linux/arch/arm/kernel/kprobes-arm.c
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   1/*
   2 * arch/arm/kernel/kprobes-decode.c
   3 *
   4 * Copyright (C) 2006, 2007 Motorola Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License for more details.
  14 */
  15
  16/*
  17 * We do not have hardware single-stepping on ARM, This
  18 * effort is further complicated by the ARM not having a
  19 * "next PC" register.  Instructions that change the PC
  20 * can't be safely single-stepped in a MP environment, so
  21 * we have a lot of work to do:
  22 *
  23 * In the prepare phase:
  24 *   *) If it is an instruction that does anything
  25 *      with the CPU mode, we reject it for a kprobe.
  26 *      (This is out of laziness rather than need.  The
  27 *      instructions could be simulated.)
  28 *
  29 *   *) Otherwise, decode the instruction rewriting its
  30 *      registers to take fixed, ordered registers and
  31 *      setting a handler for it to run the instruction.
  32 *
  33 * In the execution phase by an instruction's handler:
  34 *
  35 *   *) If the PC is written to by the instruction, the
  36 *      instruction must be fully simulated in software.
  37 *
  38 *   *) Otherwise, a modified form of the instruction is
  39 *      directly executed.  Its handler calls the
  40 *      instruction in insn[0].  In insn[1] is a
  41 *      "mov pc, lr" to return.
  42 *
  43 *      Before calling, load up the reordered registers
  44 *      from the original instruction's registers.  If one
  45 *      of the original input registers is the PC, compute
  46 *      and adjust the appropriate input register.
  47 *
  48 *      After call completes, copy the output registers to
  49 *      the original instruction's original registers.
  50 *
  51 * We don't use a real breakpoint instruction since that
  52 * would have us in the kernel go from SVC mode to SVC
  53 * mode losing the link register.  Instead we use an
  54 * undefined instruction.  To simplify processing, the
  55 * undefined instruction used for kprobes must be reserved
  56 * exclusively for kprobes use.
  57 *
  58 * TODO: ifdef out some instruction decoding based on architecture.
  59 */
  60
  61#include <linux/kernel.h>
  62#include <linux/kprobes.h>
  63#include <linux/module.h>
  64
  65#include "kprobes.h"
  66
  67#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
  68
  69#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
  70
  71#if  __LINUX_ARM_ARCH__ >= 6
  72#define BLX(reg)        "blx    "reg"           \n\t"
  73#else
  74#define BLX(reg)        "mov    lr, pc          \n\t"   \
  75                        "mov    pc, "reg"       \n\t"
  76#endif
  77
  78/*
  79 * To avoid the complications of mimicing single-stepping on a
  80 * processor without a Next-PC or a single-step mode, and to
  81 * avoid having to deal with the side-effects of boosting, we
  82 * simulate or emulate (almost) all ARM instructions.
  83 *
  84 * "Simulation" is where the instruction's behavior is duplicated in
  85 * C code.  "Emulation" is where the original instruction is rewritten
  86 * and executed, often by altering its registers.
  87 *
  88 * By having all behavior of the kprobe'd instruction completed before
  89 * returning from the kprobe_handler(), all locks (scheduler and
  90 * interrupt) can safely be released.  There is no need for secondary
  91 * breakpoints, no race with MP or preemptable kernels, nor having to
  92 * clean up resources counts at a later time impacting overall system
  93 * performance.  By rewriting the instruction, only the minimum registers
  94 * need to be loaded and saved back optimizing performance.
  95 *
  96 * Calling the insnslot_*_rwflags version of a function doesn't hurt
  97 * anything even when the CPSR flags aren't updated by the
  98 * instruction.  It's just a little slower in return for saving
  99 * a little space by not having a duplicate function that doesn't
 100 * update the flags.  (The same optimization can be said for
 101 * instructions that do or don't perform register writeback)
 102 * Also, instructions can either read the flags, only write the
 103 * flags, or read and write the flags.  To save combinations
 104 * rather than for sheer performance, flag functions just assume
 105 * read and write of flags.
