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 "user/guest-base.h"
42 #include "exec/exec-all.h"
43 #include "exec/gdbstub.h"
44 #include "gdbstub/user.h"
45 #include "tcg/startup.h"
46 #include "qemu/timer.h"
47 #include "qemu/envlist.h"
48 #include "qemu/guest-random.h"
49 #include "elf.h"
50 #include "trace/control.h"
51 #include "target_elf.h"
52 #include "cpu_loop-common.h"
53 #include "crypto/init.h"
54 #include "fd-trans.h"
55 #include "signal-common.h"
56 #include "loader.h"
57 #include "user-mmap.h"
58 #include "tcg/perf.h"
59 #include "exec/page-vary.h"
60
61 #ifdef CONFIG_SEMIHOSTING
62 #include "semihosting/semihost.h"
63 #endif
64
65 #ifndef AT_FLAGS_PRESERVE_ARGV0
66 #define AT_FLAGS_PRESERVE_ARGV0_BIT 0
67 #define AT_FLAGS_PRESERVE_ARGV0 (1 << AT_FLAGS_PRESERVE_ARGV0_BIT)
68 #endif
69
70 char *exec_path;
71 char real_exec_path[PATH_MAX];
72
73 static bool opt_one_insn_per_tb;
74 static const char *argv0;
75 static const char *gdbstub;
76 static envlist_t *envlist;
77 static const char *cpu_model;
78 static const char *cpu_type;
79 static const char *seed_optarg;
80 unsigned long mmap_min_addr;
81 uintptr_t guest_base;
82 bool have_guest_base;
83
84 /*
85 * Used to implement backwards-compatibility for the `-strace`, and
86 * QEMU_STRACE options. Without this, the QEMU_LOG can be overwritten by
87 * -strace, or vice versa.
88 */
89 static bool enable_strace;
90
91 /*
92 * The last log mask given by the user in an environment variable or argument.
93 * Used to support command line arguments overriding environment variables.
94 */
95 static int last_log_mask;
96 static const char *last_log_filename;
97
98 /*
99 * When running 32-on-64 we should make sure we can fit all of the possible
100 * guest address space into a contiguous chunk of virtual host memory.
101 *
102 * This way we will never overlap with our own libraries or binaries or stack
103 * or anything else that QEMU maps.
104 *
105 * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
106 * of the address for the kernel. Some cpus rely on this and user space
107 * uses the high bit(s) for pointer tagging and the like. For them, we
108 * must preserve the expected address space.
109 */
110 #ifndef MAX_RESERVED_VA
111 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
112 # if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
113 (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
114 # define MAX_RESERVED_VA(CPU) 0xfffffffful
115 # else
116 # define MAX_RESERVED_VA(CPU) ((1ul << TARGET_VIRT_ADDR_SPACE_BITS) - 1)
117 # endif
118 # else
119 # define MAX_RESERVED_VA(CPU) 0
120 # endif
121 #endif
122
123 unsigned long reserved_va;
124
125 static void usage(int exitcode);
126
127 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
128 const char *qemu_uname_release;
129
130 #if !defined(TARGET_DEFAULT_STACK_SIZE)
131 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
132 we allocate a bigger stack. Need a better solution, for example
133 by remapping the process stack directly at the right place */
134 #define TARGET_DEFAULT_STACK_SIZE 8 * 1024 * 1024UL
135 #endif
136
137 unsigned long guest_stack_size = TARGET_DEFAULT_STACK_SIZE;
138
139 /***********************************************************/
140 /* Helper routines for implementing atomic operations. */
141
142 /* Make sure everything is in a consistent state for calling fork(). */
fork_start(void)143 void fork_start(void)
144 {
145 start_exclusive();
146 mmap_fork_start();
147 cpu_list_lock();
148 qemu_plugin_user_prefork_lock();
149 gdbserver_fork_start();
150 }
151
fork_end(pid_t pid)152 void fork_end(pid_t pid)
153 {
154 bool child = pid == 0;
155
156 qemu_plugin_user_postfork(child);
157 mmap_fork_end(child);
158 if (child) {
159 CPUState *cpu, *next_cpu;
160 /* Child processes created by fork() only have a single thread.
