linux-user/main.c

   1 /*
   2  *  qemu user main
   3  *
   4  *  Copyright (c) 2003-2008 Fabrice Bellard
   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 as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "qemu/help-texts.h"
  22 #include "qemu/units.h"
  23 #include "qemu/accel.h"
  24 #include "qemu-version.h"
  25 #include <sys/syscall.h>
  26 #include <sys/resource.h>
  27 #include <sys/shm.h>
  28 #include <linux/binfmts.h>
  29
  30 #include "qapi/error.h"
  31 #include "qemu.h"
  32 #include "user-internals.h"
  33 #include "qemu/path.h"
  34 #include "qemu/queue.h"
  35 #include "qemu/config-file.h"
  36 #include "qemu/cutils.h"
  37 #include "qemu/error-report.h"
  38 #include "qemu/help_option.h"
  39 #include "qemu/module.h"
  40 #include "qemu/plugin.h"
  41 #include "exec/exec-all.h"
  42 #include "exec/gdbstub.h"
  43 #include "tcg/tcg.h"
  44 #include "qemu/timer.h"
  45 #include "qemu/envlist.h"
  46 #include "qemu/guest-random.h"
  47 #include "elf.h"
  48 #include "trace/control.h"
  49 #include "target_elf.h"
  50 #include "cpu_loop-common.h"
  51 #include "crypto/init.h"
  52 #include "fd-trans.h"
  53 #include "signal-common.h"
  54 #include "loader.h"
  55 #include "user-mmap.h"
  56 #include "accel/tcg/perf.h"
  57
  58 #ifdef CONFIG_SEMIHOSTING
  59 #include "semihosting/semihost.h"
  60 #endif
  61
  62 #ifndef AT_FLAGS_PRESERVE_ARGV0
  63 #define AT_FLAGS_PRESERVE_ARGV0_BIT 0
  64 #define AT_FLAGS_PRESERVE_ARGV0 (1 << AT_FLAGS_PRESERVE_ARGV0_BIT)
  65 #endif
  66
  67 char *exec_path;
  68
  69 int singlestep;
  70 static const char *argv0;
  71 static const char *gdbstub;
  72 static envlist_t *envlist;
  73 static const char *cpu_model;
  74 static const char *cpu_type;
  75 static const char *seed_optarg;
  76 unsigned long mmap_min_addr;
  77 uintptr_t guest_base;
  78 bool have_guest_base;
  79
  80 /*
  81  * Used to implement backwards-compatibility for the `-strace`, and
  82  * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by
  83  * -strace, or vice versa.
  84  */
  85 static bool enable_strace;
  86
  87 /*
  88  * The last log mask given by the user in an environment variable or argument.
  89  * Used to support command line arguments overriding environment variables.
  90  */
  91 static int last_log_mask;
  92 static const char *last_log_filename;
  93
  94 /*
  95  * When running 32-on-64 we should make sure we can fit all of the possible
  96  * guest address space into a contiguous chunk of virtual host memory.
  97  *
  98  * This way we will never overlap with our own libraries or binaries or stack
  99  * or anything else that QEMU maps.
 100  *
 101  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
 102  * of the address for the kernel.  Some cpus rely on this and user space
 103  * uses the high bit(s) for pointer tagging and the like.  For them, we
 104  * must preserve the expected address space.
 105  */
 106 #ifndef MAX_RESERVED_VA
 107 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
 108 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
 109       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
 110 /* There are a number of places where we assign reserved_va to a variable
 111    of type abi_ulong and expect it to fit.  Avoid the last page.  */
 112 #   define MAX_RESERVED_VA(CPU)  (0xfffffffful & TARGET_PAGE_MASK)
 113 #  else
 114 #   define MAX_RESERVED_VA(CPU)  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
 115 #  endif
 116 # else
 117 #  define MAX_RESERVED_VA(CPU)  0
 118 # endif
 119 #endif
 120
 121 unsigned long reserved_va;
 122
 123 static void usage(int exitcode);
 124
 125 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
 126 const char *qemu_uname_release;
 127
 128 #if !defined(TARGET_DEFAULT_STACK_SIZE)
 129 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
 130    we allocate a bigger stack. Need a better solution, for example
 131    by remapping the process stack directly at the right place */
 132 #define TARGET_DEFAULT_STACK_SIZE       8 * 1024 * 1024UL
 133 #endif
 134
 135 unsigned long guest_stack_size = TARGET_DEFAULT_STACK_SIZE;
 136
 137 /***********************************************************/
 138 /* Helper routines for implementing atomic operations.  */
 139
 140 /* Make sure everything is in a consistent state for calling fork().  */
 141 void fork_start(void)
 142 {
 143     start_exclusive();
 144     mmap_fork_start();
 145     cpu_list_lock();
 146     qemu_plugin_user_prefork_lock();
 147 }
 148
 149 void fork_end(int child)
 150 {
 151     qemu_plugin_user_postfork(child);
 152     mmap_fork_end(child);
 153     if (child) {
 154         CPUState *cpu, *next_cpu;
 155         /* Child processes created by fork() only have a single thread.
