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 "gdbstub/user.h"
  44 #include "tcg/tcg.h"
  45 #include "qemu/timer.h"
  46 #include "qemu/envlist.h"
  47 #include "qemu/guest-random.h"
  48 #include "elf.h"
  49 #include "trace/control.h"
  50 #include "target_elf.h"
  51 #include "cpu_loop-common.h"
  52 #include "crypto/init.h"
  53 #include "fd-trans.h"
  54 #include "signal-common.h"
  55 #include "loader.h"
  56 #include "user-mmap.h"
  57 #include "accel/tcg/perf.h"
  58
  59 #ifdef CONFIG_SEMIHOSTING
  60 #include "semihosting/semihost.h"
  61 #endif
  62
  63 #ifndef AT_FLAGS_PRESERVE_ARGV0
  64 #define AT_FLAGS_PRESERVE_ARGV0_BIT 0
  65 #define AT_FLAGS_PRESERVE_ARGV0 (1 << AT_FLAGS_PRESERVE_ARGV0_BIT)
  66 #endif
  67
  68 char *exec_path;
  69
  70 int singlestep;
  71 static const char *argv0;
  72 static const char *gdbstub;
  73 static envlist_t *envlist;
  74 static const char *cpu_model;
  75 static const char *cpu_type;
  76 static const char *seed_optarg;
  77 unsigned long mmap_min_addr;
  78 uintptr_t guest_base;
  79 bool have_guest_base;
  80
  81 /*
  82  * Used to implement backwards-compatibility for the `-strace`, and
  83  * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by
  84  * -strace, or vice versa.
  85  */
  86 static bool enable_strace;
  87
  88 /*
  89  * The last log mask given by the user in an environment variable or argument.
  90  * Used to support command line arguments overriding environment variables.
  91  */
  92 static int last_log_mask;
  93 static const char *last_log_filename;
  94
  95 /*
  96  * When running 32-on-64 we should make sure we can fit all of the possible
  97  * guest address space into a contiguous chunk of virtual host memory.
  98  *
  99  * This way we will never overlap with our own libraries or binaries or stack
 100  * or anything else that QEMU maps.
 101  *
 102  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
 103  * of the address for the kernel.  Some cpus rely on this and user space
 104  * uses the high bit(s) for pointer tagging and the like.  For them, we
 105  * must preserve the expected address space.
 106  */
 107 #ifndef MAX_RESERVED_VA
 108 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
 109 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
 110       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
 111 /* There are a number of places where we assign reserved_va to a variable
 112    of type abi_ulong and expect it to fit.  Avoid the last page.  */
 113 #   define MAX_RESERVED_VA(CPU)  (0xfffffffful & TARGET_PAGE_MASK)
 114 #  else
 115 #   define MAX_RESERVED_VA(CPU)  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
 116 #  endif
 117 # else
 118 #  define MAX_RESERVED_VA(CPU)  0
 119 # endif
 120 #endif
 121
 122 unsigned long reserved_va;
 123
 124 static void usage(int exitcode);
 125
 126 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
 127 const char *qemu_uname_release;
 128
 129 #if !defined(TARGET_DEFAULT_STACK_SIZE)
 130 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
 131    we allocate a bigger stack. Need a better solution, for example
 132    by remapping the process stack directly at the right place */
 133 #define TARGET_DEFAULT_STACK_SIZE       8 * 1024 * 1024UL
 134 #endif
 135
 136 unsigned long guest_stack_size = TARGET_DEFAULT_STACK_SIZE;
 137
 138 /***********************************************************/
 139 /* Helper routines for implementing atomic operations.  */
 140
 141 /* Make sure everything is in a consistent state for calling fork().  */
 142 void fork_start(void)
 143 {
 144     start_exclusive();
 145     mmap_fork_start();
 146     cpu_list_lock();
 147     qemu_plugin_user_prefork_lock();
 148 }
 149
 150 void fork_end(int child)
 151 {
 152     qemu_plugin_user_postfork(child);
 153     mmap_fork_end(child);
 154     if (child) {
 155         CPUState *cpu, *next_cpu;
 156         /* Child processes created by fork() only have a single thread.