161 Discard information about the parent threads. */
162 CPU_FOREACH_SAFE(cpu, next_cpu) {
163 if (cpu != thread_cpu) {
164 QTAILQ_REMOVE_RCU(&cpus_queue, cpu, node);
165 }
166 }
167 qemu_init_cpu_list();
168 get_task_state(thread_cpu)->ts_tid = qemu_get_thread_id();
169 } else {
170 cpu_list_unlock();
171 }
172 gdbserver_fork_end(thread_cpu, pid);
173 /*
174 * qemu_init_cpu_list() reinitialized the child exclusive state, but we
175 * also need to keep current_cpu consistent, so call end_exclusive() for
176 * both child and parent.
177 */
178 end_exclusive();
179 }
180
181 __thread CPUState *thread_cpu;
182
qemu_cpu_is_self(CPUState * cpu)183 bool qemu_cpu_is_self(CPUState *cpu)
184 {
185 return thread_cpu == cpu;
186 }
187
qemu_cpu_kick(CPUState * cpu)188 void qemu_cpu_kick(CPUState *cpu)
189 {
190 cpu_exit(cpu);
191 }
192
task_settid(TaskState * ts)193 void task_settid(TaskState *ts)
194 {
195 if (ts->ts_tid == 0) {
196 ts->ts_tid = (pid_t)syscall(SYS_gettid);
197 }
198 }
199
stop_all_tasks(void)200 void stop_all_tasks(void)
201 {
202 /*
203 * We trust that when using NPTL, start_exclusive()
204 * handles thread stopping correctly.
205 */
206 start_exclusive();
207 }
208
209 /* Assumes contents are already zeroed. */
init_task_state(TaskState * ts)210 void init_task_state(TaskState *ts)
211 {
212 long ticks_per_sec;
213 struct timespec bt;
214
215 ts->used = 1;
216 ts->sigaltstack_used = (struct target_sigaltstack) {
217 .ss_sp = 0,
218 .ss_size = 0,
219 .ss_flags = TARGET_SS_DISABLE,
220 };
221
222 /* Capture task start time relative to system boot */
223
224 ticks_per_sec = sysconf(_SC_CLK_TCK);
225
226 if ((ticks_per_sec > 0) && !clock_gettime(CLOCK_BOOTTIME, &bt)) {
227 /* start_boottime is expressed in clock ticks */
228 ts->start_boottime = bt.tv_sec * (uint64_t) ticks_per_sec;
229 ts->start_boottime += bt.tv_nsec * (uint64_t) ticks_per_sec /
230 NANOSECONDS_PER_SECOND;
231 }
232 }
233
cpu_copy(CPUArchState * env)234 CPUArchState *cpu_copy(CPUArchState *env)
235 {
236 CPUState *cpu = env_cpu(env);
237 CPUState *new_cpu = cpu_create(cpu_type);
238 CPUArchState *new_env = cpu_env(new_cpu);
239 CPUBreakpoint *bp;
240
241 /* Reset non arch specific state */
242 cpu_reset(new_cpu);
243
244 new_cpu->tcg_cflags = cpu->tcg_cflags;
245 memcpy(new_env, env, sizeof(CPUArchState));
246 #if defined(TARGET_I386) || defined(TARGET_X86_64)
247 new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES,
248 PROT_READ | PROT_WRITE,
249 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
250 memcpy(g2h_untagged(new_env->gdt.base), g2h_untagged(env->gdt.base),
251 sizeof(uint64_t) * TARGET_GDT_ENTRIES);
252 OBJECT(new_cpu)->free = OBJECT(cpu)->free;
253 #endif
254
255 /* Clone all break/watchpoints.
