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 (kdebug_enable) {
 239                 ml_set_interrupts_enabled(TRUE);
 240                 kdbg_dump_trace_to_file("/var/tmp/panic.trace");
 241         }
 242
 243         s = splhigh();
 244         disable_preemption();
 245
 246 #if     defined(__i386__) || defined(__x86_64__)
 247         /* Attempt to display the unparsed panic string */
 248         const char *tstr = str;
 249
 250         kprintf("Panic initiated, string: ");
 251         while (tstr && *tstr)
 252                 kprintf("%c", *tstr++);
 253         kprintf("\n");
 254 #endif
 255
 256         panic_safe();
 257
 258         thread = current_thread();              /* Get failing thread */
 259         wq = thread->wait_queue;                /* Save the old value */
 260         thread->wait_queue = NULL;              /* Clear the wait so we do not get double panics when we try locks */
 261
 262         if( logPanicDataToScreen )
 263                 disable_debug_output = FALSE;
 264
 265         debug_mode = TRUE;
 266
 267         /* panic_caller is initialized to 0.  If set, don't change it */
 268         if ( ! panic_caller )
 269                 panic_caller = (unsigned long)(char *)__builtin_return_address(0);
 270
 271 restart:
 272         PANIC_LOCK();
 273         if (panicstr) {
 274                 if (cpu_number() != paniccpu) {
 275                         PANIC_UNLOCK();
 276                         /*
 277                          * Wait until message has been printed to identify correct
 278                          * cpu that made the first panic.
 279                          */
 280                         while (panicwait)
 281                                 continue;
 282                         goto restart;
 283             } else {
 284                         nestedpanic +=1;
 285                         PANIC_UNLOCK();
 286                         Debugger("double panic");
 287                         printf("double panic:  We are hanging here...\n");
 288                         panic_stop();
 289                         /* NOTREACHED */
 290                 }
 291         }
 292         panicstr = str;
 293         paniccpu = cpu_number();
 294         panicwait = 1;
 295
 296         PANIC_UNLOCK();
 297         kdb_printf("panic(cpu %d caller 0x%lx): ", (unsigned) paniccpu, panic_caller);
 298         if (str) {
 299                 va_start(listp, str);
 300                 _doprnt(str, &listp, consdebug_putc, 0);
 301                 va_end(listp);
 302         }
 303         kdb_printf("\n");
 304
 305         /*
 306          * Release panicwait indicator so that other cpus may call Debugger().
 307          */
 308         panicwait = 0;
 309         Debugger("panic");
 310         /*
 311          * Release panicstr so that we can handle normally other panics.
 312          */
 313         PANIC_LOCK();
 314         panicstr = (char *)0;
 315         PANIC_UNLOCK();
 316         thread->wait_queue = wq;        /* Restore the wait queue */
 317
 318         if (return_on_panic) {
 319                 panic_normal();
 320                 enable_preemption();
 321                 splx(s);
 322                 return;
 323         }
 324
 325         kdb_printf("panic: We are hanging here...\n");
 326         panic_stop();
 327         /* NOTREACHED */
 328 }
 329
 330 void
 331 log(__unused int level, char *fmt, ...)
 332 {
 333         va_list listp;
 334
 335 #ifdef lint
 336         level++;
 337 #endif /* lint */
 338 #ifdef  MACH_BSD
 339         disable_preemption();
 340         va_start(listp, fmt);
 341         _doprnt(fmt, &listp, conslog_putc, 0);
 342         va_end(listp);
 343         enable_preemption();
 344 #endif
 345 }
 346
 347 void
 348 debug_putc(char c)
 349 {
 350         if ((debug_buf_size != 0) &&
 351                 ((debug_buf_ptr-debug_buf) < (int)debug_buf_size)) {
 352                 *debug_buf_ptr=c;
 353                 debug_buf_ptr++;
 354         }
 355 }
 356
 357 /* In-place packing routines -- inefficient, but they're called at most once.
 358  * Assumes "buflen" is a multiple of 8.