 156            Discard information about the parent threads.  */
 157         CPU_FOREACH_SAFE(cpu, next_cpu) {
 158             if (cpu != thread_cpu) {
 159                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 160             }
 161         }
 162         qemu_init_cpu_list();
 163         gdbserver_fork(thread_cpu);
 164         /* qemu_init_cpu_list() takes care of reinitializing the
 165          * exclusive state, so we don't need to end_exclusive() here.
 166          */
 167     } else {
 168         cpu_list_unlock();
 169         end_exclusive();
 170     }
 171 }
 172
 173 __thread CPUState *thread_cpu;
 174
 175 bool qemu_cpu_is_self(CPUState *cpu)
 176 {
 177     return thread_cpu == cpu;
 178 }
 179
 180 void qemu_cpu_kick(CPUState *cpu)
 181 {
 182     cpu_exit(cpu);
 183 }
 184
 185 void task_settid(TaskState *ts)
 186 {
 187     if (ts->ts_tid == 0) {
 188         ts->ts_tid = (pid_t)syscall(SYS_gettid);
 189     }
 190 }
 191
 192 void stop_all_tasks(void)
 193 {
 194     /*
 195      * We trust that when using NPTL, start_exclusive()
 196      * handles thread stopping correctly.
 197      */
 198     start_exclusive();
 199 }
 200
 201 /* Assumes contents are already zeroed.  */
 202 void init_task_state(TaskState *ts)
 203 {
 204     long ticks_per_sec;
 205     struct timespec bt;
 206
 207     ts->used = 1;
 208     ts->sigaltstack_used = (struct target_sigaltstack) {
 209         .ss_sp = 0,
 210         .ss_size = 0,
 211         .ss_flags = TARGET_SS_DISABLE,
 212     };
 213
 214     /* Capture task start time relative to system boot */
 215
 216     ticks_per_sec = sysconf(_SC_CLK_TCK);
 217
 218     if ((ticks_per_sec > 0) && !clock_gettime(CLOCK_BOOTTIME, &bt)) {
 219         /* start_boottime is expressed in clock ticks */
 220         ts->start_boottime = bt.tv_sec * (uint64_t) ticks_per_sec;
 221         ts->start_boottime += bt.tv_nsec * (uint64_t) ticks_per_sec /
 222                               NANOSECONDS_PER_SECOND;
 223     }
 224 }
 225
 226 CPUArchState *cpu_copy(CPUArchState *env)
 227 {
 228     CPUState *cpu = env_cpu(env);
 229     CPUState *new_cpu = cpu_create(cpu_type);
 230     CPUArchState *new_env = new_cpu->env_ptr;
 231     CPUBreakpoint *bp;
 232
 233     /* Reset non arch specific state */
 234     cpu_reset(new_cpu);
 235
 236     new_cpu->tcg_cflags = cpu->tcg_cflags;
 237     memcpy(new_env, env, sizeof(CPUArchState));
 238
 239     /* Clone all break/watchpoints.