256 Note: Once we support ptrace with hw-debug register access, make sure
257 BP_CPU break/watchpoints are handled correctly on clone. */
258 QTAILQ_INIT(&new_cpu->breakpoints);
259 QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
260 cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
261 }
262
263 return new_env;
264 }
265
handle_arg_help(const char * arg)266 static void handle_arg_help(const char *arg)
267 {
268 usage(EXIT_SUCCESS);
269 }
270
handle_arg_log(const char * arg)271 static void handle_arg_log(const char *arg)
272 {
273 last_log_mask = qemu_str_to_log_mask(arg);
274 if (!last_log_mask) {
275 qemu_print_log_usage(stdout);
276 exit(EXIT_FAILURE);
277 }
278 }
279
handle_arg_dfilter(const char * arg)280 static void handle_arg_dfilter(const char *arg)
281 {
282 qemu_set_dfilter_ranges(arg, &error_fatal);
283 }
284
handle_arg_log_filename(const char * arg)285 static void handle_arg_log_filename(const char *arg)
286 {
287 last_log_filename = arg;
288 }
289
handle_arg_set_env(const char * arg)290 static void handle_arg_set_env(const char *arg)
291 {
292 char *r, *p, *token;
293 r = p = strdup(arg);
294 while ((token = strsep(&p, ",")) != NULL) {
295 if (envlist_setenv(envlist, token) != 0) {
296 usage(EXIT_FAILURE);
297 }
298 }
299 free(r);
300 }
301
handle_arg_unset_env(const char * arg)302 static void handle_arg_unset_env(const char *arg)
303 {
304 char *r, *p, *token;
305 r = p = strdup(arg);
306 while ((token = strsep(&p, ",")) != NULL) {
307 if (envlist_unsetenv(envlist, token) != 0) {
308 usage(EXIT_FAILURE);
309 }
310 }
311 free(r);
312 }
313
handle_arg_argv0(const char * arg)314 static void handle_arg_argv0(const char *arg)
315 {
316 argv0 = strdup(arg);
317 }
318
handle_arg_stack_size(const char * arg)319 static void handle_arg_stack_size(const char *arg)
320 {
321 char *p;
322 guest_stack_size = strtoul(arg, &p, 0);
323 if (guest_stack_size == 0) {
324 usage(EXIT_FAILURE);
325 }
326
327 if (*p == 'M') {
328 guest_stack_size *= MiB;
329 } else if (*p == 'k' || *p == 'K') {
330 guest_stack_size *= KiB;
331 }
332 }
333
handle_arg_ld_prefix(const char * arg)334 static void handle_arg_ld_prefix(const char *arg)
335 {
336 interp_prefix = strdup(arg);
337 }
338
handle_arg_pagesize(const char * arg)339 static void handle_arg_pagesize(const char *arg)
340 {
341 unsigned size, want = qemu_real_host_page_size();
342
343 if (qemu_strtoui(arg, NULL, 10, &size) || size != want) {
344 warn_report("Deprecated page size option cannot "
345 "change host page size (%u)", want);
346 }
347 }
348
handle_arg_seed(const char * arg)349 static void handle_arg_seed(const char *arg)
350 {
351 seed_optarg = arg;
352 }
353
handle_arg_gdb(const char * arg)354 static void handle_arg_gdb(const char *arg)
355 {
356 gdbstub = g_strdup(arg);
357 }
358
handle_arg_uname(const char * arg)359 static void handle_arg_uname(const char *arg)
360 {
361 qemu_uname_release = strdup(arg);
362 }
363
handle_arg_cpu(const char * arg)364 static void handle_arg_cpu(const char *arg)
365 {
366 cpu_model = strdup(arg);
367 if (cpu_model == NULL || is_help_option(cpu_model)) {
368 list_cpus();
369 exit(EXIT_FAILURE);
370 }
371 }
372
handle_arg_guest_base(const char * arg)373 static void handle_arg_guest_base(const char *arg)
374 {
375 guest_base = strtol(arg, NULL, 0);
376 have_guest_base = true;
377 }
378
handle_arg_reserved_va(const char * arg)379 static void handle_arg_reserved_va(const char *arg)
380 {
381 char *p;
382 int shift = 0;
383 unsigned long val;
384
385 val = strtoul(arg, &p, 0);
386 switch (*p) {
387 case 'k':
388 case 'K':
389 shift = 10;
390 break;
391 case 'M':
392 shift = 20;
393 break;
394 case 'G':
395 shift = 30;
396 break;
397 }
398 if (shift) {
399 unsigned long unshifted = val;
400 p++;
401 val <<= shift;
402 if (val >> shift != unshifted) {
403 fprintf(stderr, "Reserved virtual address too big\n");
404 exit(EXIT_FAILURE);
405 }
406 }
407 if (*p) {
408 fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
409 exit(EXIT_FAILURE);
410 }
411 /* The representation is size - 1, with 0 remaining "default". */
412 reserved_va = val ? val - 1 : 0;
413 }
414
handle_arg_one_insn_per_tb(const char * arg)415 static void handle_arg_one_insn_per_tb(const char *arg)
416 {
417 opt_one_insn_per_tb = true;
418 }
419
handle_arg_strace(const char * arg)420 static void handle_arg_strace(const char *arg)
421 {
422 enable_strace = true;
423 }
424
handle_arg_version(const char * arg)425 static void handle_arg_version(const char *arg)