 157            Discard information about the parent threads.  */
 158         CPU_FOREACH_SAFE(cpu, next_cpu) {
 159             if (cpu != thread_cpu) {
 160                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 161             }
 162         }
 163         qemu_init_cpu_list();
 164         gdbserver_fork(thread_cpu);
 165     } else {
 166         cpu_list_unlock();
 167     }
 168     /*
 169      * qemu_init_cpu_list() reinitialized the child exclusive state, but we
 170      * also need to keep current_cpu consistent, so call end_exclusive() for
 171      * both child and parent.
 172      */
 173     end_exclusive();
 174 }
 175
 176 __thread CPUState *thread_cpu;
 177
 178 bool qemu_cpu_is_self(CPUState *cpu)
 179 {
 180     return thread_cpu == cpu;
 181 }
 182
 183 void qemu_cpu_kick(CPUState *cpu)
 184 {
 185     cpu_exit(cpu);
 186 }
 187
 188 void task_settid(TaskState *ts)
 189 {
 190     if (ts->ts_tid == 0) {
 191         ts->ts_tid = (pid_t)syscall(SYS_gettid);
 192     }
 193 }
 194
 195 void stop_all_tasks(void)
 196 {
 197     /*
 198      * We trust that when using NPTL, start_exclusive()
 199      * handles thread stopping correctly.
 200      */
 201     start_exclusive();
 202 }
 203
 204 /* Assumes contents are already zeroed.  */
 205 void init_task_state(TaskState *ts)
 206 {
 207     long ticks_per_sec;
 208     struct timespec bt;
 209
 210     ts->used = 1;
 211     ts->sigaltstack_used = (struct target_sigaltstack) {
 212         .ss_sp = 0,
 213         .ss_size = 0,
 214         .ss_flags = TARGET_SS_DISABLE,
 215     };
 216
 217     /* Capture task start time relative to system boot */
 218
 219     ticks_per_sec = sysconf(_SC_CLK_TCK);
 220
 221     if ((ticks_per_sec > 0) && !clock_gettime(CLOCK_BOOTTIME, &bt)) {
 222         /* start_boottime is expressed in clock ticks */
 223         ts->start_boottime = bt.tv_sec * (uint64_t) ticks_per_sec;
 224         ts->start_boottime += bt.tv_nsec * (uint64_t) ticks_per_sec /
 225                               NANOSECONDS_PER_SECOND;
 226     }
 227 }
 228
 229 CPUArchState *cpu_copy(CPUArchState *env)
 230 {
 231     CPUState *cpu = env_cpu(env);
 232     CPUState *new_cpu = cpu_create(cpu_type);
 233     CPUArchState *new_env = new_cpu->env_ptr;
 234     CPUBreakpoint *bp;
 235
 236     /* Reset non arch specific state */
 237     cpu_reset(new_cpu);
 238
 239     new_cpu->tcg_cflags = cpu->tcg_cflags;
 240     memcpy(new_env, env, sizeof(CPUArchState));
 241
 242     /* Clone all break/watchpoints.
 243        Note: Once we support ptrace with hw-debug register access, make sure
 244        BP_CPU break/watchpoints are handled correctly on clone. */
 245     QTAILQ_INIT(&new_cpu->breakpoints);
 246     QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
 247         cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
 248     }
 249
 250     return new_env;
 251 }
 252
 253 static void handle_arg_help(const char *arg)
 254 {
 255     usage(EXIT_SUCCESS);
 256 }
 257
 258 static void handle_arg_log(const char *arg)
 259 {
 260     last_log_mask = qemu_str_to_log_mask(arg);
 261     if (!last_log_mask) {
 262         qemu_print_log_usage(stdout);
 263         exit(EXIT_FAILURE);
 264     }
 265 }
 266
 267 static void handle_arg_dfilter(const char *arg)
 268 {
 269     qemu_set_dfilter_ranges(arg, &error_fatal);
 270 }
 271
 272 static void handle_arg_log_filename(const char *arg)
 273 {
 274     last_log_filename = arg;
 275 }
 276
 277 static void handle_arg_set_env(const char *arg)
 278 {
 279     char *r, *p, *token;
 280     r = p = strdup(arg);
 281     while ((token = strsep(&p, ",")) != NULL) {
 282         if (envlist_setenv(envlist, token) != 0) {
 283             usage(EXIT_FAILURE);
 284         }
 285     }
 286     free(r);
 287 }
 288
 289 static void handle_arg_unset_env(const char *arg)
 290 {
 291     char *r, *p, *token;
 292     r = p = strdup(arg);
 293     while ((token = strsep(&p, ",")) != NULL) {
