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-common.h"
  22 #include "qemu/units.h"
  23 #include "sysemu/tcg.h"
  24 #include "qemu-version.h"
  25 #include <sys/syscall.h>
  26 #include <sys/resource.h>
  27 #include <sys/shm.h>
  28
  29 #include "qapi/error.h"
  30 #include "qemu.h"
  31 #include "qemu/path.h"
  32 #include "qemu/queue.h"
  33 #include "qemu/config-file.h"
  34 #include "qemu/cutils.h"
  35 #include "qemu/error-report.h"
  36 #include "qemu/help_option.h"
  37 #include "qemu/module.h"
  38 #include "qemu/plugin.h"
  39 #include "cpu.h"
  40 #include "exec/exec-all.h"
  41 #include "tcg/tcg.h"
  42 #include "qemu/timer.h"
  43 #include "qemu/envlist.h"
  44 #include "qemu/guest-random.h"
  45 #include "elf.h"
  46 #include "trace/control.h"
  47 #include "target_elf.h"
  48 #include "cpu_loop-common.h"
  49 #include "crypto/init.h"
  50
  51 char *exec_path;
  52
  53 int singlestep;
  54 static const char *argv0;
  55 static const char *gdbstub;
  56 static envlist_t *envlist;
  57 static const char *cpu_model;
  58 static const char *cpu_type;
  59 static const char *seed_optarg;
  60 unsigned long mmap_min_addr;
  61 unsigned long guest_base;
  62 bool have_guest_base;
  63
  64 /*
  65  * Used to implement backwards-compatibility for the `-strace`, and
  66  * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by
  67  * -strace, or vice versa.
  68  */
  69 static bool enable_strace;
  70
  71 /*
  72  * The last log mask given by the user in an environment variable or argument.
  73  * Used to support command line arguments overriding environment variables.
  74  */
  75 static int last_log_mask;
  76
  77 /*
  78  * When running 32-on-64 we should make sure we can fit all of the possible
  79  * guest address space into a contiguous chunk of virtual host memory.
  80  *
  81  * This way we will never overlap with our own libraries or binaries or stack
  82  * or anything else that QEMU maps.
  83  *
  84  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  85  * of the address for the kernel.  Some cpus rely on this and user space
  86  * uses the high bit(s) for pointer tagging and the like.  For them, we
  87  * must preserve the expected address space.
  88  */
  89 #ifndef MAX_RESERVED_VA
  90 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
  91 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
  92       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
  93 /* There are a number of places where we assign reserved_va to a variable
  94    of type abi_ulong and expect it to fit.  Avoid the last page.  */
  95 #   define MAX_RESERVED_VA(CPU)  (0xfffffffful & TARGET_PAGE_MASK)
  96 #  else
  97 #   define MAX_RESERVED_VA(CPU)  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
  98 #  endif
  99 # else
 100 #  define MAX_RESERVED_VA(CPU)  0
 101 # endif
 102 #endif
 103
 104 unsigned long reserved_va;
 105
 106 static void usage(int exitcode);
 107
 108 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
 109 const char *qemu_uname_release;
 110
 111 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
 112    we allocate a bigger stack. Need a better solution, for example
 113    by remapping the process stack directly at the right place */
 114 unsigned long guest_stack_size = 8 * 1024 * 1024UL;
 115
 116 #if defined(TARGET_I386)
 117 int cpu_get_pic_interrupt(CPUX86State *env)
 118 {
 119     return -1;
 120 }
 121 #endif
 122
 123 /***********************************************************/
 124 /* Helper routines for implementing atomic operations.  */
 125
 126 /* Make sure everything is in a consistent state for calling fork().  */
 127 void fork_start(void)
 128 {
 129     start_exclusive();
 130     mmap_fork_start();
 131     cpu_list_lock();
 132 }
 133
 134 void fork_end(int child)
 135 {
 136     mmap_fork_end(child);
 137     if (child) {
 138         CPUState *cpu, *next_cpu;
 139         /* Child processes created by fork() only have a single thread.