 106 */
 107
 108static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)
 109{
 110        kprobe_opcode_t insn = p->opcode;
 111        long iaddr = (long)p->addr;
 112        int disp  = branch_displacement(insn);
 113
 114        if (insn & (1 << 24))
 115                regs->ARM_lr = iaddr + 4;
 116
 117        regs->ARM_pc = iaddr + 8 + disp;
 118}
 119
 120static void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs)
 121{
 122        kprobe_opcode_t insn = p->opcode;
 123        long iaddr = (long)p->addr;
 124        int disp = branch_displacement(insn);
 125
 126        regs->ARM_lr = iaddr + 4;
 127        regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
 128        regs->ARM_cpsr |= PSR_T_BIT;
 129}
 130
 131static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)
 132{
 133        kprobe_opcode_t insn = p->opcode;
 134        int rm = insn & 0xf;
 135        long rmv = regs->uregs[rm];
 136
 137        if (insn & (1 << 5))
 138                regs->ARM_lr = (long)p->addr + 4;
 139
 140        regs->ARM_pc = rmv & ~0x1;
 141        regs->ARM_cpsr &= ~PSR_T_BIT;
 142        if (rmv & 0x1)
 143                regs->ARM_cpsr |= PSR_T_BIT;
 144}
 145
 146static void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs)
 147{
 148        kprobe_opcode_t insn = p->opcode;
 149        int rd = (insn >> 12) & 0xf;
 150        unsigned long mask = 0xf8ff03df; /* Mask out execution state */
 151        regs->uregs[rd] = regs->ARM_cpsr & mask;
 152}
 153
 154static void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs)
 155{
 156        regs->uregs[12] = regs->uregs[13];
 157}
 158
 159static void __kprobes
 160emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs)
 161{
 162        kprobe_opcode_t insn = p->opcode;
 163        unsigned long pc = (unsigned long)p->addr + 8;
 164        int rt = (insn >> 12) & 0xf;
 165        int rn = (insn >> 16) & 0xf;
 166        int rm = insn & 0xf;
 167
 168        register unsigned long rtv asm("r0") = regs->uregs[rt];
 169        register unsigned long rt2v asm("r1") = regs->uregs[rt+1];
 170        register unsigned long rnv asm("r2") = (rn == 15) ? pc
 171                                                          : regs->uregs[rn];
 172        register unsigned long rmv asm("r3") = regs->uregs[rm];
 173
 174        __asm__ __volatile__ (
 175                BLX("%[fn]")
 176                : "=r" (rtv), "=r" (rt2v), "=r" (rnv)
 177                : "0" (rtv), "1" (rt2v), "2" (rnv), "r" (rmv),
 178                  [fn] "r" (p->ainsn.insn_fn)
 179                : "lr", "memory", "cc"
 180        );
 181
 182        regs->uregs[rt] = rtv;
 183        regs->uregs[rt+1] = rt2v;
 184        if (is_writeback(insn))
 185                regs->uregs[rn] = rnv;
 186}
 187
 188static void __kprobes
 189emulate_ldr(struct kprobe *p, struct pt_regs *regs)
 190{
 191        kprobe_opcode_t insn = p->opcode;
 192        unsigned long pc = (unsigned long)p->addr + 8;
 193        int rt = (insn >> 12) & 0xf;
 194        int rn = (insn >> 16) & 0xf;
 195        int rm = insn & 0xf;
 196
 197        register unsigned long rtv asm("r0");
 198        register unsigned long rnv asm("r2") = (rn == 15) ? pc
 199                                                          : regs->uregs[rn];
 200        register unsigned long rmv asm("r3") = regs->uregs[rm];
 201
 202        __asm__ __volatile__ (
 203                BLX("%[fn]")
 204                : "=r" (rtv), "=r" (rnv)
 205                : "1" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
 206                : "lr", "memory", "cc"
 207        );
 208
 209        if (rt == 15)
 210                load_write_pc(rtv, regs);
 211        else
 212                regs->uregs[rt] = rtv;
 213
 214        if (is_writeback(insn))
 215                regs->uregs[rn] = rnv;
 216}
 217
 218static void __kprobes
 219emulate_str(struct kprobe *p, struct pt_regs *regs)
 220{
 221        kprobe_opcode_t insn = p->opcode;
 222        unsigned long rtpc = (unsigned long)p->addr + str_pc_offset;
 223        unsigned long rnpc = (unsigned long)p->addr + 8;
 224        int rt = (insn >> 12) & 0xf;
 225        int rn = (insn >> 16) & 0xf;
 226        int rm = insn & 0xf;
 227
 228        register unsigned long rtv asm("r0") = (rt == 15) ? rtpc
 229                                                          : regs->uregs[rt];
 230        register unsigned long rnv asm("r2") = (rn == 15) ? rnpc
 231                                                          : regs->uregs[rn];
 232        register unsigned long rmv asm("r3") = regs->uregs[rm];
 233
 234        __asm__ __volatile__ (
 235                BLX("%[fn]")
 236                : "=r" (rnv)
 237                : "r" (rtv), "0" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
 238                : "lr", "memory", "cc"
 239        );
 240
 241        if (is_writeback(insn))
 242                regs->uregs[rn] = rnv;
 243}
 244
 245static void __kprobes
 246emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs)
 247{
 248        kprobe_opcode_t insn = p->opcode;
 249        unsigned long pc = (unsigned long)p->addr + 8;
 250        int rd = (insn >> 12) & 0xf;
 251        int rn = (insn >> 16) & 0xf;
 252        int rm = insn & 0xf;
 253        int rs = (insn >> 8) & 0xf;
 254
 255        register unsigned long rdv asm("r0") = regs->uregs[rd];
 256        register unsigned long rnv asm("r2") = (rn == 15) ? pc
 257                                                          : regs->uregs[rn];
 258        register unsigned long rmv asm("r3") = (rm == 15) ? pc
 259                                                          : regs->uregs[rm];
 260        register unsigned long rsv asm("r1") = regs->uregs[rs];
 261        unsigned long cpsr = regs->ARM_cpsr;
 262
 263        __asm__ __volatile__ (
 264                "msr    cpsr_fs, %[cpsr]        \n\t"
 265                BLX("%[fn]")
 266                "mrs    %[cpsr], cpsr           \n\t"
 267                : "=r" (rdv), [cpsr] "=r" (cpsr)
 268                : "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
 269                  "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
 270                : "lr", "memory", "cc"
 271        );
 272
 273        if (rd == 15)
 274                alu_write_pc(rdv, regs);
 275        else
 276                regs->uregs[rd] = rdv;
 277        regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
 278}
 279
 280static void __kprobes
 281emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
 282{
 283        kprobe_opcode_t insn = p->opcode;
 284        int rd = (insn >> 12) & 0xf;
 285        int rn = (insn >> 16) & 0xf;
 286        int rm = insn & 0xf;
 287
 288        register unsigned long rdv asm("r0") = regs->uregs[rd];
 289        register unsigned long rnv asm("r2") = regs->uregs[rn];
 290        register unsigned long rmv asm("r3") = regs->uregs[rm];
 291        unsigned long cpsr = regs->ARM_cpsr;
 292