 294         if (envlist_unsetenv(envlist, token) != 0) {
 295             usage(EXIT_FAILURE);
 296         }
 297     }
 298     free(r);
 299 }
 300
 301 static void handle_arg_argv0(const char *arg)
 302 {
 303     argv0 = strdup(arg);
 304 }
 305
 306 static void handle_arg_stack_size(const char *arg)
 307 {
 308     char *p;
 309     guest_stack_size = strtoul(arg, &p, 0);
 310     if (guest_stack_size == 0) {
 311         usage(EXIT_FAILURE);
 312     }
 313
 314     if (*p == 'M') {
 315         guest_stack_size *= MiB;
 316     } else if (*p == 'k' || *p == 'K') {
 317         guest_stack_size *= KiB;
 318     }
 319 }
 320
 321 static void handle_arg_ld_prefix(const char *arg)
 322 {
 323     interp_prefix = strdup(arg);
 324 }
 325
 326 static void handle_arg_pagesize(const char *arg)
 327 {
 328     qemu_host_page_size = atoi(arg);
 329     if (qemu_host_page_size == 0 ||
 330         (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 331         fprintf(stderr, "page size must be a power of two\n");
 332         exit(EXIT_FAILURE);
 333     }
 334 }
 335
 336 static void handle_arg_seed(const char *arg)
 337 {
 338     seed_optarg = arg;
 339 }
 340
 341 static void handle_arg_gdb(const char *arg)
 342 {
 343     gdbstub = g_strdup(arg);
 344 }
 345
 346 static void handle_arg_uname(const char *arg)
 347 {
 348     qemu_uname_release = strdup(arg);
 349 }
 350
 351 static void handle_arg_cpu(const char *arg)
 352 {
 353     cpu_model = strdup(arg);
 354     if (cpu_model == NULL || is_help_option(cpu_model)) {
 355         /* XXX: implement xxx_cpu_list for targets that still miss it */
 356 #if defined(cpu_list)
 357         cpu_list();
 358 #endif
 359         exit(EXIT_FAILURE);
 360     }
 361 }
 362
 363 static void handle_arg_guest_base(const char *arg)
 364 {
 365     guest_base = strtol(arg, NULL, 0);
 366     have_guest_base = true;
 367 }
 368
 369 static void handle_arg_reserved_va(const char *arg)
 370 {
 371     char *p;
 372     int shift = 0;
 373     reserved_va = strtoul(arg, &p, 0);
 374     switch (*p) {
 375     case 'k':
 376     case 'K':
 377         shift = 10;
 378         break;
 379     case 'M':
 380         shift = 20;
 381         break;
 382     case 'G':
 383         shift = 30;
 384         break;
 385     }
 386     if (shift) {
 387         unsigned long unshifted = reserved_va;
 388         p++;
 389         reserved_va <<= shift;
 390         if (reserved_va >> shift != unshifted) {
 391             fprintf(stderr, "Reserved virtual address too big\n");
 392             exit(EXIT_FAILURE);
 393         }
 394     }
 395     if (*p) {
 396         fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
 397         exit(EXIT_FAILURE);
 398     }
 399 }
 400
 401 static void handle_arg_singlestep(const char *arg)
 402 {
 403     singlestep = 1;
 404 }
 405
 406 static void handle_arg_strace(const char *arg)
 407 {
 408     enable_strace = true;
 409 }
 410
 411 static void handle_arg_version(const char *arg)
 412 {
 413     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 414            "\n" QEMU_COPYRIGHT "\n");
 415     exit(EXIT_SUCCESS);
 416 }
 417
 418 static void handle_arg_trace(const char *arg)
 419 {
 420     trace_opt_parse(arg);
 421 }
 422
 423 #if defined(TARGET_XTENSA)
 424 static void handle_arg_abi_call0(const char *arg)
 425 {
 426     xtensa_set_abi_call0();
 427 }
 428 #endif
 429
 430 static void handle_arg_perfmap(const char *arg)
 431 {
 432     perf_enable_perfmap();
 433 }
 434
 435 static void handle_arg_jitdump(const char *arg)
 436 {
 437     perf_enable_jitdump();
 438 }
 439
 440 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
 441
 442 #ifdef CONFIG_PLUGIN
 443 static void handle_arg_plugin(const char *arg)
 444 {
 445     qemu_plugin_opt_parse(arg, &plugins);
 446 }
 447 #endif
 448
 449 struct qemu_argument {
 450     const char *argv;
 451     const char *env;
 452     bool has_arg;
 453     void (*handle_opt)(const char *arg);
