1 /* 2 * qemu user main 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "qemu/help-texts.h" 22 #include "qemu/units.h" 23 #include "qemu/accel.h" 24 #include "qemu-version.h" 25 #include <sys/syscall.h> 26 #include <sys/resource.h> 27 #include <sys/shm.h> 28 #include <linux/binfmts.h> 29 30 #include "qapi/error.h" 31 #include "qemu.h" 32 #include "user-internals.h" 33 #include "qemu/path.h" 34 #include "qemu/queue.h" 35 #include "qemu/config-file.h" 36 #include "qemu/cutils.h" 37 #include "qemu/error-report.h" 38 #include "qemu/help_option.h" 39 #include "qemu/module.h" 40 #include "qemu/plugin.h" 41 #include "exec/exec-all.h" 42 #include "exec/gdbstub.h" 43 #include "gdbstub/user.h" 44 #include "tcg/tcg.h" 45 #include "qemu/timer.h" 46 #include "qemu/envlist.h" 47 #include "qemu/guest-random.h" 48 #include "elf.h" 49 #include "trace/control.h" 50 #include "target_elf.h" 51 #include "cpu_loop-common.h" 52 #include "crypto/init.h" 53 #include "fd-trans.h" 54 #include "signal-common.h" 55 #include "loader.h" 56 #include "user-mmap.h" 57 #include "accel/tcg/perf.h" 58 59 #ifdef CONFIG_SEMIHOSTING 60 #include "semihosting/semihost.h" 61 #endif 62 63 #ifndef AT_FLAGS_PRESERVE_ARGV0 64 #define AT_FLAGS_PRESERVE_ARGV0_BIT 0 65 #define AT_FLAGS_PRESERVE_ARGV0 (1 << AT_FLAGS_PRESERVE_ARGV0_BIT) 66 #endif 67 68 char *exec_path; 69 char real_exec_path[PATH_MAX]; 70 71 static bool opt_one_insn_per_tb; 72 static const char *argv0; 73 static const char *gdbstub; 74 static envlist_t *envlist; 75 static const char *cpu_model; 76 static const char *cpu_type; 77 static const char *seed_optarg; 78 unsigned long mmap_min_addr; 79 uintptr_t guest_base; 80 bool have_guest_base; 81 82 /* 83 * Used to implement backwards-compatibility for the `-strace`, and 84 * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by 85 * -strace, or vice versa. 86 */ 87 static bool enable_strace; 88 89 /* 90 * The last log mask given by the user in an environment variable or argument. 91 * Used to support command line arguments overriding environment variables. 92 */ 93 static int last_log_mask; 94 static const char *last_log_filename; 95 96 /* 97 * When running 32-on-64 we should make sure we can fit all of the possible 98 * guest address space into a contiguous chunk of virtual host memory. 99 * 100 * This way we will never overlap with our own libraries or binaries or stack 101 * or anything else that QEMU maps. 102 * 103 * Many cpus reserve the high bit (or more than one for some 64-bit cpus) 104 * of the address for the kernel. Some cpus rely on this and user space 105 * uses the high bit(s) for pointer tagging and the like. For them, we 106 * must preserve the expected address space. 107 */ 108 #ifndef MAX_RESERVED_VA 109 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS 110 # if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \ 111 (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32)) 112 # define MAX_RESERVED_VA(CPU) 0xfffffffful 113 # else 114 # define MAX_RESERVED_VA(CPU) ((1ul << TARGET_VIRT_ADDR_SPACE_BITS) - 1) 115 # endif 116 # else 117 # define MAX_RESERVED_VA(CPU) 0 118 # endif 119 #endif 120 121 unsigned long reserved_va; 122 123 static void usage(int exitcode); 124 125 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX; 126 const char *qemu_uname_release; 127 128 #if !defined(TARGET_DEFAULT_STACK_SIZE) 129 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so 130 we allocate a bigger stack. Need a better solution, for