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