426 {
427 printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
428 "\n" QEMU_COPYRIGHT "\n");
429 exit(EXIT_SUCCESS);
430 }
431
handle_arg_trace(const char * arg)432 static void handle_arg_trace(const char *arg)
433 {
434 trace_opt_parse(arg);
435 }
436
437 #if defined(TARGET_XTENSA)
handle_arg_abi_call0(const char * arg)438 static void handle_arg_abi_call0(const char *arg)
439 {
440 xtensa_set_abi_call0();
441 }
442 #endif
443
handle_arg_perfmap(const char * arg)444 static void handle_arg_perfmap(const char *arg)
445 {
446 perf_enable_perfmap();
447 }
448
handle_arg_jitdump(const char * arg)449 static void handle_arg_jitdump(const char *arg)
450 {
451 perf_enable_jitdump();
452 }
453
454 static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
455
456 #ifdef CONFIG_PLUGIN
handle_arg_plugin(const char * arg)457 static void handle_arg_plugin(const char *arg)
458 {
459 qemu_plugin_opt_parse(arg, &plugins);
460 }
461 #endif
462
463 struct qemu_argument {
464 const char *argv;
465 const char *env;
466 bool has_arg;
467 void (*handle_opt)(const char *arg);
468 const char *example;
469 const char *help;
470 };
471
472 static const struct qemu_argument arg_table[] = {
473 {"h", "", false, handle_arg_help,
474 "", "print this help"},
475 {"help", "", false, handle_arg_help,
476 "", ""},
477 {"g", "QEMU_GDB", true, handle_arg_gdb,
478 "port", "wait gdb connection to 'port'"},
479 {"L", "QEMU_LD_PREFIX", true, handle_arg_ld_prefix,
480 "path", "set the elf interpreter prefix to 'path'"},
481 {"s", "QEMU_STACK_SIZE", true, handle_arg_stack_size,
482 "size", "set the stack size to 'size' bytes"},
483 {"cpu", "QEMU_CPU", true, handle_arg_cpu,
484 "model", "select CPU (-cpu help for list)"},
485 {"E", "QEMU_SET_ENV", true, handle_arg_set_env,
486 "var=value", "sets targets environment variable (see below)"},
487 {"U", "QEMU_UNSET_ENV", true, handle_arg_unset_env,
488 "var", "unsets targets environment variable (see below)"},
489 {"0", "QEMU_ARGV0", true, handle_arg_argv0,
490 "argv0", "forces target process argv[0] to be 'argv0'"},
491 {"r", "QEMU_UNAME", true, handle_arg_uname,
492 "uname", "set qemu uname release string to 'uname'"},
493 {"B", "QEMU_GUEST_BASE", true, handle_arg_guest_base,
494 "address", "set guest_base address to 'address'"},
495 {"R", "QEMU_RESERVED_VA", true, handle_arg_reserved_va,
496 "size", "reserve 'size' bytes for guest virtual address space"},
497 {"d", "QEMU_LOG", true, handle_arg_log,
498 "item[,...]", "enable logging of specified items "
499 "(use '-d help' for a list of items)"},
500 {"dfilter", "QEMU_DFILTER", true, handle_arg_dfilter,
501 "range[,...]","filter logging based on address range"},
502 {"D", "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
503 "logfile", "write logs to 'logfile' (default stderr)"},
504 {"p", "QEMU_PAGESIZE", true, handle_arg_pagesize,
505 "pagesize", "deprecated change to host page size"},
506 {"one-insn-per-tb",
507 "QEMU_ONE_INSN_PER_TB", false, handle_arg_one_insn_per_tb,
508 "", "run with one guest instruction per emulated TB"},
509 {"strace", "QEMU_STRACE", false, handle_arg_strace,
510 "", "log system calls"},
511 {"seed", "QEMU_RAND_SEED", true, handle_arg_seed,
512 "", "Seed for pseudo-random number generator"},
513 {"trace", "QEMU_TRACE", true, handle_arg_trace,
514 "", "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
515 #ifdef CONFIG_PLUGIN
516 {"plugin", "QEMU_PLUGIN", true, handle_arg_plugin,
517 "", "[file=]<file>[,<argname>=<argvalue>]"},
518 #endif
519 {"version", "QEMU_VERSION", false, handle_arg_version,
520 "", "display version information and exit"},
521 #if defined(TARGET_XTENSA)
522 {"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
523 "", "assume CALL0 Xtensa ABI"},
524 #endif
525 {"perfmap", "QEMU_PERFMAP", false, handle_arg_perfmap,
526 "", "Generate a /tmp/perf-${pid}.map file for perf"},
527 {"jitdump", "QEMU_JITDUMP", false, handle_arg_jitdump,
528 "", "Generate a jit-${pid}.dump file for perf"},
529 {NULL, NULL, false, NULL, NULL, NULL}
530 };
531
usage(int exitcode)532 static void usage(int exitcode)
533 {
534 const struct qemu_argument *arginfo;
535 int maxarglen;
536 int maxenvlen;
537
538 printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
539 "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
540 "\n"
541 "Options and associated environment variables:\n"
542 "\n");
543
544 /* Calculate column widths. We must always have at least enough space
545 * for the column header.
