }
2213
2214 desc_limit = desc_limit_scaled(&next_tss_desc);
2215 if (!next_tss_desc.p ||
2216 ((desc_limit < 0x67 && (next_tss_desc.type & 8)) ||
2217 desc_limit < 0x2b)) {
2218 emulate_ts(ctxt, tss_selector & 0xfffc);
2219 return X86EMUL_PROPAGATE_FAULT;
2220 }
2221
2222 if (reason == TASK_SWITCH_IRET || reason == TASK_SWITCH_JMP) {
2223 curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */
2224 write_segment_descriptor(ctxt, ops, old_tss_sel,
2225 &curr_tss_desc);
2226 }
2227
2228 if (reason == TASK_SWITCH_IRET)
2229 ctxt->eflags = ctxt->eflags & ~X86_EFLAGS_NT;
2230
2231 /* set back link to prev task only if NT bit is set in eflags
2232 note that old_tss_sel is not used afetr this point */
2233 if (reason != TASK_SWITCH_CALL && reason != TASK_SWITCH_GATE)
2234 old_tss_sel = 0xffff;
2235
2236 if (next_tss_desc.type & 8)
2237 ret = task_switch_32(ctxt, ops, tss_selector, old_tss_sel,
2238 old_tss_base, &next_tss_desc);
2239 else
2240 ret = task_switch_16(ctxt, ops, tss_selector, old_tss_sel,
2241 old_tss_base, &next_tss_desc);
2242 if (ret != X86EMUL_CONTINUE)
2243 return ret;
2244
2245 if (reason == TASK_SWITCH_CALL || reason == TASK_SWITCH_GATE)
2246 ctxt->eflags = ctxt->eflags | X86_EFLAGS_NT;
2247
2248 if (reason != TASK_SWITCH_IRET) {
2249 next_tss_desc.type |= (1 << 1); /* set busy flag */
2250 write_segment_descriptor(ctxt, ops, tss_selector,
2251 &next_tss_desc);
2252 }
2253
2254 ops->set_cr(0, ops->get_cr(0, ctxt->vcpu) | X86_CR0_TS, ctxt->vcpu);
2255 ops->set_cached_descriptor(&next_tss_desc, 0, VCPU_SREG_TR, ctxt->vcpu);
2256 ops->set_segment_selector(tss_selector, VCPU_SREG_TR, ctxt->vcpu);
2257
2258 if (has_error_code) {
2259 struct decode_cache *c = &ctxt->decode;
2260
2261 c->op_bytes = c->ad_bytes = (next_tss_desc.type & 8) ? 4 : 2;
2262 c->lock_prefix = 0;
2263 c->src.val = (unsigned long) error_code;
2264 emulate_push(ctxt, ops);
2265 }
2266
2267 return ret;
2268 }
2269
2270 int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
2271 u16 tss_selector, int reason,
2272 bool has_error_code, u32 error_code)
2273 {
2274 struct x86_emulate_ops *ops = ctxt->ops;
2275 struct decode_cache *c = &ctxt->decode;
2276 int rc;
2277
2278 c->eip = ctxt->eip;
2279 c->dst.type = OP_NONE;
2280
2281 rc = emulator_do_task_switch(ctxt, ops, tss_selector, reason,
2282 has_error_code, error_code);
2283
2284 if (rc == X86EMUL_CONTINUE) {
2285 rc = writeback(ctxt, ops);
2286 if (rc == X86EMUL_CONTINUE)
2287 ctxt->eip = c->eip;
2288 }
2289
2290 return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0;
2291 }
2292
2293 static void string_addr_inc(struct x86_emulate_ctxt *ctxt, unsigned seg,
2294 int reg, struct operand *op)
2295 {
2296 struct decode_cache *c = &ctxt->decode;
2297 int df = (ctxt->eflags & EFLG_DF) ? -1 : 1;
2298
2299 register_address_increment(c, &c->regs[reg], df * op->bytes);
2300 op->addr.mem.ea = register_address(c, c->regs[reg]);
2301 op->addr.mem.seg = seg;
2302 }
2303
2304 static int em_push(struct x86_emulate_ctxt *ctxt)
2305 {
2306 emulate_push(ctxt, ctxt->ops);
2307 return X86EMUL_CONTINUE;
2308 }
2309
2310 static int em_das(struct x86_emulate_ctxt *ctxt)
2311 {
2312 struct decode_cache *c = &ctxt->decode;
2313 u8 al, old_al;
2314 bool af, cf, old_cf;
2315
2316 cf = ctxt->eflags & X86_EFLAGS_CF;
2317 al = c->dst.val;
2318
2319 old_al = al;
2320 old_cf = cf;
2321 cf = false;
2322 af = ctxt->eflags & X86_EFLAGS_AF;
2323 if ((al & 0x0f) > 9 || af) {
2324 al -= 6;
2325 cf = old_cf | (al >= 250);
2326 af = true;
2327 } else {
2328 af = false;
2329 }
2330 if (old_al > 0x99 || old_cf) {
2331 al -= 0x60;
2332 cf = true;
2333 }
2334
2335 c->dst.val = al;
2336 /* Set PF, ZF, SF */
2337 c->src.type = OP_IMM;
2338 c->src.val = 0;
2339 c->src.bytes = 1;
2340 emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);
2341 ctxt->eflags &= ~(X86_EFLAGS_AF | X86_EFLAGS_CF);
2342 if (cf)
2343 ctxt->eflags |= X86_EFLAGS_CF;
2344 if (af)
2345 ctxt->eflags |= X86_EFLAGS_AF;
2346 return X86EMUL_CONTINUE;
2347 }
2348
2349 static int em_call_far(struct x86_emulate_ctxt *ctxt)
2350 {
2351 struct decode_cache *c = &ctxt->decode;
2352 u16 sel, old_cs;
2353 ulong old_eip;
2354 int rc;
2355
2356 old_cs = ctxt->ops->get_segment_selector(VCPU_SREG_CS, ctxt->vcpu);
2357 old_eip = c->eip;
2358
2359 memcpy(&sel, c->src.valptr + c->op_bytes, 2);
2360 if (load_segment_descriptor(ctxt, ctxt->ops, sel, VCPU_SREG_CS))
2361 return X86EMUL_CONTINUE;
2362
2363 c->eip = 0;
2364 memcpy(&c->eip, c->src.valptr, c->op_bytes);
2365
2366 c->src.val = old_cs;
2367 emulate_push(ctxt, ctxt->ops);
2368 rc = writeback(ctxt, ctxt->ops);
2369 if (rc != X86EMUL_CONTINUE)
2370 return rc;
2371
2372 c->src.val = old_eip;
2373 emulate_push(ctxt, ctxt->ops);
2374 rc = writeback(ctxt, ctxt->ops);
2375 if (rc != X86EMUL_CONTINUE)
2376 return rc;
2377
2378 c->dst.type = OP_NONE;
2379
2380 return X86EMUL_CONTINUE;
2381 }
2382
2383 static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
2384 {
2385 struct decode_cache *c = &ctxt->decode;
2386 int rc;
2387
2388 c->dst.type = OP_REG;
2389 c->dst.addr.reg = &c->eip;
2390 c->dst.bytes = c->op_bytes;
2391 rc = emulate_pop(ctxt, ctxt->ops, &c->dst.val, c->op_bytes);
2392 if (rc != X86EMUL_CONTINUE)
2393 return rc;
2394 register_address_increment(c, &c->regs[VCPU_REGS_RSP], c->src.val);
2395 return X86EMUL_CONTINUE;
2396 }
2397
2398 static int em_imul(struct x86_emulate_ctxt *ctxt)
2399 {
2400 struct decode_cache *c = &ctxt->decode;
2401
2402 emulate_2op_SrcV_nobyte("imul", c->src, c->dst, ctxt->eflags);
2403 return X86EMUL_CONTINUE;
2404 }
2405
2406 static int em_imul_3op(struct x86_emulate_ctxt *ctxt)
2407 {
2408 struct decode_cache *c = &ctxt->decode;
2409
2410 c->dst.val = c->src2.val;
2411 return em_imul(ctxt);
2412 }
2413
2414 static int em_cwd(struct x86_emulate_ctxt *ctxt)
2415 {
2416 struct decode_cache *c = &ctxt->decode;
2417
2418 c->dst.type = OP_REG;
2419 c->dst.bytes = c->src.bytes;
2420 c->dst.addr.reg = &c->regs[VCPU_REGS_RDX];
2421 c->dst.val = ~((c->src.val >> (c->src.bytes * 8 - 1)) - 1);
2422
2423 return X86EMUL_CONTINUE;
2424 }
2425
2426 static int em_rdtsc(struct x86_emulate_ctxt *ctxt)
2427 {
2428 struct decode_cache *c = &ctxt->decode;
2429 u64 tsc = 0;
2430
2431 ctxt->ops->get_msr(ctxt->vcpu, MSR_IA32_TSC, &tsc);
2432 c->regs[VCPU_REGS_RAX] = (u32)tsc;
2433 c->regs[VCPU_REGS_RDX] = tsc >> 32;
2434 return X86EMUL_CONTINUE;
2435 }
2436
2437 static int em_mov(struct x86_emulate_ctxt *ctxt)
2438 {
2439 struct decode_cache *c = &ctxt->decode;
2440 c->dst.val = c->src.val;
2441 return X86EMUL_CONTINUE;
2442 }
2443
2444 static int em_movdqu(struct x86_emulate_ctxt *ctxt)
2445 {
2446 struct decode_cache *c = &ctxt->decode;
2447 memcpy(&c->dst.vec_val, &c->src.vec_val, c->op_bytes);
2448 return X86EMUL_CONTINUE;
2449 }
2450
2451 static bool valid_cr(int nr)
2452 {
2453 switch (nr) {
2454 case 0:
2455 case 2 ... 4:
2456 case 8:
2457 return true;
2458 default:
2459 return false;
2460 }
2461 }
2462
2463 static int check_cr_read(struct x86_emulate_ctxt *ctxt)
2464 {
2465 struct decode_cache *c = &ctxt->decode;
2466
2467 if (!valid_cr(c->modrm_reg))
2468 return emulate_ud(ctxt);
2469
