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 "sysemu/tcg.h"
  25 #include "qemu-version.h"
  26 #include <sys/syscall.h>
  27 #include <sys/resource.h>
  28 #include <sys/shm.h>
  29 #include <linux/binfmts.h>
  30
  31 #include "qapi/error.h"
  32 #include "qemu.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 "tcg/tcg.h"
  43 #include "qemu/timer.h"
  44 #include "qemu/envlist.h"
  45 #include "qemu/guest-random.h"
  46 #include "elf.h"
  47 #include "trace/control.h"
  48 #include "target_elf.h"
  49 #include "cpu_loop-common.h"
  50 #include "crypto/init.h"
  51
  52 #ifndef AT_FLAGS_PRESERVE_ARGV0
  53 #define AT_FLAGS_PRESERVE_ARGV0_BIT 0
  54 #define AT_FLAGS_PRESERVE_ARGV0 (1 << AT_FLAGS_PRESERVE_ARGV0_BIT)
  55 #endif
  56
  57 char *exec_path;
  58
  59 int singlestep;
  60 static const char *argv0;
  61 static const char *gdbstub;
  62 static envlist_t *envlist;
  63 static const char *cpu_model;
  64 static const char *cpu_type;
  65 static const char *seed_optarg;
  66 unsigned long mmap_min_addr;
  67 uintptr_t guest_base;
  68 bool have_guest_base;
  69
  70 /*
  71  * Used to implement backwards-compatibility for the `-strace`, and
  72  * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by
  73  * -strace, or vice versa.
  74  */
  75 static bool enable_strace;
  76
  77 /*
  78  * The last log mask given by the user in an environment variable or argument.
  79  * Used to support command line arguments overriding environment variables.
  80  */
  81 static int last_log_mask;
  82
  83 /*
  84  * When running 32-on-64 we should make sure we can fit all of the possible
  85  * guest address space into a contiguous chunk of virtual host memory.
  86  *
  87  * This way we will never overlap with our own libraries or binaries or stack
  88  * or anything else that QEMU maps.
  89  *
  90  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  91  * of the address for the kernel.  Some cpus rely on this and user space
  92  * uses the high bit(s) for pointer tagging and the like.  For them, we
  93  * must preserve the expected address space.
  94  */
  95 #ifndef MAX_RESERVED_VA
  96 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
  97 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
  98       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
  99 /* There are a number of places where we assign reserved_va to a variable
 100    of type abi_ulong and expect it to fit.  Avoid the last page.  */
 101 #   define MAX_RESERVED_VA(CPU)  (0xfffffffful & TARGET_PAGE_MASK)
 102 #  else
 103 #   define MAX_RESERVED_VA(CPU)  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
 104 #  endif
 105 # else
 106 #  define MAX_RESERVED_VA(CPU)  0
 107 # endif
 108 #endif
 109
 110 unsigned long reserved_va;
 111
 112 static void usage(int exitcode);
 113
 114 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
 115 const char *qemu_uname_release;
 116
 117 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
 118    we allocate a bigger stack. Need a better solution, for example
 119    by remapping the process stack directly at the right place */
 120 unsigned long guest_stack_size = 8 * 1024 * 1024UL;
 121
 122 #if defined(TARGET_I386)
 123 int cpu_get_pic_interrupt(CPUX86State *env)
 124 {
 125     return -1;
 126 }
 127 #endif
 128
 129 /***********************************************************/
 130 /* Helper routines for implementing atomic operations.  */
 131
 132 /* Make sure everything is in a consistent state for calling fork().  */
 133 void fork_start(void)
 134 {
 135     start_exclusive();
 136     mmap_fork_start();
 137     cpu_list_lock();
 138 }
 139
 140 void fork_end(int child)
 141 {
 142     mmap_fork_end(child);
 143     if (child) {
 144         CPUState *cpu, *next_cpu;
 145         /* Child processes created by fork() only have a single thread.