 359  */
 360
 361 int packA(char *inbuf, uint32_t length, uint32_t buflen)
 362 {
 363   unsigned int i, j = 0;
 364   pasc_t pack;
 365
 366   length = MIN(((length + 7) & ~7), buflen);
 367
 368   for (i = 0; i < length; i+=8)
 369     {
 370       pack.a = inbuf[i];
 371       pack.b = inbuf[i+1];
 372       pack.c = inbuf[i+2];
 373       pack.d = inbuf[i+3];
 374       pack.e = inbuf[i+4];
 375       pack.f = inbuf[i+5];
 376       pack.g = inbuf[i+6];
 377       pack.h = inbuf[i+7];
 378       bcopy ((char *) &pack, inbuf + j, 7);
 379       j += 7;
 380     }
 381   return j;
 382 }
 383
 384 void unpackA(char *inbuf, uint32_t length)
 385 {
 386         pasc_t packs;
 387         unsigned i = 0;
 388         length = (length * 8)/7;
 389
 390         while (i < length) {
 391           packs = *(pasc_t *)&inbuf[i];
 392           bcopy(&inbuf[i+7], &inbuf[i+8], MAX(0, (int) (length - i - 8)));
 393           inbuf[i++] = packs.a;
 394           inbuf[i++] = packs.b;
 395           inbuf[i++] = packs.c;
 396           inbuf[i++] = packs.d;
 397           inbuf[i++] = packs.e;
 398           inbuf[i++] = packs.f;
 399           inbuf[i++] = packs.g;
 400           inbuf[i++] = packs.h;
 401         }
 402 }
 403
 404 extern void *proc_name_address(void *p);
 405
 406 static void
 407 panic_display_process_name(void) {
 408         char proc_name[32] = "Unknown";
 409         task_t ctask = 0;
 410         void *cbsd_info = 0;
 411
 412         if (ml_nofault_copy((vm_offset_t)&current_thread()->task, (vm_offset_t) &ctask, sizeof(task_t)) == sizeof(task_t))
 413                 if(ml_nofault_copy((vm_offset_t)&ctask->bsd_info, (vm_offset_t)&cbsd_info, sizeof(&ctask->bsd_info)) == sizeof(&ctask->bsd_info))
 414                         if (cbsd_info && (ml_nofault_copy((vm_offset_t) proc_name_address(cbsd_info), (vm_offset_t) &proc_name, sizeof(proc_name)) > 0))
 415                                 proc_name[sizeof(proc_name) - 1] = '\0';
 416         kdb_printf("\nBSD process name corresponding to current thread: %s\n", proc_name);
 417 }
 418
 419 unsigned        panic_active(void) {
 420         return ((panicstr != (char *) 0));
 421 }
 422
 423 void populate_model_name(char *model_string) {
 424         strlcpy(model_name, model_string, sizeof(model_name));
 425 }
 426
 427 static void panic_display_model_name(void) {
 428         char tmp_model_name[sizeof(model_name)];
 429
 430         if (ml_nofault_copy((vm_offset_t) &model_name, (vm_offset_t) &tmp_model_name, sizeof(model_name)) != sizeof(model_name))
 431                 return;
 432
 433         tmp_model_name[sizeof(tmp_model_name) - 1] = '\0';
 434
 435         if (tmp_model_name[0] != 0)
 436                 kdb_printf("System model name: %s\n", tmp_model_name);
 437 }
 438
 439 static void panic_display_kernel_uuid(void) {
 440         char tmp_kernel_uuid[sizeof(kernel_uuid)];
 441
 442         if (ml_nofault_copy((vm_offset_t) &kernel_uuid, (vm_offset_t) &tmp_kernel_uuid, sizeof(kernel_uuid)) != sizeof(kernel_uuid))
 443                 return;
 444
 445         if (tmp_kernel_uuid[0] != '\0')
 446                 kdb_printf("Kernel UUID: %s\n", tmp_kernel_uuid);
 447 }
 448
 449 static void panic_display_uptime(void) {
 450         uint64_t        uptime;
 451         absolutetime_to_nanoseconds(mach_absolute_time(), &uptime);
 452
 453         kdb_printf("\nSystem uptime in nanoseconds: %llu\n", uptime);
 454 }
 455
 456 extern const char version[];
 457 extern char osversion[];
 458
 459 static volatile uint32_t config_displayed = 0;
 460
 461 __private_extern__ void panic_display_system_configuration(void) {
 462
 463         panic_display_process_name();
 464         if (OSCompareAndSwap(0, 1, &config_displayed)) {
 465                 char buf[256];
 466                 if (strlcpy(buf, PE_boot_args(), sizeof(buf)))
 467                         kdb_printf("Boot args: %s\n", buf);
 468                 kdb_printf("\nMac OS version:\n%s\n",
 469                     (osversion[0] != 0) ? osversion : "Not yet set");
 470                 kdb_printf("\nKernel version:\n%s\n",version);
 471                 panic_display_kernel_uuid();
 472                 panic_display_pal_info();
 473                 panic_display_model_name();
 474                 panic_display_uptime();
 475                 panic_display_zprint();
 476 #if CONFIG_ZLEAKS
 477                 panic_display_ztrace();
 478 #endif /* CONFIG_ZLEAKS */
 479                 kext_dump_panic_lists(&kdb_log);
 480         }
 481 }
 482
 483 extern zone_t           first_zone;
 484 extern unsigned int     num_zones, stack_total;
 485 extern unsigned long long stack_allocs;
 486
 487 #if defined(__i386__) || defined (__x86_64__)
 488 extern unsigned int     inuse_ptepages_count;
 489 extern long long alloc_ptepages_count;
 490 #endif
 491
 492 extern boolean_t        panic_include_zprint;
 493
 494 __private_extern__ void panic_display_zprint()
 495 {
 496         if(panic_include_zprint == TRUE) {
 497
 498                 unsigned int    i;
 499                 struct zone     zone_copy;
 500
 501                 if(first_zone!=NULL) {
 502                         if(ml_nofault_copy((vm_offset_t)first_zone, (vm_offset_t)&zone_copy, sizeof(struct zone)) == sizeof(struct zone)) {
 503                                 for (i = 0; i < num_zones; i++) {
 504                                         if(zone_copy.cur_size > (1024*1024)) {
 505                                                 kdb_printf("%.20s:%lu\n",zone_copy.zone_name,(uintptr_t)zone_copy.cur_size);
 506                                         }
 507
 508                                         if(zone_copy.next_zone == NULL) {
 509                                                 break;
 510                                         }
 511
 512                                         if(ml_nofault_copy((vm_offset_t)zone_copy.next_zone, (vm_offset_t)&zone_copy, sizeof(struct zone)) != sizeof(struct zone)) {
 513                                                 break;
 514                                         }
 515                                 }
 516                         }
 517                 }
 518
 519                 kdb_printf("Kernel Stacks:%lu\n",(uintptr_t)(kernel_stack_size * stack_total));
 520
 521 #if defined(__i386__) || defined (__x86_64__)
 522                 kdb_printf("PageTables:%lu\n",(uintptr_t)(PAGE_SIZE * inuse_ptepages_count));
 523 #endif
 524
 525                 kdb_printf("Kalloc.Large:%lu\n",(uintptr_t)kalloc_large_total);
 526         }
 527 }
 528
 529 #if CONFIG_ZLEAKS
 530 extern boolean_t        panic_include_ztrace;
 531 extern struct ztrace* top_ztrace;
 532 /*
 533  * Prints the backtrace most suspected of being a leaker, if we paniced in the zone allocator.