 293        __asm__ __volatile__ (
 294                "msr    cpsr_fs, %[cpsr]        \n\t"
 295                BLX("%[fn]")
 296                "mrs    %[cpsr], cpsr           \n\t"
 297                : "=r" (rdv), [cpsr] "=r" (cpsr)
 298                : "0" (rdv), "r" (rnv), "r" (rmv),
 299                  "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
 300                : "lr", "memory", "cc"
 301        );
 302
 303        regs->uregs[rd] = rdv;
 304        regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
 305}
 306
 307static void __kprobes
 308emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
 309{
 310        kprobe_opcode_t insn = p->opcode;
 311        int rd = (insn >> 16) & 0xf;
 312        int rn = (insn >> 12) & 0xf;
 313        int rm = insn & 0xf;
 314        int rs = (insn >> 8) & 0xf;
 315
 316        register unsigned long rdv asm("r2") = regs->uregs[rd];
 317        register unsigned long rnv asm("r0") = regs->uregs[rn];
 318        register unsigned long rmv asm("r3") = regs->uregs[rm];
 319        register unsigned long rsv asm("r1") = regs->uregs[rs];
 320        unsigned long cpsr = regs->ARM_cpsr;
 321
 322        __asm__ __volatile__ (
 323                "msr    cpsr_fs, %[cpsr]        \n\t"
 324                BLX("%[fn]")
 325                "mrs    %[cpsr], cpsr           \n\t"
 326                : "=r" (rdv), [cpsr] "=r" (cpsr)
 327                : "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
 328                  "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
 329                : "lr", "memory", "cc"
 330        );
 331
 332        regs->uregs[rd] = rdv;
 333        regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
 334}
 335
 336static void __kprobes
 337emulate_rd12rm0_noflags_nopc(struct kprobe *p, struct pt_regs *regs)
 338{
 339        kprobe_opcode_t insn = p->opcode;
 340        int rd = (insn >> 12) & 0xf;
 341        int rm = insn & 0xf;
 342
 343        register unsigned long rdv asm("r0") = regs->uregs[rd];
 344        register unsigned long rmv asm("r3") = regs->uregs[rm];
 345
 346        __asm__ __volatile__ (
 347                BLX("%[fn]")
 348                : "=r" (rdv)
 349                : "0" (rdv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
 350                : "lr", "memory", "cc"
 351        );
 352
 353        regs->uregs[rd] = rdv;
 354}
 355
 356static void __kprobes
 357emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
 358{
 359        kprobe_opcode_t insn = p->opcode;
 360        int rdlo = (insn >> 12) & 0xf;
 361        int rdhi = (insn >> 16) & 0xf;
 362        int rn = insn & 0xf;
 363        int rm = (insn >> 8) & 0xf;
 364
 365        register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
 366        register unsigned long rdhiv asm("r2") = regs->uregs[rdhi];
 367        register unsigned long rnv asm("r3") = regs->uregs[rn];
 368        register unsigned long rmv asm("r1") = regs->uregs[rm];
 369        unsigned long cpsr = regs->ARM_cpsr;
 370
 371        __asm__ __volatile__ (
 372                "msr    cpsr_fs, %[cpsr]        \n\t"
 373                BLX("%[fn]")
 374                "mrs    %[cpsr], cpsr           \n\t"
 375                : "=r" (rdlov), "=r" (rdhiv), [cpsr] "=r" (cpsr)
 376                : "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
 377                  "2" (cpsr), [fn] "r" (p->ainsn.insn_fn)
 378                : "lr", "memory", "cc"
 379        );
 380
 381        regs->uregs[rdlo] = rdlov;
 382        regs->uregs[rdhi] = rdhiv;
 383        regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
 384}
 385
 386/*
 387 * For the instruction masking and comparisons in all the "space_*"
 388 * functions below, Do _not_ rearrange the order of tests unless
 389 * you're very, very sure of what you are doing.  For the sake of
 390 * efficiency, the masks for some tests sometimes assume other test
 391 * have been done prior to them so the number of patterns to test
 392 * for an instruction set can be as broad as possible to reduce the
 393 * number of tests needed.
 394 */
 395
 396static const union decode_item arm_1111_table[] = {
 397        /* Unconditional instructions                                   */
 398
 399        /* memory hint          1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
 400        /* PLDI (immediate)     1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
 401        /* PLDW (immediate)     1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
 402        /* PLD (immediate)      1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
 403        DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop),
 404
 405        /* memory hint          1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */
 406        /* PLDI (register)      1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */
 407        /* PLDW (register)      1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */
 408        /* PLD (register)       1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */
 409        DECODE_SIMULATE (0xfe300010, 0xf6100000, kprobe_simulate_nop),
 410
 411        /* BLX (immediate)      1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
 412        DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1),
 413
 414        /* CPS                  1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
 415        /* SETEND               1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
 416        /* SRS                  1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
 417        /* RFE                  1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
 418
 419        /* Coprocessor instructions... */
 420        /* MCRR2                1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
 421        /* MRRC2                1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
 422        /* LDC2                 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
 423        /* STC2                 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
 424        /* CDP2                 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
 425        /* MCR2                 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
 426        /* MRC2                 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
 427
 428        /* Other unallocated instructions...                            */
 429        DECODE_END
 430};
 431
 432static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
 433        /* Miscellaneous instructions                                   */
 434
 435        /* MRS cpsr             cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
 436        DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs,
 437                                                 REGS(0, NOPC, 0, 0, 0)),
 438
 439        /* BX                   cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
 440        DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx),