 140            Discard information about the parent threads.  */
 141         CPU_FOREACH_SAFE(cpu, next_cpu) {
 142             if (cpu != thread_cpu) {
 143                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 144             }
 145         }
 146         qemu_init_cpu_list();
 147         gdbserver_fork(thread_cpu);
 148         /* qemu_init_cpu_list() takes care of reinitializing the
 149          * exclusive state, so we don't need to end_exclusive() here.
 150          */
 151     } else {
 152         cpu_list_unlock();
 153         end_exclusive();
 154     }
 155 }
 156
 157 __thread CPUState *thread_cpu;
 158
 159 bool qemu_cpu_is_self(CPUState *cpu)
 160 {
 161     return thread_cpu == cpu;
 162 }
 163
 164 void qemu_cpu_kick(CPUState *cpu)
 165 {
 166     cpu_exit(cpu);
 167 }
 168
 169 void task_settid(TaskState *ts)
 170 {
 171     if (ts->ts_tid == 0) {
 172         ts->ts_tid = (pid_t)syscall(SYS_gettid);
 173     }
 174 }
 175
 176 void stop_all_tasks(void)
 177 {
 178     /*
 179      * We trust that when using NPTL, start_exclusive()
 180      * handles thread stopping correctly.
 181      */
 182     start_exclusive();
 183 }
 184
 185 /* Assumes contents are already zeroed.  */
 186 void init_task_state(TaskState *ts)
 187 {
 188     ts->used = 1;
 189     ts->sigaltstack_used = (struct target_sigaltstack) {
 190         .ss_sp = 0,
 191         .ss_size = 0,
 192         .ss_flags = TARGET_SS_DISABLE,
 193     };
 194 }
 195
 196 CPUArchState *cpu_copy(CPUArchState *env)
 197 {
 198     CPUState *cpu = env_cpu(env);
 199     CPUState *new_cpu = cpu_create(cpu_type);
 200     CPUArchState *new_env = new_cpu->env_ptr;
 201     CPUBreakpoint *bp;
 202     CPUWatchpoint *wp;
 203
 204     /* Reset non arch specific state */
 205     cpu_reset(new_cpu);
 206
 207     memcpy(new_env, env, sizeof(CPUArchState));
 208
 209     /* Clone all break/watchpoints.
 210        Note: Once we support ptrace with hw-debug register access, make sure
 211        BP_CPU break/watchpoints are handled correctly on clone. */
 212     QTAILQ_INIT(&new_cpu->breakpoints);
 213     QTAILQ_INIT(&new_cpu->watchpoints);
 214     QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
 215         cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
 216     }
 217     QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
 218         cpu_watchpoint_insert(new_cpu, wp->vaddr, wp->len, wp->flags, NULL);
 219     }
 220
 221     return new_env;
 222 }
 223
 224 static void handle_arg_help(const char *arg)
 225 {
 226     usage(EXIT_SUCCESS);
 227 }
 228
 229 static void handle_arg_log(const char *arg)
 230 {
 231     last_log_mask = qemu_str_to_log_mask(arg);
 232     if (!last_log_mask) {
 233         qemu_print_log_usage(stdout);
 234         exit(EXIT_FAILURE);
 235     }
 236 }
 237
 238 static void handle_arg_dfilter(const char *arg)
 239 {
 240     qemu_set_dfilter_ranges(arg, &error_fatal);
 241 }
 242
 243 static void handle_arg_log_filename(const char *arg)
 244 {
 245     qemu_set_log_filename(arg, &error_fatal);
 246 }
 247
 248 static void handle_arg_set_env(const char *arg)
 249 {
 250     char *r, *p, *token;
 251     r = p = strdup(arg);
 252     while ((token = strsep(&p, ",")) != NULL) {
 253         if (envlist_setenv(envlist, token) != 0) {
 254             usage(EXIT_FAILURE);
 255         }
 256     }
 257     free(r);
 258 }
 259
 260 static void handle_arg_unset_env(const char *arg)
 261 {
 262     char *r, *p, *token;
 263     r = p = strdup(arg);
 264     while ((token = strsep(&p, ",")) != NULL) {
 265         if (envlist_unsetenv(envlist, token) != 0) {
 266             usage(EXIT_FAILURE);