example 131 by remapping the process stack directly at the right place */ 132 #define TARGET_DEFAULT_STACK_SIZE 8 * 1024 * 1024UL 133 #endif 134 135 unsigned long guest_stack_size = TARGET_DEFAULT_STACK_SIZE; 136 137 /***********************************************************/ 138 /* Helper routines for implementing atomic operations. */ 139 140 /* Make sure everything is in a consistent state for calling fork(). */ 141 void fork_start(void) 142 { 143 start_exclusive(); 144 mmap_fork_start(); 145 cpu_list_lock(); 146 qemu_plugin_user_prefork_lock(); 147 } 148 149 void fork_end(int child) 150 { 151 qemu_plugin_user_postfork(child); 152 mmap_fork_end(child); 153 if (child) { 154 CPUState *cpu, *next_cpu; 155 /* Child processes created by fork() only have a single thread. 156 Discard information about the parent threads. */ 157 CPU_FOREACH_SAFE(cpu, next_cpu) { 158 if (cpu != thread_cpu) { 159 QTAILQ_REMOVE_RCU(&cpus, cpu, node); 160 } 161 } 162 qemu_init_cpu_list(); 163 gdbserver_fork(thread_cpu); 164 } else { 165 cpu_list_unlock(); 166 } 167 /* 168 * qemu_init_cpu_list() reinitialized the child exclusive state, but we 169 * also need to keep current_cpu consistent, so call end_exclusive() for 170 * both child and parent. 171 */ 172 end_exclusive(); 173 } 174 175 __thread CPUState *thread_cpu; 176 177 bool qemu_cpu_is_self(CPUState *cpu) 178 { 179 return thread_cpu == cpu; 180 } 181 182 void qemu_cpu_kick(CPUState *cpu) 183 { 184 cpu_exit(cpu); 185 } 186 187 void task_settid(TaskState *ts) 188 { 189 if (ts->ts_tid == 0) { 190 ts->ts_tid = (pid_t)syscall(SYS_gettid); 191 } 192 } 193 194 void stop_all_tasks(void) 195 { 196 /* 197 * We trust that when using NPTL, start_exclusive() 198 * handles thread stopping correctly. 199 */ 200 start_exclusive(); 201 } 202 203 /* Assumes contents are already zeroed. */ 204 void init_task_state(TaskState *ts) 205 { 206 long ticks_per_sec; 207 struct timespec bt; 208 209 ts->used = 1; 210 ts->sigaltstack_used = (struct target_sigaltstack) { 211 .ss_sp = 0, 212 .ss_size = 0, 213 .ss_flags = TARGET_SS_DISABLE, 214 }; 215 216 /* Capture task start time relative to system boot */ 217 218 ticks_per_sec = sysconf(_SC_CLK_TCK); 219 220 if ((ticks_per_sec > 0) && !clock_gettime(CLOCK_BOOTTIME, &bt)) { 221 /* start_boottime is expressed in clock ticks */ 222 ts->start_boottime = bt.tv_sec * (uint64_t) ticks_per_sec; 223 ts->start_boottime += bt.tv_nsec * (uint64_t) ticks_per_sec / 224 NANOSECONDS_PER_SECOND; 225 } 226 } 227 228 CPUArchState *cpu_copy(CPUArchState *env) 229 { 230 CPUState *cpu = env_cpu(env); 231 CPUState *new_cpu = cpu_create(cpu_type); 232 CPUArchState *new_env = new_cpu->env_ptr; 233 CPUBreakpoint *bp; 234 235 /* Reset non arch specific state */ 236 cpu_reset(new_cpu); 237 238 new_cpu->tcg_cflags = cpu->tcg_cflags; 239 memcpy(new_env, env, sizeof(CPUArchState)); 240 #if defined(TARGET_I386) || defined(TARGET_X86_64) 241 new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES, 242 PROT_READ | PROT_WRITE, 243 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); 244 memcpy(g2h_untagged(new_env->gdt.base), g2h_untagged(env->gdt.base), 245 sizeof(uint64_t) * TARGET_GDT_ENTRIES); 246 OBJECT(new_cpu)->free = OBJECT(cpu)->free; 247 #endif 248 249 /* Clone all break/watchpoints. 