arch/m68knommu/kernel/traps.c

   1 /*
   2  *  linux/arch/m68knommu/kernel/traps.c
   3  *
   4  *  Copyright (C) 1993, 1994 by Hamish Macdonald
   5  *
   6  *  68040 fixes by Michael Rausch
   7  *  68040 fixes by Martin Apel
   8  *  68060 fixes by Roman Hodek
   9  *  68060 fixes by Jesper Skov
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file COPYING in the main directory of this archive
  13  * for more details.
  14  */
  15
  16 /*
  17  * Sets up all exception vectors
  18  */
  19 #include <linux/sched.h>
  20 #include <linux/signal.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/types.h>
  25 #include <linux/user.h>
  26 #include <linux/string.h>
  27 #include <linux/linkage.h>
  28 #include <linux/init.h>
  29 #include <linux/ptrace.h>
  30 #include <linux/kallsyms.h>
  31
  32 #include <asm/setup.h>
  33 #include <asm/fpu.h>
  34 #include <asm/system.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/traps.h>
  37 #include <asm/pgtable.h>
  38 #include <asm/machdep.h>
  39 #include <asm/siginfo.h>
  40
  41 static char const * const vec_names[] = {
  42         "RESET SP", "RESET PC", "BUS ERROR", "ADDRESS ERROR",
  43         "ILLEGAL INSTRUCTION", "ZERO DIVIDE", "CHK", "TRAPcc",
  44         "PRIVILEGE VIOLATION", "TRACE", "LINE 1010", "LINE 1111",
  45         "UNASSIGNED RESERVED 12", "COPROCESSOR PROTOCOL VIOLATION",
  46         "FORMAT ERROR", "UNINITIALIZED INTERRUPT",
  47         "UNASSIGNED RESERVED 16", "UNASSIGNED RESERVED 17",
  48         "UNASSIGNED RESERVED 18", "UNASSIGNED RESERVED 19",
  49         "UNASSIGNED RESERVED 20", "UNASSIGNED RESERVED 21",
  50         "UNASSIGNED RESERVED 22", "UNASSIGNED RESERVED 23",
  51         "SPURIOUS INTERRUPT", "LEVEL 1 INT", "LEVEL 2 INT", "LEVEL 3 INT",
  52         "LEVEL 4 INT", "LEVEL 5 INT", "LEVEL 6 INT", "LEVEL 7 INT",
  53         "SYSCALL", "TRAP #1", "TRAP #2", "TRAP #3",
  54         "TRAP #4", "TRAP #5", "TRAP #6", "TRAP #7",
  55         "TRAP #8", "TRAP #9", "TRAP #10", "TRAP #11",
  56         "TRAP #12", "TRAP #13", "TRAP #14", "TRAP #15",
  57         "FPCP BSUN", "FPCP INEXACT", "FPCP DIV BY 0", "FPCP UNDERFLOW",
  58         "FPCP OPERAND ERROR", "FPCP OVERFLOW", "FPCP SNAN",
  59         "FPCP UNSUPPORTED OPERATION",
  60         "MMU CONFIGURATION ERROR"
  61 };
  62
  63 void __init trap_init(void)
  64 {
  65 }
  66
  67 void die_if_kernel(char *str, struct pt_regs *fp, int nr)
  68 {
  69         if (!(fp->sr & PS_S))
  70                 return;
  71
  72         console_verbose();
  73         printk(KERN_EMERG "%s: %08x\n",str,nr);
  74         printk(KERN_EMERG "PC: [<%08lx>]\nSR: %04x  SP: %p  a2: %08lx\n",
  75                fp->pc, fp->sr, fp, fp->a2);
  76         printk(KERN_EMERG "d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
  77                fp->d0, fp->d1, fp->d2, fp->d3);
  78         printk(KERN_EMERG "d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
  79                fp->d4, fp->d5, fp->a0, fp->a1);
  80
  81         printk(KERN_EMERG "Process %s (pid: %d, stackpage=%08lx)\n",
  82                 current->comm, current->pid, PAGE_SIZE+(unsigned long)current);
  83         show_stack(NULL, (unsigned long *)(fp + 1));
  84         add_taint(TAINT_DIE);
  85         do_exit(SIGSEGV);
  86 }
  87
  88 asmlinkage void buserr_c(struct frame *fp)
  89 {
  90         /* Only set esp0 if coming from user mode */
  91         if (user_mode(&fp->ptregs))
  92                 current->thread.esp0 = (unsigned long) fp;
  93
  94 #if defined(DEBUG)
  95         printk (KERN_DEBUG "*** Bus Error *** Format is %x\n", fp->ptregs.format);
  96 #endif
  97
  98         die_if_kernel("bad frame format",&fp->ptregs,0);
  99 #if defined(DEBUG)
 100         printk(KERN_DEBUG "Unknown SIGSEGV - 4\n");
 101 #endif
 102         force_sig(SIGSEGV, current);
 103 }
 104
 105 static void print_this_address(unsigned long addr, int i)
 106 {
 107 #ifdef CONFIG_KALLSYMS
 108         printk(KERN_EMERG " [%08lx] ", addr);
 109         print_symbol(KERN_CONT "%s\n", addr);
 110 #else
 111         if (i % 5)
 112                 printk(KERN_CONT " [%08lx] ", addr);
 113         else
 114                 printk(KERN_CONT "\n" KERN_EMERG " [%08lx] ", addr);
 115         i++;
 116 #endif
 117 }
 118
 119 int kstack_depth_to_print = 48;
 120
 121 static void __show_stack(struct task_struct *task, unsigned long *stack)
 122 {
 123         unsigned long *endstack, addr;