 441
 442        /* BLX (register)       cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
 443        DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx,
 444                                                 REGS(0, 0, 0, 0, NOPC)),
 445
 446        /* CLZ                  cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
 447        DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc,
 448                                                 REGS(0, NOPC, 0, 0, NOPC)),
 449
 450        /* QADD                 cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
 451        /* QSUB                 cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
 452        /* QDADD                cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
 453        /* QDSUB                cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
 454        DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc,
 455                                                 REGS(NOPC, NOPC, 0, 0, NOPC)),
 456
 457        /* BXJ                  cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
 458        /* MSR                  cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
 459        /* MRS spsr             cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
 460        /* BKPT                 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
 461        /* SMC                  cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
 462        /* And unallocated instructions...                              */
 463        DECODE_END
 464};
 465
 466static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
 467        /* Halfword multiply and multiply-accumulate                    */
 468
 469        /* SMLALxy              cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
 470        DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
 471                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 472
 473        /* SMULWy               cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
 474        DECODE_OR       (0x0ff000b0, 0x012000a0),
 475        /* SMULxy               cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
 476        DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc,
 477                                                 REGS(NOPC, 0, NOPC, 0, NOPC)),
 478
 479        /* SMLAxy               cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
 480        DECODE_OR       (0x0ff00090, 0x01000080),
 481        /* SMLAWy               cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
 482        DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc,
 483                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 484
 485        DECODE_END
 486};
 487
 488static const union decode_item arm_cccc_0000_____1001_table[] = {
 489        /* Multiply and multiply-accumulate                             */
 490
 491        /* MUL                  cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
 492        /* MULS                 cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
 493        DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc,
 494                                                 REGS(NOPC, 0, NOPC, 0, NOPC)),
 495
 496        /* MLA                  cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
 497        /* MLAS                 cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
 498        DECODE_OR       (0x0fe000f0, 0x00200090),
 499        /* MLS                  cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
 500        DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc,
 501                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 502
 503        /* UMAAL                cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
 504        DECODE_OR       (0x0ff000f0, 0x00400090),
 505        /* UMULL                cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
 506        /* UMULLS               cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
 507        /* UMLAL                cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
 508        /* UMLALS               cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
 509        /* SMULL                cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
 510        /* SMULLS               cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
 511        /* SMLAL                cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
 512        /* SMLALS               cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
 513        DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
 514                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 515
 516        DECODE_END
 517};
 518
 519static const union decode_item arm_cccc_0001_____1001_table[] = {
 520        /* Synchronization primitives                                   */
 521
 522#if __LINUX_ARM_ARCH__ < 6
 523        /* Deprecated on ARMv6 and may be UNDEFINED on v7               */
 524        /* SMP/SWPB             cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
 525        DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc,
 526                                                 REGS(NOPC, NOPC, 0, 0, NOPC)),
 527#endif
 528        /* LDREX/STREX{,D,B,H}  cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
 529        /* And unallocated instructions...                              */
 530        DECODE_END
 531};
 532
 533static const union decode_item arm_cccc_000x_____1xx1_table[] = {
 534        /* Extra load/store instructions                                */
 535
 536        /* STRHT                cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
 537        /* ???                  cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
 538        /* LDRHT                cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
 539        /* LDRSBT               cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
 540        /* LDRSHT               cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
 541        DECODE_REJECT   (0x0f200090, 0x00200090),
 542
 543        /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
 544        DECODE_REJECT   (0x0e10e0d0, 0x0000e0d0),
 545
 546        /* LDRD (register)      cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
 547        /* STRD (register)      cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
 548        DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd,
 549                                                 REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
 550
 551        /* LDRD (immediate)     cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
 552        /* STRD (immediate)     cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
 553        DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd,