 146            Discard information about the parent threads.  */
 147         CPU_FOREACH_SAFE(cpu, next_cpu) {
 148             if (cpu != thread_cpu) {
 149                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 150             }
 151         }
 152         qemu_init_cpu_list();
 153         gdbserver_fork(thread_cpu);
 154         /* qemu_init_cpu_list() takes care of reinitializing the
 155          * exclusive state, so we don't need to end_exclusive() here.
 156          */
 157     } else {
 158         cpu_list_unlock();
 159         end_exclusive();
 160     }
 161 }
 162
 163 __thread CPUState *thread_cpu;
 164
 165 bool qemu_cpu_is_self(CPUState *cpu)
 166 {
 167     return thread_cpu == cpu;
 168 }
 169
 170 void qemu_cpu_kick(CPUState *cpu)
 171 {
 172     cpu_exit(cpu);
 173 }
 174
 175 void task_settid(TaskState *ts)
 176 {
 177     if (ts->ts_tid == 0) {
 178         ts->ts_tid = (pid_t)syscall(SYS_gettid);
 179     }
 180 }
 181
 182 void stop_all_tasks(void)
 183 {
 184     /*
 185      * We trust that when using NPTL, start_exclusive()
 186      * handles thread stopping correctly.
 187      */
 188     start_exclusive();
 189 }
 190
 191 /* Assumes contents are already zeroed.  */
 192 void init_task_state(TaskState *ts)
 193 {
 194     ts->used = 1;
 195     ts->sigaltstack_used = (struct target_sigaltstack) {
 196         .ss_sp = 0,
 197         .ss_size = 0,
 198         .ss_flags = TARGET_SS_DISABLE,
 199     };
 200 }
 201
 202 CPUArchState *cpu_copy(CPUArchState *env)
 203 {
 204     CPUState *cpu = env_cpu(env);
 205     CPUState *new_cpu = cpu_create(cpu_type);
 206     CPUArchState *new_env = new_cpu->env_ptr;
 207     CPUBreakpoint *bp;
 208     CPUWatchpoint *wp;
 209
 210     /* Reset non arch specific state */
 211     cpu_reset(new_cpu);
 212
 213     new_cpu->tcg_cflags = cpu->tcg_cflags;
 214     memcpy(new_env, env, sizeof(CPUArchState));
 215
 216     /* Clone all break/watchpoints.
 217        Note: Once we support ptrace with hw-debug register access, make sure
 218        BP_CPU break/watchpoints are handled correctly on clone. */
 219     QTAILQ_INIT(&new_cpu->breakpoints);
 220     QTAILQ_INIT(&new_cpu->watchpoints);
 221     QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
 222         cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
 223     }
 224     QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
 225         cpu_watchpoint_insert(new_cpu, wp->vaddr, wp->len, wp->flags, NULL);
 226     }
 227
 228     return new_env;
 229 }
 230
 231 static void handle_arg_help(const char *arg)
 232 {
 233     usage(EXIT_SUCCESS);
 234 }
 235
 236 static void handle_arg_log(const char *arg)
 237 {
 238     last_log_mask = qemu_str_to_log_mask(arg);
 239     if (!last_log_mask) {
 240         qemu_print_log_usage(stdout);
 241         exit(EXIT_FAILURE);
 242     }
 243 }
 244
 245 static void handle_arg_dfilter(const char *arg)
 246 {
 247     qemu_set_dfilter_ranges(arg, &error_fatal);
 248 }
 249
 250 static void handle_arg_log_filename(const char *arg)
 251 {
 252     qemu_set_log_filename(arg, &error_fatal);
 253 }
 254
 255 static void handle_arg_set_env(const char *arg)
 256 {
 257     char *r, *p, *token;
 258     r = p = strdup(arg);
 259     while ((token = strsep(&p, ",")) != NULL) {
 260         if (envlist_setenv(envlist, token) != 0) {
 261             usage(EXIT_FAILURE);
 262         }
 263     }
 264     free(r);
 265 }
 266
 267 static void handle_arg_unset_env(const char *arg)
 268 {
 269     char *r, *p, *token;
 270     r = p = strdup(arg);
 271     while ((token = strsep(&p, ",")) != NULL) {
 272         if (envlist_unsetenv(envlist, token) != 0) {