2470 return X86EMUL_CONTINUE;
2471 }
2472
2473 static int check_cr_write(struct x86_emulate_ctxt *ctxt)
2474 {
2475 struct decode_cache *c = &ctxt->decode;
2476 u64 new_val = c->src.val64;
2477 int cr = c->modrm_reg;
2478
2479 static u64 cr_reserved_bits[] = {
2480 0xffffffff00000000ULL,
2481 0, 0, 0, /* CR3 checked later */
2482 CR4_RESERVED_BITS,
2483 0, 0, 0,
2484 CR8_RESERVED_BITS,
2485 };
2486
2487 if (!valid_cr(cr))
2488 return emulate_ud(ctxt);
2489
2490 if (new_val & cr_reserved_bits[cr])
2491 return emulate_gp(ctxt, 0);
2492
2493 switch (cr) {
2494 case 0: {
2495 u64 cr4, efer;
2496 if (((new_val & X86_CR0_PG) && !(new_val & X86_CR0_PE)) ||
2497 ((new_val & X86_CR0_NW) && !(new_val & X86_CR0_CD)))
2498 return emulate_gp(ctxt, 0);
2499
2500 cr4 = ctxt->ops->get_cr(4, ctxt->vcpu);
2501 ctxt->ops->get_msr(ctxt->vcpu, MSR_EFER, &efer);
2502
2503 if ((new_val & X86_CR0_PG) && (efer & EFER_LME) &&
2504 !(cr4 & X86_CR4_PAE))
2505 return emulate_gp(ctxt, 0);
2506
2507 break;
2508 }
2509 case 3: {
2510 u64 rsvd = 0;
2511
2512 if (is_long_mode(ctxt->vcpu))
2513 rsvd = CR3_L_MODE_RESERVED_BITS;
2514 else if (is_pae(ctxt->vcpu))
2515 rsvd = CR3_PAE_RESERVED_BITS;
2516 else if (is_paging(ctxt->vcpu))
2517 rsvd = CR3_NONPAE_RESERVED_BITS;
2518
2519 if (new_val & rsvd)
2520 return emulate_gp(ctxt, 0);
2521
2522 break;
2523 }
2524 case 4: {
2525 u64 cr4, efer;
2526
2527 cr4 = ctxt->ops->get_cr(4, ctxt->vcpu);
2528 ctxt->ops->get_msr(ctxt->vcpu, MSR_EFER, &efer);
2529
2530 if ((efer & EFER_LMA) && !(new_val & X86_CR4_PAE))
2531 return emulate_gp(ctxt, 0);
2532
2533 break;
2534 }
2535 }
2536
2537 return X86EMUL_CONTINUE;
2538 }
2539
2540 static int check_dr7_gd(struct x86_emulate_ctxt *ctxt)
2541 {
2542 unsigned long dr7;
2543
2544 ctxt->ops->get_dr(7, &dr7, ctxt->vcpu);
2545
2546 /* Check if DR7.Global_Enable is set */
2547 return dr7 & (1 << 13);
2548 }
2549
2550 static int check_dr_read(struct x86_emulate_ctxt *ctxt)
2551 {
2552 struct decode_cache *c = &ctxt->decode;
2553 int dr = c->modrm_reg;
2554 u64 cr4;
2555
2556 if (dr > 7)
2557 return emulate_ud(ctxt);
2558
2559 cr4 = ctxt->ops->get_cr(4, ctxt->vcpu);
2560 if ((cr4 & X86_CR4_DE) && (dr == 4 || dr == 5))
2561 return emulate_ud(ctxt);
2562
2563 if (check_dr7_gd(ctxt))
2564 return emulate_db(ctxt);
2565
2566 return X86EMUL_CONTINUE;
2567 }
2568
2569 static int check_dr_write(struct x86_emulate_ctxt *ctxt)
2570 {
2571 struct decode_cache *c = &ctxt->decode;
2572 u64 new_val = c->src.val64;
2573 int dr = c->modrm_reg;
2574
2575 if ((dr == 6 || dr == 7) && (new_val & 0xffffffff00000000ULL))
2576 return emulate_gp(ctxt, 0);
2577
2578 return check_dr_read(ctxt);
2579 }
2580
2581 static int check_svme(struct x86_emulate_ctxt *ctxt)
2582 {
2583 u64 efer;
2584
2585 ctxt->ops->get_msr(ctxt->vcpu, MSR_EFER, &efer);
2586
2587 if (!(efer & EFER_SVME))
2588 return emulate_ud(ctxt);
2589
2590 return X86EMUL_CONTINUE;
2591 }
2592
2593 static int check_svme_pa(struct x86_emulate_ctxt *ctxt)
2594 {
2595 u64 rax = kvm_register_read(ctxt->vcpu, VCPU_REGS_RAX);
2596
2597 /* Valid physical address? */
2598 if (rax & 0xffff000000000000)
2599 return emulate_gp(ctxt, 0);
2600
2601 return check_svme(ctxt);
2602 }
2603
2604 static int check_rdtsc(struct x86_emulate_ctxt *ctxt)
2605 {
2606 u64 cr4 = ctxt->ops->get_cr(4, ctxt->vcpu);
2607
2608 if (cr4 & X86_CR4_TSD && ctxt->ops->cpl(ctxt->vcpu))
2609 return emulate_ud(ctxt);
2610
2611 return X86EMUL_CONTINUE;
2612 }
2613
2614 static int check_rdpmc(struct x86_emulate_ctxt *ctxt)
2615 {
2616 u64 cr4 = ctxt->ops->get_cr(4, ctxt->vcpu);
2617 u64 rcx = kvm_register_read(ctxt->vcpu, VCPU_REGS_RCX);
2618
2619 if ((!(cr4 & X86_CR4_PCE) && ctxt->ops->cpl(ctxt->vcpu)) ||
2620 (rcx > 3))
2621 return emulate_gp(ctxt, 0);
2622
2623 return X86EMUL_CONTINUE;
2624 }
2625
2626 #define D(_y) { .flags = (_y) }
2627 #define DI(_y, _i) { .flags = (_y), .intercept = x86_intercept_##_i }
2628 #define DIP(_y, _i, _p) { .flags = (_y), .intercept = x86_intercept_##_i, \
2629 .check_perm = (_p) }
2630 #define N D(0)
2631 #define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) }
2632 #define G(_f, _g) { .flags = ((_f) | Group), .u.group = (_g) }
2633 #define GD(_f, _g) { .flags = ((_f) | Group | GroupDual), .u.gdual = (_g) }
2634 #define I(_f, _e) { .flags = (_f), .u.execute = (_e) }
2635 #define II(_f, _e, _i) \
2636 { .flags = (_f), .u.execute = (_e), .intercept = x86_intercept_##_i }
2637 #define IIP(_f, _e, _i, _p) \
2638 { .flags = (_f), .u.execute = (_e), .intercept = x86_intercept_##_i, \
2639 .check_perm = (_p) }
2640 #define GP(_f, _g) { .flags = ((_f) | Prefix), .u.gprefix = (_g) }
2641
2642 #define D2bv(_f) D((_f) | ByteOp), D(_f)
2643 #define I2bv(_f, _e) I((_f) | ByteOp, _e), I(_f, _e)
2644
2645 #define D6ALU(_f) D2bv((_f) | DstMem | SrcReg | ModRM), \
2646 D2bv(((_f) | DstReg | SrcMem | ModRM) & ~Lock), \
2647 D2bv(((_f) & ~Lock) | DstAcc | SrcImm)
2648
2649 static struct opcode group7_rm1[] = {
2650 DI(SrcNone | ModRM | Priv, monitor),
2651 DI(SrcNone | ModRM | Priv, mwait),
2652 N, N, N, N, N, N,
2653 };
2654
2655 static struct opcode group7_rm3[] = {
2656 DIP(SrcNone | ModRM | Prot | Priv, vmrun, check_svme_pa),
2657 DIP(SrcNone | ModRM | Prot , vmmcall, check_svme),
2658 DIP(SrcNone | ModRM | Prot | Priv, vmload, check_svme_pa),
2659 DIP(SrcNone | ModRM | Prot | Priv, vmsave, check_svme_pa),
2660 DIP(SrcNone | ModRM | Prot | Priv, stgi, check_svme),
2661 DIP(SrcNone | ModRM | Prot | Priv, clgi, check_svme),
2662 DIP(SrcNone | ModRM | Prot | Priv, skinit, check_svme),
2663 DIP(SrcNone | ModRM | Prot | Priv, invlpga, check_svme),
2664 };
2665
2666 static struct opcode group7_rm7[] = {
2667 N,
2668 DIP(SrcNone | ModRM, rdtscp, check_rdtsc),
2669 N, N, N, N, N, N,
2670 };
2671 static struct opcode group1[] = {
2672 X7(D(Lock)), N
2673 };
2674
2675 static struct opcode group1A[] = {
2676 D(DstMem | SrcNone | ModRM | Mov | Stack), N, N, N, N, N, N, N,
2677 };
2678
2679 static struct opcode group3[] = {
2680 D(DstMem | SrcImm | ModRM), D(DstMem | SrcImm | ModRM),
2681 D(DstMem | SrcNone | ModRM | Lock), D(DstMem | SrcNone | ModRM | Lock),
2682 X4(D(SrcMem | ModRM)),
2683 };
2684
2685 static struct opcode group4[] = {
2686 D(ByteOp | DstMem | SrcNone | ModRM | Lock), D(ByteOp | DstMem | SrcNone | ModRM | Lock),
2687 N, N, N, N, N, N,
2688 };
2689
2690 static struct opcode group5[] = {
2691 D(DstMem | SrcNone | ModRM | Lock), D(DstMem | SrcNone | ModRM | Lock),
2692 D(SrcMem | ModRM | Stack),
2693 I(SrcMemFAddr | ModRM | ImplicitOps | Stack, em_call_far),
2694 D(SrcMem | ModRM | Stack), D(SrcMemFAddr | ModRM | ImplicitOps),
2695 D(SrcMem | ModRM | Stack), N,
2696 };
2697
2698 static struct opcode group6[] = {
2699 DI(ModRM | Prot, sldt),
2700 DI(ModRM | Prot, str),
2701 DI(ModRM | Prot | Priv, lldt),
2702 DI(ModRM | Prot | Priv, ltr),
2703 N, N, N, N,
2704 };
2705
2706 static struct group_dual group7 = { {
2707 DI(ModRM | Mov | DstMem | Priv, sgdt),
2708 DI(ModRM | Mov | DstMem | Priv, sidt),
2709 DI(ModRM | SrcMem | Priv, lgdt), DI(ModRM | SrcMem | Priv, lidt),
2710 DI(SrcNone | ModRM | DstMem | Mov, smsw), N,
2711 DI(SrcMem16 | ModRM | Mov | Priv, lmsw),
