osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56
  57 #include <mach_assert.h>
  58 #include <mach_kdb.h>
  59 #include <mach_kgdb.h>
  60 #include <mach_kdp.h>
  61
  62 #include <kern/cpu_number.h>
  63 #include <kern/kalloc.h>
  64 #include <kern/lock.h>
  65 #include <kern/spl.h>
  66 #include <kern/thread.h>
  67 #include <kern/assert.h>
  68 #include <kern/sched_prim.h>
  69 #include <kern/misc_protos.h>
  70 #include <kern/clock.h>
  71 #include <vm/vm_kern.h>
  72 #include <vm/pmap.h>
  73 #include <stdarg.h>
  74 #if !MACH_KDP
  75 #include <kdp/kdp_udp.h>
  76 #endif
  77
  78 #if defined(__i386__) || defined(__x86_64__)
  79 #include <i386/cpu_threads.h>
  80 #include <i386/pmCPU.h>
  81 #endif
  82
  83 #include <IOKit/IOPlatformExpert.h>
  84 #include <machine/pal_routines.h>
  85
  86 #include <sys/kdebug.h>
  87 #include <libkern/OSKextLibPrivate.h>
  88 #include <libkern/OSAtomic.h>
  89 #include <libkern/kernel_mach_header.h>
  90 #include <uuid/uuid.h>
  91
  92 unsigned int    halt_in_debugger = 0;
  93 unsigned int    switch_debugger = 0;
  94 unsigned int    current_debugger = 0;
  95 unsigned int    active_debugger = 0;
  96 unsigned int    debug_mode=0;
  97 unsigned int    disable_debug_output = TRUE;
  98 unsigned int    systemLogDiags = FALSE;
  99 unsigned int    panicDebugging = FALSE;
 100 unsigned int    logPanicDataToScreen = FALSE;
 101
 102 int mach_assert = 1;
 103
 104 const char              *panicstr = (char *) 0;
 105 decl_simple_lock_data(,panic_lock)
 106 int                     paniccpu;
 107 volatile int            panicwait;
 108 volatile unsigned int   nestedpanic= 0;
 109 unsigned int            panic_is_inited = 0;
 110 unsigned int            return_on_panic = 0;
 111 unsigned long           panic_caller;
 112
 113 #if CONFIG_EMBEDDED
 114 #define DEBUG_BUF_SIZE (PAGE_SIZE)
 115 #else
 116 #define DEBUG_BUF_SIZE (3 * PAGE_SIZE)
 117 #endif
 118
 119 char debug_buf[DEBUG_BUF_SIZE];
 120 char *debug_buf_ptr = debug_buf;
 121 unsigned int debug_buf_size = sizeof(debug_buf);
 122
 123 static char model_name[64];
 124 /* uuid_string_t */ char kernel_uuid[37];
 125
 126 struct pasc {
 127   unsigned a: 7;
 128   unsigned b: 7;
 129   unsigned c: 7;
 130   unsigned d: 7;
 131   unsigned e: 7;
 132   unsigned f: 7;
 133   unsigned g: 7;
 134   unsigned h: 7;
 135 }  __attribute__((packed));
 136
 137 typedef struct pasc pasc_t;
 138
 139 /* Prevent CPP from breaking the definition below */
 140 #if CONFIG_NO_PANIC_STRINGS
 141 #undef Assert
 142 #endif
 143
 144 void
 145 Assert(
 146         const char      *file,
 147         int             line,
 148         const char      *expression
 149       )
 150 {
 151         int saved_return_on_panic;
 152
 153         if (!mach_assert) {
 154                 return;
 155         }
 156
 157         saved_return_on_panic = return_on_panic;
 158         return_on_panic = 1;
 159
 160         panic_plain("%s:%d Assertion failed: %s", file, line, expression);
 161
 162         return_on_panic = saved_return_on_panic;
 163 }
 164
 165 /*
 166  *      Carefully use the panic_lock.  There's always a chance that
 167  *      somehow we'll call panic before getting to initialize the
 168  *      panic_lock -- in this case, we'll assume that the world is
 169  *      in uniprocessor mode and just avoid using the panic lock.