 273             usage(EXIT_FAILURE);
 274         }
 275     }
 276     free(r);
 277 }
 278
 279 static void handle_arg_argv0(const char *arg)
 280 {
 281     argv0 = strdup(arg);
 282 }
 283
 284 static void handle_arg_stack_size(const char *arg)
 285 {
 286     char *p;
 287     guest_stack_size = strtoul(arg, &p, 0);
 288     if (guest_stack_size == 0) {
 289         usage(EXIT_FAILURE);
 290     }
 291
 292     if (*p == 'M') {
 293         guest_stack_size *= MiB;
 294     } else if (*p == 'k' || *p == 'K') {
 295         guest_stack_size *= KiB;
 296     }
 297 }
 298
 299 static void handle_arg_ld_prefix(const char *arg)
 300 {
 301     interp_prefix = strdup(arg);
 302 }
 303
 304 static void handle_arg_pagesize(const char *arg)
 305 {
 306     qemu_host_page_size = atoi(arg);
 307     if (qemu_host_page_size == 0 ||
 308         (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 309         fprintf(stderr, "page size must be a power of two\n");
 310         exit(EXIT_FAILURE);
 311     }
 312 }
 313
 314 static void handle_arg_seed(const char *arg)
 315 {
 316     seed_optarg = arg;
 317 }
 318
 319 static void handle_arg_gdb(const char *arg)
 320 {
 321     gdbstub = g_strdup(arg);
 322 }
 323
 324 static void handle_arg_uname(const char *arg)
 325 {
 326     qemu_uname_release = strdup(arg);
 327 }
 328
 329 static void handle_arg_cpu(const char *arg)
 330 {
 331     cpu_model = strdup(arg);
 332     if (cpu_model == NULL || is_help_option(cpu_model)) {
 333         /* XXX: implement xxx_cpu_list for targets that still miss it */
 334 #if defined(cpu_list)
 335         cpu_list();
 336 #endif
 337         exit(EXIT_FAILURE);
 338     }
 339 }
 340
 341 static void handle_arg_guest_base(const char *arg)
 342 {
 343     guest_base = strtol(arg, NULL, 0);
 344     have_guest_base = true;
 345 }
 346
 347 static void handle_arg_reserved_va(const char *arg)
 348 {
 349     char *p;
 350     int shift = 0;
 351     reserved_va = strtoul(arg, &p, 0);
 352     switch (*p) {
 353     case 'k':
 354     case 'K':
 355         shift = 10;
 356         break;
 357     case 'M':
 358         shift = 20;
 359         break;
 360     case 'G':
 361         shift = 30;
 362         break;
 363     }
 364     if (shift) {
 365         unsigned long unshifted = reserved_va;
 366         p++;
 367         reserved_va <<= shift;
 368         if (reserved_va >> shift != unshifted) {
 369             fprintf(stderr, "Reserved virtual address too big\n");
 370             exit(EXIT_FAILURE);
 371         }
 372     }
 373     if (*p) {
 374         fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
 375         exit(EXIT_FAILURE);
 376     }
 377 }
 378
 379 static void handle_arg_singlestep(const char *arg)
 380 {
 381     singlestep = 1;
 382 }
 383
 384 static void handle_arg_strace(const char *arg)
 385 {
 386     enable_strace = true;
 387 }
 388
 389 static void handle_arg_version(const char *arg)
 390 {
 391     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 392            "\n" QEMU_COPYRIGHT "\n");
 393     exit(EXIT_SUCCESS);
 394 }
 395
 396 static void handle_arg_trace(const char *arg)
 397 {
 398     trace_opt_parse(arg);
 399 }
 400
 401 #if defined(TARGET_XTENSA)
 402 static void handle_arg_abi_call0(const char *arg)
 403 {
 404     xtensa_set_abi_call0();
 405 }
 406 #endif
 407
 408 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
 409
 410 #ifdef CONFIG_PLUGIN
 411 static void handle_arg_plugin(const char *arg)
 412 {
 413     qemu_plugin_opt_parse(arg, &plugins);
 414 }
 415 #endif
 416
 417 struct qemu_argument {
 418     const char *argv;
 419     const char *env;
 420     bool has_arg;
 421     void (*handle_opt)(const char *arg);