2712 DI(SrcMem | ModRM | ByteOp | Priv | NoAccess, invlpg),
2713 }, {
2714 D(SrcNone | ModRM | Priv | VendorSpecific), EXT(0, group7_rm1),
2715 N, EXT(0, group7_rm3),
2716 DI(SrcNone | ModRM | DstMem | Mov, smsw), N,
2717 DI(SrcMem16 | ModRM | Mov | Priv, lmsw), EXT(0, group7_rm7),
2718 } };
2719
2720 static struct opcode group8[] = {
2721 N, N, N, N,
2722 D(DstMem | SrcImmByte | ModRM), D(DstMem | SrcImmByte | ModRM | Lock),
2723 D(DstMem | SrcImmByte | ModRM | Lock), D(DstMem | SrcImmByte | ModRM | Lock),
2724 };
2725
2726 static struct group_dual group9 = { {
2727 N, D(DstMem64 | ModRM | Lock), N, N, N, N, N, N,
2728 }, {
2729 N, N, N, N, N, N, N, N,
2730 } };
2731
2732 static struct opcode group11[] = {
2733 I(DstMem | SrcImm | ModRM | Mov, em_mov), X7(D(Undefined)),
2734 };
2735
2736 static struct gprefix pfx_0f_6f_0f_7f = {
2737 N, N, N, I(Sse, em_movdqu),
2738 };
2739
2740 static struct opcode opcode_table[256] = {
2741 /* 0x00 - 0x07 */
2742 D6ALU(Lock),
2743 D(ImplicitOps | Stack | No64), D(ImplicitOps | Stack | No64),
2744 /* 0x08 - 0x0F */
2745 D6ALU(Lock),
2746 D(ImplicitOps | Stack | No64), N,
2747 /* 0x10 - 0x17 */
2748 D6ALU(Lock),
2749 D(ImplicitOps | Stack | No64), D(ImplicitOps | Stack | No64),
2750 /* 0x18 - 0x1F */
2751 D6ALU(Lock),
2752 D(ImplicitOps | Stack | No64), D(ImplicitOps | Stack | No64),
2753 /* 0x20 - 0x27 */
2754 D6ALU(Lock), N, N,
2755 /* 0x28 - 0x2F */
2756 D6ALU(Lock), N, I(ByteOp | DstAcc | No64, em_das),
2757 /* 0x30 - 0x37 */
2758 D6ALU(Lock), N, N,
2759 /* 0x38 - 0x3F */
2760 D6ALU(0), N, N,
2761 /* 0x40 - 0x4F */
2762 X16(D(DstReg)),
2763 /* 0x50 - 0x57 */
2764 X8(I(SrcReg | Stack, em_push)),
2765 /* 0x58 - 0x5F */
2766 X8(D(DstReg | Stack)),
2767 /* 0x60 - 0x67 */
2768 D(ImplicitOps | Stack | No64), D(ImplicitOps | Stack | No64),
2769 N, D(DstReg | SrcMem32 | ModRM | Mov) /* movsxd (x86/64) */ ,
2770 N, N, N, N,
2771 /* 0x68 - 0x6F */
2772 I(SrcImm | Mov | Stack, em_push),
2773 I(DstReg | SrcMem | ModRM | Src2Imm, em_imul_3op),
2774 I(SrcImmByte | Mov | Stack, em_push),
2775 I(DstReg | SrcMem | ModRM | Src2ImmByte, em_imul_3op),
2776 D2bv(DstDI | Mov | String), /* insb, insw/insd */
2777 D2bv(SrcSI | ImplicitOps | String), /* outsb, outsw/outsd */
2778 /* 0x70 - 0x7F */
2779 X16(D(SrcImmByte)),
2780 /* 0x80 - 0x87 */
2781 G(ByteOp | DstMem | SrcImm | ModRM | Group, group1),
2782 G(DstMem | SrcImm | ModRM | Group, group1),
2783 G(ByteOp | DstMem | SrcImm | ModRM | No64 | Group, group1),
2784 G(DstMem | SrcImmByte | ModRM | Group, group1),
2785 D2bv(DstMem | SrcReg | ModRM), D2bv(DstMem | SrcReg | ModRM | Lock),
2786 /* 0x88 - 0x8F */
2787 I2bv(DstMem | SrcReg | ModRM | Mov, em_mov),
2788 I2bv(DstReg | SrcMem | ModRM | Mov, em_mov),
2789 D(DstMem | SrcNone | ModRM | Mov), D(ModRM | SrcMem | NoAccess | DstReg),
2790 D(ImplicitOps | SrcMem16 | ModRM), G(0, group1A),
2791 /* 0x90 - 0x97 */
2792 X8(D(SrcAcc | DstReg)),
2793 /* 0x98 - 0x9F */
2794 D(DstAcc | SrcNone), I(ImplicitOps | SrcAcc, em_cwd),
2795 I(SrcImmFAddr | No64, em_call_far), N,
2796 DI(ImplicitOps | Stack, pushf), DI(ImplicitOps | Stack, popf), N, N,
2797 /* 0xA0 - 0xA7 */
2798 I2bv(DstAcc | SrcMem | Mov | MemAbs, em_mov),
2799 I2bv(DstMem | SrcAcc | Mov | MemAbs, em_mov),
2800 I2bv(SrcSI | DstDI | Mov | String, em_mov),
2801 D2bv(SrcSI | DstDI | String),
2802 /* 0xA8 - 0xAF */
2803 D2bv(DstAcc | SrcImm),
2804 I2bv(SrcAcc | DstDI | Mov | String, em_mov),
2805 I2bv(SrcSI | DstAcc | Mov | String, em_mov),
2806 D2bv(SrcAcc | DstDI | String),
2807 /* 0xB0 - 0xB7 */
2808 X8(I(ByteOp | DstReg | SrcImm | Mov, em_mov)),
2809 /* 0xB8 - 0xBF */
2810 X8(I(DstReg | SrcImm | Mov, em_mov)),
2811 /* 0xC0 - 0xC7 */
2812 D2bv(DstMem | SrcImmByte | ModRM),
2813 I(ImplicitOps | Stack | SrcImmU16, em_ret_near_imm),
2814 D(ImplicitOps | Stack),
2815 D(DstReg | SrcMemFAddr | ModRM | No64), D(DstReg | SrcMemFAddr | ModRM | No64),
2816 G(ByteOp, group11), G(0, group11),
2817 /* 0xC8 - 0xCF */
2818 N, N, N, D(ImplicitOps | Stack),
2819 D(ImplicitOps), DI(SrcImmByte, intn),
2820 D(ImplicitOps | No64), DI(ImplicitOps, iret),
2821 /* 0xD0 - 0xD7 */
2822 D2bv(DstMem | SrcOne | ModRM), D2bv(DstMem | ModRM),
2823 N, N, N, N,
2824 /* 0xD8 - 0xDF */
2825 N, N, N, N, N, N, N, N,
2826 /* 0xE0 - 0xE7 */
2827 X4(D(SrcImmByte)),
2828 D2bv(SrcImmUByte | DstAcc), D2bv(SrcAcc | DstImmUByte),
2829 /* 0xE8 - 0xEF */
2830 D(SrcImm | Stack), D(SrcImm | ImplicitOps),
2831 D(SrcImmFAddr | No64), D(SrcImmByte | ImplicitOps),
2832 D2bv(SrcNone | DstAcc), D2bv(SrcAcc | ImplicitOps),
2833 /* 0xF0 - 0xF7 */
2834 N, N, N, N,
2835 DI(ImplicitOps | Priv, hlt), D(ImplicitOps),
2836 G(ByteOp, group3), G(0, group3),
2837 /* 0xF8 - 0xFF */
2838 D(ImplicitOps), D(ImplicitOps), D(ImplicitOps), D(ImplicitOps),
2839 D(ImplicitOps), D(ImplicitOps), G(0, group4), G(0, group5),
2840 };
2841
2842 static struct opcode twobyte_table[256] = {
2843 /* 0x00 - 0x0F */
2844 G(0, group6), GD(0, &group7), N, N,
2845 N, D(ImplicitOps | VendorSpecific), DI(ImplicitOps | Priv, clts), N,
2846 DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
2847 N, D(ImplicitOps | ModRM), N, N,
2848 /* 0x10 - 0x1F */
2849 N, N, N, N, N, N, N, N, D(ImplicitOps | ModRM), N, N, N, N, N, N, N,
2850 /* 0x20 - 0x2F */
2851 DIP(ModRM | DstMem | Priv | Op3264, cr_read, check_cr_read),
2852 DIP(ModRM | DstMem | Priv | Op3264, dr_read, check_dr_read),
2853 DIP(ModRM | SrcMem | Priv | Op3264, cr_write, check_cr_write),
2854 DIP(ModRM | SrcMem | Priv | Op3264, dr_write, check_dr_write),
2855 N, N, N, N,
2856 N, N, N, N, N, N, N, N,
2857 /* 0x30 - 0x3F */
2858 DI(ImplicitOps | Priv, wrmsr),
2859 IIP(ImplicitOps, em_rdtsc, rdtsc, check_rdtsc),
2860 DI(ImplicitOps | Priv, rdmsr),
2861 DIP(ImplicitOps | Priv, rdpmc, check_rdpmc),
2862 D(ImplicitOps | VendorSpecific), D(ImplicitOps | Priv | VendorSpecific),
2863 N, N,
2864 N, N, N, N, N, N, N, N,
2865 /* 0x40 - 0x4F */
2866 X16(D(DstReg | SrcMem | ModRM | Mov)),
2867 /* 0x50 - 0x5F */
2868 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N,
2869 /* 0x60 - 0x6F */
2870 N, N, N, N,
2871 N, N, N, N,
2872 N, N, N, N,
2873 N, N, N, GP(SrcMem | DstReg | ModRM | Mov, &pfx_0f_6f_0f_7f),
2874 /* 0x70 - 0x7F */
2875 N, N, N, N,
2876 N, N, N, N,
2877 N, N, N, N,
2878 N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_6f_0f_7f),
2879 /* 0x80 - 0x8F */
2880 X16(D(SrcImm)),
2881 /* 0x90 - 0x9F */
2882 X16(D(ByteOp | DstMem | SrcNone | ModRM| Mov)),
2883 /* 0xA0 - 0xA7 */
2884 D(ImplicitOps | Stack), D(ImplicitOps | Stack),
2885 DI(ImplicitOps, cpuid), D(DstMem | SrcReg | ModRM | BitOp),
2886 D(DstMem | SrcReg | Src2ImmByte | ModRM),
2887 D(DstMem | SrcReg | Src2CL | ModRM), N, N,
2888 /* 0xA8 - 0xAF */
2889 D(ImplicitOps | Stack), D(ImplicitOps | Stack),
2890 DI(ImplicitOps, rsm), D(DstMem | SrcReg | ModRM | BitOp | Lock),
2891 D(DstMem | SrcReg | Src2ImmByte | ModRM),
2892 D(DstMem | SrcReg | Src2CL | ModRM),
2893 D(ModRM), I(DstReg | SrcMem | ModRM, em_imul),
2894 /* 0xB0 - 0xB7 */
2895 D2bv(DstMem | SrcReg | ModRM | Lock),
2896 D(DstReg | SrcMemFAddr | ModRM), D(DstMem | SrcReg | ModRM | BitOp | Lock),
2897 D(DstReg | SrcMemFAddr | ModRM), D(DstReg | SrcMemFAddr | ModRM),
