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 char *trace_file;
 390 static void handle_arg_trace(const char *arg)
 391 {
 392     g_free(trace_file);
 393     trace_file = trace_opt_parse(arg);
 394 }
 395
 396 #if defined(TARGET_XTENSA)
 397 static void handle_arg_abi_call0(const char *arg)
 398 {
 399     xtensa_set_abi_call0();
 400 }
 401 #endif
 402
 403 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
 404
 405 #ifdef CONFIG_PLUGIN
 406 static void handle_arg_plugin(const char *arg)
 407 {
 408     qemu_plugin_opt_parse(arg, &plugins);
 409 }
 410 #endif
 411
 412 struct qemu_argument {
 413     const char *argv;
 414     const char *env;
 415     bool has_arg;
 416     void (*handle_opt)(const char *arg);
 417     const char *example;
 418     const char *help;
 419 };
 420
 421 static const struct qemu_argument arg_table[] = {
 422     {"h",          "",                 false, handle_arg_help,
 423      "",           "print this help"},
 424     {"help",       "",                 false, handle_arg_help,
 425      "",           ""},
 426     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 427      "port",       "wait gdb connection to 'port'"},
 428     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 429      "path",       "set the elf interpreter prefix to 'path'"},
 430     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 431      "size",       "set the stack size to 'size' bytes"},
 432     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 433      "model",      "select CPU (-cpu help for list)"},
 434     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 435      "var=value",  "sets targets environment variable (see below)"},
 436     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 437      "var",        "unsets targets environment variable (see below)"},
 438     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 439      "argv0",      "forces target process argv[0] to be 'argv0'"},
 440     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 441      "uname",      "set qemu uname release string to 'uname'"},
 442     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 443      "address",    "set guest_base address to 'address'"},
 444     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 445      "size",       "reserve 'size' bytes for guest virtual address space"},
 446     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 447      "item[,...]", "enable logging of specified items "
 448      "(use '-d help' for a list of items)"},
 449     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 450      "range[,...]","filter logging based on address range"},
 451     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 452      "logfile",     "write logs to 'logfile' (default stderr)"},
 453     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 454      "pagesize",   "set the host page size to 'pagesize'"},
 455     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 456      "",           "run in singlestep mode"},
 457     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 458      "",           "log system calls"},
 459     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_seed,
 460      "",           "Seed for pseudo-random number generator"},
 461     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 462      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 463 #ifdef CONFIG_PLUGIN
 464     {"plugin",     "QEMU_PLUGIN",      true,  handle_arg_plugin,
 465      "",           "[file=]<file>[,arg=<string>]"},
 466 #endif
 467     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 468      "",           "display version information and exit"},
 469 #if defined(TARGET_XTENSA)
 470     {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
 471      "",           "assume CALL0 Xtensa ABI"},
 472 #endif
 473     {NULL, NULL, false, NULL, NULL, NULL}
 474 };
 475
 476 static void usage(int exitcode)
 477 {
 478     const struct qemu_argument *arginfo;
 479     int maxarglen;
 480     int maxenvlen;
 481
 482     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 483            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 484            "\n"
 485            "Options and associated environment variables:\n"
 486            "\n");
 487
 488     /* Calculate column widths. We must always have at least enough space
 489      * for the column header.