 422     const char *example;
 423     const char *help;
 424 };
 425
 426 static const struct qemu_argument arg_table[] = {
 427     {"h",          "",                 false, handle_arg_help,
 428      "",           "print this help"},
 429     {"help",       "",                 false, handle_arg_help,
 430      "",           ""},
 431     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 432      "port",       "wait gdb connection to 'port'"},
 433     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 434      "path",       "set the elf interpreter prefix to 'path'"},
 435     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 436      "size",       "set the stack size to 'size' bytes"},
 437     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 438      "model",      "select CPU (-cpu help for list)"},
 439     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 440      "var=value",  "sets targets environment variable (see below)"},
 441     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 442      "var",        "unsets targets environment variable (see below)"},
 443     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 444      "argv0",      "forces target process argv[0] to be 'argv0'"},
 445     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 446      "uname",      "set qemu uname release string to 'uname'"},
 447     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 448      "address",    "set guest_base address to 'address'"},
 449     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 450      "size",       "reserve 'size' bytes for guest virtual address space"},
 451     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 452      "item[,...]", "enable logging of specified items "
 453      "(use '-d help' for a list of items)"},
 454     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 455      "range[,...]","filter logging based on address range"},
 456     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 457      "logfile",     "write logs to 'logfile' (default stderr)"},
 458     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 459      "pagesize",   "set the host page size to 'pagesize'"},
 460     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 461      "",           "run in singlestep mode"},
 462     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 463      "",           "log system calls"},
 464     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_seed,
 465      "",           "Seed for pseudo-random number generator"},
 466     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 467      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 468 #ifdef CONFIG_PLUGIN
 469     {"plugin",     "QEMU_PLUGIN",      true,  handle_arg_plugin,
 470      "",           "[file=]<file>[,arg=<string>]"},
 471 #endif
 472     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 473      "",           "display version information and exit"},
 474 #if defined(TARGET_XTENSA)
 475     {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
 476      "",           "assume CALL0 Xtensa ABI"},
 477 #endif
 478     {NULL, NULL, false, NULL, NULL, NULL}
 479 };
 480
 481 static void usage(int exitcode)
 482 {
 483     const struct qemu_argument *arginfo;
 484     int maxarglen;
 485     int maxenvlen;
 486
 487     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 488            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 489            "\n"
 490            "Options and associated environment variables:\n"
 491            "\n");
 492
 493     /* Calculate column widths. We must always have at least enough space
 494      * for the column header.