2898 D(ByteOp | DstReg | SrcMem | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
2899 /* 0xB8 - 0xBF */
2900 N, N,
2901 G(BitOp, group8), D(DstMem | SrcReg | ModRM | BitOp | Lock),
2902 D(DstReg | SrcMem | ModRM), D(DstReg | SrcMem | ModRM),
2903 D(ByteOp | DstReg | SrcMem | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
2904 /* 0xC0 - 0xCF */
2905 D2bv(DstMem | SrcReg | ModRM | Lock),
2906 N, D(DstMem | SrcReg | ModRM | Mov),
2907 N, N, N, GD(0, &group9),
2908 N, N, N, N, N, N, N, N,
2909 /* 0xD0 - 0xDF */
2910 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N,
2911 /* 0xE0 - 0xEF */
2912 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N,
2913 /* 0xF0 - 0xFF */
2914 N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N
2915 };
2916
2917 #undef D
2918 #undef N
2919 #undef G
2920 #undef GD
2921 #undef I
2922 #undef GP
2923 #undef EXT
2924
2925 #undef D2bv
2926 #undef I2bv
2927 #undef D6ALU
2928
2929 static unsigned imm_size(struct decode_cache *c)
2930 {
2931 unsigned size;
2932
2933 size = (c->d & ByteOp) ? 1 : c->op_bytes;
2934 if (size == 8)
2935 size = 4;
2936 return size;
2937 }
2938
2939 static int decode_imm(struct x86_emulate_ctxt *ctxt, struct operand *op,
2940 unsigned size, bool sign_extension)
2941 {
2942 struct decode_cache *c = &ctxt->decode;
2943 struct x86_emulate_ops *ops = ctxt->ops;
2944 int rc = X86EMUL_CONTINUE;
2945
2946 op->type = OP_IMM;
2947 op->bytes = size;
2948 op->addr.mem.ea = c->eip;
2949 /* NB. Immediates are sign-extended as necessary. */
2950 switch (op->bytes) {
2951 case 1:
2952 op->val = insn_fetch(s8, 1, c->eip);
2953 break;
2954 case 2:
2955 op->val = insn_fetch(s16, 2, c->eip);
2956 break;
2957 case 4:
2958 op->val = insn_fetch(s32, 4, c->eip);
2959 break;
2960 }
2961 if (!sign_extension) {
2962 switch (op->bytes) {
2963 case 1:
2964 op->val &= 0xff;
2965 break;
2966 case 2:
2967 op->val &= 0xffff;
2968 break;
2969 case 4:
2970 op->val &= 0xffffffff;
2971 break;
2972 }
2973 }
2974 done:
2975 return rc;
2976 }
2977
2978 int
2979 x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
2980 {
2981 struct x86_emulate_ops *ops = ctxt->ops;
2982 struct decode_cache *c = &ctxt->decode;
2983 int rc = X86EMUL_CONTINUE;
2984 int mode = ctxt->mode;
2985 int def_op_bytes, def_ad_bytes, dual, goffset, simd_prefix;
2986 bool op_prefix = false;
2987 struct opcode opcode, *g_mod012, *g_mod3;
2988 struct operand memop = { .type = OP_NONE };
2989
2990 c->eip = ctxt->eip;
2991 c->fetch.start = c->eip;
2992 c->fetch.end = c->fetch.start + insn_len;
2993 if (insn_len > 0)
2994 memcpy(c->fetch.data, insn, insn_len);
2995 ctxt->cs_base = seg_base(ctxt, ops, VCPU_SREG_CS);
2996
2997 switch (mode) {
2998 case X86EMUL_MODE_REAL:
2999 case X86EMUL_MODE_VM86:
3000 case X86EMUL_MODE_PROT16:
3001 def_op_bytes = def_ad_bytes = 2;
3002 break;
3003 case X86EMUL_MODE_PROT32:
3004 def_op_bytes = def_ad_bytes = 4;
3005 break;
3006 #ifdef CONFIG_X86_64
3007 case X86EMUL_MODE_PROT64:
3008 def_op_bytes = 4;
3009 def_ad_bytes = 8;
3010 break;
3011 #endif
3012 default:
3013 return -1;
3014 }
3015
3016 c->op_bytes = def_op_bytes;
3017 c->ad_bytes = def_ad_bytes;
3018
3019 /* Legacy prefixes. */
3020 for (;;) {
3021 switch (c->b = insn_fetch(u8, 1, c->eip)) {
3022 case 0x66: /* operand-size override */
3023 op_prefix = true;
3024 /* switch between 2/4 bytes */
3025 c->op_bytes = def_op_bytes ^ 6;
3026 break;
3027 case 0x67: /* address-size override */
3028 if (mode == X86EMUL_MODE_PROT64)
3029 /* switch between 4/8 bytes */
3030 c->ad_bytes = def_ad_bytes ^ 12;
3031 else
3032 /* switch between 2/4 bytes */
3033 c->ad_bytes = def_ad_bytes ^ 6;
3034 break;
3035 case 0x26: /* ES override */
3036 case 0x2e: /* CS override */
3037 case 0x36: /* SS override */
3038 case 0x3e: /* DS override */
3039 set_seg_override(c, (c->b >> 3) & 3);
3040 break;
3041 case 0x64: /* FS override */
3042 case 0x65: /* GS override */
3043 set_seg_override(c, c->b & 7);
3044 break;
3045 case 0x40 ... 0x4f: /* REX */
3046 if (mode != X86EMUL_MODE_PROT64)
3047 goto done_prefixes;
3048 c->rex_prefix = c->b;
3049 continue;
3050 case 0xf0: /* LOCK */
3051 c->lock_prefix = 1;
3052 break;
3053 case 0xf2: /* REPNE/REPNZ */
3054 case 0xf3: /* REP/REPE/REPZ */
3055 c->rep_prefix = c->b;
3056 break;
3057 default:
3058 goto done_prefixes;
3059 }
3060
3061 /* Any legacy prefix after a REX prefix nullifies its effect. */
3062
3063 c->rex_prefix = 0;
3064 }
3065
3066 done_prefixes:
3067
3068 /* REX prefix. */
3069 if (c->rex_prefix & 8)
3070 c->op_bytes = 8; /* REX.W */
3071
3072 /* Opcode byte(s). */
3073 opcode = opcode_table[c->b];
3074 /* Two-byte opcode? */
3075 if (c->b == 0x0f) {
3076 c->twobyte = 1;
3077 c->b = insn_fetch(u8, 1, c->eip);
3078 opcode = twobyte_table[c->b];
3079 }
3080 c->d = opcode.flags;
3081
3082 if (c->d & Group) {
3083 dual = c->d & GroupDual;
3084 c->modrm = insn_fetch(u8, 1, c->eip);
3085 --c->eip;
3086
3087 if (c->d & GroupDual) {
3088 g_mod012 = opcode.u.gdual->mod012;
3089 g_mod3 = opcode.u.gdual->mod3;
3090 } else
3091 g_mod012 = g_mod3 = opcode.u.group;
3092
3093 c->d &= ~(Group | GroupDual);
3094
3095 goffset = (c->modrm >> 3) & 7;
3096
3097 if ((c->modrm >> 6) == 3)
3098 opcode = g_mod3[goffset];
3099 else
3100 opcode = g_mod012[goffset];
3101
3102 if (opcode.flags & RMExt) {
3103 goffset = c->modrm & 7;
3104 opcode = opcode.u.group[goffset];
3105 }
3106
3107 c->d |= opcode.flags;
3108 }
3109
3110 if (c->d & Prefix) {
3111 if (c->rep_prefix && op_prefix)
3112 return X86EMUL_UNHANDLEABLE;
3113 simd_prefix = op_prefix ? 0x66 : c->rep_prefix;
3114 switch (simd_prefix) {
3115 case 0x00: opcode = opcode.u.gprefix->pfx_no; break;
3116 case 0x66: opcode = opcode.u.gprefix->pfx_66; break;
3117 case 0xf2: opcode = opcode.u.gprefix->pfx_f2; break;
3118 case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break;
3119 }
3120 c->d |= opcode.flags;
3121 }
3122
3123 c->execute = opcode.u.execute;
3124 c->check_perm = opcode.check_perm;
3125 c->intercept = opcode.intercept;
3126
3127 /* Unrecognised? */
3128 if (c->d == 0 || (c->d & Undefined))
3129 return -1;
3130
3131 if (!(c->d & VendorSpecific) && ctxt->only_vendor_specific_insn)
3132 return -1;
3133
3134 if (mode == X86EMUL_MODE_PROT64 && (c->d & Stack))
3135 c->op_bytes = 8;
3136
3137 if (c->d & Op3264) {
3138 if (mode == X86EMUL_MODE_PROT64)
3139 c->op_bytes = 8;
3140 else
3141 c->op_bytes = 4;
3142 }
3143
3144 if (c->d & Sse)
3145 c->op_bytes = 16;
3146
3147 /* ModRM and SIB bytes. */
3148 if (c->d & ModRM) {
3149 rc = decode_modrm(ctxt, ops, &memop);
3150 if (!c->has_seg_override)
3151 set_seg_override(c, c->modrm_seg);
3152 } else if (c->d & MemAbs)
3153 rc = decode_abs(ctxt, ops, &memop);
3154 if (rc != X86EMUL_CONTINUE)
3155 goto done;
3156
3157 if (!c->has_seg_override)
3158 set_seg_override(c, VCPU_SREG_DS);
3159
3160 memop.addr.mem.seg = seg_override(ctxt, ops, c);
3161
3162 if (memop.type == OP_MEM && c->ad_bytes != 8)
3163 memop.addr.mem.ea = (u32)memop.addr.mem.ea;
3164
3165 if (memop.type == OP_MEM && c->rip_relative)
3166 memop.addr.mem.ea += c->eip;
3167
3168 /*
3169 * Decode and fetch the source operand: register, memory
3170 * or immediate.