 240        Note: Once we support ptrace with hw-debug register access, make sure
 241        BP_CPU break/watchpoints are handled correctly on clone. */
 242     QTAILQ_INIT(&new_cpu->breakpoints);
 243     QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
 244         cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
 245     }
 246
 247     return new_env;
 248 }
 249
 250 static void handle_arg_help(const char *arg)
 251 {
 252     usage(EXIT_SUCCESS);
 253 }
 254
 255 static void handle_arg_log(const char *arg)
 256 {
 257     last_log_mask = qemu_str_to_log_mask(arg);
 258     if (!last_log_mask) {
 259         qemu_print_log_usage(stdout);
 260         exit(EXIT_FAILURE);
 261     }
 262 }
 263
 264 static void handle_arg_dfilter(const char *arg)
 265 {
 266     qemu_set_dfilter_ranges(arg, &error_fatal);
 267 }
 268
 269 static void handle_arg_log_filename(const char *arg)
 270 {
 271     last_log_filename = arg;
 272 }
 273
 274 static void handle_arg_set_env(const char *arg)
 275 {
 276     char *r, *p, *token;
 277     r = p = strdup(arg);
 278     while ((token = strsep(&p, ",")) != NULL) {
 279         if (envlist_setenv(envlist, token) != 0) {
 280             usage(EXIT_FAILURE);
 281         }
 282     }
 283     free(r);
 284 }
 285
 286 static void handle_arg_unset_env(const char *arg)
 287 {
 288     char *r, *p, *token;
 289     r = p = strdup(arg);
 290     while ((token = strsep(&p, ",")) != NULL) {
 291         if (envlist_unsetenv(envlist, token) != 0) {
 292             usage(EXIT_FAILURE);
 293         }
 294     }
 295     free(r);
 296 }
 297
 298 static void handle_arg_argv0(const char *arg)
 299 {
 300     argv0 = strdup(arg);
 301 }
 302
 303 static void handle_arg_stack_size(const char *arg)
 304 {
 305     char *p;
 306     guest_stack_size = strtoul(arg, &p, 0);
 307     if (guest_stack_size == 0) {
 308         usage(EXIT_FAILURE);
 309     }
 310
 311     if (*p == 'M') {
 312         guest_stack_size *= MiB;
 313     } else if (*p == 'k' || *p == 'K') {
 314         guest_stack_size *= KiB;
 315     }
 316 }
 317
 318 static void handle_arg_ld_prefix(const char *arg)
 319 {
 320     interp_prefix = strdup(arg);
 321 }
 322
 323 static void handle_arg_pagesize(const char *arg)
 324 {
 325     qemu_host_page_size = atoi(arg);
 326     if (qemu_host_page_size == 0 ||
 327         (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 328         fprintf(stderr, "page size must be a power of two\n");
 329         exit(EXIT_FAILURE);
 330     }
 331 }
 332
 333 static void handle_arg_seed(const char *arg)
 334 {
 335     seed_optarg = arg;
 336 }
 337
 338 static void handle_arg_gdb(const char *arg)
 339 {
 340     gdbstub = g_strdup(arg);
 341 }
 342
 343 static void handle_arg_uname(const char *arg)
 344 {
 345     qemu_uname_release = strdup(arg);
 346 }
 347
 348 static void handle_arg_cpu(const char *arg)
 349 {
 350     cpu_model = strdup(arg);
 351     if (cpu_model == NULL || is_help_option(cpu_model)) {
 352         /* XXX: implement xxx_cpu_list for targets that still miss it */
 353 #if defined(cpu_list)
 354         cpu_list();
 355 #endif
 356         exit(EXIT_FAILURE);
 357     }
 358 }
 359
 360 static void handle_arg_guest_base(const char *arg)
 361 {
 362     guest_base = strtol(arg, NULL, 0);
 363     have_guest_base = true;
 364 }
 365
 366 static void handle_arg_reserved_va(const char *arg)
 367 {
 368     char *p;
 369     int shift = 0;
 370     reserved_va = strtoul(arg, &p, 0);
 371     switch (*p) {
 372     case 'k':
 373     case 'K':
 374         shift = 10;
 375         break;
 376     case 'M':
 377         shift = 20;
 378         break;
 379     case 'G':
 380         shift = 30;
 381         break;
 382     }
 383     if (shift) {
 384         unsigned long unshifted = reserved_va;
 385         p++;
 386         reserved_va <<= shift;
 387         if (reserved_va >> shift != unshifted) {
 388             fprintf(stderr, "Reserved virtual address too big\n");
 389             exit(EXIT_FAILURE);
 390         }
 391     }
 392     if (*p) {
 393         fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
 394         exit(EXIT_FAILURE);
 395     }
 396 }
 397
 398 static void handle_arg_singlestep(const char *arg)
 399 {
 400     singlestep = 1;
 401 }
 402
 403 static void handle_arg_strace(const char *arg)
 404 {
 405     enable_strace = true;
 406 }
 407
 408 static void handle_arg_version(const char *arg)
 409 {
 410     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 411            "\n" QEMU_COPYRIGHT "\n");
 412     exit(EXIT_SUCCESS);
 413 }
 414
 415 static void handle_arg_trace(const char *arg)
 416 {
 417     trace_opt_parse(arg);
 418 }
 419