 495      */
 496     maxarglen = strlen("Argument");
 497     maxenvlen = strlen("Env-variable");
 498
 499     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 500         int arglen = strlen(arginfo->argv);
 501         if (arginfo->has_arg) {
 502             arglen += strlen(arginfo->example) + 1;
 503         }
 504         if (strlen(arginfo->env) > maxenvlen) {
 505             maxenvlen = strlen(arginfo->env);
 506         }
 507         if (arglen > maxarglen) {
 508             maxarglen = arglen;
 509         }
 510     }
 511
 512     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 513             maxenvlen, "Env-variable");
 514
 515     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 516         if (arginfo->has_arg) {
 517             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 518                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 519                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 520         } else {
 521             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 522                     maxenvlen, arginfo->env,
 523                     arginfo->help);
 524         }
 525     }
 526
 527     printf("\n"
 528            "Defaults:\n"
 529            "QEMU_LD_PREFIX  = %s\n"
 530            "QEMU_STACK_SIZE = %ld byte\n",
 531            interp_prefix,
 532            guest_stack_size);
 533
 534     printf("\n"
 535            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 536            "QEMU_UNSET_ENV environment variables to set and unset\n"
 537            "environment variables for the target process.\n"
 538            "It is possible to provide several variables by separating them\n"
 539            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 540            "provide the -E and -U options multiple times.\n"
 541            "The following lines are equivalent:\n"
 542            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 543            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 544            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 545            "Note that if you provide several changes to a single variable\n"
 546            "the last change will stay in effect.\n"
 547            "\n"
 548            QEMU_HELP_BOTTOM "\n");
 549
 550     exit(exitcode);
 551 }
 552
 553 static int parse_args(int argc, char **argv)
 554 {
 555     const char *r;
 556     int optind;
 557     const struct qemu_argument *arginfo;
 558
 559     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 560         if (arginfo->env == NULL) {
 561             continue;
 562         }
 563
 564         r = getenv(arginfo->env);
 565         if (r != NULL) {
 566             arginfo->handle_opt(r);
 567         }
 568     }
 569
 570     optind = 1;
 571     for (;;) {
 572         if (optind >= argc) {
 573             break;
 574         }
 575         r = argv[optind];
 576         if (r[0] != '-') {
 577             break;
 578         }
 579         optind++;
 580         r++;
 581         if (!strcmp(r, "-")) {
 582             break;
 583         }
 584         /* Treat --foo the same as -foo.  */
 585         if (r[0] == '-') {
 586             r++;
 587         }
 588
 589         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 590             if (!strcmp(r, arginfo->argv)) {
 591                 if (arginfo->has_arg) {
 592                     if (optind >= argc) {
 593                         (void) fprintf(stderr,
 594                             "qemu: missing argument for option '%s'\n", r);
 595                         exit(EXIT_FAILURE);
 596                     }
 597                     arginfo->handle_opt(argv[optind]);
 598                     optind++;
 599                 } else {
 600                     arginfo->handle_opt(NULL);
 601                 }
 602                 break;
 603             }
 604         }
 605
 606         /* no option matched the current argv */
 607         if (arginfo->handle_opt == NULL) {
 608             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 609             exit(EXIT_FAILURE);
 610         }
 611     }
 612
 613     if (optind >= argc) {
 614         (void) fprintf(stderr, "qemu: no user program specified\n");
 615         exit(EXIT_FAILURE);
 616     }
 617
 618     exec_path = argv[optind];
 619
 620     return optind;
 621 }
 622
 623 int main(int argc, char **argv, char **envp)
 624 {
 625     struct target_pt_regs regs1, *regs = &regs1;
 626     struct image_info info1, *info = &info1;
 627     struct linux_binprm bprm;
 628     TaskState *ts;
 629     CPUArchState *env;
 630     CPUState *cpu;
 631     int optind;
 632     char **target_environ, **wrk;