 170  */
 171 #define PANIC_LOCK()                                                    \
 172 MACRO_BEGIN                                                             \
 173         if (panic_is_inited)                                            \
 174                 simple_lock(&panic_lock);                               \
 175 MACRO_END
 176
 177 #define PANIC_UNLOCK()                                                  \
 178 MACRO_BEGIN                                                             \
 179         if (panic_is_inited)                                            \
 180                 simple_unlock(&panic_lock);                             \
 181 MACRO_END
 182
 183
 184 void
 185 panic_init(void)
 186 {
 187         unsigned long uuidlen = 0;
 188         void *uuid;
 189
 190         uuid = getuuidfromheader(&_mh_execute_header, &uuidlen);
 191         if ((uuid != NULL) && (uuidlen == sizeof(uuid_t))) {
 192                 uuid_unparse_upper(*(uuid_t *)uuid, kernel_uuid);
 193         }
 194
 195         simple_lock_init(&panic_lock, 0);
 196         panic_is_inited = 1;
 197         panic_caller = 0;
 198 }
 199
 200 void
 201 debug_log_init(void)
 202 {
 203         if (debug_buf_size != 0)
 204                 return;
 205         debug_buf_ptr = debug_buf;
 206         debug_buf_size = sizeof(debug_buf);
 207 }
 208
 209 #if defined(__i386__) || defined(__x86_64__)
 210 #define panic_stop()    pmCPUHalt(PM_HALT_PANIC)
 211 #define panic_safe()    pmSafeMode(x86_lcpu(), PM_SAFE_FL_SAFE)
 212 #define panic_normal()  pmSafeMode(x86_lcpu(), PM_SAFE_FL_NORMAL)
 213 #else
 214 #define panic_stop()    { while (1) ; }
 215 #define panic_safe()
 216 #define panic_normal()
 217 #endif
 218
 219 /*
 220  * Prevent CPP from breaking the definition below,
 221  * since all clients get a #define to prepend line numbers
 222  */
 223 #undef panic
 224
 225 void _consume_panic_args(int a __unused, ...)
 226 {
 227     panic("panic");
 228 }
 229
 230 void
 231 panic(const char *str, ...)
 232 {
 233         va_list listp;
 234         spl_t   s;
 235         thread_t thread;
 236         wait_queue_t wq;
 237
 238 #if     defined(__i386__) || defined(__x86_64__)
 239         /* Attempt to display the unparsed panic string */
 240         const char *tstr = str;
 241
 242         kprintf("Panic initiated, string: ");
 243         while (tstr && *tstr)
 244                 kprintf("%c", *tstr++);
 245         kprintf("\n");
 246 #endif
 247         if (kdebug_enable)
 248                 kdbg_dump_trace_to_file("/var/tmp/panic.trace");
 249
 250         s = splhigh();
 251         disable_preemption();
 252
 253         panic_safe();
 254
 255         thread = current_thread();              /* Get failing thread */
 256         wq = thread->wait_queue;                /* Save the old value */
 257         thread->wait_queue = NULL;              /* Clear the wait so we do not get double panics when we try locks */
 258
 259         if( logPanicDataToScreen )
 260                 disable_debug_output = FALSE;
 261
 262         debug_mode = TRUE;
 263
 264         /* panic_caller is initialized to 0.  If set, don't change it */
 265         if ( ! panic_caller )
 266                 panic_caller = (unsigned long)(char *)__builtin_return_address(0);
 267
 268 restart:
 269         PANIC_LOCK();
 270         if (panicstr) {
 271                 if (cpu_number() != paniccpu) {
 272                         PANIC_UNLOCK();
 273                         /*
 274                          * Wait until message has been printed to identify correct
 275                          * cpu that made the first panic.
 276                          */
 277                         while (panicwait)
 278                                 continue;
 279                         goto restart;
 280             } else {
 281                         nestedpanic +=1;
 282                         PANIC_UNLOCK();
 283                         Debugger("double panic");
 284                         printf("double panic:  We are hanging here...\n");
 285                         panic_stop();
 286                         /* NOTREACHED */
 287                 }
 288         }
 289         panicstr = str;
 290         paniccpu = cpu_number();
 291         panicwait = 1;
 292
 293         PANIC_UNLOCK();
 294         kdb_printf("panic(cpu %d caller 0x%lx): ", (unsigned) paniccpu, panic_caller);
 295         if (str) {
 296                 va_start(listp, str);
 297                 _doprnt(str, &listp, consdebug_putc, 0);
 298                 va_end(listp);
 299         }
 300         kdb_printf("\n");
 301
 302         /*
 303          * Release panicwait indicator so that other cpus may call Debugger().