 420 #if defined(TARGET_XTENSA)
 421 static void handle_arg_abi_call0(const char *arg)
 422 {
 423     xtensa_set_abi_call0();
 424 }
 425 #endif
 426
 427 static void handle_arg_perfmap(const char *arg)
 428 {
 429     perf_enable_perfmap();
 430 }
 431
 432 static void handle_arg_jitdump(const char *arg)
 433 {
 434     perf_enable_jitdump();
 435 }
 436
 437 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
 438
 439 #ifdef CONFIG_PLUGIN
 440 static void handle_arg_plugin(const char *arg)
 441 {
 442     qemu_plugin_opt_parse(arg, &plugins);
 443 }
 444 #endif
 445
 446 struct qemu_argument {
 447     const char *argv;
 448     const char *env;
 449     bool has_arg;
 450     void (*handle_opt)(const char *arg);
 451     const char *example;
 452     const char *help;
 453 };
 454
 455 static const struct qemu_argument arg_table[] = {
 456     {"h",          "",                 false, handle_arg_help,
 457      "",           "print this help"},
 458     {"help",       "",                 false, handle_arg_help,
 459      "",           ""},
 460     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 461      "port",       "wait gdb connection to 'port'"},
 462     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 463      "path",       "set the elf interpreter prefix to 'path'"},
 464     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 465      "size",       "set the stack size to 'size' bytes"},
 466     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 467      "model",      "select CPU (-cpu help for list)"},
 468     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 469      "var=value",  "sets targets environment variable (see below)"},
 470     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 471      "var",        "unsets targets environment variable (see below)"},
 472     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 473      "argv0",      "forces target process argv[0] to be 'argv0'"},
 474     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 475      "uname",      "set qemu uname release string to 'uname'"},
 476     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 477      "address",    "set guest_base address to 'address'"},
 478     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 479      "size",       "reserve 'size' bytes for guest virtual address space"},
 480     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 481      "item[,...]", "enable logging of specified items "
 482      "(use '-d help' for a list of items)"},
 483     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 484      "range[,...]","filter logging based on address range"},
 485     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 486      "logfile",     "write logs to 'logfile' (default stderr)"},
 487     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 488      "pagesize",   "set the host page size to 'pagesize'"},
 489     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 490      "",           "run in singlestep mode"},
 491     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 492      "",           "log system calls"},
 493     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_seed,
 494      "",           "Seed for pseudo-random number generator"},
 495     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 496      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 497 #ifdef CONFIG_PLUGIN
 498     {"plugin",     "QEMU_PLUGIN",      true,  handle_arg_plugin,
 499      "",           "[file=]<file>[,<argname>=<argvalue>]"},
 500 #endif
 501     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 502      "",           "display version information and exit"},
 503 #if defined(TARGET_XTENSA)
 504     {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
 505      "",           "assume CALL0 Xtensa ABI"},
 506 #endif
 507     {"perfmap",    "QEMU_PERFMAP",     false, handle_arg_perfmap,
 508      "",           "Generate a /tmp/perf-${pid}.map file for perf"},
 509     {"jitdump",    "QEMU_JITDUMP",     false, handle_arg_jitdump,
 510      "",           "Generate a jit-${pid}.dump file for perf"},
 511     {NULL, NULL, false, NULL, NULL, NULL}
 512 };
 513
 514 static void usage(int exitcode)
 515 {
 516     const struct qemu_argument *arginfo;
 517     int maxarglen;
 518     int maxenvlen;
 519
 520     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 521            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 522            "\n"
 523            "Options and associated environment variables:\n"
 524            "\n");
 525
 526     /* Calculate column widths. We must always have at least enough space
 527      * for the column header.