 554                                                 REGS(NOPCWB, NOPCX, 0, 0, 0)),
 555
 556        /* STRH (register)      cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
 557        DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str,
 558                                                 REGS(NOPCWB, NOPC, 0, 0, NOPC)),
 559
 560        /* LDRH (register)      cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
 561        /* LDRSB (register)     cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
 562        /* LDRSH (register)     cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
 563        DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr,
 564                                                 REGS(NOPCWB, NOPC, 0, 0, NOPC)),
 565
 566        /* STRH (immediate)     cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
 567        DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str,
 568                                                 REGS(NOPCWB, NOPC, 0, 0, 0)),
 569
 570        /* LDRH (immediate)     cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
 571        /* LDRSB (immediate)    cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
 572        /* LDRSH (immediate)    cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
 573        DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr,
 574                                                 REGS(NOPCWB, NOPC, 0, 0, 0)),
 575
 576        DECODE_END
 577};
 578
 579static const union decode_item arm_cccc_000x_table[] = {
 580        /* Data-processing (register)                                   */
 581
 582        /* <op>S PC, ...        cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
 583        DECODE_REJECT   (0x0e10f000, 0x0010f000),
 584
 585        /* MOV IP, SP           1110 0001 1010 0000 1100 0000 0000 1101 */
 586        DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp),
 587
 588        /* TST (register)       cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
 589        /* TEQ (register)       cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
 590        /* CMP (register)       cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
 591        /* CMN (register)       cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
 592        DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags,
 593                                                 REGS(ANY, 0, 0, 0, ANY)),
 594
 595        /* MOV (register)       cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
 596        /* MVN (register)       cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
 597        DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags,
 598                                                 REGS(0, ANY, 0, 0, ANY)),
 599
 600        /* AND (register)       cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
 601        /* EOR (register)       cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
 602        /* SUB (register)       cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
 603        /* RSB (register)       cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
 604        /* ADD (register)       cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
 605        /* ADC (register)       cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
 606        /* SBC (register)       cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
 607        /* RSC (register)       cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
 608        /* ORR (register)       cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
 609        /* BIC (register)       cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
 610        DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags,
 611                                                 REGS(ANY, ANY, 0, 0, ANY)),
 612
 613        /* TST (reg-shift reg)  cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
 614        /* TEQ (reg-shift reg)  cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
 615        /* CMP (reg-shift reg)  cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
 616        /* CMN (reg-shift reg)  cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
 617        DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags,
 618                                                 REGS(ANY, 0, NOPC, 0, ANY)),
 619
 620        /* MOV (reg-shift reg)  cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
 621        /* MVN (reg-shift reg)  cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
 622        DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags,
 623                                                 REGS(0, ANY, NOPC, 0, ANY)),
 624
 625        /* AND (reg-shift reg)  cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
 626        /* EOR (reg-shift reg)  cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
 627        /* SUB (reg-shift reg)  cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
 628        /* RSB (reg-shift reg)  cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
 629        /* ADD (reg-shift reg)  cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
 630        /* ADC (reg-shift reg)  cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
 631        /* SBC (reg-shift reg)  cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
 632        /* RSC (reg-shift reg)  cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
 633        /* ORR (reg-shift reg)  cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
 634        /* BIC (reg-shift reg)  cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
 635        DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
 636                                                 REGS(ANY, ANY, NOPC, 0, ANY)),
 637
 638        DECODE_END
 639};
 640
 641static const union decode_item arm_cccc_001x_table[] = {
 642        /* Data-processing (immediate)                                  */
 643
 644        /* MOVW                 cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
 645        /* MOVT                 cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
 646        DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc,
 647                                                 REGS(0, NOPC, 0, 0, 0)),
 648
 649        /* YIELD                cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
 650        DECODE_OR       (0x0fff00ff, 0x03200001),
 651        /* SEV                  cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
 652        DECODE_EMULATE  (0x0fff00ff, 0x03200004, kprobe_emulate_none),
 653        /* NOP                  cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
 654        /* WFE                  cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
 655        /* WFI                  cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
 656        DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop),
 657        /* DBG                  cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