 304          */
 305         panicwait = 0;
 306         Debugger("panic");
 307         /*
 308          * Release panicstr so that we can handle normally other panics.
 309          */
 310         PANIC_LOCK();
 311         panicstr = (char *)0;
 312         PANIC_UNLOCK();
 313         thread->wait_queue = wq;        /* Restore the wait queue */
 314
 315         if (return_on_panic) {
 316                 panic_normal();
 317                 enable_preemption();
 318                 splx(s);
 319                 return;
 320         }
 321
 322         kdb_printf("panic: We are hanging here...\n");
 323         panic_stop();
 324         /* NOTREACHED */
 325 }
 326
 327 void
 328 log(__unused int level, char *fmt, ...)
 329 {
 330         va_list listp;
 331
 332 #ifdef lint
 333         level++;
 334 #endif /* lint */
 335 #ifdef  MACH_BSD
 336         disable_preemption();
 337         va_start(listp, fmt);
 338         _doprnt(fmt, &listp, conslog_putc, 0);
 339         va_end(listp);
 340         enable_preemption();
 341 #endif
 342 }
 343
 344 void
 345 debug_putc(char c)
 346 {
 347         if ((debug_buf_size != 0) &&
 348                 ((debug_buf_ptr-debug_buf) < (int)debug_buf_size)) {
 349                 *debug_buf_ptr=c;
 350                 debug_buf_ptr++;
 351         }
 352 }
 353
 354 /* In-place packing routines -- inefficient, but they're called at most once.
 355  * Assumes "buflen" is a multiple of 8.
 356  */
 357
 358 int packA(char *inbuf, uint32_t length, uint32_t buflen)
 359 {
 360   unsigned int i, j = 0;
 361   pasc_t pack;
 362
 363   length = MIN(((length + 7) & ~7), buflen);
 364
 365   for (i = 0; i < length; i+=8)
 366     {
 367       pack.a = inbuf[i];
 368       pack.b = inbuf[i+1];
 369       pack.c = inbuf[i+2];
 370       pack.d = inbuf[i+3];
 371       pack.e = inbuf[i+4];
 372       pack.f = inbuf[i+5];
 373       pack.g = inbuf[i+6];
 374       pack.h = inbuf[i+7];
 375       bcopy ((char *) &pack, inbuf + j, 7);
 376       j += 7;
 377     }
 378   return j;
 379 }
 380
 381 void unpackA(char *inbuf, uint32_t length)
 382 {
 383         pasc_t packs;
 384         unsigned i = 0;
 385         length = (length * 8)/7;
 386
 387         while (i < length) {
 388           packs = *(pasc_t *)&inbuf[i];
 389           bcopy(&inbuf[i+7], &inbuf[i+8], MAX(0, (int) (length - i - 8)));
 390           inbuf[i++] = packs.a;
 391           inbuf[i++] = packs.b;
 392           inbuf[i++] = packs.c;
 393           inbuf[i++] = packs.d;
 394           inbuf[i++] = packs.e;
 395           inbuf[i++] = packs.f;
 396           inbuf[i++] = packs.g;
 397           inbuf[i++] = packs.h;
 398         }
 399 }
 400
 401 extern void *proc_name_address(void *p);
 402
 403 static void
 404 panic_display_process_name(void) {
 405         char proc_name[32] = "Unknown";
 406         task_t ctask = 0;
 407         void *cbsd_info = 0;
 408
 409         if (ml_nofault_copy((vm_offset_t)&current_thread()->task, (vm_offset_t) &ctask, sizeof(task_t)) == sizeof(task_t))
 410                 if(ml_nofault_copy((vm_offset_t)&ctask->bsd_info, (vm_offset_t)&cbsd_info, sizeof(&ctask->bsd_info)) == sizeof(&ctask->bsd_info))
 411                         if (cbsd_info && (ml_nofault_copy((vm_offset_t) proc_name_address(cbsd_info), (vm_offset_t) &proc_name, sizeof(proc_name)) > 0))
 412                                 proc_name[sizeof(proc_name) - 1] = '\0';
 413         kdb_printf("\nBSD process name corresponding to current thread: %s\n", proc_name);
 414 }
 415
 416 unsigned        panic_active(void) {
 417         return ((panicstr != (char *) 0));
 418 }
 419
 420 void populate_model_name(char *model_string) {
 421         strlcpy(model_name, model_string, sizeof(model_name));
 422 }
 423
 424 static void panic_display_model_name(void) {
 425         char tmp_model_name[sizeof(model_name)];
 426
 427         if (ml_nofault_copy((vm_offset_t) &model_name, (vm_offset_t) &tmp_model_name, sizeof(model_name)) != sizeof(model_name))
 428                 return;
 429
 430         tmp_model_name[sizeof(tmp_model_name) - 1] = '\0';
 431