 267         }
 268     }
 269     free(r);
 270 }
 271
 272 static void handle_arg_argv0(const char *arg)
 273 {
 274     argv0 = strdup(arg);
 275 }
 276
 277 static void handle_arg_stack_size(const char *arg)
 278 {
 279     char *p;
 280     guest_stack_size = strtoul(arg, &p, 0);
 281     if (guest_stack_size == 0) {
 282         usage(EXIT_FAILURE);
 283     }
 284
 285     if (*p == 'M') {
 286         guest_stack_size *= MiB;
 287     } else if (*p == 'k' || *p == 'K') {
 288         guest_stack_size *= KiB;
 289     }
 290 }
 291
 292 static void handle_arg_ld_prefix(const char *arg)
 293 {
 294     interp_prefix = strdup(arg);
 295 }
 296
 297 static void handle_arg_pagesize(const char *arg)
 298 {
 299     qemu_host_page_size = atoi(arg);
 300     if (qemu_host_page_size == 0 ||
 301         (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 302         fprintf(stderr, "page size must be a power of two\n");
 303         exit(EXIT_FAILURE);
 304     }
 305 }
 306
 307 static void handle_arg_seed(const char *arg)
 308 {
 309     seed_optarg = arg;
 310 }
 311
 312 static void handle_arg_gdb(const char *arg)
 313 {
 314     gdbstub = g_strdup(arg);
 315 }
 316
 317 static void handle_arg_uname(const char *arg)
 318 {
 319     qemu_uname_release = strdup(arg);
 320 }
 321
 322 static void handle_arg_cpu(const char *arg)
 323 {
 324     cpu_model = strdup(arg);
 325     if (cpu_model == NULL || is_help_option(cpu_model)) {
 326         /* XXX: implement xxx_cpu_list for targets that still miss it */
 327 #if defined(cpu_list)
 328         cpu_list();
 329 #endif
 330         exit(EXIT_FAILURE);
 331     }
 332 }
 333
 334 static void handle_arg_guest_base(const char *arg)
 335 {
 336     guest_base = strtol(arg, NULL, 0);
 337     have_guest_base = true;
 338 }
 339
 340 static void handle_arg_reserved_va(const char *arg)
 341 {
 342     char *p;
 343     int shift = 0;
 344     reserved_va = strtoul(arg, &p, 0);
 345     switch (*p) {
 346     case 'k':
 347     case 'K':
 348         shift = 10;
 349         break;
 350     case 'M':
 351         shift = 20;
 352         break;
 353     case 'G':
 354         shift = 30;
 355         break;
 356     }
 357     if (shift) {
 358         unsigned long unshifted = reserved_va;
 359         p++;
 360         reserved_va <<= shift;
 361         if (reserved_va >> shift != unshifted) {
 362             fprintf(stderr, "Reserved virtual address too big\n");
 363             exit(EXIT_FAILURE);
 364         }
 365     }
 366     if (*p) {
 367         fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
 368         exit(EXIT_FAILURE);
 369     }
 370 }
 371
 372 static void handle_arg_singlestep(const char *arg)
 373 {
 374     singlestep = 1;
 375 }
 376
 377 static void handle_arg_strace(const char *arg)
 378 {
 379     enable_strace = true;
 380 }
 381
 382 static void handle_arg_version(const char *arg)
 383 {
 384     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 385            "\n" QEMU_COPYRIGHT "\n");
 386     exit(EXIT_SUCCESS);
 387 }
 388
 389 static void handle_arg_trace(const char *arg)
 390 {
 391     trace_opt_parse(arg);
 392 }
 393
 394 #if defined(TARGET_XTENSA)
 395 static void handle_arg_abi_call0(const char *arg)
 396 {
 397     xtensa_set_abi_call0();
 398 }
 399 #endif
 400
 401 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
 402
 403 #ifdef CONFIG_PLUGIN
 404 static void handle_arg_plugin(const char *arg)
 405 {
 406     qemu_plugin_opt_parse(arg, &plugins);
 407 }
 408 #endif
 409
 410 struct qemu_argument {
 411     const char *argv;
 412     const char *env;
 413     bool has_arg;
 414     void (*handle_opt)(const char *arg);
