osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * @OSF_COPYRIGHT@
  32  */
  33 /*
  34  * Mach Operating System
  35  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  36  * All Rights Reserved.
  37  *
  38  * Permission to use, copy, modify and distribute this software and its
  39  * documentation is hereby granted, provided that both the copyright
  40  * notice and this permission notice appear in all copies of the
  41  * software, derivative works or modified versions, and any portions
  42  * thereof, and that both notices appear in supporting documentation.
  43  *
  44  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  45  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  46  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  47  *
  48  * Carnegie Mellon requests users of this software to return to
  49  *
  50  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  51  *  School of Computer Science
  52  *  Carnegie Mellon University
  53  *  Pittsburgh PA 15213-3890
  54  *
  55  * any improvements or extensions that they make and grant Carnegie Mellon
  56  * the rights to redistribute these changes.
  57  */
  58
  59 #include <mach_assert.h>
  60 #include <mach_kdb.h>
  61 #include <mach_kgdb.h>
  62 #include <mach_kdp.h>
  63
  64 #include <kern/cpu_number.h>
  65 #include <kern/lock.h>
  66 #include <kern/spl.h>
  67 #include <kern/thread.h>
  68 #include <kern/assert.h>
  69 #include <kern/sched_prim.h>
  70 #include <kern/misc_protos.h>
  71 #include <vm/vm_kern.h>
  72 #include <vm/pmap.h>
  73 #include <stdarg.h>
  74
  75 #ifdef  __ppc__
  76 #include <ppc/Firmware.h>
  77 #include <ppc/low_trace.h>
  78 #endif
  79
  80 unsigned int    halt_in_debugger = 0;
  81 unsigned int    switch_debugger = 0;
  82 unsigned int    current_debugger = 0;
  83 unsigned int    active_debugger = 0;
  84 unsigned int    debug_mode=0;
  85 unsigned int    disableDebugOuput = TRUE;
  86 unsigned int    systemLogDiags = FALSE;
  87 unsigned int    logPanicDataToScreen = FALSE;
  88 unsigned int    panicDebugging = FALSE;
  89
  90 int mach_assert = 1;
  91
  92 const char              *panicstr = (char *) 0;
  93 decl_simple_lock_data(,panic_lock)
  94 int                     paniccpu;
  95 volatile int            panicwait;
  96 volatile unsigned int   nestedpanic= 0;
  97 unsigned int            panic_is_inited = 0;
  98 unsigned int            return_on_panic = 0;
  99 unsigned long           panic_caller;
 100
 101 char *debug_buf;
 102 ppnum_t debug_buf_page;
 103 char *debug_buf_ptr;
 104 unsigned int debug_buf_size = 0;
 105
 106 void
 107 Assert(
 108         const char      *file,
 109         int             line,
 110         const char      *expression)
 111 {
 112         if (!mach_assert) {
 113                 return;
 114         }
 115         panic("{%d} Assertion failed: file \"%s\", line %d: %s\n",
 116                cpu_number(), file, line, expression);
 117 }
 118
 119 /*
 120  *      Carefully use the panic_lock.  There's always a chance that
 121  *      somehow we'll call panic before getting to initialize the
 122  *      panic_lock -- in this case, we'll assume that the world is
 123  *      in uniprocessor mode and just avoid using the panic lock.
 124  */
 125 #define PANIC_LOCK()                                                    \
 126 MACRO_BEGIN                                                             \
 127         if (panic_is_inited)                                            \
 128                 simple_lock(&panic_lock);                               \
 129 MACRO_END
 130
 131 #define PANIC_UNLOCK()                                                  \
 132 MACRO_BEGIN                                                             \
 133         if (panic_is_inited)                                            \
 134                 simple_unlock(&panic_lock);                             \
 135 MACRO_END
 136
 137
 138 void
 139 panic_init(void)
 140 {
 141         simple_lock_init(&panic_lock, 0);
 142         panic_is_inited = 1;
 143         panic_caller = 0;
 144 }
 145
 146 void
 147 panic(const char *str, ...)