 528      */
 529     maxarglen = strlen("Argument");
 530     maxenvlen = strlen("Env-variable");
 531
 532     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 533         int arglen = strlen(arginfo->argv);
 534         if (arginfo->has_arg) {
 535             arglen += strlen(arginfo->example) + 1;
 536         }
 537         if (strlen(arginfo->env) > maxenvlen) {
 538             maxenvlen = strlen(arginfo->env);
 539         }
 540         if (arglen > maxarglen) {
 541             maxarglen = arglen;
 542         }
 543     }
 544
 545     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 546             maxenvlen, "Env-variable");
 547
 548     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 549         if (arginfo->has_arg) {
 550             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 551                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 552                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 553         } else {
 554             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 555                     maxenvlen, arginfo->env,
 556                     arginfo->help);
 557         }
 558     }
 559
 560     printf("\n"
 561            "Defaults:\n"
 562            "QEMU_LD_PREFIX  = %s\n"
 563            "QEMU_STACK_SIZE = %ld byte\n",
 564            interp_prefix,
 565            guest_stack_size);
 566
 567     printf("\n"
 568            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 569            "QEMU_UNSET_ENV environment variables to set and unset\n"
 570            "environment variables for the target process.\n"
 571            "It is possible to provide several variables by separating them\n"
 572            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 573            "provide the -E and -U options multiple times.\n"
 574            "The following lines are equivalent:\n"
 575            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 576            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 577            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 578            "Note that if you provide several changes to a single variable\n"
 579            "the last change will stay in effect.\n"
 580            "\n"
 581            QEMU_HELP_BOTTOM "\n");
 582
 583     exit(exitcode);
 584 }
 585
 586 static int parse_args(int argc, char **argv)
 587 {
 588     const char *r;
 589     int optind;
 590     const struct qemu_argument *arginfo;
 591
 592     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 593         if (arginfo->env == NULL) {
 594             continue;
 595         }
 596
 597         r = getenv(arginfo->env);
 598         if (r != NULL) {
 599             arginfo->handle_opt(r);
 600         }
 601     }
 602
 603     optind = 1;
 604     for (;;) {
 605         if (optind >= argc) {
 606             break;
 607         }
 608         r = argv[optind];
 609         if (r[0] != '-') {
 610             break;
 611         }
 612         optind++;
 613         r++;
 614         if (!strcmp(r, "-")) {
 615             break;
 616         }
 617         /* Treat --foo the same as -foo.  */
 618         if (r[0] == '-') {
 619             r++;
 620         }
 621
 622         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 623             if (!strcmp(r, arginfo->argv)) {
 624                 if (arginfo->has_arg) {
 625                     if (optind >= argc) {
 626                         (void) fprintf(stderr,
 627                             "qemu: missing argument for option '%s'\n", r);
 628                         exit(EXIT_FAILURE);
 629                     }
 630                     arginfo->handle_opt(argv[optind]);
 631                     optind++;
 632                 } else {
 633                     arginfo->handle_opt(NULL);
 634                 }
 635                 break;
 636             }
 637         }
 638
 639         /* no option matched the current argv */
 640         if (arginfo->handle_opt == NULL) {
 641             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 642             exit(EXIT_FAILURE);
 643         }
 644     }
 645
 646     if (optind >= argc) {
 647         (void) fprintf(stderr, "qemu: no user program specified\n");
 648         exit(EXIT_FAILURE);
 649     }
 650
 651     exec_path = argv[optind];
 652
 653     return optind;
 654 }
 655
 656 int main(int argc, char **argv, char **envp)
 657 {
 658     struct target_pt_regs regs1, *regs = &regs1;
 659     struct image_info info1, *info = &info1;
 660     struct linux_binprm bprm;
 661     TaskState *ts;
 662     CPUArchState *env;
 663     CPUState *cpu;
 664     int optind;
 665     char **target_environ, **wrk;
 666     char **target_argv;
 667     int target_argc;
 668     int i;
 669     int ret;
 670     int execfd;
 671     unsigned long max_reserved_va;
 672     bool preserve_argv0;
 673
 674     error_init(argv[0]);
 675     module_call_init(MODULE_INIT_TRACE);
 676     qemu_init_cpu_list();