250 Note: Once we support ptrace with hw-debug register access, make sure 251 BP_CPU break/watchpoints are handled correctly on clone. */ 252 QTAILQ_INIT(&new_cpu->breakpoints); 253 QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) { 254 cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL); 255 } 256 257 return new_env; 258 } 259 260 static void handle_arg_help(const char *arg) 261 { 262 usage(EXIT_SUCCESS); 263 } 264 265 static void handle_arg_log(const char *arg) 266 { 267 last_log_mask = qemu_str_to_log_mask(arg); 268 if (!last_log_mask) { 269 qemu_print_log_usage(stdout); 270 exit(EXIT_FAILURE); 271 } 272 } 273 274 static void handle_arg_dfilter(const char *arg) 275 { 276 qemu_set_dfilter_ranges(arg, &error_fatal); 277 } 278 279 static void handle_arg_log_filename(const char *arg) 280 { 281 last_log_filename = arg; 282 } 283 284 static void handle_arg_set_env(const char *arg) 285 { 286 char *r, *p, *token; 287 r = p = strdup(arg); 288 while ((token = strsep(&p, ",")) != NULL) { 289 if (envlist_setenv(envlist, token) != 0) { 290 usage(EXIT_FAILURE); 291 } 292 } 293 free(r); 294 } 295 296 static void handle_arg_unset_env(const char *arg) 297 { 298 char *r, *p, *token; 299 r = p = strdup(arg); 300 while ((token = strsep(&p, ",")) != NULL) { 301 if (envlist_unsetenv(envlist, token) != 0) { 302 usage(EXIT_FAILURE); 303 } 304 } 305 free(r); 306 } 307 308 static void handle_arg_argv0(const char *arg) 309 { 310 argv0 = strdup(arg); 311 } 312 313 static void handle_arg_stack_size(const char *arg) 314 { 315 char *p; 316 guest_stack_size = strtoul(arg, &p, 0); 317 if (guest_stack_size == 0) { 318 usage(EXIT_FAILURE); 319 } 320 321 if (*p == 'M') { 322 guest_stack_size *= MiB; 323 } else if (*p == 'k' || *p == 'K') { 324 guest_stack_size *= KiB; 325 } 326 } 327 328 static void handle_arg_ld_prefix(const char *arg) 329 { 330 interp_prefix = strdup(arg); 331 } 332 333 static void handle_arg_pagesize(const char *arg) 334 { 335 qemu_host_page_size = atoi(arg); 336 if (qemu_host_page_size == 0 || 337 (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) { 338 fprintf(stderr, "page size must be a power of two\n"); 339 exit(EXIT_FAILURE); 340 } 341 } 342 343 static void handle_arg_seed(const char *arg) 344 { 345 seed_optarg = arg; 346 } 347 348 static void handle_arg_gdb(const char *arg) 349 { 350 gdbstub = g_strdup(arg); 351 } 352 353 static void handle_arg_uname(const char *arg) 354 { 355 qemu_uname_release = strdup(arg); 356 } 357 358 static void handle_arg_cpu(const char *arg) 359 { 360 cpu_model = strdup(arg); 361 if (cpu_model == NULL || is_help_option(cpu_model)) { 362 list_cpus(); 363 exit(EXIT_FAILURE); 364 } 365 } 366 367 static void handle_arg_guest_base(const char *arg) 368 { 369 guest_base = strtol(arg, NULL, 0); 370 have_guest_base = true; 371 } 372 373 static void handle_arg_reserved_va(const char *arg) 374 { 375 char *p; 376 int shift = 0; 377 unsigned long val; 378 379 val = strtoul(arg, &p, 0); 380 switch (*p) { 381 case 'k': 382 case 'K': 383 shift = 10; 384 break; 385 case 'M': 386 shift = 20; 387 break; 388 case 'G': 389 shift = 30; 390 break; 391 } 392 if (shift) { 393 unsigned long unshifted = val; 394 p++; 395 val <<= shift; 396 if (val >> shift != unshifted) { 397 fprintf(stderr, "Reserved virtual address too big\n"); 398 exit(EXIT_FAILURE); 399 } 400 } 401 if (*p) { 402 fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p); 403 exit(EXIT_FAILURE); 404 } 405 /* The representation is size - 1, with 0 remaining "default". */ 406 reserved_va = val ? val - 1 : 0; 407 } 408 409 static void handle_arg_one_insn_per_tb(const char *arg) 410 { 411 opt_one_insn_per_tb = true; 412 } 413 414 static void