 415     const char *example;
 416     const char *help;
 417 };
 418
 419 static const struct qemu_argument arg_table[] = {
 420     {"h",          "",                 false, handle_arg_help,
 421      "",           "print this help"},
 422     {"help",       "",                 false, handle_arg_help,
 423      "",           ""},
 424     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 425      "port",       "wait gdb connection to 'port'"},
 426     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 427      "path",       "set the elf interpreter prefix to 'path'"},
 428     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 429      "size",       "set the stack size to 'size' bytes"},
 430     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 431      "model",      "select CPU (-cpu help for list)"},
 432     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 433      "var=value",  "sets targets environment variable (see below)"},
 434     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 435      "var",        "unsets targets environment variable (see below)"},
 436     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 437      "argv0",      "forces target process argv[0] to be 'argv0'"},
 438     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 439      "uname",      "set qemu uname release string to 'uname'"},
 440     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 441      "address",    "set guest_base address to 'address'"},
 442     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 443      "size",       "reserve 'size' bytes for guest virtual address space"},
 444     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 445      "item[,...]", "enable logging of specified items "
 446      "(use '-d help' for a list of items)"},
 447     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 448      "range[,...]","filter logging based on address range"},
 449     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 450      "logfile",     "write logs to 'logfile' (default stderr)"},
 451     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 452      "pagesize",   "set the host page size to 'pagesize'"},
 453     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 454      "",           "run in singlestep mode"},
 455     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 456      "",           "log system calls"},
 457     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_seed,
 458      "",           "Seed for pseudo-random number generator"},
 459     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 460      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 461 #ifdef CONFIG_PLUGIN
 462     {"plugin",     "QEMU_PLUGIN",      true,  handle_arg_plugin,
 463      "",           "[file=]<file>[,arg=<string>]"},
 464 #endif
 465     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 466      "",           "display version information and exit"},
 467 #if defined(TARGET_XTENSA)
 468     {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
 469      "",           "assume CALL0 Xtensa ABI"},
 470 #endif
 471     {NULL, NULL, false, NULL, NULL, NULL}
 472 };
 473
 474 static void usage(int exitcode)
 475 {
 476     const struct qemu_argument *arginfo;
 477     int maxarglen;
 478     int maxenvlen;
 479
 480     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 481            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 482            "\n"
 483            "Options and associated environment variables:\n"
 484            "\n");
 485
 486     /* Calculate column widths. We must always have at least enough space
 487      * for the column header.