 432         if (tmp_model_name[0] != 0)
 433                 kdb_printf("System model name: %s\n", tmp_model_name);
 434 }
 435
 436 static void panic_display_kernel_uuid(void) {
 437         char tmp_kernel_uuid[sizeof(kernel_uuid)];
 438
 439         if (ml_nofault_copy((vm_offset_t) &kernel_uuid, (vm_offset_t) &tmp_kernel_uuid, sizeof(kernel_uuid)) != sizeof(kernel_uuid))
 440                 return;
 441
 442         if (tmp_kernel_uuid[0] != '\0')
 443                 kdb_printf("Kernel UUID: %s\n", tmp_kernel_uuid);
 444 }
 445
 446 static void panic_display_uptime(void) {
 447         uint64_t        uptime;
 448         absolutetime_to_nanoseconds(mach_absolute_time(), &uptime);
 449
 450         kdb_printf("\nSystem uptime in nanoseconds: %llu\n", uptime);
 451 }
 452
 453 extern const char version[];
 454 extern char osversion[];
 455
 456 static volatile uint32_t config_displayed = 0;
 457
 458 __private_extern__ void panic_display_system_configuration(void) {
 459
 460         panic_display_process_name();
 461         if (OSCompareAndSwap(0, 1, &config_displayed)) {
 462                 char buf[256];
 463                 if (strlcpy(buf, PE_boot_args(), sizeof(buf)))
 464                         kdb_printf("Boot args: %s\n", buf);
 465                 kdb_printf("\nMac OS version:\n%s\n",
 466                     (osversion[0] != 0) ? osversion : "Not yet set");
 467                 kdb_printf("\nKernel version:\n%s\n",version);
 468                 panic_display_kernel_uuid();
 469                 panic_display_pal_info();
 470                 panic_display_model_name();
 471                 panic_display_uptime();
 472                 panic_display_zprint();
 473 #if CONFIG_ZLEAKS
 474                 panic_display_ztrace();
 475 #endif /* CONFIG_ZLEAKS */
 476                 kext_dump_panic_lists(&kdb_log);
 477         }
 478 }
 479
 480 extern zone_t           first_zone;
 481 extern unsigned int     num_zones, stack_total;
 482 extern unsigned long long stack_allocs;
 483
 484 #if defined(__i386__) || defined (__x86_64__)
 485 extern unsigned int     inuse_ptepages_count;
 486 extern long long alloc_ptepages_count;
 487 #endif
 488
 489 extern boolean_t        panic_include_zprint;
 490
 491 __private_extern__ void panic_display_zprint()
 492 {
 493         if(panic_include_zprint == TRUE) {
 494
 495                 unsigned int    i;
 496                 struct zone     zone_copy;
 497
 498                 if(first_zone!=NULL) {
 499                         if(ml_nofault_copy((vm_offset_t)first_zone, (vm_offset_t)&zone_copy, sizeof(struct zone)) == sizeof(struct zone)) {
 500                                 for (i = 0; i < num_zones; i++) {
 501                                         if(zone_copy.cur_size > (1024*1024)) {
 502                                                 kdb_printf("%.20s:%lu\n",zone_copy.zone_name,(uintptr_t)zone_copy.cur_size);
 503                                         }
 504
 505                                         if(zone_copy.next_zone == NULL) {
 506                                                 break;
 507                                         }
 508
 509                                         if(ml_nofault_copy((vm_offset_t)zone_copy.next_zone, (vm_offset_t)&zone_copy, sizeof(struct zone)) != sizeof(struct zone)) {
 510                                                 break;
 511                                         }
 512                                 }
 513                         }
 514                 }
 515
 516                 kdb_printf("Kernel Stacks:%lu\n",(uintptr_t)(kernel_stack_size * stack_total));
 517
 518 #if defined(__i386__) || defined (__x86_64__)
 519                 kdb_printf("PageTables:%lu\n",(uintptr_t)(PAGE_SIZE * inuse_ptepages_count));
 520 #endif
 521
 522                 kdb_printf("Kalloc.Large:%lu\n",(uintptr_t)kalloc_large_total);
 523         }
 524 }
 525
 526 #if CONFIG_ZLEAKS
 527 extern boolean_t        panic_include_ztrace;
 528 extern struct ztrace* top_ztrace;
 529 /*
 530  * Prints the backtrace most suspected of being a leaker, if we paniced in the zone allocator.
