osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50
  51 #include <mach_assert.h>
  52 #include <mach_kdb.h>
  53 #include <mach_kgdb.h>
  54 #include <mach_kdp.h>
  55
  56 #include <kern/cpu_number.h>
  57 #include <kern/lock.h>
  58 #include <kern/spl.h>
  59 #include <kern/thread.h>
  60 #include <kern/assert.h>
  61 #include <kern/sched_prim.h>
  62 #include <kern/misc_protos.h>
  63 #include <vm/vm_kern.h>
  64 #include <vm/pmap.h>
  65 #include <stdarg.h>
  66
  67 #ifdef  __ppc__
  68 #include <ppc/Firmware.h>
  69 #include <ppc/low_trace.h>
  70 #endif
  71
  72 unsigned int    halt_in_debugger = 0;
  73 unsigned int    switch_debugger = 0;
  74 unsigned int    current_debugger = 0;
  75 unsigned int    active_debugger = 0;
  76 unsigned int    debug_mode=0;
  77 unsigned int    disableDebugOuput = TRUE;
  78 unsigned int    systemLogDiags = FALSE;
  79 unsigned int    logPanicDataToScreen = FALSE;
  80 unsigned int    panicDebugging = FALSE;
  81
  82 int mach_assert = 1;
  83
  84 const char              *panicstr = (char *) 0;
  85 decl_simple_lock_data(,panic_lock)
  86 int                     paniccpu;
  87 volatile int            panicwait;
  88 volatile unsigned int   nestedpanic= 0;
  89 unsigned int            panic_is_inited = 0;
  90 unsigned int            return_on_panic = 0;
  91 unsigned long           panic_caller;
  92
  93 char *debug_buf;
  94 ppnum_t debug_buf_page;
  95 char *debug_buf_ptr;
  96 unsigned int debug_buf_size = 0;
  97
  98 void
  99 Assert(
 100         const char      *file,
 101         int             line,
 102         const char      *expression)
 103 {
 104         if (!mach_assert) {
 105                 return;
 106         }
 107         panic("{%d} Assertion failed: file \"%s\", line %d: %s\n",
 108                cpu_number(), file, line, expression);
 109 }
 110
 111 /*
 112  *      Carefully use the panic_lock.  There's always a chance that
 113  *      somehow we'll call panic before getting to initialize the
 114  *      panic_lock -- in this case, we'll assume that the world is
 115  *      in uniprocessor mode and just avoid using the panic lock.
 116  */
 117 #define PANIC_LOCK()                                                    \
 118 MACRO_BEGIN                                                             \
 119         if (panic_is_inited)                                            \
 120                 simple_lock(&panic_lock);                               \
 121 MACRO_END
 122
 123 #define PANIC_UNLOCK()                                                  \
 124 MACRO_BEGIN                                                             \
 125         if (panic_is_inited)                                            \
 126                 simple_unlock(&panic_lock);                             \
 127 MACRO_END
 128
 129
 130 void
 131 panic_init(void)
 132 {
 133         simple_lock_init(&panic_lock, 0);
 134         panic_is_inited = 1;
 135         panic_caller = 0;
 136 }
 137
 138 void
 139 panic(const char *str, ...)
 140 {
 141         va_list listp;
 142         spl_t   s;
 143         thread_t thread;
 144         wait_queue_t wq;
 145
 146         s = splhigh();
 147         disable_preemption();
 148
 149 #ifdef  __ppc__
 150         lastTrace = LLTraceSet(0);              /* Disable low-level tracing */
 151 #endif
 152
 153         thread = current_thread();              /* Get failing thread */
 154         wq = thread->wait_queue;                /* Save the old value */
 155         thread->wait_queue = 0;                 /* Clear the wait so we do not get double panics when we try locks */
 156
 157         if( logPanicDataToScreen )
 158                 disableDebugOuput = FALSE;
 159
 160         debug_mode = TRUE;
 161
 162         /* panic_caller is initialized to 0.  If set, don't change it */
 163         if ( ! panic_caller )
 164                 panic_caller = (unsigned long) __builtin_return_address(0);
 165
 166 restart:
 167         PANIC_LOCK();
 168         if (panicstr) {
 169                 if (cpu_number() != paniccpu) {
 170                         PANIC_UNLOCK();
 171                         /*
 172                          * Wait until message has been printed to identify correct
 173                          * cpu that made the first panic.
 174                          */
 175                         while (panicwait)
 176                                 continue;
 177                         goto restart;
 178             } else {
 179                         nestedpanic +=1;
 180                         PANIC_UNLOCK();
 181                         Debugger("double panic");
 182                         printf("double panic:  We are hanging here...\n");
 183                         while(1);
 184                         /* NOTREACHED */
 185                 }
 186         }
 187         panicstr = str;
 188         paniccpu = cpu_number();
 189         panicwait = 1;
 190
 191         PANIC_UNLOCK();
 192         kdb_printf("panic(cpu %d caller 0x%08X): ", (unsigned) paniccpu, panic_caller);
 193         va_start(listp, str);
 194         _doprnt(str, &listp, consdebug_putc, 0);
 195         va_end(listp);
 196         kdb_printf("\n");
 197
 198         /*
 199          * Release panicwait indicator so that other cpus may call Debugger().
 200          */
 201         panicwait = 0;
 202         Debugger("panic");
 203         /*
 204          * Release panicstr so that we can handle normally other panics.
 205          */
 206         PANIC_LOCK();
 207         panicstr = (char *)0;
 208         PANIC_UNLOCK();
 209         thread->wait_queue = wq;        /* Restore the wait queue */
 210         if (return_on_panic) {
 211                 enable_preemption();
 212                 splx(s);
 213                 return;
 214         }
 215         kdb_printf("panic: We are hanging here...\n");
 216         while(1);
 217         /* NOTREACHED */
 218 }
 219
 220 void
 221 log(int level, char *fmt, ...)
 222 {
 223         va_list listp;
 224
 225 #ifdef lint
 226         level++;
 227 #endif /* lint */
 228 #ifdef  MACH_BSD
 229         disable_preemption();
 230         va_start(listp, fmt);
 231         _doprnt(fmt, &listp, conslog_putc, 0);
 232         va_end(listp);
 233         enable_preemption();
 234 #endif
 235 }
 236
 237 void
 238 debug_log_init(void)
 239 {
 240         if (debug_buf_size != 0)
 241                 return;
 242         if (kmem_alloc(kernel_map, (vm_offset_t *) &debug_buf, PAGE_SIZE) != KERN_SUCCESS)
 243                 panic("cannot allocate debug_buf \n");
 244         debug_buf_ptr = debug_buf;
 245         debug_buf_size = PAGE_SIZE;
 246         debug_buf_page = pmap_find_phys(kernel_pmap, (addr64_t)(uintptr_t)debug_buf_ptr);
 247 }
 248
 249 void
 250 debug_putc(char c)
 251 {
 252         if ((debug_buf_size != 0) && ((debug_buf_ptr-debug_buf) < debug_buf_size)) {
 253                 *debug_buf_ptr=c;
 254                 debug_buf_ptr++;
 255         }
 256 }