 488      */
 489     maxarglen = strlen("Argument");
 490     maxenvlen = strlen("Env-variable");
 491
 492     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 493         int arglen = strlen(arginfo->argv);
 494         if (arginfo->has_arg) {
 495             arglen += strlen(arginfo->example) + 1;
 496         }
 497         if (strlen(arginfo->env) > maxenvlen) {
 498             maxenvlen = strlen(arginfo->env);
 499         }
 500         if (arglen > maxarglen) {
 501             maxarglen = arglen;
 502         }
 503     }
 504
 505     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 506             maxenvlen, "Env-variable");
 507
 508     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 509         if (arginfo->has_arg) {
 510             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 511                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 512                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 513         } else {
 514             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 515                     maxenvlen, arginfo->env,
 516                     arginfo->help);
 517         }
 518     }
 519
 520     printf("\n"
 521            "Defaults:\n"
 522            "QEMU_LD_PREFIX  = %s\n"
 523            "QEMU_STACK_SIZE = %ld byte\n",
 524            interp_prefix,
 525            guest_stack_size);
 526
 527     printf("\n"
 528            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 529            "QEMU_UNSET_ENV environment variables to set and unset\n"
 530            "environment variables for the target process.\n"
 531            "It is possible to provide several variables by separating them\n"
 532            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 533            "provide the -E and -U options multiple times.\n"
 534            "The following lines are equivalent:\n"
 535            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 536            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 537            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 538            "Note that if you provide several changes to a single variable\n"
 539            "the last change will stay in effect.\n"
 540            "\n"
 541            QEMU_HELP_BOTTOM "\n");
 542
 543     exit(exitcode);
 544 }
 545
 546 static int parse_args(int argc, char **argv)
 547 {
 548     const char *r;
 549     int optind;
 550     const struct qemu_argument *arginfo;
 551
 552     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 553         if (arginfo->env == NULL) {
 554             continue;
 555         }
 556
 557         r = getenv(arginfo->env);
 558         if (r != NULL) {
 559             arginfo->handle_opt(r);
 560         }
 561     }
 562
 563     optind = 1;
 564     for (;;) {
 565         if (optind >= argc) {
 566             break;
 567         }
 568         r = argv[optind];
 569         if (r[0] != '-') {
 570             break;
 571         }
 572         optind++;
 573         r++;
 574         if (!strcmp(r, "-")) {
 575             break;
 576         }
 577         /* Treat --foo the same as -foo.  */
 578         if (r[0] == '-') {
 579             r++;
 580         }
 581
 582         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 583             if (!strcmp(r, arginfo->argv)) {
 584                 if (arginfo->has_arg) {
 585                     if (optind >= argc) {
 586                         (void) fprintf(stderr,
 587                             "qemu: missing argument for option '%s'\n", r);
 588                         exit(EXIT_FAILURE);
 589                     }
 590                     arginfo->handle_opt(argv[optind]);
 591                     optind++;
 592                 } else {
 593                     arginfo->handle_opt(NULL);
 594                 }
 595                 break;
 596             }
 597         }
 598
 599         /* no option matched the current argv */
 600         if (arginfo->handle_opt == NULL) {
 601             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 602             exit(EXIT_FAILURE);
 603         }
 604     }
 605
 606     if (optind >= argc) {
 607         (void) fprintf(stderr, "qemu: no user program specified\n");
 608         exit(EXIT_FAILURE);
 609     }
 610
 611     exec_path = argv[optind];
 612
 613     return optind;
 614 }
 615