546 */
547 maxarglen = strlen("Argument");
548 maxenvlen = strlen("Env-variable");
549
550 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
551 int arglen = strlen(arginfo->argv);
552 if (arginfo->has_arg) {
553 arglen += strlen(arginfo->example) + 1;
554 }
555 if (strlen(arginfo->env) > maxenvlen) {
556 maxenvlen = strlen(arginfo->env);
557 }
558 if (arglen > maxarglen) {
559 maxarglen = arglen;
560 }
561 }
562
563 printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
564 maxenvlen, "Env-variable");
565
566 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
567 if (arginfo->has_arg) {
568 printf("-%s %-*s %-*s %s\n", arginfo->argv,
569 (int)(maxarglen - strlen(arginfo->argv) - 1),
570 arginfo->example, maxenvlen, arginfo->env, arginfo->help);
571 } else {
572 printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
573 maxenvlen, arginfo->env,
574 arginfo->help);
575 }
576 }
577
578 printf("\n"
579 "Defaults:\n"
580 "QEMU_LD_PREFIX = %s\n"
581 "QEMU_STACK_SIZE = %ld byte\n",
582 interp_prefix,
583 guest_stack_size);
584
585 printf("\n"
586 "You can use -E and -U options or the QEMU_SET_ENV and\n"
587 "QEMU_UNSET_ENV environment variables to set and unset\n"
588 "environment variables for the target process.\n"
589 "It is possible to provide several variables by separating them\n"
590 "by commas in getsubopt(3) style. Additionally it is possible to\n"
591 "provide the -E and -U options multiple times.\n"
592 "The following lines are equivalent:\n"
593 " -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
594 " -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
595 " QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
596 "Note that if you provide several changes to a single variable\n"
597 "the last change will stay in effect.\n"
598 "\n"
599 QEMU_HELP_BOTTOM "\n");
600
601 exit(exitcode);
602 }
603
parse_args(int argc,char ** argv)604 static int parse_args(int argc, char **argv)
605 {
606 const char *r;
607 int optind;
608 const struct qemu_argument *arginfo;
609
610 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
611 if (arginfo->env == NULL) {
612 continue;
613 }
614
615 r = getenv(arginfo->env);
616 if (r != NULL) {
617 arginfo->handle_opt(r);
618 }
619 }
620
621 optind = 1;
622 for (;;) {
623 if (optind >= argc) {
624 break;
625 }
626 r = argv[optind];
627 if (r[0] != '-') {
628 break;
629 }
630 optind++;
631 r++;
632 if (!strcmp(r, "-")) {
633 break;
634 }
635 /* Treat --foo the same as -foo. */
636 if (r[0] == '-') {
637 r++;
638 }
639
640 for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
641 if (!strcmp(r, arginfo->argv)) {
642 if (arginfo->has_arg) {
643 if (optind >= argc) {
644 (void) fprintf(stderr,
645 "qemu: missing argument for option '%s'\n", r);
646 exit(EXIT_FAILURE);
647 }
648 arginfo->handle_opt(argv[optind]);
649 optind++;
650 } else {
651 arginfo->handle_opt(NULL);
652 }
653 break;
654 }
655 }
656
657 /* no option matched the current argv */
658 if (arginfo->handle_opt == NULL) {
659 (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
660 exit(EXIT_FAILURE);
661 }
662 }
663
664 if (optind >= argc) {
665 (void) fprintf(stderr, "qemu: no user program specified\n");
666 exit(EXIT_FAILURE);
667 }
668
669 exec_path = argv[optind];
670
671 return optind;
672 }
673
main(int argc,char ** argv,char ** envp)674 int main(int argc, char **argv, char **envp)
