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