 616 int main(int argc, char **argv, char **envp)
 617 {
 618     struct target_pt_regs regs1, *regs = &regs1;
 619     struct image_info info1, *info = &info1;
 620     struct linux_binprm bprm;
 621     TaskState *ts;
 622     CPUArchState *env;
 623     CPUState *cpu;
 624     int optind;
 625     char **target_environ, **wrk;
 626     char **target_argv;
 627     int target_argc;
 628     int i;
 629     int ret;
 630     int execfd;
 631     int log_mask;
 632     unsigned long max_reserved_va;
 633
 634     error_init(argv[0]);
 635     module_call_init(MODULE_INIT_TRACE);
 636     qemu_init_cpu_list();
 637     module_call_init(MODULE_INIT_QOM);
 638
 639     envlist = envlist_create();
 640
 641     /* add current environment into the list */
 642     for (wrk = environ; *wrk != NULL; wrk++) {
 643         (void) envlist_setenv(envlist, *wrk);
 644     }
 645
 646     /* Read the stack limit from the kernel.  If it's "unlimited",
 647        then we can do little else besides use the default.  */
 648     {
 649         struct rlimit lim;
 650         if (getrlimit(RLIMIT_STACK, &lim) == 0
 651             && lim.rlim_cur != RLIM_INFINITY
 652             && lim.rlim_cur == (target_long)lim.rlim_cur) {
 653             guest_stack_size = lim.rlim_cur;
 654         }
 655     }
 656
 657     cpu_model = NULL;
 658
 659     qemu_add_opts(&qemu_trace_opts);
 660     qemu_plugin_add_opts();
 661
 662     optind = parse_args(argc, argv);
 663
 664     log_mask = last_log_mask | (enable_strace ? LOG_STRACE : 0);
 665     if (log_mask) {
 666         qemu_log_needs_buffers();
 667         qemu_set_log(log_mask);
 668     }
 669
 670     if (!trace_init_backends()) {
 671         exit(1);
 672     }
 673     trace_init_file();
 674     if (qemu_plugin_load_list(&plugins)) {
 675         exit(1);
 676     }
 677
 678     /* Zero out regs */
 679     memset(regs, 0, sizeof(struct target_pt_regs));
 680
 681     /* Zero out image_info */
 682     memset(info, 0, sizeof(struct image_info));
 683
 684     memset(&bprm, 0, sizeof (bprm));
 685
 686     /* Scan interp_prefix dir for replacement files. */
 687     init_paths(interp_prefix);
 688
 689     init_qemu_uname_release();
 690
 691     execfd = qemu_getauxval(AT_EXECFD);
 692     if (execfd == 0) {
 693         execfd = open(exec_path, O_RDONLY);
 694         if (execfd < 0) {
 695             printf("Error while loading %s: %s\n", exec_path, strerror(errno));
 696             _exit(EXIT_FAILURE);
 697         }
 698     }
 699
 700     if (cpu_model == NULL) {
 701         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 702     }
 703     cpu_type = parse_cpu_option(cpu_model);
 704
 705     /* init tcg before creating CPUs and to get qemu_host_page_size */
 706     tcg_exec_init(0);
 707
 708     cpu = cpu_create(cpu_type);
 709     env = cpu->env_ptr;
 710     cpu_reset(cpu);
 711     thread_cpu = cpu;
 712
 713     /*
 714      * Reserving too much vm space via mmap can run into problems
 715      * with rlimits, oom due to page table creation, etc.  We will
 716      * still try it, if directed by the command-line option, but
 717      * not by default.
 718      */
 719     max_reserved_va = MAX_RESERVED_VA(cpu);
 720     if (reserved_va != 0) {
 721         if (max_reserved_va && reserved_va > max_reserved_va) {
 722             fprintf(stderr, "Reserved virtual address too big\n");
 723             exit(EXIT_FAILURE);
 724         }
 725     } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
 726         /*
 727          * reserved_va must be aligned with the host page size
 728          * as it is used with mmap()
 729          */
 730         reserved_va = max_reserved_va & qemu_host_page_mask;
 731     }
 732
 733     {
 734         Error *err = NULL;
 735         if (seed_optarg != NULL) {
 736             qemu_guest_random_seed_main(seed_optarg, &err);
 737         } else {
 738             qcrypto_init(&err);
 739         }
 740         if (err) {
 741             error_reportf_err(err, "cannot initialize crypto: ");
 742             exit(1);
 743         }
 744     }
 745
 746     target_environ = envlist_to_environ(envlist, NULL);
 747     envlist_free(envlist);
 748
 749     /*
 750      * Read in mmap_min_addr kernel parameter.  This value is used
 751      * When loading the ELF image to determine whether guest_base
 752      * is needed.  It is also used in mmap_find_vma.