675 {
676 struct target_pt_regs regs1, *regs = ®s1;
677 struct image_info info1, *info = &info1;
678 struct linux_binprm bprm;
679 TaskState *ts;
680 CPUArchState *env;
681 CPUState *cpu;
682 int optind;
683 char **target_environ, **wrk;
684 char **target_argv;
685 int target_argc;
686 int i;
687 int ret;
688 int execfd;
689 int host_page_size;
690 unsigned long max_reserved_va;
691 bool preserve_argv0;
692
693 error_init(argv[0]);
694 module_call_init(MODULE_INIT_TRACE);
695 qemu_init_cpu_list();
696 module_call_init(MODULE_INIT_QOM);
697
698 envlist = envlist_create();
699
700 /*
701 * add current environment into the list
702 * envlist_setenv adds to the front of the list; to preserve environ
703 * order add from back to front
704 */
705 for (wrk = environ; *wrk != NULL; wrk++) {
706 continue;
707 }
708 while (wrk != environ) {
709 wrk--;
710 (void) envlist_setenv(envlist, *wrk);
711 }
712
713 /* Read the stack limit from the kernel. If it's "unlimited",
714 then we can do little else besides use the default. */
715 {
716 struct rlimit lim;
717 if (getrlimit(RLIMIT_STACK, &lim) == 0
718 && lim.rlim_cur != RLIM_INFINITY
719 && lim.rlim_cur == (target_long)lim.rlim_cur
720 && lim.rlim_cur > guest_stack_size) {
721 guest_stack_size = lim.rlim_cur;
722 }
723 }
724
725 cpu_model = NULL;
726
727 qemu_add_opts(&qemu_trace_opts);
728 qemu_plugin_add_opts();
729
730 optind = parse_args(argc, argv);
731
732 qemu_set_log_filename_flags(last_log_filename,
733 last_log_mask | (enable_strace * LOG_STRACE),
734 &error_fatal);
735
736 if (!trace_init_backends()) {
737 exit(1);
738 }
739 trace_init_file();
740 qemu_plugin_load_list(&plugins, &error_fatal);
741
742 /* Zero out regs */
743 memset(regs, 0, sizeof(struct target_pt_regs));
744
745 /* Zero out image_info */
746 memset(info, 0, sizeof(struct image_info));
747
748 memset(&bprm, 0, sizeof (bprm));
749
750 /* Scan interp_prefix dir for replacement files. */
751 init_paths(interp_prefix);
752
753 init_qemu_uname_release();
754
755 /*
756 * Manage binfmt-misc open-binary flag
757 */
758 execfd = qemu_getauxval(AT_EXECFD);
759 if (execfd == 0) {
760 execfd = open(exec_path, O_RDONLY);
761 if (execfd < 0) {
762 printf("Error while loading %s: %s\n", exec_path, strerror(errno));
763 _exit(EXIT_FAILURE);
764 }
765 }
766
767 /* Resolve executable file name to full path name */
768 if (realpath(exec_path, real_exec_path)) {
769 exec_path = real_exec_path;
770 }
771
772 /*
773 * get binfmt_misc flags
774 */
775 preserve_argv0 = !!(qemu_getauxval(AT_FLAGS) & AT_FLAGS_PRESERVE_ARGV0);
776
777 /*
778 * Manage binfmt-misc preserve-arg[0] flag
779 * argv[optind] full path to the binary
780 * argv[optind + 1] original argv[0]
781 */
782 if (optind + 1 < argc && preserve_argv0) {
783 optind++;
784 }
785
786 if (cpu_model == NULL) {
787 cpu_model = cpu_get_model(get_elf_eflags(execfd));
788 }
789 cpu_type = parse_cpu_option(cpu_model);
790
791 /* init tcg before creating CPUs */
792 {
793 AccelState *accel = current_accel();
794 AccelClass *ac = ACCEL_GET_CLASS(accel);
795
796 accel_init_interfaces(ac);
797 object_property_set_bool(OBJECT(accel), "one-insn-per-tb",
798 opt_one_insn_per_tb, &error_abort);
799 ac->init_machine(NULL);
800 }
801
802 /*
803 * Finalize page size before creating CPUs.