 124 #ifdef CONFIG_FRAME_POINTER
 125         unsigned long *last_stack;
 126 #endif
 127         int i;
 128
 129         if (!stack)
 130                 stack = (unsigned long *)task->thread.ksp;
 131
 132         addr = (unsigned long) stack;
 133         endstack = (unsigned long *) PAGE_ALIGN(addr);
 134
 135         printk(KERN_EMERG "Stack from %08lx:", (unsigned long)stack);
 136         for (i = 0; i < kstack_depth_to_print; i++) {
 137                 if (stack + 1 + i > endstack)
 138                         break;
 139                 if (i % 8 == 0)
 140                         printk("\n" KERN_EMERG "       ");
 141                 printk(" %08lx", *(stack + i));
 142         }
 143         printk("\n");
 144         i = 0;
 145
 146 #ifdef CONFIG_FRAME_POINTER
 147         printk(KERN_EMERG "Call Trace:\n");
 148
 149         last_stack = stack - 1;
 150         while (stack <= endstack && stack > last_stack) {
 151
 152                 addr = *(stack + 1);
 153                 print_this_address(addr, i);
 154                 i++;
 155
 156                 last_stack = stack;
 157                 stack = (unsigned long *)*stack;
 158         }
 159         printk("\n");
 160 #else
 161         printk(KERN_EMERG "Call Trace with CONFIG_FRAME_POINTER disabled:\n");
 162         while (stack <= endstack) {
 163                 addr = *stack++;
 164                 /*
 165                  * If the address is either in the text segment of the kernel,
 166                  * or in a region which is occupied by a module then it *may*
 167                  * be the address of a calling routine; if so, print it so that
 168                  * someone tracing down the cause of the crash will be able to
 169                  * figure out the call path that was taken.
 170                  */
 171                 if (__kernel_text_address(addr)) {
 172                         print_this_address(addr, i);
 173                         i++;
 174                 }
 175         }
 176         printk(KERN_CONT "\n");
 177 #endif
 178 }
 179
 180 void bad_super_trap(struct frame *fp)
 181 {
 182         console_verbose();
 183         if (fp->ptregs.vector < 4 * ARRAY_SIZE(vec_names))
 184                 printk (KERN_WARNING "*** %s ***   FORMAT=%X\n",
 185                         vec_names[(fp->ptregs.vector) >> 2],
 186                         fp->ptregs.format);
 187         else
 188                 printk (KERN_WARNING "*** Exception %d ***   FORMAT=%X\n",
 189                         (fp->ptregs.vector) >> 2,
 190                         fp->ptregs.format);
 191         printk (KERN_WARNING "Current process id is %d\n", current->pid);
 192         die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
 193 }
 194
 195 asmlinkage void trap_c(struct frame *fp)
 196 {
 197         int sig;
 198         siginfo_t info;
 199
 200         if (fp->ptregs.sr & PS_S) {
 201                 if ((fp->ptregs.vector >> 2) == VEC_TRACE) {
 202                         /* traced a trapping instruction */
 203                 } else
 204                         bad_super_trap(fp);
 205                 return;
 206         }
 207
 208         /* send the appropriate signal to the user program */
 209         switch ((fp->ptregs.vector) >> 2) {
 210             case VEC_ADDRERR:
 211                 info.si_code = BUS_ADRALN;
 212                 sig = SIGBUS;
 213                 break;
 214             case VEC_ILLEGAL:
 215             case VEC_LINE10:
 216             case VEC_LINE11:
 217                 info.si_code = ILL_ILLOPC;
 218                 sig = SIGILL;
 219                 break;
 220             case VEC_PRIV:
 221                 info.si_code = ILL_PRVOPC;
 222                 sig = SIGILL;
 223                 break;
 224             case VEC_COPROC:
 225                 info.si_code = ILL_COPROC;
 226                 sig = SIGILL;
 227                 break;
 228             case VEC_TRAP1: /* gdbserver breakpoint */
 229                 fp->ptregs.pc -= 2;
 230                 info.si_code = TRAP_TRACE;
 231                 sig = SIGTRAP;
 232                 break;
 233             case VEC_TRAP2:
 234             case VEC_TRAP3:
 235             case VEC_TRAP4:
 236             case VEC_TRAP5:
 237             case VEC_TRAP6:
 238             case VEC_TRAP7:
 239             case VEC_TRAP8:
 240             case VEC_TRAP9:
 241             case VEC_TRAP10:
 242             case VEC_TRAP11:
 243             case VEC_TRAP12:
 244             case VEC_TRAP13:
 245             case VEC_TRAP14:
 246                 info.si_code = ILL_ILLTRP;
 247                 sig = SIGILL;
 248                 break;
 249             case VEC_FPBRUC:
 250             case VEC_FPOE:
 251             case VEC_FPNAN:
 252                 info.si_code = FPE_FLTINV;
 253                 sig = SIGFPE;
 254                 break;
 255             case VEC_FPIR:
 256                 info.si_code = FPE_FLTRES;
 257                 sig = SIGFPE;
 258                 break;
 259             case VEC_FPDIVZ:
 260                 info.si_code = FPE_FLTDIV;
 261                 sig = SIGFPE;
 262                 break;
 263             case VEC_FPUNDER:
 264                 info.si_code = FPE_FLTUND;
 265                 sig = SIGFPE;
 266                 break;
 267             case VEC_FPOVER:
 268                 info.si_code = FPE_FLTOVF;
 269                 sig = SIGFPE;
 270                 break;
 271             case VEC_ZERODIV:
 272                 info.si_code = FPE_INTDIV;
 273                 sig = SIGFPE;
 274                 break;
 275             case VEC_CHK:
 276             case VEC_TRAP:
 277                 info.si_code = FPE_INTOVF;
 278                 sig = SIGFPE;
 279                 break;
 280             case VEC_TRACE:             /* ptrace single step */
 281                 info.si_code = TRAP_TRACE;
 282                 sig = SIGTRAP;
 283                 break;
 284             case VEC_TRAP15:            /* breakpoint */
 285                 info.si_code = TRAP_BRKPT;
 286                 sig = SIGTRAP;
 287                 break;
 288             default:
 289                 info.si_code = ILL_ILLOPC;
 290                 sig = SIGILL;
 291                 break;
 292         }
 293         info.si_signo = sig;
 294         info.si_errno = 0;
 295         switch (fp->ptregs.format) {
 296             default:
 297                 info.si_addr = (void *) fp->ptregs.pc;
 298                 break;
 299             case 2:
 300                 info.si_addr = (void *) fp->un.fmt2.iaddr;
 301                 break;
 302             case 7:
 303                 info.si_addr = (void *) fp->un.fmt7.effaddr;
 304                 break;
 305             case 9:
 306                 info.si_addr = (void *) fp->un.fmt9.iaddr;
 307                 break;
 308             case 10:
 309                 info.si_addr = (void *) fp->un.fmta.daddr;
 310                 break;
 311             case 11:
 312                 info.si_addr = (void *) fp->un.fmtb.daddr;
 313                 break;
 314         }
 315         force_sig_info (sig, &info, current);
 316 }
 317
 318 asmlinkage void set_esp0(unsigned long ssp)
 319 {
 320         current->thread.esp0 = ssp;
 321 }
 322
 323 /*
 324  * The architecture-independent backtrace generator
 325  */
 326 void dump_stack(void)
 327 {
 328         /*
 329          * We need frame pointers for this little trick, which works as follows:
 330          *
 331          * +------------+ 0x00
 332          * | Next SP    |       -> 0x0c
 333          * +------------+ 0x04
 334          * | Caller     |
 335          * +------------+ 0x08
 336          * | Local vars |       -> our stack var
 337          * +------------+ 0x0c
 338          * | Next SP    |       -> 0x18, that is what we pass to show_stack()
 339          * +------------+ 0x10
 340          * | Caller     |
 341          * +------------+ 0x14
 342          * | Local vars |
 343          * +------------+ 0x18
 344          * | ...        |
 345          * +------------+
 346          */
 347
 348         unsigned long *stack;
 349
 350         stack = (unsigned long *)&stack;
 351         stack++;
 352         __show_stack(current, stack);
 353 }
 354 EXPORT_SYMBOL(dump_stack);
 355
 356 void show_stack(struct task_struct *task, unsigned long *stack)
 357 {
 358         if (!stack && !task)
 359                 dump_stack();
 360         else
 361                 __show_stack(task, stack);
 362 }
 363
 364 #ifdef CONFIG_M68KFPU_EMU
 365 asmlinkage void fpemu_signal(int signal, int code, void *addr)
 366 {
 367         siginfo_t info;
 368
 369         info.si_signo = signal;
 370         info.si_errno = 0;
 371         info.si_code = code;
 372         info.si_addr = addr;
 373         force_sig_info(signal, &info, current);
 374 }
 375 #endif