 454     const char *example;
 455     const char *help;
 456 };
 457
 458 static const struct qemu_argument arg_table[] = {
 459     {"h",          "",                 false, handle_arg_help,
 460      "",           "print this help"},
 461     {"help",       "",                 false, handle_arg_help,
 462      "",           ""},
 463     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 464      "port",       "wait gdb connection to 'port'"},
 465     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 466      "path",       "set the elf interpreter prefix to 'path'"},
 467     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 468      "size",       "set the stack size to 'size' bytes"},
 469     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 470      "model",      "select CPU (-cpu help for list)"},
 471     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 472      "var=value",  "sets targets environment variable (see below)"},
 473     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 474      "var",        "unsets targets environment variable (see below)"},
 475     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 476      "argv0",      "forces target process argv[0] to be 'argv0'"},
 477     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 478      "uname",      "set qemu uname release string to 'uname'"},
 479     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 480      "address",    "set guest_base address to 'address'"},
 481     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 482      "size",       "reserve 'size' bytes for guest virtual address space"},
 483     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 484      "item[,...]", "enable logging of specified items "
 485      "(use '-d help' for a list of items)"},
 486     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 487      "range[,...]","filter logging based on address range"},
 488     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 489      "logfile",     "write logs to 'logfile' (default stderr)"},
 490     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 491      "pagesize",   "set the host page size to 'pagesize'"},
 492     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 493      "",           "run in singlestep mode"},
 494     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 495      "",           "log system calls"},
 496     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_seed,
 497      "",           "Seed for pseudo-random number generator"},
 498     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 499      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 500 #ifdef CONFIG_PLUGIN
 501     {"plugin",     "QEMU_PLUGIN",      true,  handle_arg_plugin,
 502      "",           "[file=]<file>[,<argname>=<argvalue>]"},
 503 #endif
 504     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 505      "",           "display version information and exit"},
 506 #if defined(TARGET_XTENSA)
 507     {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
 508      "",           "assume CALL0 Xtensa ABI"},
 509 #endif
 510     {"perfmap",    "QEMU_PERFMAP",     false, handle_arg_perfmap,
 511      "",           "Generate a /tmp/perf-${pid}.map file for perf"},
 512     {"jitdump",    "QEMU_JITDUMP",     false, handle_arg_jitdump,
 513      "",           "Generate a jit-${pid}.dump file for perf"},
 514     {NULL, NULL, false, NULL, NULL, NULL}
 515 };
 516
 517 static void usage(int exitcode)
 518 {
 519     const struct qemu_argument *arginfo;
 520     int maxarglen;
 521     int maxenvlen;
 522
 523     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 524            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 525            "\n"
 526            "Options and associated environment variables:\n"
 527            "\n");
 528
 529     /* Calculate column widths. We must always have at least enough space
 530      * for the column header.