 633     char **target_argv;
 634     int target_argc;
 635     int i;
 636     int ret;
 637     int execfd;
 638     int log_mask;
 639     unsigned long max_reserved_va;
 640     bool preserve_argv0;
 641
 642     error_init(argv[0]);
 643     module_call_init(MODULE_INIT_TRACE);
 644     qemu_init_cpu_list();
 645     module_call_init(MODULE_INIT_QOM);
 646
 647     envlist = envlist_create();
 648
 649     /* add current environment into the list */
 650     for (wrk = environ; *wrk != NULL; wrk++) {
 651         (void) envlist_setenv(envlist, *wrk);
 652     }
 653
 654     /* Read the stack limit from the kernel.  If it's "unlimited",
 655        then we can do little else besides use the default.  */
 656     {
 657         struct rlimit lim;
 658         if (getrlimit(RLIMIT_STACK, &lim) == 0
 659             && lim.rlim_cur != RLIM_INFINITY
 660             && lim.rlim_cur == (target_long)lim.rlim_cur) {
 661             guest_stack_size = lim.rlim_cur;
 662         }
 663     }
 664
 665     cpu_model = NULL;
 666
 667     qemu_add_opts(&qemu_trace_opts);
 668     qemu_plugin_add_opts();
 669
 670     optind = parse_args(argc, argv);
 671
 672     log_mask = last_log_mask | (enable_strace ? LOG_STRACE : 0);
 673     if (log_mask) {
 674         qemu_log_needs_buffers();
 675         qemu_set_log(log_mask);
 676     }
 677
 678     if (!trace_init_backends()) {
 679         exit(1);
 680     }
 681     trace_init_file();
 682     qemu_plugin_load_list(&plugins, &error_fatal);
 683
 684     /* Zero out regs */
 685     memset(regs, 0, sizeof(struct target_pt_regs));
 686
 687     /* Zero out image_info */
 688     memset(info, 0, sizeof(struct image_info));
 689
 690     memset(&bprm, 0, sizeof (bprm));
 691
 692     /* Scan interp_prefix dir for replacement files. */
 693     init_paths(interp_prefix);
 694
 695     init_qemu_uname_release();
 696
 697     /*
 698      * Manage binfmt-misc open-binary flag
 699      */
 700     execfd = qemu_getauxval(AT_EXECFD);
 701     if (execfd == 0) {
 702         execfd = open(exec_path, O_RDONLY);
 703         if (execfd < 0) {
 704             printf("Error while loading %s: %s\n", exec_path, strerror(errno));
 705             _exit(EXIT_FAILURE);
 706         }
 707     }
 708
 709     /*
 710      * get binfmt_misc flags
 711      */
 712     preserve_argv0 = !!(qemu_getauxval(AT_FLAGS) & AT_FLAGS_PRESERVE_ARGV0);
 713
 714     /*
 715      * Manage binfmt-misc preserve-arg[0] flag
 716      *    argv[optind]     full path to the binary
 717      *    argv[optind + 1] original argv[0]
 718      */
 719     if (optind + 1 < argc && preserve_argv0) {
 720         optind++;
 721     }
 722
 723     if (cpu_model == NULL) {
 724         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 725     }
 726     cpu_type = parse_cpu_option(cpu_model);
 727
 728     /* init tcg before creating CPUs and to get qemu_host_page_size */
 729     {
 730         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 731
 732         ac->init_machine(NULL);
 733         accel_init_interfaces(ac);
 734     }
 735     cpu = cpu_create(cpu_type);
 736     env = cpu->env_ptr;
 737     cpu_reset(cpu);
 738     thread_cpu = cpu;
 739
 740     /*
 741      * Reserving too much vm space via mmap can run into problems
 742      * with rlimits, oom due to page table creation, etc.  We will
 743      * still try it, if directed by the command-line option, but
 744      * not by default.
 745      */
 746     max_reserved_va = MAX_RESERVED_VA(cpu);
 747     if (reserved_va != 0) {
 748         if (max_reserved_va && reserved_va > max_reserved_va) {
 749             fprintf(stderr, "Reserved virtual address too big\n");
 750             exit(EXIT_FAILURE);
 751         }
 752     } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
 753         /*
 754          * reserved_va must be aligned with the host page size
 755          * as it is used with mmap()
 756          */
 757         reserved_va = max_reserved_va & qemu_host_page_mask;
 758     }
 759
 760     {
 761         Error *err = NULL;
 762         if (seed_optarg != NULL) {
 763             qemu_guest_random_seed_main(seed_optarg, &err);
 764         } else {
 765             qcrypto_init(&err);
 766         }
 767         if (err) {
 768             error_reportf_err(err, "cannot initialize crypto: ");
 769             exit(1);
 770         }
 771     }
 772
 773     target_environ = envlist_to_environ(envlist, NULL);
 774     envlist_free(envlist);
 775
 776     /*
 777      * Read in mmap_min_addr kernel parameter.  This value is used
 778      * When loading the ELF image to determine whether guest_base
 779      * is needed.  It is also used in mmap_find_vma.