 753      */
 754     {
 755         FILE *fp;
 756
 757         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 758             unsigned long tmp;
 759             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
 760                 mmap_min_addr = tmp;
 761                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
 762                               mmap_min_addr);
 763             }
 764             fclose(fp);
 765         }
 766     }
 767
 768     /*
 769      * We prefer to not make NULL pointers accessible to QEMU.
 770      * If we're in a chroot with no /proc, fall back to 1 page.
 771      */
 772     if (mmap_min_addr == 0) {
 773         mmap_min_addr = qemu_host_page_size;
 774         qemu_log_mask(CPU_LOG_PAGE,
 775                       "host mmap_min_addr=0x%lx (fallback)\n",
 776                       mmap_min_addr);
 777     }
 778
 779     /*
 780      * Prepare copy of argv vector for target.
 781      */
 782     target_argc = argc - optind;
 783     target_argv = calloc(target_argc + 1, sizeof (char *));
 784     if (target_argv == NULL) {
 785         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 786         exit(EXIT_FAILURE);
 787     }
 788
 789     /*
 790      * If argv0 is specified (using '-0' switch) we replace
 791      * argv[0] pointer with the given one.
 792      */
 793     i = 0;
 794     if (argv0 != NULL) {
 795         target_argv[i++] = strdup(argv0);
 796     }
 797     for (; i < target_argc; i++) {
 798         target_argv[i] = strdup(argv[optind + i]);
 799     }
 800     target_argv[target_argc] = NULL;
 801
 802     ts = g_new0(TaskState, 1);
 803     init_task_state(ts);
 804     /* build Task State */
 805     ts->info = info;
 806     ts->bprm = &bprm;
 807     cpu->opaque = ts;
 808     task_settid(ts);
 809
 810     ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
 811         info, &bprm);
 812     if (ret != 0) {
 813         printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
 814         _exit(EXIT_FAILURE);
 815     }
 816
 817     for (wrk = target_environ; *wrk; wrk++) {
 818         g_free(*wrk);
 819     }
 820
 821     g_free(target_environ);
 822
 823     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 824         qemu_log("guest_base  0x%lx\n", guest_base);
 825         log_page_dump("binary load");
 826
 827         qemu_log("start_brk   0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
 828         qemu_log("end_code    0x" TARGET_ABI_FMT_lx "\n", info->end_code);
 829         qemu_log("start_code  0x" TARGET_ABI_FMT_lx "\n", info->start_code);
 830         qemu_log("start_data  0x" TARGET_ABI_FMT_lx "\n", info->start_data);
 831         qemu_log("end_data    0x" TARGET_ABI_FMT_lx "\n", info->end_data);
 832         qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n", info->start_stack);
 833         qemu_log("brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 834         qemu_log("entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 835         qemu_log("argv_start  0x" TARGET_ABI_FMT_lx "\n", info->arg_start);
 836         qemu_log("env_start   0x" TARGET_ABI_FMT_lx "\n",
 837                  info->arg_end + (abi_ulong)sizeof(abi_ulong));
 838         qemu_log("auxv_start  0x" TARGET_ABI_FMT_lx "\n", info->saved_auxv);
 839     }
 840
 841     target_set_brk(info->brk);
 842     syscall_init();
 843     signal_init();
 844
 845     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 846        generating the prologue until now so that the prologue can take
 847        the real value of GUEST_BASE into account.  */
 848     tcg_prologue_init(tcg_ctx);
 849     tcg_region_init();
 850
 851     target_cpu_copy_regs(env, regs);
 852
 853     if (gdbstub) {
 854         if (gdbserver_start(gdbstub) < 0) {
 855             fprintf(stderr, "qemu: could not open gdbserver on %s\n",
 856                     gdbstub);
 857             exit(EXIT_FAILURE);
 858         }
 859         gdb_handlesig(cpu, 0);
 860     }
 861     cpu_loop(env);
 862     /* never exits */
 863     return 0;
 864 }