 658        /* unallocated hints    cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
 659        /* MSR (immediate)      cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
 660        DECODE_REJECT   (0x0fb00000, 0x03200000),
 661
 662        /* <op>S PC, ...        cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
 663        DECODE_REJECT   (0x0e10f000, 0x0210f000),
 664
 665        /* TST (immediate)      cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
 666        /* TEQ (immediate)      cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
 667        /* CMP (immediate)      cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
 668        /* CMN (immediate)      cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
 669        DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
 670                                                 REGS(ANY, 0, 0, 0, 0)),
 671
 672        /* MOV (immediate)      cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
 673        /* MVN (immediate)      cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
 674        DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
 675                                                 REGS(0, ANY, 0, 0, 0)),
 676
 677        /* AND (immediate)      cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
 678        /* EOR (immediate)      cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
 679        /* SUB (immediate)      cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
 680        /* RSB (immediate)      cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
 681        /* ADD (immediate)      cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
 682        /* ADC (immediate)      cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
 683        /* SBC (immediate)      cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
 684        /* RSC (immediate)      cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
 685        /* ORR (immediate)      cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
 686        /* BIC (immediate)      cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
 687        DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
 688                                                 REGS(ANY, ANY, 0, 0, 0)),
 689
 690        DECODE_END
 691};
 692
 693static const union decode_item arm_cccc_0110_____xxx1_table[] = {
 694        /* Media instructions                                           */
 695
 696        /* SEL                  cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
 697        DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc,
 698                                                 REGS(NOPC, NOPC, 0, 0, NOPC)),
 699
 700        /* SSAT                 cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
 701        /* USAT                 cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
 702        DECODE_OR(0x0fa00030, 0x06a00010),
 703        /* SSAT16               cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
 704        /* USAT16               cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
 705        DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc,
 706                                                 REGS(0, NOPC, 0, 0, NOPC)),
 707
 708        /* REV                  cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
 709        /* REV16                cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
 710        /* RBIT                 cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
 711        /* REVSH                cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
 712        DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc,
 713                                                 REGS(0, NOPC, 0, 0, NOPC)),
 714
 715        /* ???                  cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
 716        DECODE_REJECT   (0x0fb00010, 0x06000010),
 717        /* ???                  cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
 718        DECODE_REJECT   (0x0f8000f0, 0x060000b0),
 719        /* ???                  cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
 720        DECODE_REJECT   (0x0f8000f0, 0x060000d0),
 721        /* SADD16               cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
 722        /* SADDSUBX             cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
 723        /* SSUBADDX             cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
 724        /* SSUB16               cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
 725        /* SADD8                cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
 726        /* SSUB8                cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
 727        /* QADD16               cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
 728        /* QADDSUBX             cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
 729        /* QSUBADDX             cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
 730        /* QSUB16               cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
 731        /* QADD8                cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
 732        /* QSUB8                cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
 733        /* SHADD16              cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
 734        /* SHADDSUBX            cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
 735        /* SHSUBADDX            cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
 736        /* SHSUB16              cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
 737        /* SHADD8               cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
 738        /* SHSUB8               cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
 739        /* UADD16               cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
 740        /* UADDSUBX             cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
 741        /* USUBADDX             cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
 742        /* USUB16               cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
 743        /* UADD8                cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
 744        /* USUB8                cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
 745        /* UQADD16              cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
 746        /* UQADDSUBX            cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
 747        /* UQSUBADDX            cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
 748        /* UQSUB16              cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
 749        /* UQADD8               cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
 750        /* UQSUB8               cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
