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