 148 {
 149         va_list listp;
 150         spl_t   s;
 151         thread_t thread;
 152         wait_queue_t wq;
 153
 154         s = splhigh();
 155         disable_preemption();
 156
 157 #ifdef  __ppc__
 158         lastTrace = LLTraceSet(0);              /* Disable low-level tracing */
 159 #endif
 160
 161         thread = current_thread();              /* Get failing thread */
 162         wq = thread->wait_queue;                /* Save the old value */
 163         thread->wait_queue = 0;                 /* Clear the wait so we do not get double panics when we try locks */
 164
 165         if( logPanicDataToScreen )
 166                 disableDebugOuput = FALSE;
 167
 168         debug_mode = TRUE;
 169
 170         /* panic_caller is initialized to 0.  If set, don't change it */
 171         if ( ! panic_caller )
 172                 panic_caller = (unsigned long) __builtin_return_address(0);
 173
 174 restart:
 175         PANIC_LOCK();
 176         if (panicstr) {
 177                 if (cpu_number() != paniccpu) {
 178                         PANIC_UNLOCK();
 179                         /*
 180                          * Wait until message has been printed to identify correct
 181                          * cpu that made the first panic.
 182                          */
 183                         while (panicwait)
 184                                 continue;
 185                         goto restart;
 186             } else {
 187                         nestedpanic +=1;
 188                         PANIC_UNLOCK();
 189                         Debugger("double panic");
 190                         printf("double panic:  We are hanging here...\n");
 191                         while(1);
 192                         /* NOTREACHED */
 193                 }
 194         }
 195         panicstr = str;
 196         paniccpu = cpu_number();
 197         panicwait = 1;
 198
 199         PANIC_UNLOCK();
 200         kdb_printf("panic(cpu %d caller 0x%08X): ", (unsigned) paniccpu, panic_caller);
 201         va_start(listp, str);
 202         _doprnt(str, &listp, consdebug_putc, 0);
 203         va_end(listp);
 204         kdb_printf("\n");
 205
 206         /*
 207          * Release panicwait indicator so that other cpus may call Debugger().
 208          */
 209         panicwait = 0;
 210         Debugger("panic");
 211         /*
 212          * Release panicstr so that we can handle normally other panics.
 213          */
 214         PANIC_LOCK();
 215         panicstr = (char *)0;
 216         PANIC_UNLOCK();
 217         thread->wait_queue = wq;        /* Restore the wait queue */
 218         if (return_on_panic) {
 219                 enable_preemption();
 220                 splx(s);
 221                 return;
 222         }
 223         kdb_printf("panic: We are hanging here...\n");
 224         while(1);
 225         /* NOTREACHED */
 226 }
 227
 228 void
 229 log(int level, char *fmt, ...)
 230 {
 231         va_list listp;
 232
 233 #ifdef lint
 234         level++;
 235 #endif /* lint */
 236 #ifdef  MACH_BSD
 237         disable_preemption();
 238         va_start(listp, fmt);
 239         _doprnt(fmt, &listp, conslog_putc, 0);
 240         va_end(listp);
 241         enable_preemption();
 242 #endif
 243 }
 244
 245 void
 246 debug_log_init(void)
 247 {
 248         if (debug_buf_size != 0)
 249                 return;
 250         if (kmem_alloc(kernel_map, (vm_offset_t *) &debug_buf, PAGE_SIZE) != KERN_SUCCESS)
 251                 panic("cannot allocate debug_buf \n");
 252         debug_buf_ptr = debug_buf;
 253         debug_buf_size = PAGE_SIZE;
 254         debug_buf_page = pmap_find_phys(kernel_pmap, (addr64_t)(uintptr_t)debug_buf_ptr);
 255 }
 256
 257 void
 258 debug_putc(char c)
 259 {
 260         if ((debug_buf_size != 0) && ((debug_buf_ptr-debug_buf) < debug_buf_size)) {
 261                 *debug_buf_ptr=c;
 262                 debug_buf_ptr++;
 263         }
 264 }