 751        /* UHADD16              cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
 752        /* UHADDSUBX            cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
 753        /* UHSUBADDX            cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
 754        /* UHSUB16              cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
 755        /* UHADD8               cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
 756        /* UHSUB8               cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
 757        DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc,
 758                                                 REGS(NOPC, NOPC, 0, 0, NOPC)),
 759
 760        /* PKHBT                cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
 761        /* PKHTB                cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
 762        DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc,
 763                                                 REGS(NOPC, NOPC, 0, 0, NOPC)),
 764
 765        /* ???                  cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
 766        /* ???                  cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
 767        DECODE_REJECT   (0x0fb000f0, 0x06900070),
 768
 769        /* SXTB16               cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
 770        /* SXTB                 cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
 771        /* SXTH                 cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
 772        /* UXTB16               cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
 773        /* UXTB                 cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
 774        /* UXTH                 cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
 775        DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc,
 776                                                 REGS(0, NOPC, 0, 0, NOPC)),
 777
 778        /* SXTAB16              cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
 779        /* SXTAB                cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
 780        /* SXTAH                cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
 781        /* UXTAB16              cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
 782        /* UXTAB                cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
 783        /* UXTAH                cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
 784        DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc,
 785                                                 REGS(NOPCX, NOPC, 0, 0, NOPC)),
 786
 787        DECODE_END
 788};
 789
 790static const union decode_item arm_cccc_0111_____xxx1_table[] = {
 791        /* Media instructions                                           */
 792
 793        /* UNDEFINED            cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
 794        DECODE_REJECT   (0x0ff000f0, 0x07f000f0),
 795
 796        /* SMLALD               cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
 797        /* SMLSLD               cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
 798        DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
 799                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 800
 801        /* SMUAD                cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
 802        /* SMUSD                cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
 803        DECODE_OR       (0x0ff0f090, 0x0700f010),
 804        /* SMMUL                cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
 805        DECODE_OR       (0x0ff0f0d0, 0x0750f010),
 806        /* USAD8                cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
 807        DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc,
 808                                                 REGS(NOPC, 0, NOPC, 0, NOPC)),
 809
 810        /* SMLAD                cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
 811        /* SMLSD                cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
 812        DECODE_OR       (0x0ff00090, 0x07000010),
 813        /* SMMLA                cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
 814        DECODE_OR       (0x0ff000d0, 0x07500010),
 815        /* USADA8               cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
 816        DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc,
 817                                                 REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
 818
 819        /* SMMLS                cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
 820        DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc,
 821                                                 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
 822
 823        /* SBFX                 cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
 824        /* UBFX                 cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
 825        DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc,
 826                                                 REGS(0, NOPC, 0, 0, NOPC)),
 827
 828        /* BFC                  cccc 0111 110x xxxx xxxx xxxx x001 1111 */
 829        DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc,
 830                                                 REGS(0, NOPC, 0, 0, 0)),
 831
 832        /* BFI                  cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
 833        DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc,
 834                                                 REGS(0, NOPC, 0, 0, NOPCX)),
 835
 836        DECODE_END
 837};
 838
 839static const union decode_item arm_cccc_01xx_table[] = {
 840        /* Load/store word and unsigned byte                            */
 841
 842        /* LDRB/STRB pc,[...]   cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
 843        DECODE_REJECT   (0x0c40f000, 0x0440f000),
 844
 845        /* STRT                 cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
 846        /* LDRT                 cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
 847        /* STRBT                cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
 848        /* LDRBT                cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
 849        DECODE_REJECT   (0x0d200000, 0x04200000),
 850
 851        /* STR (immediate)      cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
 852        /* STRB (immediate)     cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
 853        DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str,
 854                                                 REGS(NOPCWB, ANY, 0, 0, 0)),
 855
 856        /* LDR (immediate)      cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
 857        /* LDRB (immediate)     cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