 531      */
 532     maxarglen = strlen("Argument");
 533     maxenvlen = strlen("Env-variable");
 534
 535     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 536         int arglen = strlen(arginfo->argv);
 537         if (arginfo->has_arg) {
 538             arglen += strlen(arginfo->example) + 1;
 539         }
 540         if (strlen(arginfo->env) > maxenvlen) {
 541             maxenvlen = strlen(arginfo->env);
 542         }
 543         if (arglen > maxarglen) {
 544             maxarglen = arglen;
 545         }
 546     }
 547
 548     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 549             maxenvlen, "Env-variable");
 550
 551     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 552         if (arginfo->has_arg) {
 553             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 554                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 555                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 556         } else {
 557             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 558                     maxenvlen, arginfo->env,
 559                     arginfo->help);
 560         }
 561     }
 562
 563     printf("\n"
 564            "Defaults:\n"
 565            "QEMU_LD_PREFIX  = %s\n"
 566            "QEMU_STACK_SIZE = %ld byte\n",
 567            interp_prefix,
 568            guest_stack_size);
 569
 570     printf("\n"
 571            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 572            "QEMU_UNSET_ENV environment variables to set and unset\n"
 573            "environment variables for the target process.\n"
 574            "It is possible to provide several variables by separating them\n"
 575            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 576            "provide the -E and -U options multiple times.\n"
 577            "The following lines are equivalent:\n"
 578            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 579            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 580            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 581            "Note that if you provide several changes to a single variable\n"
 582            "the last change will stay in effect.\n"
 583            "\n"
 584            QEMU_HELP_BOTTOM "\n");
 585
 586     exit(exitcode);
 587 }
 588
 589 static int parse_args(int argc, char **argv)
 590 {
 591     const char *r;
 592     int optind;
 593     const struct qemu_argument *arginfo;
 594
 595     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 596         if (arginfo->env == NULL) {
 597             continue;
 598         }
 599
 600         r = getenv(arginfo->env);
 601         if (r != NULL) {
 602             arginfo->handle_opt(r);
 603         }
 604     }
 605
 606     optind = 1;
 607     for (;;) {
 608         if (optind >= argc) {
 609             break;
 610         }
 611         r = argv[optind];
 612         if (r[0] != '-') {
 613             break;
 614         }
 615         optind++;
 616         r++;
 617         if (!strcmp(r, "-")) {
 618             break;
 619         }
 620         /* Treat --foo the same as -foo.  */
 621         if (r[0] == '-') {
 622             r++;
 623         }
 624
 625         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 626             if (!strcmp(r, arginfo->argv)) {
 627                 if (arginfo->has_arg) {
 628                     if (optind >= argc) {
 629                         (void) fprintf(stderr,
 630                             "qemu: missing argument for option '%s'\n", r);
 631                         exit(EXIT_FAILURE);
 632                     }
 633                     arginfo->handle_opt(argv[optind]);
 634                     optind++;
 635                 } else {
 636                     arginfo->handle_opt(NULL);
 637                 }
 638                 break;
 639             }
 640         }
 641
 642         /* no option matched the current argv */
 643         if (arginfo->handle_opt == NULL) {
 644             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 645             exit(EXIT_FAILURE);
 646         }
 647     }
 648
 649     if (optind >= argc) {
 650         (void) fprintf(stderr, "qemu: no user program specified\n");
 651         exit(EXIT_FAILURE);
 652     }
 653
 654     exec_path = argv[optind];
 655
 656     return optind;
 657 }
 658
 659 int main(int argc, char **argv, char **envp)
 660 {
 661     struct target_pt_regs regs1, *regs = &regs1;
 662     struct image_info info1, *info = &info1;
 663     struct linux_binprm bprm;
 664     TaskState *ts;
 665     CPUArchState *env;
 666     CPUState *cpu;
 667     int optind;
 668     char **target_environ, **wrk;
 669     char **target_argv;
 670     int target_argc;
 671     int i;
 672     int ret;
 673     int execfd;
 674     unsigned long max_reserved_va;
 675     bool preserve_argv0;
 676
 677     error_init(argv[0]);
 678     module_call_init(MODULE_INIT_TRACE);
 679     qemu_init_cpu_list();