804 * This will do nothing if !TARGET_PAGE_BITS_VARY.
805 * The most efficient setting is to match the host.
806 */
807 host_page_size = qemu_real_host_page_size();
808 set_preferred_target_page_bits(ctz32(host_page_size));
809 finalize_target_page_bits();
810
811 cpu = cpu_create(cpu_type);
812 env = cpu_env(cpu);
813 cpu_reset(cpu);
814 thread_cpu = cpu;
815
816 /*
817 * Reserving too much vm space via mmap can run into problems
818 * with rlimits, oom due to page table creation, etc. We will
819 * still try it, if directed by the command-line option, but
820 * not by default.
821 */
822 max_reserved_va = MAX_RESERVED_VA(cpu);
823 if (reserved_va != 0) {
824 if ((reserved_va + 1) % host_page_size) {
825 char *s = size_to_str(host_page_size);
826 fprintf(stderr, "Reserved virtual address not aligned mod %s\n", s);
827 g_free(s);
828 exit(EXIT_FAILURE);
829 }
830 if (max_reserved_va && reserved_va > max_reserved_va) {
831 fprintf(stderr, "Reserved virtual address too big\n");
832 exit(EXIT_FAILURE);
833 }
834 } else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
835 /* MAX_RESERVED_VA + 1 is a large power of 2, so is aligned. */
836 reserved_va = max_reserved_va;
837 }
838
839 /*
840 * Temporarily disable
841 * "comparison is always false due to limited range of data type"
842 * due to comparison between (possible) uint64_t and uintptr_t.
843 */
844 #pragma GCC diagnostic push
845 #pragma GCC diagnostic ignored "-Wtype-limits"
846
847 /*
848 * Select an initial value for task_unmapped_base that is in range.
849 */
850 if (reserved_va) {
851 if (TASK_UNMAPPED_BASE < reserved_va) {
852 task_unmapped_base = TASK_UNMAPPED_BASE;
853 } else {
854 /* The most common default formula is TASK_SIZE / 3. */
855 task_unmapped_base = TARGET_PAGE_ALIGN(reserved_va / 3);
856 }
857 } else if (TASK_UNMAPPED_BASE < UINTPTR_MAX) {
858 task_unmapped_base = TASK_UNMAPPED_BASE;
859 } else {
860 /* 32-bit host: pick something medium size. */
861 task_unmapped_base = 0x10000000;
862 }
863 mmap_next_start = task_unmapped_base;
864
865 /* Similarly for elf_et_dyn_base. */
866 if (reserved_va) {
867 if (ELF_ET_DYN_BASE < reserved_va) {
868 elf_et_dyn_base = ELF_ET_DYN_BASE;
869 } else {
870 /* The most common default formula is TASK_SIZE / 3 * 2. */
871 elf_et_dyn_base = TARGET_PAGE_ALIGN(reserved_va / 3) * 2;
872 }
873 } else if (ELF_ET_DYN_BASE < UINTPTR_MAX) {
874 elf_et_dyn_base = ELF_ET_DYN_BASE;
875 } else {
876 /* 32-bit host: pick something medium size. */
877 elf_et_dyn_base = 0x18000000;
878 }
879
880 #pragma GCC diagnostic pop
881
882 {
883 Error *err = NULL;
884 if (seed_optarg != NULL) {
885 qemu_guest_random_seed_main(seed_optarg, &err);
886 } else {
887 qcrypto_init(&err);
888 }
889 if (err) {
890 error_reportf_err(err, "cannot initialize crypto: ");
891 exit(1);
892 }
893 }
894
895 target_environ = envlist_to_environ(envlist, NULL);
896 envlist_free(envlist);
897
898 /*
899 * Read in mmap_min_addr kernel parameter. This value is used
900 * When loading the ELF image to determine whether guest_base
901 * is needed. It is also used in mmap_find_vma.