3171 */
3172 switch (c->d & SrcMask) {
3173 case SrcNone:
3174 break;
3175 case SrcReg:
3176 decode_register_operand(ctxt, &c->src, c, 0);
3177 break;
3178 case SrcMem16:
3179 memop.bytes = 2;
3180 goto srcmem_common;
3181 case SrcMem32:
3182 memop.bytes = 4;
3183 goto srcmem_common;
3184 case SrcMem:
3185 memop.bytes = (c->d & ByteOp) ? 1 :
3186 c->op_bytes;
3187 srcmem_common:
3188 c->src = memop;
3189 break;
3190 case SrcImmU16:
3191 rc = decode_imm(ctxt, &c->src, 2, false);
3192 break;
3193 case SrcImm:
3194 rc = decode_imm(ctxt, &c->src, imm_size(c), true);
3195 break;
3196 case SrcImmU:
3197 rc = decode_imm(ctxt, &c->src, imm_size(c), false);
3198 break;
3199 case SrcImmByte:
3200 rc = decode_imm(ctxt, &c->src, 1, true);
3201 break;
3202 case SrcImmUByte:
3203 rc = decode_imm(ctxt, &c->src, 1, false);
3204 break;
3205 case SrcAcc:
3206 c->src.type = OP_REG;
3207 c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
3208 c->src.addr.reg = &c->regs[VCPU_REGS_RAX];
3209 fetch_register_operand(&c->src);
3210 break;
3211 case SrcOne:
3212 c->src.bytes = 1;
3213 c->src.val = 1;
3214 break;
3215 case SrcSI:
3216 c->src.type = OP_MEM;
3217 c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
3218 c->src.addr.mem.ea =
3219 register_address(c, c->regs[VCPU_REGS_RSI]);
3220 c->src.addr.mem.seg = seg_override(ctxt, ops, c),
3221 c->src.val = 0;
3222 break;
3223 case SrcImmFAddr:
3224 c->src.type = OP_IMM;
3225 c->src.addr.mem.ea = c->eip;
3226 c->src.bytes = c->op_bytes + 2;
3227 insn_fetch_arr(c->src.valptr, c->src.bytes, c->eip);
3228 break;
3229 case SrcMemFAddr:
3230 memop.bytes = c->op_bytes + 2;
3231 goto srcmem_common;
3232 break;
3233 }
3234
3235 if (rc != X86EMUL_CONTINUE)
3236 goto done;
3237
3238 /*
3239 * Decode and fetch the second source operand: register, memory
3240 * or immediate.
3241 */
3242 switch (c->d & Src2Mask) {
3243 case Src2None:
3244 break;
3245 case Src2CL:
3246 c->src2.bytes = 1;
3247 c->src2.val = c->regs[VCPU_REGS_RCX] & 0x8;
3248 break;
3249 case Src2ImmByte:
3250 rc = decode_imm(ctxt, &c->src2, 1, true);
3251 break;
3252 case Src2One:
3253 c->src2.bytes = 1;
3254 c->src2.val = 1;
3255 break;
3256 case Src2Imm:
3257 rc = decode_imm(ctxt, &c->src2, imm_size(c), true);
3258 break;
3259 }
3260
3261 if (rc != X86EMUL_CONTINUE)
3262 goto done;
3263
3264 /* Decode and fetch the destination operand: register or memory. */
3265 switch (c->d & DstMask) {
3266 case DstReg:
3267 decode_register_operand(ctxt, &c->dst, c,
3268 c->twobyte && (c->b == 0xb6 || c->b == 0xb7));
3269 break;
3270 case DstImmUByte:
3271 c->dst.type = OP_IMM;
3272 c->dst.addr.mem.ea = c->eip;
3273 c->dst.bytes = 1;
3274 c->dst.val = insn_fetch(u8, 1, c->eip);
3275 break;
3276 case DstMem:
3277 case DstMem64:
3278 c->dst = memop;
3279 if ((c->d & DstMask) == DstMem64)
3280 c->dst.bytes = 8;
3281 else
3282 c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
3283 if (c->d & BitOp)
3284 fetch_bit_operand(c);
3285 c->dst.orig_val = c->dst.val;
3286 break;
3287 case DstAcc:
3288 c->dst.type = OP_REG;
3289 c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
3290 c->dst.addr.reg = &c->regs[VCPU_REGS_RAX];
3291 fetch_register_operand(&c->dst);
3292 c->dst.orig_val = c->dst.val;
3293 break;
3294 case DstDI:
3295 c->dst.type = OP_MEM;
3296 c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
3297 c->dst.addr.mem.ea =
3298 register_address(c, c->regs[VCPU_REGS_RDI]);
3299 c->dst.addr.mem.seg = VCPU_SREG_ES;
3300 c->dst.val = 0;
3301 break;
3302 case ImplicitOps:
3303 /* Special instructions do their own operand decoding. */
3304 default:
3305 c->dst.type = OP_NONE; /* Disable writeback. */
3306 return 0;
3307 }
3308
3309 done:
3310 return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0;
3311 }
3312
3313 static bool string_insn_completed(struct x86_emulate_ctxt *ctxt)
3314 {
3315 struct decode_cache *c = &ctxt->decode;
3316
3317 /* The second termination condition only applies for REPE
3318 * and REPNE. Test if the repeat string operation prefix is
3319 * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the
3320 * corresponding termination condition according to:
3321 * - if REPE/REPZ and ZF = 0 then done
3322 * - if REPNE/REPNZ and ZF = 1 then done
3323 */
3324 if (((c->b == 0xa6) || (c->b == 0xa7) ||
3325 (c->b == 0xae) || (c->b == 0xaf))
3326 && (((c->rep_prefix == REPE_PREFIX) &&
3327 ((ctxt->eflags & EFLG_ZF) == 0))
3328 || ((c->rep_prefix == REPNE_PREFIX) &&
3329 ((ctxt->eflags & EFLG_ZF) == EFLG_ZF))))
3330 return true;
3331
3332 return false;
3333 }
3334
3335 int
3336 x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
3337 {
3338 struct x86_emulate_ops *ops = ctxt->ops;
3339 u64 msr_data;
3340 struct decode_cache *c = &ctxt->decode;
3341 int rc = X86EMUL_CONTINUE;
3342 int saved_dst_type = c->dst.type;
3343 int irq; /* Used for int 3, int, and into */
3344
3345 ctxt->decode.mem_read.pos = 0;
3346
3347 if (ctxt->mode == X86EMUL_MODE_PROT64 && (c->d & No64)) {
3348 rc = emulate_ud(ctxt);
3349 goto done;
3350 }
3351
3352 /* LOCK prefix is allowed only with some instructions */
3353 if (c->lock_prefix && (!(c->d & Lock) || c->dst.type != OP_MEM)) {
3354 rc = emulate_ud(ctxt);
3355 goto done;
3356 }
3357
3358 if ((c->d & SrcMask) == SrcMemFAddr && c->src.type != OP_MEM) {
3359 rc = emulate_ud(ctxt);
3360 goto done;
3361 }
3362
3363 if ((c->d & Sse)
3364 && ((ops->get_cr(0, ctxt->vcpu) & X86_CR0_EM)
3365 || !(ops->get_cr(4, ctxt->vcpu) & X86_CR4_OSFXSR))) {
3366 rc = emulate_ud(ctxt);
3367 goto done;
3368 }
3369
3370 if ((c->d & Sse) && (ops->get_cr(0, ctxt->vcpu) & X86_CR0_TS)) {
3371 rc = emulate_nm(ctxt);
3372 goto done;
3373 }
3374
3375 if (unlikely(ctxt->guest_mode) && c->intercept) {
3376 rc = emulator_check_intercept(ctxt, c->intercept,
3377 X86_ICPT_PRE_EXCEPT);
3378 if (rc != X86EMUL_CONTINUE)
3379 goto done;
3380 }
3381
3382 /* Privileged instruction can be executed only in CPL=0 */
3383 if ((c->d & Priv) && ops->cpl(ctxt->vcpu)) {
3384 rc = emulate_gp(ctxt, 0);
3385 goto done;
3386 }
3387
3388 /* Instruction can only be executed in protected mode */
3389 if ((c->d & Prot) && !(ctxt->mode & X86EMUL_MODE_PROT)) {
3390 rc = emulate_ud(ctxt);
3391 goto done;
3392 }
3393
3394 /* Do instruction specific permission checks */
3395 if (c->check_perm) {
3396 rc = c->check_perm(ctxt);
3397 if (rc != X86EMUL_CONTINUE)
3398 goto done;
3399 }
3400
3401 if (unlikely(ctxt->guest_mode) && c->intercept) {
3402 rc = emulator_check_intercept(ctxt, c->intercept,
3403 X86_ICPT_POST_EXCEPT);
3404 if (rc != X86EMUL_CONTINUE)
3405 goto done;
3406 }
3407
3408 if (c->rep_prefix && (c->d & String)) {
3409 /* All REP prefixes have the same first termination condition */
3410 if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0) {
3411 ctxt->eip = c->eip;
3412 goto done;
3413 }
3414 }
3415
3416 if ((c->src.type == OP_MEM) && !(c->d & NoAccess)) {
3417 rc = read_emulated(ctxt, ops, linear(ctxt, c->src.addr.mem),
3418 c->src.valptr, c->src.bytes);
3419 if (rc != X86EMUL_CONTINUE)
3420 goto done;
3421 c->src.orig_val64 = c->src.val64;
3422 }
3423
3424 if (c->src2.type == OP_MEM) {
3425 rc = read_emulated(ctxt, ops, linear(ctxt, c->src2.addr.mem),
3426 &c->src2.val, c->src2.bytes);
3427 if (rc != X86EMUL_CONTINUE)
3428 goto done;
3429 }
3430
3431 if ((c->d & DstMask) == ImplicitOps)
3432 goto special_insn;
3433
3434
3435 if ((c->dst.type == OP_MEM) && !(c->d & Mov)) {
3436 /* optimisation - avoid slow emulated read if Mov */
3437 rc = read_emulated(ctxt, ops, linear(ctxt, c->dst.addr.mem),
3438 &c->dst.val, c->dst.bytes);
3439 if (rc != X86EMUL_CONTINUE)
3440 goto done;
3441 }
3442 c->dst.orig_val = c->dst.val;
3443
3444 special_insn:
3445
3446 if (unlikely(ctxt->guest_mode) && c->intercept) {
3447 rc = emulator_check_intercept(ctxt, c->intercept,
3448 X86_ICPT_POST_MEMACCESS);
3449 if (rc != X86EMUL_CONTINUE)
3450 goto done;
3451 }
3452
3453 if (c->execute) {
3454 rc = c->execute(ctxt);
3455 if (rc != X86EMUL_CONTINUE)
3456 goto done;
3457 goto writeback;
3458 }
3459
3460 if (c->twobyte)
3461 goto twobyte_insn;
3462
3463 switch (c->b) {
3464 case 0x00 ... 0x05:
3465 add: /* add */
3466 emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
3467 break;
3468 case 0x06: /* push es */
3469 emulate_push_sreg(ctxt, ops, VCPU_SREG_ES);
3470 break;
3471 case 0x07: /* pop es */
3472 rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES);
3473 break;
3474 case 0x08 ... 0x0d:
3475 or: /* or */
3476 emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);
3477 break;
3478 case 0x0e: /* push cs */
3479 emulate_push_sreg(ctxt, ops, VCPU_SREG_CS);
3480 break;
3481 case 0x10 ... 0x15:
3482 adc: /* adc */
3483 emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags);
3484 break;
3485 case 0x16: /* push ss */
3486 emulate_push_sreg(ctxt, ops, VCPU_SREG_SS);
3487 break;
3488 case 0x17: /* pop ss */
3489 rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS);
3490 break;
3491 case 0x18 ... 0x1d:
3492 sbb: /* sbb */
3493 emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags);
3494 break;
3495 case 0x1e: /* push ds */
3496 emulate_push_sreg(ctxt, ops, VCPU_SREG_DS);
3497 break;
3498 case 0x1f: /* pop ds */
3499 rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS);
3500 break;
3501 case 0x20 ... 0x25:
3502 and: /* and */
3503 emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags);
3504 break;
3505 case 0x28 ... 0x2d:
3506 sub: /* sub */
3507 emulate_2op_SrcV("sub", c->src, c->dst, ctxt->eflags);
3508 break;
3509 case 0x30 ... 0x35:
3510 xor: /* xor */
3511 emulate_2op_SrcV("xor", c->src, c->dst, ctxt->eflags);
3512 break;
3513 case 0x38 ... 0x3d:
3514 cmp: /* cmp */
3515 emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
3516 break;
3517 case 0x40 ... 0x47: /* inc r16/r32 */
3518 emulate_1op("inc", c->dst, ctxt->eflags);
3519 break;
3520 case 0x48 ... 0x4f: /* dec r16/r32 */
3521 emulate_1op("dec", c->dst, ctxt->eflags);
3522 break;
3523 case 0x58 ... 0x5f: /* pop reg */
3524 pop_instruction:
3525 rc = emulate_pop(ctxt, ops, &c->dst.val, c->op_bytes);
3526 break;
3527 case 0x60: /* pusha */
3528 rc = emulate_pusha(ctxt, ops);
3529 break;
3530 case 0x61: /* popa */
3531 rc = emulate_popa(ctxt, ops);
3532 break;
3533 case 0x63: /* movsxd */
3534 if (ctxt->mode != X86EMUL_MODE_PROT64)
3535 goto cannot_emulate;
3536 c->dst.val = (s32) c->src.val;
3537 break;
3538 case 0x6c: /* insb */
3539 case 0x6d: /* insw/insd */
3540 c->src.val = c->regs[VCPU_REGS_RDX];
3541 goto do_io_in;
3542 case 0x6e: /* outsb */
3543 case 0x6f: /* outsw/outsd */
3544 c->dst.val = c->regs[VCPU_REGS_RDX];
3545 goto do_io_out;
3546 break;
3547 case 0x70 ... 0x7f: /* jcc (short) */
3548 if (test_cc(c->b, ctxt->eflags))
3549 jmp_rel(c, c->src.val);
3550 break;
3551 case 0x80 ... 0x83: /* Grp1 */
3552 switch (c->modrm_reg) {
3553 case 0:
3554 goto add;
3555 case 1:
3556 goto or;
3557 case 2:
3558 goto adc;
3559 case 3:
3560 goto sbb;
3561 case 4:
3562 goto and;
3563 case 5:
3564 goto sub;
3565 case 6:
3566 goto xor;
3567 case 7:
3568 goto cmp;
3569 }
3570 break;
3571 case 0x84 ... 0x85:
3572 test:
3573 emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
3574 break;
3575 case 0x86 ... 0x87: /* xchg */
3576 xchg:
3577 /* Write back the register source. */
3578 c->src.val = c->dst.val;
3579 write_register_operand(&c->src);
3580 /*
3581 * Write back the memory destination with implicit LOCK
3582 * prefix.