 534  * top_ztrace and panic_include_ztrace comes from osfmk/kern/zalloc.c
 535  */
 536 __private_extern__ void panic_display_ztrace(void)
 537 {
 538         if(panic_include_ztrace == TRUE) {
 539                 unsigned int i = 0;
 540                 struct ztrace top_ztrace_copy;
 541
 542                 /* Make sure not to trip another panic if there's something wrong with memory */
 543                 if(ml_nofault_copy((vm_offset_t)top_ztrace, (vm_offset_t)&top_ztrace_copy, sizeof(struct ztrace)) == sizeof(struct ztrace)) {
 544                         kdb_printf("\nBacktrace suspected of leaking: (outstanding bytes: %lu)\n", (uintptr_t)top_ztrace_copy.zt_size);
 545                         /* Print the backtrace addresses */
 546                         for (i = 0; (i < top_ztrace_copy.zt_depth && i < MAX_ZTRACE_DEPTH) ; i++) {
 547                                 kdb_printf("%p\n", top_ztrace_copy.zt_stack[i]);
 548                         }
 549                         /* Print any kexts in that backtrace, along with their link addresses so we can properly blame them */
 550                         kmod_panic_dump((vm_offset_t *)&top_ztrace_copy.zt_stack[0], top_ztrace_copy.zt_depth);
 551                 }
 552                 else {
 553                         kdb_printf("\nCan't access top_ztrace...\n");
 554                 }
 555                 kdb_printf("\n");
 556         }
 557 }
 558 #endif /* CONFIG_ZLEAKS */
 559
 560 #if !MACH_KDP
 561 static struct ether_addr kdp_current_mac_address = {{0, 0, 0, 0, 0, 0}};
 562
 563 /* XXX ugly forward declares to stop warnings */
 564 void *kdp_get_interface(void);
 565 void kdp_set_ip_and_mac_addresses(struct in_addr *, struct ether_addr *);
 566 void kdp_set_gateway_mac(void *);
 567 void kdp_set_interface(void *);
 568 void kdp_register_send_receive(void *, void *);
 569 void kdp_unregister_send_receive(void *, void *);
 570 void kdp_snapshot_preflight(int, void *, uint32_t, uint32_t);
 571 int kdp_stack_snapshot_geterror(void);
 572 int kdp_stack_snapshot_bytes_traced(void);
 573
 574 void *
 575 kdp_get_interface( void)
 576 {
 577         return(void *)0;
 578 }
 579
 580 unsigned int
 581 kdp_get_ip_address(void )
 582 { return 0; }
 583
 584 struct ether_addr
 585 kdp_get_mac_addr(void)
 586 {
 587         return kdp_current_mac_address;
 588 }
 589
 590 void
 591 kdp_set_ip_and_mac_addresses(
 592         __unused struct in_addr          *ipaddr,
 593         __unused struct ether_addr       *macaddr)
 594 {}
 595
 596 void
 597 kdp_set_gateway_mac(__unused void *gatewaymac)
 598 {}
 599
 600 void
 601 kdp_set_interface(__unused void *ifp)
 602 {}
 603
 604 void
 605 kdp_register_send_receive(__unused void *send, __unused void *receive)
 606 {}
 607
 608 void
 609 kdp_unregister_send_receive(__unused void *send, __unused void *receive)
 610 {}
 611
 612 void
 613 kdp_snapshot_preflight(__unused int pid, __unused void * tracebuf,
 614                 __unused uint32_t tracebuf_size, __unused uint32_t options)
 615 {}
 616
 617 int
 618 kdp_stack_snapshot_geterror(void)
 619 {
 620         return -1;
 621 }
 622
 623 int
 624 kdp_stack_snapshot_bytes_traced(void)
 625 {
 626         return 0;
 627 }
 628
 629 #endif