 680     module_call_init(MODULE_INIT_QOM);
 681
 682     envlist = envlist_create();
 683
 684     /* add current environment into the list */
 685     for (wrk = environ; *wrk != NULL; wrk++) {
 686         (void) envlist_setenv(envlist, *wrk);
 687     }
 688
 689     /* Read the stack limit from the kernel.  If it's "unlimited",
 690        then we can do little else besides use the default.  */
 691     {
 692         struct rlimit lim;
 693         if (getrlimit(RLIMIT_STACK, &lim) == 0
 694             && lim.rlim_cur != RLIM_INFINITY
 695             && lim.rlim_cur == (target_long)lim.rlim_cur
 696             && lim.rlim_cur > guest_stack_size) {
 697             guest_stack_size = lim.rlim_cur;
 698         }
 699     }
 700
 701     cpu_model = NULL;
 702
 703     qemu_add_opts(&qemu_trace_opts);
 704     qemu_plugin_add_opts();
 705
 706     optind = parse_args(argc, argv);
 707
 708     qemu_set_log_filename_flags(last_log_filename,
 709                                 last_log_mask | (enable_strace * LOG_STRACE),
 710                                 &error_fatal);
 711
 712     if (!trace_init_backends()) {
 713         exit(1);
 714     }
 715     trace_init_file();
 716     qemu_plugin_load_list(&plugins, &error_fatal);
 717
 718     /* Zero out regs */
 719     memset(regs, 0, sizeof(struct target_pt_regs));
 720
 721     /* Zero out image_info */
 722     memset(info, 0, sizeof(struct image_info));
 723
 724     memset(&bprm, 0, sizeof (bprm));
 725
 726     /* Scan interp_prefix dir for replacement files. */
 727     init_paths(interp_prefix);
 728
 729     init_qemu_uname_release();
 730
 731     /*
 732      * Manage binfmt-misc open-binary flag
 733      */
 734     execfd = qemu_getauxval(AT_EXECFD);
 735     if (execfd == 0) {
 736         execfd = open(exec_path, O_RDONLY);
 737         if (execfd < 0) {
 738             printf("Error while loading %s: %s\n", exec_path, strerror(errno));
 739             _exit(EXIT_FAILURE);
 740         }
 741     }
 742
 743     /*
 744      * get binfmt_misc flags
 745      */
 746     preserve_argv0 = !!(qemu_getauxval(AT_FLAGS) & AT_FLAGS_PRESERVE_ARGV0);
 747
 748     /*
 749      * Manage binfmt-misc preserve-arg[0] flag
 750      *    argv[optind]     full path to the binary
 751      *    argv[optind + 1] original argv[0]
 752      */
 753     if (optind + 1 < argc && preserve_argv0) {
 754         optind++;
 755     }
 756
 757     if (cpu_model == NULL) {
 758         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 759     }
 760     cpu_type = parse_cpu_option(cpu_model);
 761
 762     /* init tcg before creating CPUs and to get qemu_host_page_size */
 763     {
 764         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 765
 766         accel_init_interfaces(ac);
 767         ac->init_machine(NULL);
 768     }
 769     cpu = cpu_create(cpu_type);
 770     env = cpu->env_ptr;
 771     cpu_reset(cpu);
 772     thread_cpu = cpu;
 773
 774     /*
 775      * Reserving too much vm space via mmap can run into problems
 776      * with rlimits, oom due to page table creation, etc.  We will
 777      * still try it, if directed by the command-line option, but
 778      * not by default.
 779      */
 780     max_reserved_va = MAX_RESERVED_VA(cpu);
 781     if (reserved_va != 0) {
 782         if (max_reserved_va && reserved_va > max_reserved_va) {
 783             fprintf(stderr, "Reserved virtual address too big\n");
 784             exit(EXIT_FAILURE);
 785         }
 786     } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
 787         /*
 788          * reserved_va must be aligned with the host page size
 789          * as it is used with mmap()
 790          */
 791         reserved_va = max_reserved_va & qemu_host_page_mask;
 792     }
 793
 794     {
 795         Error *err = NULL;
 796         if (seed_optarg != NULL) {
 797             qemu_guest_random_seed_main(seed_optarg, &err);
 798         } else {
 799             qcrypto_init(&err);
 800         }
 801         if (err) {
 802             error_reportf_err(err, "cannot initialize crypto: ");
 803             exit(1);
 804         }
 805     }
 806
 807     target_environ = envlist_to_environ(envlist, NULL);
 808     envlist_free(envlist);
 809
 810     /*
 811      * Read in mmap_min_addr kernel parameter.  This value is used
 812      * When loading the ELF image to determine whether guest_base
 813      * is needed.  It is also used in mmap_find_vma.
 814      */
 815     {
 816         FILE *fp;
 817
 818         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 819             unsigned long tmp;
 820             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
 821                 mmap_min_addr = tmp;
 822                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
 823                               mmap_min_addr);
 824             }
 825             fclose(fp);
 826         }
 827     }
 828
 829     /*
 830      * We prefer to not make NULL pointers accessible to QEMU.