3583 */
3584 c->dst.val = c->src.orig_val;
3585 c->lock_prefix = 1;
3586 break;
3587 case 0x8c: /* mov r/m, sreg */
3588 if (c->modrm_reg > VCPU_SREG_GS) {
3589 rc = emulate_ud(ctxt);
3590 goto done;
3591 }
3592 c->dst.val = ops->get_segment_selector(c->modrm_reg, ctxt->vcpu);
3593 break;
3594 case 0x8d: /* lea r16/r32, m */
3595 c->dst.val = c->src.addr.mem.ea;
3596 break;
3597 case 0x8e: { /* mov seg, r/m16 */
3598 uint16_t sel;
3599
3600 sel = c->src.val;
3601
3602 if (c->modrm_reg == VCPU_SREG_CS ||
3603 c->modrm_reg > VCPU_SREG_GS) {
3604 rc = emulate_ud(ctxt);
3605 goto done;
3606 }
3607
3608 if (c->modrm_reg == VCPU_SREG_SS)
3609 ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
3610
3611 rc = load_segment_descriptor(ctxt, ops, sel, c->modrm_reg);
3612
3613 c->dst.type = OP_NONE; /* Disable writeback. */
3614 break;
3615 }
3616 case 0x8f: /* pop (sole member of Grp1a) */
3617 rc = emulate_grp1a(ctxt, ops);
3618 break;
3619 case 0x90 ... 0x97: /* nop / xchg reg, rax */
3620 if (c->dst.addr.reg == &c->regs[VCPU_REGS_RAX])
3621 break;
3622 goto xchg;
3623 case 0x98: /* cbw/cwde/cdqe */
3624 switch (c->op_bytes) {
3625 case 2: c->dst.val = (s8)c->dst.val; break;
3626 case 4: c->dst.val = (s16)c->dst.val; break;
3627 case 8: c->dst.val = (s32)c->dst.val; break;
3628 }
3629 break;
3630 case 0x9c: /* pushf */
3631 c->src.val = (unsigned long) ctxt->eflags;
3632 emulate_push(ctxt, ops);
3633 break;
3634 case 0x9d: /* popf */
3635 c->dst.type = OP_REG;
3636 c->dst.addr.reg = &ctxt->eflags;
3637 c->dst.bytes = c->op_bytes;
3638 rc = emulate_popf(ctxt, ops, &c->dst.val, c->op_bytes);
3639 break;
3640 case 0xa6 ... 0xa7: /* cmps */
3641 c->dst.type = OP_NONE; /* Disable writeback. */
3642 goto cmp;
3643 case 0xa8 ... 0xa9: /* test ax, imm */
3644 goto test;
3645 case 0xae ... 0xaf: /* scas */
3646 goto cmp;
3647 case 0xc0 ... 0xc1:
3648 emulate_grp2(ctxt);
3649 break;
3650 case 0xc3: /* ret */
3651 c->dst.type = OP_REG;
3652 c->dst.addr.reg = &c->eip;
3653 c->dst.bytes = c->op_bytes;
3654 goto pop_instruction;
3655 case 0xc4: /* les */
3656 rc = emulate_load_segment(ctxt, ops, VCPU_SREG_ES);
3657 break;
3658 case 0xc5: /* lds */
3659 rc = emulate_load_segment(ctxt, ops, VCPU_SREG_DS);
3660 break;
3661 case 0xcb: /* ret far */
3662 rc = emulate_ret_far(ctxt, ops);
3663 break;
3664 case 0xcc: /* int3 */
3665 irq = 3;
3666 goto do_interrupt;
3667 case 0xcd: /* int n */
3668 irq = c->src.val;
3669 do_interrupt:
3670 rc = emulate_int(ctxt, ops, irq);
3671 break;
3672 case 0xce: /* into */
3673 if (ctxt->eflags & EFLG_OF) {
3674 irq = 4;
3675 goto do_interrupt;
3676 }
3677 break;
3678 case 0xcf: /* iret */
3679 rc = emulate_iret(ctxt, ops);
3680 break;
3681 case 0xd0 ... 0xd1: /* Grp2 */
3682 emulate_grp2(ctxt);
3683 break;
3684 case 0xd2 ... 0xd3: /* Grp2 */
3685 c->src.val = c->regs[VCPU_REGS_RCX];
3686 emulate_grp2(ctxt);
3687 break;
3688 case 0xe0 ... 0xe2: /* loop/loopz/loopnz */
3689 register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
3690 if (address_mask(c, c->regs[VCPU_REGS_RCX]) != 0 &&
3691 (c->b == 0xe2 || test_cc(c->b ^ 0x5, ctxt->eflags)))
3692 jmp_rel(c, c->src.val);
3693 break;
3694 case 0xe3: /* jcxz/jecxz/jrcxz */
3695 if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0)
3696 jmp_rel(c, c->src.val);
3697 break;
3698 case 0xe4: /* inb */
3699 case 0xe5: /* in */
3700 goto do_io_in;
3701 case 0xe6: /* outb */
3702 case 0xe7: /* out */
3703 goto do_io_out;
3704 case 0xe8: /* call (near) */ {
3705 long int rel = c->src.val;
3706 c->src.val = (unsigned long) c->eip;
3707 jmp_rel(c, rel);
3708 emulate_push(ctxt, ops);
3709 break;
3710 }
3711 case 0xe9: /* jmp rel */
3712 goto jmp;
3713 case 0xea: { /* jmp far */
3714 unsigned short sel;
3715 jump_far:
3716 memcpy(&sel, c->src.valptr + c->op_bytes, 2);
3717
3718 if (load_segment_descriptor(ctxt, ops, sel, VCPU_SREG_CS))
3719 goto done;
3720
3721 c->eip = 0;
3722 memcpy(&c->eip, c->src.valptr, c->op_bytes);
3723 break;
3724 }
3725 case 0xeb:
3726 jmp: /* jmp rel short */
3727 jmp_rel(c, c->src.val);
3728 c->dst.type = OP_NONE; /* Disable writeback. */
3729 break;
3730 case 0xec: /* in al,dx */
3731 case 0xed: /* in (e/r)ax,dx */
3732 c->src.val = c->regs[VCPU_REGS_RDX];
3733 do_io_in:
3734 c->dst.bytes = min(c->dst.bytes, 4u);
3735 if (!emulator_io_permited(ctxt, ops, c->src.val, c->dst.bytes)) {
3736 rc = emulate_gp(ctxt, 0);
3737 goto done;
3738 }
3739 if (!pio_in_emulated(ctxt, ops, c->dst.bytes, c->src.val,
3740 &c->dst.val))
3741 goto done; /* IO is needed */
3742 break;
3743 case 0xee: /* out dx,al */
3744 case 0xef: /* out dx,(e/r)ax */
3745 c->dst.val = c->regs[VCPU_REGS_RDX];
3746 do_io_out:
3747 c->src.bytes = min(c->src.bytes, 4u);
3748 if (!emulator_io_permited(ctxt, ops, c->dst.val,
3749 c->src.bytes)) {
3750 rc = emulate_gp(ctxt, 0);
3751 goto done;
3752 }
3753 ops->pio_out_emulated(c->src.bytes, c->dst.val,
3754 &c->src.val, 1, ctxt->vcpu);
3755 c->dst.type = OP_NONE; /* Disable writeback. */
3756 break;
3757 case 0xf4: /* hlt */
3758 ctxt->vcpu->arch.halt_request = 1;
3759 break;
3760 case 0xf5: /* cmc */
3761 /* complement carry flag from eflags reg */
3762 ctxt->eflags ^= EFLG_CF;
3763 break;
3764 case 0xf6 ... 0xf7: /* Grp3 */
3765 rc = emulate_grp3(ctxt, ops);