 490      */
 491     maxarglen = strlen("Argument");
 492     maxenvlen = strlen("Env-variable");
 493
 494     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 495         int arglen = strlen(arginfo->argv);
 496         if (arginfo->has_arg) {
 497             arglen += strlen(arginfo->example) + 1;
 498         }
 499         if (strlen(arginfo->env) > maxenvlen) {
 500             maxenvlen = strlen(arginfo->env);
 501         }
 502         if (arglen > maxarglen) {
 503             maxarglen = arglen;
 504         }
 505     }
 506
 507     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 508             maxenvlen, "Env-variable");
 509
 510     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 511         if (arginfo->has_arg) {
 512             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 513                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 514                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 515         } else {
 516             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 517                     maxenvlen, arginfo->env,
 518                     arginfo->help);
 519         }
 520     }
 521
 522     printf("\n"
 523            "Defaults:\n"
 524            "QEMU_LD_PREFIX  = %s\n"
 525            "QEMU_STACK_SIZE = %ld byte\n",
 526            interp_prefix,
 527            guest_stack_size);
 528
 529     printf("\n"
 530            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 531            "QEMU_UNSET_ENV environment variables to set and unset\n"
 532            "environment variables for the target process.\n"
 533            "It is possible to provide several variables by separating them\n"
 534            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 535            "provide the -E and -U options multiple times.\n"
 536            "The following lines are equivalent:\n"
 537            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 538            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 539            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 540            "Note that if you provide several changes to a single variable\n"
 541            "the last change will stay in effect.\n"
 542            "\n"
 543            QEMU_HELP_BOTTOM "\n");
 544
 545     exit(exitcode);
 546 }
 547
 548 static int parse_args(int argc, char **argv)
 549 {
 550     const char *r;
 551     int optind;
 552     const struct qemu_argument *arginfo;
 553
 554     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 555         if (arginfo->env == NULL) {
 556             continue;
 557         }
 558
 559         r = getenv(arginfo->env);
 560         if (r != NULL) {
 561             arginfo->handle_opt(r);
 562         }
 563     }
 564
 565     optind = 1;
 566     for (;;) {
 567         if (optind >= argc) {
 568             break;
 569         }
 570         r = argv[optind];
 571         if (r[0] != '-') {
 572             break;
 573         }
 574         optind++;
 575         r++;
 576         if (!strcmp(r, "-")) {
 577             break;
 578         }
 579         /* Treat --foo the same as -foo.  */
 580         if (r[0] == '-') {
 581             r++;
 582         }
 583
 584         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 585             if (!strcmp(r, arginfo->argv)) {
 586                 if (arginfo->has_arg) {
 587                     if (optind >= argc) {
 588                         (void) fprintf(stderr,
 589                             "qemu: missing argument for option '%s'\n", r);
 590                         exit(EXIT_FAILURE);
 591                     }
 592                     arginfo->handle_opt(argv[optind]);
 593                     optind++;
 594                 } else {
 595                     arginfo->handle_opt(NULL);
 596                 }
 597                 break;
 598             }
 599         }
 600
 601         /* no option matched the current argv */
 602         if (arginfo->handle_opt == NULL) {
 603             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 604             exit(EXIT_FAILURE);
 605         }
 606     }
 607
 608     if (optind >= argc) {
 609         (void) fprintf(stderr, "qemu: no user program specified\n");
 610         exit(EXIT_FAILURE);
 611     }
 612
 613     exec_path = argv[optind];
 614
 615     return optind;
 616 }
 617