 780      */
 781     {
 782         FILE *fp;
 783
 784         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 785             unsigned long tmp;
 786             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
 787                 mmap_min_addr = tmp;
 788                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
 789                               mmap_min_addr);
 790             }
 791             fclose(fp);
 792         }
 793     }
 794
 795     /*
 796      * We prefer to not make NULL pointers accessible to QEMU.
 797      * If we're in a chroot with no /proc, fall back to 1 page.
 798      */
 799     if (mmap_min_addr == 0) {
 800         mmap_min_addr = qemu_host_page_size;
 801         qemu_log_mask(CPU_LOG_PAGE,
 802                       "host mmap_min_addr=0x%lx (fallback)\n",
 803                       mmap_min_addr);
 804     }
 805
 806     /*
 807      * Prepare copy of argv vector for target.
 808      */
 809     target_argc = argc - optind;
 810     target_argv = calloc(target_argc + 1, sizeof (char *));
 811     if (target_argv == NULL) {
 812         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 813         exit(EXIT_FAILURE);
 814     }
 815
 816     /*
 817      * If argv0 is specified (using '-0' switch) we replace
 818      * argv[0] pointer with the given one.
 819      */
 820     i = 0;
 821     if (argv0 != NULL) {
 822         target_argv[i++] = strdup(argv0);
 823     }
 824     for (; i < target_argc; i++) {
 825         target_argv[i] = strdup(argv[optind + i]);
 826     }
 827     target_argv[target_argc] = NULL;
 828
 829     ts = g_new0(TaskState, 1);
 830     init_task_state(ts);
 831     /* build Task State */
 832     ts->info = info;
 833     ts->bprm = &bprm;
 834     cpu->opaque = ts;
 835     task_settid(ts);
 836
 837     ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
 838         info, &bprm);
 839     if (ret != 0) {
 840         printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
 841         _exit(EXIT_FAILURE);
 842     }
 843
 844     for (wrk = target_environ; *wrk; wrk++) {
 845         g_free(*wrk);
 846     }
 847
 848     g_free(target_environ);
 849
 850     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 851         qemu_log("guest_base  %p\n", (void *)guest_base);
 852         log_page_dump("binary load");
 853
 854         qemu_log("start_brk   0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
 855         qemu_log("end_code    0x" TARGET_ABI_FMT_lx "\n", info->end_code);
 856         qemu_log("start_code  0x" TARGET_ABI_FMT_lx "\n", info->start_code);
 857         qemu_log("start_data  0x" TARGET_ABI_FMT_lx "\n", info->start_data);
 858         qemu_log("end_data    0x" TARGET_ABI_FMT_lx "\n", info->end_data);
 859         qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n", info->start_stack);
 860         qemu_log("brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 861         qemu_log("entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 862         qemu_log("argv_start  0x" TARGET_ABI_FMT_lx "\n", info->arg_start);
 863         qemu_log("env_start   0x" TARGET_ABI_FMT_lx "\n",
 864                  info->arg_end + (abi_ulong)sizeof(abi_ulong));
 865         qemu_log("auxv_start  0x" TARGET_ABI_FMT_lx "\n", info->saved_auxv);
 866     }
 867
 868     target_set_brk(info->brk);
 869     syscall_init();
 870     signal_init();
 871
 872     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 873        generating the prologue until now so that the prologue can take
 874        the real value of GUEST_BASE into account.  */
 875     tcg_prologue_init(tcg_ctx);
 876     tcg_region_init();
 877
 878     target_cpu_copy_regs(env, regs);
 879
 880     if (gdbstub) {
 881         if (gdbserver_start(gdbstub) < 0) {
 882             fprintf(stderr, "qemu: could not open gdbserver on %s\n",
 883                     gdbstub);
 884             exit(EXIT_FAILURE);
 885         }
 886         gdb_handlesig(cpu, 0);
 887     }
 888     cpu_loop(env);
 889     /* never exits */
 890     return 0;
 891 }