 831      * If we're in a chroot with no /proc, fall back to 1 page.
 832      */
 833     if (mmap_min_addr == 0) {
 834         mmap_min_addr = qemu_host_page_size;
 835         qemu_log_mask(CPU_LOG_PAGE,
 836                       "host mmap_min_addr=0x%lx (fallback)\n",
 837                       mmap_min_addr);
 838     }
 839
 840     /*
 841      * Prepare copy of argv vector for target.
 842      */
 843     target_argc = argc - optind;
 844     target_argv = calloc(target_argc + 1, sizeof (char *));
 845     if (target_argv == NULL) {
 846         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 847         exit(EXIT_FAILURE);
 848     }
 849
 850     /*
 851      * If argv0 is specified (using '-0' switch) we replace
 852      * argv[0] pointer with the given one.
 853      */
 854     i = 0;
 855     if (argv0 != NULL) {
 856         target_argv[i++] = strdup(argv0);
 857     }
 858     for (; i < target_argc; i++) {
 859         target_argv[i] = strdup(argv[optind + i]);
 860     }
 861     target_argv[target_argc] = NULL;
 862
 863     ts = g_new0(TaskState, 1);
 864     init_task_state(ts);
 865     /* build Task State */
 866     ts->info = info;
 867     ts->bprm = &bprm;
 868     cpu->opaque = ts;
 869     task_settid(ts);
 870
 871     fd_trans_init();
 872
 873     ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
 874         info, &bprm);
 875     if (ret != 0) {
 876         printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
 877         _exit(EXIT_FAILURE);
 878     }
 879
 880     for (wrk = target_environ; *wrk; wrk++) {
 881         g_free(*wrk);
 882     }
 883
 884     g_free(target_environ);
 885
 886     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 887         FILE *f = qemu_log_trylock();
 888         if (f) {
 889             fprintf(f, "guest_base  %p\n", (void *)guest_base);
 890             fprintf(f, "page layout changed following binary load\n");
 891             page_dump(f);
 892
 893             fprintf(f, "start_brk   0x" TARGET_ABI_FMT_lx "\n",
 894                     info->start_brk);
 895             fprintf(f, "end_code    0x" TARGET_ABI_FMT_lx "\n",
 896                     info->end_code);
 897             fprintf(f, "start_code  0x" TARGET_ABI_FMT_lx "\n",
 898                     info->start_code);
 899             fprintf(f, "start_data  0x" TARGET_ABI_FMT_lx "\n",
 900                     info->start_data);
 901             fprintf(f, "end_data    0x" TARGET_ABI_FMT_lx "\n",
 902                     info->end_data);
 903             fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n",
 904                     info->start_stack);
 905             fprintf(f, "brk         0x" TARGET_ABI_FMT_lx "\n",
 906                     info->brk);
 907             fprintf(f, "entry       0x" TARGET_ABI_FMT_lx "\n",
 908                     info->entry);
 909             fprintf(f, "argv_start  0x" TARGET_ABI_FMT_lx "\n",
 910                     info->argv);
 911             fprintf(f, "env_start   0x" TARGET_ABI_FMT_lx "\n",
 912                     info->envp);
 913             fprintf(f, "auxv_start  0x" TARGET_ABI_FMT_lx "\n",
 914                     info->saved_auxv);
 915             qemu_log_unlock(f);
 916         }
 917     }
 918
 919     target_set_brk(info->brk);
 920     syscall_init();
 921     signal_init();
 922
 923     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 924        generating the prologue until now so that the prologue can take
 925        the real value of GUEST_BASE into account.  */
 926     tcg_prologue_init(tcg_ctx);
 927
 928     target_cpu_copy_regs(env, regs);
 929
 930     if (gdbstub) {
 931         if (gdbserver_start(gdbstub) < 0) {
 932             fprintf(stderr, "qemu: could not open gdbserver on %s\n",
 933                     gdbstub);
 934             exit(EXIT_FAILURE);
 935         }
 936         gdb_handlesig(cpu, 0);
 937     }
 938
 939 #ifdef CONFIG_SEMIHOSTING
 940     qemu_semihosting_guestfd_init();
 941 #endif
 942
 943     cpu_loop(env);
 944     /* never exits */
 945     return 0;
 946 }