3766 break;
3767 case 0xf8: /* clc */
3768 ctxt->eflags &= ~EFLG_CF;
3769 break;
3770 case 0xf9: /* stc */
3771 ctxt->eflags |= EFLG_CF;
3772 break;
3773 case 0xfa: /* cli */
3774 if (emulator_bad_iopl(ctxt, ops)) {
3775 rc = emulate_gp(ctxt, 0);
3776 goto done;
3777 } else
3778 ctxt->eflags &= ~X86_EFLAGS_IF;
3779 break;
3780 case 0xfb: /* sti */
3781 if (emulator_bad_iopl(ctxt, ops)) {
3782 rc = emulate_gp(ctxt, 0);
3783 goto done;
3784 } else {
3785 ctxt->interruptibility = KVM_X86_SHADOW_INT_STI;
3786 ctxt->eflags |= X86_EFLAGS_IF;
3787 }
3788 break;
3789 case 0xfc: /* cld */
3790 ctxt->eflags &= ~EFLG_DF;
3791 break;
3792 case 0xfd: /* std */
3793 ctxt->eflags |= EFLG_DF;
3794 break;
3795 case 0xfe: /* Grp4 */
3796 grp45:
3797 rc = emulate_grp45(ctxt, ops);
3798 break;
3799 case 0xff: /* Grp5 */
3800 if (c->modrm_reg == 5)
3801 goto jump_far;
3802 goto grp45;
3803 default:
3804 goto cannot_emulate;
3805 }
3806
3807 if (rc != X86EMUL_CONTINUE)
3808 goto done;
3809
3810 writeback:
3811 rc = writeback(ctxt, ops);
3812 if (rc != X86EMUL_CONTINUE)
3813 goto done;
3814
3815 /*
3816 * restore dst type in case the decoding will be reused
3817 * (happens for string instruction )
3818 */
3819 c->dst.type = saved_dst_type;
3820
3821 if ((c->d & SrcMask) == SrcSI)
3822 string_addr_inc(ctxt, seg_override(ctxt, ops, c),
3823 VCPU_REGS_RSI, &c->src);
3824
3825 if ((c->d & DstMask) == DstDI)
3826 string_addr_inc(ctxt, VCPU_SREG_ES, VCPU_REGS_RDI,
3827 &c->dst);
3828
3829 if (c->rep_prefix && (c->d & String)) {
3830 struct read_cache *r = &ctxt->decode.io_read;
3831 register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
3832
3833 if (!string_insn_completed(ctxt)) {
3834 /*
3835 * Re-enter guest when pio read ahead buffer is empty
3836 * or, if it is not used, after each 1024 iteration.
3837 */
3838 if ((r->end != 0 || c->regs[VCPU_REGS_RCX] & 0x3ff) &&
3839 (r->end == 0 || r->end != r->pos)) {
3840 /*
3841 * Reset read cache. Usually happens before
3842 * decode, but since instruction is restarted
3843 * we have to do it here.
3844 */
3845 ctxt->decode.mem_read.end = 0;
3846 return EMULATION_RESTART;
3847 }
3848 goto done; /* skip rip writeback */
3849 }
3850 }
3851
3852 ctxt->eip = c->eip;
3853
3854 done:
3855 if (rc == X86EMUL_PROPAGATE_FAULT)
3856 ctxt->have_exception = true;
3857 if (rc == X86EMUL_INTERCEPTED)
3858 return EMULATION_INTERCEPTED;
3859
3860 return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK;
3861
3862 twobyte_insn:
3863 switch (c->b) {
3864 case 0x01: /* lgdt, lidt, lmsw */
3865 switch (c->modrm_reg) {
3866 u16 size;
3867 unsigned long address;
3868
3869 case 0: /* vmcall */
3870 if (c->modrm_mod != 3 || c->modrm_rm != 1)
3871 goto cannot_emulate;
3872
3873 rc = kvm_fix_hypercall(ctxt->vcpu);
3874 if (rc != X86EMUL_CONTINUE)
3875 goto done;
3876
3877 /* Let the processor re-execute the fixed hypercall */
3878 c->eip = ctxt->eip;
3879 /* Disable writeback. */
3880 c->dst.type = OP_NONE;
3881 break;
3882 case 2: /* lgdt */
3883 rc = read_descriptor(ctxt, ops, c->src.addr.mem,
3884 &size, &address, c->op_bytes);
3885 if (rc != X86EMUL_CONTINUE)
3886 goto done;
3887 realmode_lgdt(ctxt->vcpu, size, address);
3888 /* Disable writeback. */
3889 c->dst.type = OP_NONE;
3890 break;
3891 case 3: /* lidt/vmmcall */
3892 if (c->modrm_mod == 3) {
3893 switch (c->modrm_rm) {
3894 case 1:
3895 rc = kvm_fix_hypercall(ctxt->vcpu);
3896 break;
3897 default:
3898 goto cannot_emulate;
3899 }
3900 } else {
3901 rc = read_descriptor(ctxt, ops, c->src.addr.mem,
3902 &size, &address,
3903 c->op_bytes);
3904 if (rc != X86EMUL_CONTINUE)
3905 goto done;
3906 realmode_lidt(ctxt->vcpu, size, address);
3907 }
3908 /* Disable writeback. */
3909 c->dst.type = OP_NONE;
3910 break;
3911 case 4: /* smsw */
3912 c->dst.bytes = 2;
3913 c->dst.val = ops->get_cr(0, ctxt->vcpu);
3914 break;
3915 case 6: /* lmsw */
3916 ops->set_cr(0, (ops->get_cr(0, ctxt->vcpu) & ~0x0eul) |
3917 (c->src.val & 0x0f), ctxt->vcpu);
3918 c->dst.type = OP_NONE;
3919 break;
3920 case 5: /* not defined */
3921 emulate_ud(ctxt);
3922 rc = X86EMUL_PROPAGATE_FAULT;
3923 goto done;
3924 case 7: /* invlpg*/
3925 emulate_invlpg(ctxt->vcpu,
3926 linear(ctxt, c->src.addr.mem));
3927 /* Disable writeback. */
3928 c->dst.type = OP_NONE;
3929 break;
3930 default:
3931 goto cannot_emulate;
3932 }
3933 break;
3934 case 0x05: /* syscall */
3935 rc = emulate_syscall(ctxt, ops);
3936 break;
3937 case 0x06:
3938 emulate_clts(ctxt->vcpu);
3939 break;
3940 case 0x09: /* wbinvd */
3941 kvm_emulate_wbinvd(ctxt->vcpu);
3942 break;
3943 case 0x08: /* invd */
3944 case 0x0d: /* GrpP (prefetch) */
3945 case 0x18: /* Grp16 (prefetch/nop) */
3946 break;
3947 case 0x20: /* mov cr, reg */
3948 c->dst.val = ops->get_cr(c->modrm_reg, ctxt->vcpu);
3949 break;
3950 case 0x21: /* mov from dr to reg */
3951 ops->get_dr(c->modrm_reg, &c->dst.val, ctxt->vcpu);
3952 break;
3953 case 0x22: /* mov reg, cr */
3954 if (ops->set_cr(c->modrm_reg, c->src.val, ctxt->vcpu)) {
3955 emulate_gp(ctxt, 0);
3956 rc = X86EMUL_PROPAGATE_FAULT;
3957 goto done;
3958 }
3959 c->dst.type = OP_NONE;
3960 break;
3961 case 0x23: /* mov from reg to dr */
3962 if (ops->set_dr(c->modrm_reg, c->src.val &
3963 ((ctxt->mode == X86EMUL_MODE_PROT64) ?