handle_arg_strace(const char *arg) 415 { 416 enable_strace = true; 417 } 418 419 static void handle_arg_version(const char *arg) 420 { 421 printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION 422 "\n" QEMU_COPYRIGHT "\n"); 423 exit(EXIT_SUCCESS); 424 } 425 426 static void handle_arg_trace(const char *arg) 427 { 428 trace_opt_parse(arg); 429 } 430 431 #if defined(TARGET_XTENSA) 432 static void handle_arg_abi_call0(const char *arg) 433 { 434 xtensa_set_abi_call0(); 435 } 436 #endif 437 438 static void handle_arg_perfmap(const char *arg) 439 { 440 perf_enable_perfmap(); 441 } 442 443 static void handle_arg_jitdump(const char *arg) 444 { 445 perf_enable_jitdump(); 446 } 447 448 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins); 449 450 #ifdef CONFIG_PLUGIN 451 static void handle_arg_plugin(const char *arg) 452 { 453 qemu_plugin_opt_parse(arg, &plugins); 454 } 455 #endif 456 457 struct qemu_argument { 458 const char *argv; 459 const char *env; 460 bool has_arg; 461 void (*handle_opt)(const char *arg); 462 const char *example; 463 const char *help; 464 }; 465 466 static const struct qemu_argument arg_table[] = { 467 {"h", "", false, handle_arg_help, 468 "", "print this help"}, 469 {"help", "", false, handle_arg_help, 470 "", ""}, 471 {"g", "QEMU_GDB", true, handle_arg_gdb, 472 "port", "wait gdb connection to 'port'"}, 473 {"L", "QEMU_LD_PREFIX", true, handle_arg_ld_prefix, 474 "path", "set the elf interpreter prefix to 'path'"}, 475 {"s", "QEMU_STACK_SIZE", true, handle_arg_stack_size, 476 "size", "set the stack size to 'size' bytes"}, 477 {"cpu", "QEMU_CPU", true, handle_arg_cpu, 478 "model", "select CPU (-cpu help for list)"}, 479 {"E", "QEMU_SET_ENV", true, handle_arg_set_env, 480 "var=value", "sets targets environment variable (see below)"}, 481 {"U", "QEMU_UNSET_ENV", true, handle_arg_unset_env, 482 "var", "unsets targets environment variable (see below)"}, 483 {"0", "QEMU_ARGV0", true, handle_arg_argv0, 484 "argv0", "forces target process argv[0] to be 'argv0'"}, 485 {"r", "QEMU_UNAME", true, handle_arg_uname, 486 "uname", "set qemu uname release string to 'uname'"}, 487 {"B", "QEMU_GUEST_BASE", true, handle_arg_guest_base, 488 "address", "set guest_base address to 'address'"}, 489 {"R", "QEMU_RESERVED_VA", true, handle_arg_reserved_va, 490 "size", "reserve 'size' bytes for guest virtual address space"}, 491 {"d", "QEMU_LOG", true, handle_arg_log, 492 "item[,...]", "enable logging of specified items " 493 "(use '-d help' for a list of items)"}, 494 {"dfilter", "QEMU_DFILTER", true, handle_arg_dfilter, 495 "range[,...]","filter logging based on address range"}, 496 {"D", "QEMU_LOG_FILENAME", true, handle_arg_log_filename, 497 "logfile", "write logs to 'logfile' (default stderr)"}, 498 {"p", "QEMU_PAGESIZE", true, handle_arg_pagesize, 499 "pagesize", "set the host page size to 'pagesize'"}, 500 {"one-insn-per-tb", 501 "QEMU_ONE_INSN_PER_TB", false, handle_arg_one_insn_per_tb, 502 "", "run with one guest instruction per emulated TB"}, 503 {"singlestep", "QEMU_SINGLESTEP", false, handle_arg_one_insn_per_tb, 504 "", "deprecated synonym for -one-insn-per-tb"}, 505 {"strace", "QEMU_STRACE", false, handle_arg_strace, 506 "", "log system calls"}, 507 {"seed", "QEMU_RAND_SEED", true, handle_arg_seed, 508 "", "Seed for pseudo-random number generator"}, 509 {"trace", "QEMU_TRACE", true, handle_arg_trace, 510 "", "[[enable=]<pattern>][,events=<file>][,file=<file>]"}, 511 #ifdef CONFIG_PLUGIN 512 {"plugin", "QEMU_PLUGIN", true, handle_arg_plugin, 513 "", "[file=]<file>[,<argname>=<argvalue>]"}, 514 #endif 515 {"version", "QEMU_VERSION", false, handle_arg_version, 516 "", "display version information and exit"}, 517 #if defined(TARGET_XTENSA) 518 {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0, 519 "", "assume CALL0 Xtensa ABI"}, 520 #endif 521 {"perfmap", "QEMU_PERFMAP", false, handle_arg_perfmap, 522 "", "Generate a /tmp/perf-${pid}.map file for perf"}, 523 {"jitdump", "QEMU_JITDUMP", false, handle_arg_jitdump, 524 "", "Generate a jit-${pid}.dump file for perf"}, 525 {NULL, NULL, false, NULL, NULL, NULL} 526 }; 527 528 static void usage(int exitcode) 529 { 530 const struct qemu_argument *arginfo; 531 int maxarglen; 532 int maxenvlen; 533 534 printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n" 535 "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n" 536 "\n" 537 "Options and associated environment variables:\n" 538 "\n"); 539 540 /* Calculate column widths. We must always have at least enough space 541 * for the column header. 542 */ 543 maxarglen = strlen("Argument"); 544 maxenvlen = strlen("Env-variable"); 545 546 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) { 547 int arglen = strlen(arginfo->argv); 548 if (arginfo->has_arg) { 549 arglen += strlen(arginfo->example) + 1; 550 } 551 if (strlen(arginfo->env) > maxenvlen) { 552 maxenvlen = strlen(arginfo->env); 553 } 554 if (arglen > maxarglen) { 555 maxarglen = arglen; 556 } 557 } 558 559 printf("%-*s %-*s Description\n", maxarglen+1, "Argument", 560 maxenvlen, "Env-variable"); 561 562 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) { 563 if (arginfo->has_arg) { 564 printf("-%s %-*s %-*s %s\n", arginfo->argv, 565 (int)(maxarglen - strlen(arginfo->argv) - 1), 566 arginfo->example, maxenvlen, arginfo->env, arginfo->help); 567 } else { 568 printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv, 569 maxenvlen, arginfo->env, 570 arginfo->help); 571 } 572 } 573 574 printf("\n" 575 "Defaults:\n" 576 "QEMU_LD_PREFIX = %s\n" 577 "QEMU_STACK_SIZE = %ld byte\n", 578 interp_prefix, 579 guest_stack_size); 580 581 printf("\n" 582 "You can use -E and -U options or the QEMU_SET_ENV and\n" 583 "QEMU_UNSET_ENV environment variables to set and unset\n" 584 "environment variables for the target process.\n" 585 "It is possible to provide several variables by separating them\n" 586 "by commas in getsubopt(3) style. Additionally it is possible to\n" 587 "provide the -E and -U options multiple times.\n" 588 "The following lines are equivalent:\n" 589 " -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n" 590 " -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n" 591 " QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n" 592 "Note that if you provide several changes to a single variable\n" 593 "the last change will stay in effect.\n" 594 "\n" 595 QEMU_HELP_BOTTOM "\n"); 596 597 exit(exitcode); 598 } 599 600 static int parse_args(int argc, char **argv) 601 { 602 const char *r; 603 int optind; 604 const struct qemu_argument *arginfo; 605 606 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) { 607 if (arginfo->env == NULL) { 608 continue; 609 } 610 611 r = getenv(arginfo->env); 612 if (r != NULL) { 613 arginfo->handle_opt(r); 614 } 615 } 616 617 optind = 1; 618 for (;;) { 619 if (optind >= argc) { 620 break; 621 } 622 r = argv[optind]; 623 if (r[0] != '-') { 624 break; 625 } 626 optind++; 627 r++; 628 if (!strcmp(r, "-")) { 629 break; 630 } 631 /* Treat --foo the same as -foo. */ 632 if (r[0] == '-') { 633 r++; 634 } 635 636 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) { 637 if (!strcmp(r, arginfo->argv)) { 638 if (arginfo->has_arg) { 639 if (optind >= argc) { 640 (void) fprintf(stderr, 641 "qemu: missing argument for option '%s'\n", r); 642 exit(EXIT_FAILURE); 643 } 644 arginfo->handle_opt(argv[optind]); 645 optind++; 646 } else { 647 arginfo->handle_opt(NULL); 648 } 649 break; 650 } 651 } 652 653 /* no option matched the current argv */ 654 if (arginfo->handle_opt == NULL) { 655 (void) fprintf(stderr, "qemu: unknown option '%s'\n", r); 656 exit(EXIT_FAILURE); 657 } 658 } 659 660 if (optind >= argc) { 661 (void) fprintf(stderr, "qemu: no user program specified\n"); 662 exit(EXIT_FAILURE); 663 } 664 665 exec_path = argv[optind]; 666 667 return optind; 668 } 669 670 int main(int argc, char **argv, char **envp) 671 { 672 struct target_pt_regs regs1, *regs = ®s1; 673 struct image_info info1, *info = &info1; 674 struct linux_binprm bprm; 675 TaskState *ts; 676 CPUArchState *env; 677 CPUState *cpu; 678 int optind; 679 char **target_environ, **wrk; 680 char **target_argv; 681 int target_argc; 682 int i; 683 int ret; 684 int execfd; 685 unsigned long max_reserved_va; 686 bool preserve_argv0; 687 688 error_init(argv[0]); 689 module_call_init(MODULE_INIT_TRACE); 690 qemu_init_cpu_list(); 691 module_call_init(MODULE_INIT_QOM); 692 693 envlist = envlist_create(); 694 695 /* 696 * add current environment into the list 697 * envlist_setenv adds to the front of the list; to preserve environ 698 * order add from back to front 699 */ 700 for (wrk = environ; *wrk != NULL; wrk++) { 701 continue; 702 } 703 while (wrk != environ) { 704 wrk--; 705 (void) envlist_setenv(envlist, *wrk); 706 } 707 708 /* Read the stack limit from the kernel. If it's "unlimited", 709 then we can do little else besides use the default. */ 710 { 711 struct rlimit lim; 712 if (getrlimit(RLIMIT_STACK, &lim) == 0 713 && lim.rlim_cur != RLIM_INFINITY 714 && lim.rlim_cur == (target_long)lim.rlim_cur 715 && lim.rlim_cur > guest_stack_size) { 716 guest_stack_size = lim.rlim_cur; 717 } 718 } 719 720 cpu_model = NULL; 721 722 qemu_add_opts(&qemu_trace_opts); 723 qemu_plugin_add_opts(); 724 725 optind = parse_args(argc, argv); 726 727 qemu_set_log_filename_flags(last_log_filename, 728 last_log_mask | (enable_strace * LOG_STRACE), 729 &error_fatal); 730 731 if (!trace_init_backends()) { 732 exit(1); 733 } 734 trace_init_file(); 735 qemu_plugin_load_list(&plugins, &error_fatal); 736 737 /* Zero out regs */ 738 memset(regs, 0, sizeof(struct target_pt_regs)); 739 740 /* Zero out image_info */ 741 memset(info, 0, sizeof(struct image_info)); 742 743 memset(&bprm, 0, sizeof (bprm)); 744 745 /* Scan interp_prefix dir for replacement files. */ 746 init_paths(interp_prefix); 747 748 init_qemu_uname_release(); 749 750 /* 751 * Manage binfmt-misc open-binary flag 752 */ 753 execfd = qemu_getauxval(AT_EXECFD); 754 if (execfd == 0) { 755 execfd = open(exec_path, O_RDONLY); 756 if (execfd < 0) { 757 printf("Error while loading %s: %s\n", exec_path, strerror(errno)); 758 _exit(EXIT_FAILURE); 759 } 760 } 761 762 /* Resolve executable file name to full path name */ 763 if (realpath(exec_path, real_exec_path)) { 764 exec_path = real_exec_path; 765 } 766 767 /* 768 * get binfmt_misc flags 769 */ 770 preserve_argv0 = !!