 677     module_call_init(MODULE_INIT_QOM);
 678
 679     envlist = envlist_create();
 680
 681     /* add current environment into the list */
 682     for (wrk = environ; *wrk != NULL; wrk++) {
 683         (void) envlist_setenv(envlist, *wrk);
 684     }
 685
 686     /* Read the stack limit from the kernel.  If it's "unlimited",
 687        then we can do little else besides use the default.  */
 688     {
 689         struct rlimit lim;
 690         if (getrlimit(RLIMIT_STACK, &lim) == 0
 691             && lim.rlim_cur != RLIM_INFINITY
 692             && lim.rlim_cur == (target_long)lim.rlim_cur
 693             && lim.rlim_cur > guest_stack_size) {
 694             guest_stack_size = lim.rlim_cur;
 695         }
 696     }
 697
 698     cpu_model = NULL;
 699
 700     qemu_add_opts(&qemu_trace_opts);
 701     qemu_plugin_add_opts();
 702
 703     optind = parse_args(argc, argv);
 704
 705     qemu_set_log_filename_flags(last_log_filename,
 706                                 last_log_mask | (enable_strace * LOG_STRACE),
 707                                 &error_fatal);
 708
 709     if (!trace_init_backends()) {
 710         exit(1);
 711     }
 712     trace_init_file();
 713     qemu_plugin_load_list(&plugins, &error_fatal);
 714
 715     /* Zero out regs */
 716     memset(regs, 0, sizeof(struct target_pt_regs));
 717
 718     /* Zero out image_info */
 719     memset(info, 0, sizeof(struct image_info));
 720
 721     memset(&bprm, 0, sizeof (bprm));
 722
 723     /* Scan interp_prefix dir for replacement files. */
 724     init_paths(interp_prefix);
 725
 726     init_qemu_uname_release();
 727
 728     /*
 729      * Manage binfmt-misc open-binary flag
 730      */
 731     execfd = qemu_getauxval(AT_EXECFD);
 732     if (execfd == 0) {
 733         execfd = open(exec_path, O_RDONLY);
 734         if (execfd < 0) {
 735             printf("Error while loading %s: %s\n", exec_path, strerror(errno));
 736             _exit(EXIT_FAILURE);
 737         }
 738     }
 739
 740     /*
 741      * get binfmt_misc flags
 742      */
 743     preserve_argv0 = !!(qemu_getauxval(AT_FLAGS) & AT_FLAGS_PRESERVE_ARGV0);
 744
 745     /*
 746      * Manage binfmt-misc preserve-arg[0] flag
 747      *    argv[optind]     full path to the binary
 748      *    argv[optind + 1] original argv[0]
 749      */
 750     if (optind + 1 < argc && preserve_argv0) {
 751         optind++;
 752     }
 753
 754     if (cpu_model == NULL) {
 755         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 756     }
 757     cpu_type = parse_cpu_option(cpu_model);
 758
 759     /* init tcg before creating CPUs and to get qemu_host_page_size */
 760     {
 761         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 762
 763         accel_init_interfaces(ac);
 764         ac->init_machine(NULL);
 765     }
 766     cpu = cpu_create(cpu_type);
 767     env = cpu->env_ptr;
 768     cpu_reset(cpu);
 769     thread_cpu = cpu;
 770
 771     /*
 772      * Reserving too much vm space via mmap can run into problems
 773      * with rlimits, oom due to page table creation, etc.  We will
 774      * still try it, if directed by the command-line option, but
 775      * not by default.
 776      */
 777     max_reserved_va = MAX_RESERVED_VA(cpu);
 778     if (reserved_va != 0) {
 779         if (max_reserved_va && reserved_va > max_reserved_va) {
 780             fprintf(stderr, "Reserved virtual address too big\n");
 781             exit(EXIT_FAILURE);
 782         }
 783     } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
 784         /*
 785          * reserved_va must be aligned with the host page size
 786          * as it is used with mmap()
 787          */
 788         reserved_va = max_reserved_va & qemu_host_page_mask;
 789     }
 790
 791     {
 792         Error *err = NULL;
 793         if (seed_optarg != NULL) {
 794             qemu_guest_random_seed_main(seed_optarg, &err);
 795         } else {
 796             qcrypto_init(&err);
 797         }
 798         if (err) {
 799             error_reportf_err(err, "cannot initialize crypto: ");
 800             exit(1);
 801         }
 802     }
 803
 804     target_environ = envlist_to_environ(envlist, NULL);
 805     envlist_free(envlist);
 806
 807     /*
 808      * Read in mmap_min_addr kernel parameter.  This value is used
 809      * When loading the ELF image to determine whether guest_base
 810      * is needed.  It is also used in mmap_find_vma.
 811      */
 812     {
 813         FILE *fp;
 814
 815         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 816             unsigned long tmp;
 817             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
 818                 mmap_min_addr = tmp;
 819                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
 820                               mmap_min_addr);
 821             }
 822             fclose(fp);
 823         }
 824     }
 825
 826     /*
 827      * We prefer to not make NULL pointers accessible to QEMU.