 858        DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr,
 859                                                 REGS(NOPCWB, ANY, 0, 0, 0)),
 860
 861        /* STR (register)       cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
 862        /* STRB (register)      cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
 863        DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str,
 864                                                 REGS(NOPCWB, ANY, 0, 0, NOPC)),
 865
 866        /* LDR (register)       cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
 867        /* LDRB (register)      cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
 868        DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr,
 869                                                 REGS(NOPCWB, ANY, 0, 0, NOPC)),
 870
 871        DECODE_END
 872};
 873
 874static const union decode_item arm_cccc_100x_table[] = {
 875        /* Block data transfer instructions                             */
 876
 877        /* LDM                  cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
 878        /* STM                  cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
 879        DECODE_CUSTOM   (0x0e400000, 0x08000000, kprobe_decode_ldmstm),
 880
 881        /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
 882        /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
 883        /* LDM (exception ret)  cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
 884        DECODE_END
 885};
 886
 887const union decode_item kprobe_decode_arm_table[] = {
 888        /*
 889         * Unconditional instructions
 890         *                      1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
 891         */
 892        DECODE_TABLE    (0xf0000000, 0xf0000000, arm_1111_table),
 893
 894        /*
 895         * Miscellaneous instructions
 896         *                      cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
 897         */
 898        DECODE_TABLE    (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
 899
 900        /*
 901         * Halfword multiply and multiply-accumulate
 902         *                      cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
 903         */
 904        DECODE_TABLE    (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
 905
 906        /*
 907         * Multiply and multiply-accumulate
 908         *                      cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
 909         */
 910        DECODE_TABLE    (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
 911
 912        /*
 913         * Synchronization primitives
 914         *                      cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
 915         */
 916        DECODE_TABLE    (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
 917
 918        /*
 919         * Extra load/store instructions
 920         *                      cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
 921         */
 922        DECODE_TABLE    (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
 923
 924        /*
 925         * Data-processing (register)
 926         *                      cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
 927         * Data-processing (register-shifted register)
 928         *                      cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
 929         */
 930        DECODE_TABLE    (0x0e000000, 0x00000000, arm_cccc_000x_table),
 931
 932        /*
 933         * Data-processing (immediate)
 934         *                      cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
 935         */
 936        DECODE_TABLE    (0x0e000000, 0x02000000, arm_cccc_001x_table),
 937
 938        /*
 939         * Media instructions
 940         *                      cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
 941         */
 942        DECODE_TABLE    (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
 943        DECODE_TABLE    (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
 944
 945        /*
 946         * Load/store word and unsigned byte
 947         *                      cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
 948         */
 949        DECODE_TABLE    (0x0c000000, 0x04000000, arm_cccc_01xx_table),
 950
 951        /*
 952         * Block data transfer instructions
 953         *                      cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
 954         */
 955        DECODE_TABLE    (0x0e000000, 0x08000000, arm_cccc_100x_table),
 956
 957        /* B                    cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
 958        /* BL                   cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
 959        DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl),
 960
 961        /*
 962         * Supervisor Call, and coprocessor instructions
 963         */
 964
 965        /* MCRR                 cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
 966        /* MRRC                 cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
 967        /* LDC                  cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
 968        /* STC                  cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
 969        /* CDP                  cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
 970        /* MCR                  cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
 971        /* MRC                  cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
 972        /* SVC                  cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
 973        DECODE_REJECT   (0x0c000000, 0x0c000000),
 974
 975        DECODE_END
 976};
 977#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
 978EXPORT_SYMBOL_GPL(kprobe_decode_arm_table);
 979#endif
 980
 981static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs)
 982{
 983        regs->ARM_pc += 4;
 984        p->ainsn.insn_handler(p, regs);
 985}
 986
 987/* Return:
 988 *   INSN_REJECTED     If instruction is one not allowed to kprobe,
 989 *   INSN_GOOD         If instruction is supported and uses instruction slot,
 990 *   INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
 991 *
 992 * For instructions we don't want to kprobe (INSN_REJECTED return result):
 993 *   These are generally ones that modify the processor state making
 994 *   them "hard" to simulate such as switches processor modes or
 995 *   make accesses in alternate modes.  Any of these could be simulated
 996 *   if the work was put into it, but low return considering they
 997 *   should also be very rare.
 998 */
 999enum kprobe_insn __kprobes
1000arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1001{
1002        asi->insn_singlestep = arm_singlestep;
1003        asi->insn_check_cc = kprobe_condition_checks[insn>>28];
1004        return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false);
1005}
1006