osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, 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/lock.h>
  64 #include <kern/spl.h>
  65 #include <kern/thread.h>
  66 #include <kern/assert.h>
  67 #include <kern/sched_prim.h>
  68 #include <kern/misc_protos.h>
  69 #include <vm/vm_kern.h>
  70 #include <vm/pmap.h>
  71 #include <stdarg.h>
  72
  73 #ifdef  __ppc__
  74 #include <ppc/Firmware.h>
  75 #include <ppc/low_trace.h>
  76 #endif
  77
  78 unsigned int    halt_in_debugger = 0;
  79 unsigned int    switch_debugger = 0;
  80 unsigned int    current_debugger = 0;
  81 unsigned int    active_debugger = 0;
  82 unsigned int    debug_mode=0;
  83 unsigned int    disableDebugOuput = TRUE;
  84 unsigned int    systemLogDiags = FALSE;
  85 unsigned int    logPanicDataToScreen = FALSE;
  86 unsigned int    panicDebugging = FALSE;
  87
  88 int mach_assert = 1;
  89
  90 const char              *panicstr = (char *) 0;
  91 decl_simple_lock_data(,panic_lock)
  92 int                     paniccpu;
  93 volatile int            panicwait;
  94 volatile unsigned int   nestedpanic= 0;
  95 unsigned int            panic_is_inited = 0;
  96 unsigned int            return_on_panic = 0;
  97 unsigned long           panic_caller;
  98
  99 char *debug_buf;
 100 ppnum_t debug_buf_page;
 101 char *debug_buf_ptr;
 102 unsigned int debug_buf_size = 0;
 103
 104 void
 105 Assert(
 106         const char      *file,
 107         int             line,
 108         const char      *expression)
 109 {
 110         if (!mach_assert) {
 111                 return;
 112         }
 113         panic("{%d} Assertion failed: file \"%s\", line %d: %s\n",
 114                cpu_number(), file, line, expression);
 115 }
 116
 117 /*
 118  *      Carefully use the panic_lock.  There's always a chance that
 119  *      somehow we'll call panic before getting to initialize the
 120  *      panic_lock -- in this case, we'll assume that the world is
 121  *      in uniprocessor mode and just avoid using the panic lock.
 122  */
 123 #define PANIC_LOCK()                                                    \
 124 MACRO_BEGIN                                                             \
 125         if (panic_is_inited)                                            \
 126                 simple_lock(&panic_lock);                               \
 127 MACRO_END
 128
 129 #define PANIC_UNLOCK()                                                  \
 130 MACRO_BEGIN                                                             \
 131         if (panic_is_inited)                                            \
 132                 simple_unlock(&panic_lock);                             \
 133 MACRO_END
 134
 135
 136 void
 137 panic_init(void)
 138 {
 139         simple_lock_init(&panic_lock, 0);
 140         panic_is_inited = 1;
 141         panic_caller = 0;
 142 }
 143
 144 void
 145 panic(const char *str, ...)
 146 {
 147         va_list listp;
 148         spl_t   s;
 149         thread_t thread;
 150         wait_queue_t wq;
 151
 152         s = splhigh();
 153         disable_preemption();
 154
 155 #ifdef  __ppc__
 156         lastTrace = LLTraceSet(0);              /* Disable low-level tracing */
 157 #endif
 158
 159         thread = current_thread();              /* Get failing thread */
 160         wq = thread->wait_queue;                /* Save the old value */
 161         thread->wait_queue = 0;                 /* Clear the wait so we do not get double panics when we try locks */
 162
 163         if( logPanicDataToScreen )
 164                 disableDebugOuput = FALSE;
 165
 166         debug_mode = TRUE;
 167
 168         /* panic_caller is initialized to 0.  If set, don't change it */
 169         if ( ! panic_caller )
 170                 panic_caller = (unsigned long) __builtin_return_address(0);
 171
 172 restart:
 173         PANIC_LOCK();
 174         if (panicstr) {
 175                 if (cpu_number() != paniccpu) {
 176                         PANIC_UNLOCK();
 177                         /*
 178                          * Wait until message has been printed to identify correct
 179                          * cpu that made the first panic.
 180                          */
 181                         while (panicwait)
 182                                 continue;
 183                         goto restart;
 184             } else {
 185                         nestedpanic +=1;
 186                         PANIC_UNLOCK();
 187                         Debugger("double panic");
 188                         printf("double panic:  We are hanging here...\n");
 189                         while(1);
 190                         /* NOTREACHED */
 191                 }
 192         }
 193         panicstr = str;
 194         paniccpu = cpu_number();
 195         panicwait = 1;
 196
 197         PANIC_UNLOCK();
 198         kdb_printf("panic(cpu %d caller 0x%08X): ", (unsigned) paniccpu, panic_caller);
 199         va_start(listp, str);
 200         _doprnt(str, &listp, consdebug_putc, 0);
 201         va_end(listp);
 202         kdb_printf("\n");
 203
 204         /*
 205          * Release panicwait indicator so that other cpus may call Debugger().
 206          */
 207         panicwait = 0;
 208         Debugger("panic");
 209         /*
 210          * Release panicstr so that we can handle normally other panics.
 211          */
 212         PANIC_LOCK();
 213         panicstr = (char *)0;
 214         PANIC_UNLOCK();
 215         thread->wait_queue = wq;        /* Restore the wait queue */
 216         if (return_on_panic) {
 217                 enable_preemption();
 218                 splx(s);
 219                 return;
 220         }
 221         kdb_printf("panic: We are hanging here...\n");
 222         while(1);
 223         /* NOTREACHED */
 224 }
 225
 226 void
 227 log(int level, char *fmt, ...)
 228 {
 229         va_list listp;
 230
 231 #ifdef lint
 232         level++;
 233 #endif /* lint */
 234 #ifdef  MACH_BSD
 235         disable_preemption();
 236         va_start(listp, fmt);
 237         _doprnt(fmt, &listp, conslog_putc, 0);
 238         va_end(listp);
 239         enable_preemption();
 240 #endif
 241 }
 242
 243 void
 244 debug_log_init(void)
 245 {
 246         if (debug_buf_size != 0)
 247                 return;
 248         if (kmem_alloc(kernel_map, (vm_offset_t *) &debug_buf, PAGE_SIZE) != KERN_SUCCESS)
 249                 panic("cannot allocate debug_buf \n");
 250         debug_buf_ptr = debug_buf;
 251         debug_buf_size = PAGE_SIZE;
 252         debug_buf_page = pmap_find_phys(kernel_pmap, (addr64_t)(uintptr_t)debug_buf_ptr);
 253 }
 254
 255 void
 256 debug_putc(char c)
 257 {
 258         if ((debug_buf_size != 0) && ((debug_buf_ptr-debug_buf) < debug_buf_size)) {
 259                 *debug_buf_ptr=c;
 260                 debug_buf_ptr++;
 261         }
 262 }