 531  * top_ztrace and panic_include_ztrace comes from osfmk/kern/zalloc.c
 532  */
 533 __private_extern__ void panic_display_ztrace(void)
 534 {
 535         if(panic_include_ztrace == TRUE) {
 536                 unsigned int i = 0;
 537                 struct ztrace top_ztrace_copy;
 538
 539                 /* Make sure not to trip another panic if there's something wrong with memory */
 540                 if(ml_nofault_copy((vm_offset_t)top_ztrace, (vm_offset_t)&top_ztrace_copy, sizeof(struct ztrace)) == sizeof(struct ztrace)) {
 541                         kdb_printf("\nBacktrace suspected of leaking: (outstanding bytes: %lu)\n", (uintptr_t)top_ztrace_copy.zt_size);
 542                         /* Print the backtrace addresses */
 543                         for (i = 0; (i < top_ztrace_copy.zt_depth && i < MAX_ZTRACE_DEPTH) ; i++) {
 544                                 kdb_printf("%p\n", top_ztrace_copy.zt_stack[i]);
 545                         }
 546                         /* Print any kexts in that backtrace, along with their link addresses so we can properly blame them */
 547                         kmod_panic_dump((vm_offset_t *)&top_ztrace_copy.zt_stack[0], top_ztrace_copy.zt_depth);
 548                 }
 549                 else {
 550                         kdb_printf("\nCan't access top_ztrace...\n");
 551                 }
 552                 kdb_printf("\n");
 553         }
 554 }
 555 #endif /* CONFIG_ZLEAKS */
 556
 557 #if !MACH_KDP
 558 static struct ether_addr kdp_current_mac_address = {{0, 0, 0, 0, 0, 0}};
 559
 560 /* XXX ugly forward declares to stop warnings */
 561 void *kdp_get_interface(void);
 562 void kdp_set_ip_and_mac_addresses(struct in_addr *, struct ether_addr *);
 563 void kdp_set_gateway_mac(void *);
 564 void kdp_set_interface(void *);
 565 void kdp_register_send_receive(void *, void *);
 566 void kdp_unregister_send_receive(void *, void *);
 567 void kdp_snapshot_preflight(int, void *, uint32_t, uint32_t);
 568 int kdp_stack_snapshot_geterror(void);
 569 int kdp_stack_snapshot_bytes_traced(void);
 570
 571 void *
 572 kdp_get_interface( void)
 573 {
 574         return(void *)0;
 575 }
 576
 577 unsigned int
 578 kdp_get_ip_address(void )
 579 { return 0; }
 580
 581 struct ether_addr
 582 kdp_get_mac_addr(void)
 583 {
 584         return kdp_current_mac_address;
 585 }
 586
 587 void
 588 kdp_set_ip_and_mac_addresses(
 589         __unused struct in_addr          *ipaddr,
 590         __unused struct ether_addr       *macaddr)
 591 {}
 592
 593 void
 594 kdp_set_gateway_mac(__unused void *gatewaymac)
 595 {}
 596
 597 void
 598 kdp_set_interface(__unused void *ifp)
 599 {}
 600
 601 void
 602 kdp_register_send_receive(__unused void *send, __unused void *receive)
 603 {}
 604
 605 void
 606 kdp_unregister_send_receive(__unused void *send, __unused void *receive)
 607 {}
 608
 609 void
 610 kdp_snapshot_preflight(__unused int pid, __unused void * tracebuf,
 611                 __unused uint32_t tracebuf_size, __unused uint32_t options)
 612 {}
 613
 614 int
 615 kdp_stack_snapshot_geterror(void)
 616 {
 617         return -1;
 618 }
 619
 620 int
 621 kdp_stack_snapshot_bytes_traced(void)
 622 {
 623         return 0;
 624 }
 625
 626 #endif