(qemu_getauxval(AT_FLAGS) & AT_FLAGS_PRESERVE_ARGV0); 771 772 /* 773 * Manage binfmt-misc preserve-arg[0] flag 774 * argv[optind] full path to the binary 775 * argv[optind + 1] original argv[0] 776 */ 777 if (optind + 1 < argc && preserve_argv0) { 778 optind++; 779 } 780 781 if (cpu_model == NULL) { 782 cpu_model = cpu_get_model(get_elf_eflags(execfd)); 783 } 784 cpu_type = parse_cpu_option(cpu_model); 785 786 /* init tcg before creating CPUs and to get qemu_host_page_size */ 787 { 788 AccelState *accel = current_accel(); 789 AccelClass *ac = ACCEL_GET_CLASS(accel); 790 791 accel_init_interfaces(ac); 792 object_property_set_bool(OBJECT(accel), "one-insn-per-tb", 793 opt_one_insn_per_tb, &error_abort); 794 ac->init_machine(NULL); 795 } 796 cpu = cpu_create(cpu_type); 797 env = cpu->env_ptr; 798 cpu_reset(cpu); 799 thread_cpu = cpu; 800 801 /* 802 * Reserving too much vm space via mmap can run into problems 803 * with rlimits, oom due to page table creation, etc. We will 804 * still try it, if directed by the command-line option, but 805 * not by default. 806 */ 807 max_reserved_va = MAX_RESERVED_VA(cpu); 808 if (reserved_va != 0) { 809 if ((reserved_va + 1) % qemu_host_page_size) { 810 char *s = size_to_str(qemu_host_page_size); 811 fprintf(stderr, "Reserved virtual address not aligned mod %s\n", s); 812 g_free(s); 813 exit(EXIT_FAILURE); 814 } 815 if (max_reserved_va && reserved_va > max_reserved_va) { 816 fprintf(stderr, "Reserved virtual address too big\n"); 817 exit(EXIT_FAILURE); 818 } 819 } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) { 820 /* MAX_RESERVED_VA + 1 is a large power of 2, so is aligned. */ 821 reserved_va = max_reserved_va; 822 } 823 824 /* 825 * Temporarily disable 826 * "comparison is always false due to limited range of data type" 827 * due to comparison between (possible) uint64_t and uintptr_t. 828 */ 829 #pragma GCC diagnostic push 830 #pragma GCC diagnostic ignored "-Wtype-limits" 831 832 /* 833 * Select an initial value for task_unmapped_base that is in range. 834 */ 835 if (reserved_va) { 836 if (TASK_UNMAPPED_BASE < reserved_va) { 837 task_unmapped_base = TASK_UNMAPPED_BASE; 838 } else { 839 /* The most common default formula is TASK_SIZE / 3. */ 840 task_unmapped_base = TARGET_PAGE_ALIGN(reserved_va / 3); 841 } 842 } else if (TASK_UNMAPPED_BASE < UINTPTR_MAX) { 843 task_unmapped_base = TASK_UNMAPPED_BASE; 844 } else { 845 /* 32-bit host: pick something medium size. */ 846 task_unmapped_base = 0x10000000; 847 } 848 mmap_next_start = task_unmapped_base; 849 850 /* Similarly for elf_et_dyn_base. */ 851 if (reserved_va) { 852 if (ELF_ET_DYN_BASE < reserved_va) { 853 elf_et_dyn_base = ELF_ET_DYN_BASE; 854 } else { 855 /* The most common default formula is TASK_SIZE / 3 * 2. */ 856 elf_et_dyn_base = TARGET_PAGE_ALIGN(reserved_va / 3) * 2; 857 } 858 } else if (ELF_ET_DYN_BASE < UINTPTR_MAX) { 859 elf_et_dyn_base = ELF_ET_DYN_BASE; 860 } else { 861 /* 32-bit host: pick something medium size. */ 862 elf_et_dyn_base = 0x18000000; 863 } 864 865 #pragma GCC diagnostic pop 866 867 { 868 Error *err = NULL; 869 if (seed_optarg != NULL) { 870 qemu_guest_random_seed_main(seed_optarg, &err); 871 } else { 872 qcrypto_init(&err); 873 } 874 if (err) { 875 error_reportf_err(err, "cannot initialize crypto: "); 876 exit(1); 877 } 878 } 879 880 target_environ = envlist_to_environ(envlist, NULL); 881 envlist_free(envlist); 882 883 /* 884 * Read in mmap_min_addr kernel parameter. This value is used 885 * When loading the ELF image to determine whether guest_base 886 * is needed. It is also used in mmap_find_vma. 887 */ 888 { 889 FILE *fp; 890 891 if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) { 892 unsigned long tmp; 893 if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) { 894 mmap_min_addr = tmp; 895 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n", 896 mmap_min_addr); 897 } 898 fclose(fp); 899 } 900 } 901 902 /* 903 * We prefer to not make NULL pointers accessible to QEMU. 904 * If we're in a chroot with no /proc, fall back to 1 page. 905 */ 906 if (mmap_min_addr == 0) { 907 mmap_min_addr = qemu_host_page_size; 908 qemu_log_mask(CPU_LOG_PAGE, 909 "host mmap_min_addr=0x%lx (fallback)\n", 910 mmap_min_addr); 911 } 912 913 /* 914 * Prepare copy of argv vector for target. 915 */ 916 target_argc = argc - optind; 917 target_argv = calloc(target_argc + 1, sizeof (char *)); 918 if (target_argv == NULL) { 919 (void) fprintf(stderr, "Unable to allocate memory for target_argv\n"); 920 exit(EXIT_FAILURE); 921 } 922 923 /* 924 * If argv0 is specified (using '-0' switch) we replace 925 * argv[0] pointer with the given one. 926 */ 927 i = 0; 928 if (argv0 != NULL) { 929 target_argv[i++] = strdup(argv0); 930 } 931 for (; i < target_argc; i++) { 932 target_argv[i] = strdup(argv[optind + i]); 933 } 934 target_argv[target_argc] = NULL; 935 936 ts = g_new0(TaskState, 1); 937 init_task_state(ts); 938 /* build Task State */ 939 ts->info = info; 940 ts->bprm = &bprm; 941 cpu->opaque = ts; 942 task_settid(ts); 943 944 fd_trans_init(); 945 946 ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs, 947 info, &bprm); 948 if (ret != 0) { 949 printf("Error while loading %s: %s\n", exec_path, strerror(-ret)); 950 _exit(EXIT_FAILURE); 951 } 952 953 for (wrk = target_environ; *wrk; wrk++) { 954 g_free(*wrk); 955 } 956 957 g_free(target_environ); 958 959 if (qemu_loglevel_mask(CPU_LOG_PAGE)) { 960 FILE *f = qemu_log_trylock(); 961 if (f) { 962 fprintf(f, "guest_base %p\n", (void *)guest_base); 963 fprintf(f, "page layout changed following binary load\n"); 964 page_dump(f); 965 966 fprintf(f, "end_code 0x" TARGET_ABI_FMT_lx "\n", 967 info->end_code); 968 fprintf(f, "start_code 0x" TARGET_ABI_FMT_lx "\n", 969 info->start_code); 970 fprintf(f, "start_data 0x" TARGET_ABI_FMT_lx "\n", 971 info->start_data); 972 fprintf(f, "end_data 0x" TARGET_ABI_FMT_lx "\n", 973 info->end_data); 974 fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n", 975 info->start_stack); 976 fprintf(f, "brk 0x" TARGET_ABI_FMT_lx "\n", 977 info->brk); 978 fprintf(f, "entry 0x" TARGET_ABI_FMT_lx "\n", 979 info->entry); 980 fprintf(f, "argv_start 0x" TARGET_ABI_FMT_lx "\n", 981 info->argv); 982 fprintf(f, "env_start 0x" TARGET_ABI_FMT_lx "\n", 983 info->envp); 984 fprintf(f, "auxv_start 0x" TARGET_ABI_FMT_lx "\n", 985 info->saved_auxv); 986 qemu_log_unlock(f); 987 } 988 } 989 990 target_set_brk(info->brk); 991 syscall_init(); 992 signal_init(); 993 994 /* Now that we've loaded the binary, GUEST_BASE is fixed. Delay 995 generating the prologue until now so that the prologue can take 996 the real value of GUEST_BASE into account. */ 997 tcg_prologue_init(tcg_ctx); 998 999 target_cpu_copy_regs(env, regs); 1000 1001 if (gdbstub) { 1002 if (gdbserver_start(gdbstub) < 0) { 1003 fprintf(stderr, "qemu: could not open gdbserver on %s\n", 1004 gdbstub); 1005 exit(EXIT_FAILURE); 1006 } 1007 gdb_handlesig(cpu, 0); 1008 } 1009 1010 #ifdef CONFIG_SEMIHOSTING 1011 qemu_semihosting_guestfd_init(); 1012 #endif 1013 1014 cpu_loop(env); 1015 /* never exits */ 1016 return 0; 1017 } 1018