 828      * If we're in a chroot with no /proc, fall back to 1 page.
 829      */
 830     if (mmap_min_addr == 0) {
 831         mmap_min_addr = qemu_host_page_size;
 832         qemu_log_mask(CPU_LOG_PAGE,
 833                       "host mmap_min_addr=0x%lx (fallback)\n",
 834                       mmap_min_addr);
 835     }
 836
 837     /*
 838      * Prepare copy of argv vector for target.
 839      */
 840     target_argc = argc - optind;
 841     target_argv = calloc(target_argc + 1, sizeof (char *));
 842     if (target_argv == NULL) {
 843         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 844         exit(EXIT_FAILURE);
 845     }
 846
 847     /*
 848      * If argv0 is specified (using '-0' switch) we replace
 849      * argv[0] pointer with the given one.
 850      */
 851     i = 0;
 852     if (argv0 != NULL) {
 853         target_argv[i++] = strdup(argv0);
 854     }
 855     for (; i < target_argc; i++) {
 856         target_argv[i] = strdup(argv[optind + i]);
 857     }
 858     target_argv[target_argc] = NULL;
 859
 860     ts = g_new0(TaskState, 1);
 861     init_task_state(ts);
 862     /* build Task State */
 863     ts->info = info;
 864     ts->bprm = &bprm;
 865     cpu->opaque = ts;
 866     task_settid(ts);
 867
 868     fd_trans_init();
 869
 870     ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
 871         info, &bprm);
 872     if (ret != 0) {
 873         printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
 874         _exit(EXIT_FAILURE);
 875     }
 876
 877     for (wrk = target_environ; *wrk; wrk++) {
 878         g_free(*wrk);
 879     }
 880
 881     g_free(target_environ);
 882
 883     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 884         FILE *f = qemu_log_trylock();
 885         if (f) {
 886             fprintf(f, "guest_base  %p\n", (void *)guest_base);
 887             fprintf(f, "page layout changed following binary load\n");
 888             page_dump(f);
 889
 890             fprintf(f, "start_brk   0x" TARGET_ABI_FMT_lx "\n",
 891                     info->start_brk);
 892             fprintf(f, "end_code    0x" TARGET_ABI_FMT_lx "\n",
 893                     info->end_code);
 894             fprintf(f, "start_code  0x" TARGET_ABI_FMT_lx "\n",
 895                     info->start_code);
 896             fprintf(f, "start_data  0x" TARGET_ABI_FMT_lx "\n",
 897                     info->start_data);
 898             fprintf(f, "end_data    0x" TARGET_ABI_FMT_lx "\n",
 899                     info->end_data);
 900             fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n",
 901                     info->start_stack);
 902             fprintf(f, "brk         0x" TARGET_ABI_FMT_lx "\n",
 903                     info->brk);
 904             fprintf(f, "entry       0x" TARGET_ABI_FMT_lx "\n",
 905                     info->entry);
 906             fprintf(f, "argv_start  0x" TARGET_ABI_FMT_lx "\n",
 907                     info->argv);
 908             fprintf(f, "env_start   0x" TARGET_ABI_FMT_lx "\n",
 909                     info->envp);
 910             fprintf(f, "auxv_start  0x" TARGET_ABI_FMT_lx "\n",
 911                     info->saved_auxv);
 912             qemu_log_unlock(f);
 913         }
 914     }
 915
 916     target_set_brk(info->brk);
 917     syscall_init();
 918     signal_init();
 919
 920     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 921        generating the prologue until now so that the prologue can take
 922        the real value of GUEST_BASE into account.  */
 923     tcg_prologue_init(tcg_ctx);
 924
 925     target_cpu_copy_regs(env, regs);
 926
 927     if (gdbstub) {
 928         if (gdbserver_start(gdbstub) < 0) {
 929             fprintf(stderr, "qemu: could not open gdbserver on %s\n",
 930                     gdbstub);
 931             exit(EXIT_FAILURE);
 932         }
 933         gdb_handlesig(cpu, 0);
 934     }
 935
 936 #ifdef CONFIG_SEMIHOSTING
 937     qemu_semihosting_guestfd_init();
 938 #endif
 939
 940     cpu_loop(env);
 941     /* never exits */
 942     return 0;
 943 }