 618 int main(int argc, char **argv, char **envp)
 619 {
 620     struct target_pt_regs regs1, *regs = &regs1;
 621     struct image_info info1, *info = &info1;
 622     struct linux_binprm bprm;
 623     TaskState *ts;
 624     CPUArchState *env;
 625     CPUState *cpu;
 626     int optind;
 627     char **target_environ, **wrk;
 628     char **target_argv;
 629     int target_argc;
 630     int i;
 631     int ret;
 632     int execfd;
 633     int log_mask;
 634     unsigned long max_reserved_va;
 635
 636     error_init(argv[0]);
 637     module_call_init(MODULE_INIT_TRACE);
 638     qemu_init_cpu_list();
 639     module_call_init(MODULE_INIT_QOM);
 640
 641     envlist = envlist_create();
 642
 643     /* add current environment into the list */
 644     for (wrk = environ; *wrk != NULL; wrk++) {
 645         (void) envlist_setenv(envlist, *wrk);
 646     }
 647
 648     /* Read the stack limit from the kernel.  If it's "unlimited",
 649        then we can do little else besides use the default.  */
 650     {
 651         struct rlimit lim;
 652         if (getrlimit(RLIMIT_STACK, &lim) == 0
 653             && lim.rlim_cur != RLIM_INFINITY
 654             && lim.rlim_cur == (target_long)lim.rlim_cur) {
 655             guest_stack_size = lim.rlim_cur;
 656         }
 657     }
 658
 659     cpu_model = NULL;
 660
 661     qemu_add_opts(&qemu_trace_opts);
 662     qemu_plugin_add_opts();
 663
 664     optind = parse_args(argc, argv);
 665
 666     log_mask = last_log_mask | (enable_strace ? LOG_STRACE : 0);
 667     if (log_mask) {
 668         qemu_log_needs_buffers();
 669         qemu_set_log(log_mask);
 670     }
 671
 672     if (!trace_init_backends()) {
 673         exit(1);
 674     }
 675     trace_init_file(trace_file);
 676     if (qemu_plugin_load_list(&plugins)) {
 677         exit(1);
 678     }
 679
 680     /* Zero out regs */
 681     memset(regs, 0, sizeof(struct target_pt_regs));
 682
 683     /* Zero out image_info */
 684     memset(info, 0, sizeof(struct image_info));
 685
 686     memset(&bprm, 0, sizeof (bprm));
 687
 688     /* Scan interp_prefix dir for replacement files. */
 689     init_paths(interp_prefix);
 690
 691     init_qemu_uname_release();
 692
 693     execfd = qemu_getauxval(AT_EXECFD);
 694     if (execfd == 0) {
 695         execfd = open(exec_path, O_RDONLY);
 696         if (execfd < 0) {
 697             printf("Error while loading %s: %s\n", exec_path, strerror(errno));
 698             _exit(EXIT_FAILURE);
 699         }
 700     }
 701
 702     if (cpu_model == NULL) {
 703         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 704     }
 705     cpu_type = parse_cpu_option(cpu_model);
 706
 707     /* init tcg before creating CPUs and to get qemu_host_page_size */
 708     tcg_exec_init(0);
 709
 710     cpu = cpu_create(cpu_type);
 711     env = cpu->env_ptr;
 712     cpu_reset(cpu);
 713     thread_cpu = cpu;
 714
 715     /*
 716      * Reserving too much vm space via mmap can run into problems
 717      * with rlimits, oom due to page table creation, etc.  We will
 718      * still try it, if directed by the command-line option, but
 719      * not by default.
 720      */
 721     max_reserved_va = MAX_RESERVED_VA(cpu);
 722     if (reserved_va != 0) {
 723         if (max_reserved_va && reserved_va > max_reserved_va) {
 724             fprintf(stderr, "Reserved virtual address too big\n");
 725             exit(EXIT_FAILURE);
 726         }
 727     } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
 728         /*
 729          * reserved_va must be aligned with the host page size
 730          * as it is used with mmap()
 731          */
 732         reserved_va = max_reserved_va & qemu_host_page_mask;
 733     }
 734
 735     {
 736         Error *err = NULL;
 737         if (seed_optarg != NULL) {
 738             qemu_guest_random_seed_main(seed_optarg, &err);
 739         } else {
 740             qcrypto_init(&err);
 741         }
 742         if (err) {
 743             error_reportf_err(err, "cannot initialize crypto: ");
 744             exit(1);
 745         }
 746     }
 747
 748     target_environ = envlist_to_environ(envlist, NULL);
 749     envlist_free(envlist);
 750
 751     /*
 752      * Read in mmap_min_addr kernel parameter.  This value is used
 753      * When loading the ELF image to determine whether guest_base
 754      * is needed.  It is also used in mmap_find_vma.