3964 ~0ULL : ~0U), ctxt->vcpu) < 0) {
3965 /* #UD condition is already handled by the code above */
3966 emulate_gp(ctxt, 0);
3967 rc = X86EMUL_PROPAGATE_FAULT;
3968 goto done;
3969 }
3970
3971 c->dst.type = OP_NONE; /* no writeback */
3972 break;
3973 case 0x30:
3974 /* wrmsr */
3975 msr_data = (u32)c->regs[VCPU_REGS_RAX]
3976 | ((u64)c->regs[VCPU_REGS_RDX] << 32);
3977 if (ops->set_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], msr_data)) {
3978 emulate_gp(ctxt, 0);
3979 rc = X86EMUL_PROPAGATE_FAULT;
3980 goto done;
3981 }
3982 rc = X86EMUL_CONTINUE;
3983 break;
3984 case 0x32:
3985 /* rdmsr */
3986 if (ops->get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data)) {
3987 emulate_gp(ctxt, 0);
3988 rc = X86EMUL_PROPAGATE_FAULT;
3989 goto done;
3990 } else {
3991 c->regs[VCPU_REGS_RAX] = (u32)msr_data;
3992 c->regs[VCPU_REGS_RDX] = msr_data >> 32;
3993 }
3994 rc = X86EMUL_CONTINUE;
3995 break;
3996 case 0x34: /* sysenter */
3997 rc = emulate_sysenter(ctxt, ops);
3998 break;
3999 case 0x35: /* sysexit */
4000 rc = emulate_sysexit(ctxt, ops);
4001 break;
4002 case 0x40 ... 0x4f: /* cmov */
4003 c->dst.val = c->dst.orig_val = c->src.val;
4004 if (!test_cc(c->b, ctxt->eflags))
4005 c->dst.type = OP_NONE; /* no writeback */
4006 break;
4007 case 0x80 ... 0x8f: /* jnz rel, etc*/
4008 if (test_cc(c->b, ctxt->eflags))
4009 jmp_rel(c, c->src.val);
4010 break;
4011 case 0x90 ... 0x9f: /* setcc r/m8 */
4012 c->dst.val = test_cc(c->b, ctxt->eflags);
4013 break;
4014 case 0xa0: /* push fs */
4015 emulate_push_sreg(ctxt, ops, VCPU_SREG_FS);
4016 break;
4017 case 0xa1: /* pop fs */
4018 rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_FS);
4019 break;
4020 case 0xa3:
4021 bt: /* bt */
4022 c->dst.type = OP_NONE;
4023 /* only subword offset */
4024 c->src.val &= (c->dst.bytes << 3) - 1;
4025 emulate_2op_SrcV_nobyte("bt", c->src, c->dst, ctxt->eflags);
4026 break;
4027 case 0xa4: /* shld imm8, r, r/m */
4028 case 0xa5: /* shld cl, r, r/m */
4029 emulate_2op_cl("shld", c->src2, c->src, c->dst, ctxt->eflags);
4030 break;
4031 case 0xa8: /* push gs */
4032 emulate_push_sreg(ctxt, ops, VCPU_SREG_GS);
4033 break;
4034 case 0xa9: /* pop gs */
4035 rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_GS);
4036 break;
4037 case 0xab:
4038 bts: /* bts */
4039 emulate_2op_SrcV_nobyte("bts", c->src, c->dst, ctxt->eflags);
4040 break;
4041 case 0xac: /* shrd imm8, r, r/m */
4042 case 0xad: /* shrd cl, r, r/m */
4043 emulate_2op_cl("shrd", c->src2, c->src, c->dst, ctxt->eflags);
4044 break;
4045 case 0xae: /* clflush */
4046 break;
4047 case 0xb0 ... 0xb1: /* cmpxchg */
4048 /*
4049 * Save real source value, then compare EAX against
4050 * destination.
4051 */
4052 c->src.orig_val = c->src.val;
4053 c->src.val = c->regs[VCPU_REGS_RAX];
4054 emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
4055 if (ctxt->eflags & EFLG_ZF) {
4056 /* Success: write back to memory. */
4057 c->dst.val = c->src.orig_val;
4058 } else {
4059 /* Failure: write the value we saw to EAX. */
4060 c->dst.type = OP_REG;
4061 c->dst.addr.reg = (unsigned long *)&c->regs[VCPU_REGS_RAX];
4062 }
4063 break;
4064 case 0xb2: /* lss */
4065 rc = emulate_load_segment(ctxt, ops, VCPU_SREG_SS);
4066 break;
4067 case 0xb3:
4068 btr: /* btr */
4069 emulate_2op_SrcV_nobyte("btr", c->src, c->dst, ctxt->eflags);
4070 break;
4071 case 0xb4: /* lfs */
4072 rc = emulate_load_segment(ctxt, ops, VCPU_SREG_FS);
4073 break;
4074 case 0xb5: /* lgs */
4075 rc = emulate_load_segment(ctxt, ops, VCPU_SREG_GS);
4076 break;
4077 case 0xb6 ... 0xb7: /* movzx */
4078 c->dst.bytes = c->op_bytes;
4079 c->dst.val = (c->d & ByteOp) ? (u8) c->src.val
4080 : (u16) c->src.val;
4081 break;
4082 case 0xba: /* Grp8 */
4083 switch (c->modrm_reg & 3) {
4084 case 0:
4085 goto bt;
4086 case 1:
4087 goto bts;
4088 case 2:
4089 goto btr;
4090 case 3:
4091 goto btc;
4092 }
4093 break;
4094 case 0xbb:
4095 btc: /* btc */
4096 emulate_2op_SrcV_nobyte("btc", c->src, c->dst, ctxt->eflags);
4097 break;
4098 case 0xbc: { /* bsf */
4099 u8 zf;
4100 __asm__ ("bsf %2, %0; setz %1"
4101 : "=r"(c->dst.val), "=q"(zf)
4102 : "r"(c->src.val));
4103 ctxt->eflags &= ~X86_EFLAGS_ZF;
4104 if (zf) {
4105 ctxt->eflags |= X86_EFLAGS_ZF;
4106 c->dst.type = OP_NONE; /* Disable writeback. */
4107 }
4108 break;
4109 }
4110 case 0xbd: { /* bsr */
4111 u8 zf;
4112 __asm__ ("bsr %2, %0; setz %1"
4113 : "=r"(c->dst.val), "=q"(zf)
4114 : "r"(c->src.val));
4115 ctxt->eflags &= ~X86_EFLAGS_ZF;
4116 if (zf) {
4117 ctxt->eflags |= X86_EFLAGS_ZF;
4118 c->dst.type = OP_NONE; /* Disable writeback. */
4119 }
4120 break;
4121 }
4122 case 0xbe ... 0xbf: /* movsx */
4123 c->dst.bytes = c->op_bytes;
4124 c->dst.val = (c->d & ByteOp) ? (s8) c->src.val :
4125 (s16) c->src.val;
4126 break;
4127 case 0xc0 ... 0xc1: /* xadd */
4128 emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
4129 /* Write back the register source. */
4130 c->src.val = c->dst.orig_val;
4131 write_register_operand(&c->src);
4132 break;
4133 case 0xc3: /* movnti */
4134 c->dst.bytes = c->op_bytes;
4135 c->dst.val = (c->op_bytes == 4) ? (u32) c->src.val :
4136 (u64) c->src.val;
4137 break;
4138 case 0xc7: /* Grp9 (cmpxchg8b) */
4139 rc = emulate_grp9(ctxt, ops);
4140 break;
4141 default:
4142 goto cannot_emulate;
4143 }
4144
4145 if (rc != X86EMUL_CONTINUE)
4146 goto done;
4147
4148 goto writeback;
4149
4150 cannot_emulate:
4151 return -1;
4152 }
Linux kernel - Deliverables
This page took 0.190547 seconds and 5 git commands to generate.