902 */
903 {
904 FILE *fp;
905
906 if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
907 unsigned long tmp;
908 if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
909 mmap_min_addr = MAX(tmp, host_page_size);
910 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
911 mmap_min_addr);
912 }
913 fclose(fp);
914 }
915 }
916
917 /*
918 * We prefer to not make NULL pointers accessible to QEMU.
919 * If we're in a chroot with no /proc, fall back to 1 page.
920 */
921 if (mmap_min_addr == 0) {
922 mmap_min_addr = host_page_size;
923 qemu_log_mask(CPU_LOG_PAGE,
924 "host mmap_min_addr=0x%lx (fallback)\n",
925 mmap_min_addr);
926 }
927
928 /*
929 * Prepare copy of argv vector for target.
930 */
931 target_argc = argc - optind;
932 target_argv = g_new0(char *, target_argc + 1);
933
934 /*
935 * If argv0 is specified (using '-0' switch) we replace
936 * argv[0] pointer with the given one.
937 */
938 i = 0;
939 if (argv0 != NULL) {
940 target_argv[i++] = strdup(argv0);
941 }
942 for (; i < target_argc; i++) {
943 target_argv[i] = strdup(argv[optind + i]);
944 }
945 target_argv[target_argc] = NULL;
946
947 ts = g_new0(TaskState, 1);
948 init_task_state(ts);
949 /* build Task State */
950 ts->info = info;
951 ts->bprm = &bprm;
952 cpu->opaque = ts;
953 task_settid(ts);
954
955 fd_trans_init();
956
957 ret = loader_exec(execfd, exec_path, target_argv, target_environ, regs,
958 info, &bprm);
959 if (ret != 0) {
960 printf("Error while loading %s: %s\n", exec_path, strerror(-ret));
961 _exit(EXIT_FAILURE);
962 }
963
964 for (wrk = target_environ; *wrk; wrk++) {
965 g_free(*wrk);
966 }
967
968 g_free(target_environ);
969
970 if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
971 FILE *f = qemu_log_trylock();
972 if (f) {
973 fprintf(f, "guest_base %p\n", (void *)guest_base);
974 fprintf(f, "page layout changed following binary load\n");
975 page_dump(f);
976
977 fprintf(f, "end_code 0x" TARGET_ABI_FMT_lx "\n",
978 info->end_code);
979 fprintf(f, "start_code 0x" TARGET_ABI_FMT_lx "\n",
980 info->start_code);
981 fprintf(f, "start_data 0x" TARGET_ABI_FMT_lx "\n",
982 info->start_data);
983 fprintf(f, "end_data 0x" TARGET_ABI_FMT_lx "\n",
984 info->end_data);
985 fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n",
986 info->start_stack);
987 fprintf(f, "brk 0x" TARGET_ABI_FMT_lx "\n",
988 info->brk);
989 fprintf(f, "entry 0x" TARGET_ABI_FMT_lx "\n",
990 info->entry);
991 fprintf(f, "argv_start 0x" TARGET_ABI_FMT_lx "\n",
992 info->argv);
993 fprintf(f, "env_start 0x" TARGET_ABI_FMT_lx "\n",
994 info->envp);
995 fprintf(f, "auxv_start 0x" TARGET_ABI_FMT_lx "\n",
996 info->saved_auxv);
997 qemu_log_unlock(f);
998 }
999 }
1000
1001 target_set_brk(info->brk);
1002 syscall_init();
1003 signal_init();
1004
1005 /* Now that we've loaded the binary, GUEST_BASE is fixed. Delay
1006 generating the prologue until now so that the prologue can take
1007 the real value of GUEST_BASE into account. */
1008 tcg_prologue_init();
1009
1010 target_cpu_copy_regs(env, regs);
1011
1012 if (gdbstub) {
1013 if (gdbserver_start(gdbstub) < 0) {
1014 fprintf(stderr, "qemu: could not open gdbserver on %s\n",
1015 gdbstub);
1016 exit(EXIT_FAILURE);
1017 }
1018 gdb_handlesig(cpu, 0, NULL, NULL, 0);
1019 }
1020
1021 #ifdef CONFIG_SEMIHOSTING
1022 qemu_semihosting_guestfd_init();
1023 #endif
1024
1025 cpu_loop(env);
1026 /* never exits */
1027 return 0;
1028 }
1029