 755      */
 756     {
 757         FILE *fp;
 758
 759         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 760             unsigned long tmp;
 761             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
 762                 mmap_min_addr = tmp;
 763                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
 764                               mmap_min_addr);
 765             }
 766             fclose(fp);
 767         }
 768     }
 769
 770     /*
 771      * We prefer to not make NULL pointers accessible to QEMU.
 772      * If we're in a chroot with no /proc, fall back to 1 page.
 773      */
 774     if (mmap_min_addr == 0) {
 775         mmap_min_addr = qemu_host_page_size;
 776         qemu_log_mask(CPU_LOG_PAGE,
 777                       "host mmap_min_addr=0x%lx (fallback)\n",
 778                       mmap_min_addr);
 779     }
 780
 781     /*
 782      * Prepare copy of argv vector for target.
 783      */
 784     target_argc = argc - optind;
 785     target_argv = calloc(target_argc + 1, sizeof (char *));
 786     if (target_argv == NULL) {
 787         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 788         exit(EXIT_FAILURE);
 789     }
 790
 791     /*
 792      * If argv0 is specified (using '-0' switch) we replace
 793      * argv[0] pointer with the given one.
 794      */
 795     i = 0;
 796     if (argv0 != NULL) {
 797         target_argv[i++] = strdup(argv0);
 798     }
 799     for (; i < target_argc; i++) {
 800         target_argv[i] = strdup(argv[optind + i]);
 801     }
 802     target_argv[target_argc] = NULL;
 803
 804     ts = g_new0(TaskState, 1);
 805     init_task_state(ts);
 806     /* build Task State */
 807     ts->info = info;
 808     ts->bprm = &bprm;
 809     cpu->opaque = ts;
 810     task_settid(ts);
 811
 812     ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
 813         info, &bprm);
 814     if (ret != 0) {
 815         printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
 816         _exit(EXIT_FAILURE);
 817     }
 818
 819     for (wrk = target_environ; *wrk; wrk++) {
 820         g_free(*wrk);
 821     }
 822
 823     g_free(target_environ);
 824
 825     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 826         qemu_log("guest_base  0x%lx\n", guest_base);
 827         log_page_dump("binary load");
 828
 829         qemu_log("start_brk   0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
 830         qemu_log("end_code    0x" TARGET_ABI_FMT_lx "\n", info->end_code);
 831         qemu_log("start_code  0x" TARGET_ABI_FMT_lx "\n", info->start_code);
 832         qemu_log("start_data  0x" TARGET_ABI_FMT_lx "\n", info->start_data);
 833         qemu_log("end_data    0x" TARGET_ABI_FMT_lx "\n", info->end_data);
 834         qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n", info->start_stack);
 835         qemu_log("brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 836         qemu_log("entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 837         qemu_log("argv_start  0x" TARGET_ABI_FMT_lx "\n", info->arg_start);
 838         qemu_log("env_start   0x" TARGET_ABI_FMT_lx "\n",
 839                  info->arg_end + (abi_ulong)sizeof(abi_ulong));
 840         qemu_log("auxv_start  0x" TARGET_ABI_FMT_lx "\n", info->saved_auxv);
 841     }
 842
 843     target_set_brk(info->brk);
 844     syscall_init();
 845     signal_init();
 846
 847     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 848        generating the prologue until now so that the prologue can take
 849        the real value of GUEST_BASE into account.  */
 850     tcg_prologue_init(tcg_ctx);
 851     tcg_region_init();
 852
 853     target_cpu_copy_regs(env, regs);
 854
 855     if (gdbstub) {
 856         if (gdbserver_start(gdbstub) < 0) {
 857             fprintf(stderr, "qemu: could not open gdbserver on %s\n",
 858                     gdbstub);
 859             exit(EXIT_FAILURE);
 860         }
 861         gdb_handlesig(cpu, 0);
 862     }
 863     cpu_loop(env);
 864     /* never exits */
 865     return 0;
 866 }