dump_stack: consolidate dump_stack() implementations and unify their behaviors
[linux-3.10.git] / arch / m68k / kernel / traps.c
1 /*
2  *  linux/arch/m68k/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  *  68040 fixes and writeback by Richard Zidlicky
9  *  68060 fixes by Roman Hodek
10  *  68060 fixes by Jesper Skov
11  *
12  * This file is subject to the terms and conditions of the GNU General Public
13  * License.  See the file COPYING in the main directory of this archive
14  * for more details.
15  */
16
17 /*
18  * Sets up all exception vectors
19  */
20
21 #include <linux/sched.h>
22 #include <linux/signal.h>
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/module.h>
26 #include <linux/user.h>
27 #include <linux/string.h>
28 #include <linux/linkage.h>
29 #include <linux/init.h>
30 #include <linux/ptrace.h>
31 #include <linux/kallsyms.h>
32
33 #include <asm/setup.h>
34 #include <asm/fpu.h>
35 #include <asm/uaccess.h>
36 #include <asm/traps.h>
37 #include <asm/pgalloc.h>
38 #include <asm/machdep.h>
39 #include <asm/siginfo.h>
40
41
42 static const char *vec_names[] = {
43         [VEC_RESETSP]   = "RESET SP",
44         [VEC_RESETPC]   = "RESET PC",
45         [VEC_BUSERR]    = "BUS ERROR",
46         [VEC_ADDRERR]   = "ADDRESS ERROR",
47         [VEC_ILLEGAL]   = "ILLEGAL INSTRUCTION",
48         [VEC_ZERODIV]   = "ZERO DIVIDE",
49         [VEC_CHK]       = "CHK",
50         [VEC_TRAP]      = "TRAPcc",
51         [VEC_PRIV]      = "PRIVILEGE VIOLATION",
52         [VEC_TRACE]     = "TRACE",
53         [VEC_LINE10]    = "LINE 1010",
54         [VEC_LINE11]    = "LINE 1111",
55         [VEC_RESV12]    = "UNASSIGNED RESERVED 12",
56         [VEC_COPROC]    = "COPROCESSOR PROTOCOL VIOLATION",
57         [VEC_FORMAT]    = "FORMAT ERROR",
58         [VEC_UNINT]     = "UNINITIALIZED INTERRUPT",
59         [VEC_RESV16]    = "UNASSIGNED RESERVED 16",
60         [VEC_RESV17]    = "UNASSIGNED RESERVED 17",
61         [VEC_RESV18]    = "UNASSIGNED RESERVED 18",
62         [VEC_RESV19]    = "UNASSIGNED RESERVED 19",
63         [VEC_RESV20]    = "UNASSIGNED RESERVED 20",
64         [VEC_RESV21]    = "UNASSIGNED RESERVED 21",
65         [VEC_RESV22]    = "UNASSIGNED RESERVED 22",
66         [VEC_RESV23]    = "UNASSIGNED RESERVED 23",
67         [VEC_SPUR]      = "SPURIOUS INTERRUPT",
68         [VEC_INT1]      = "LEVEL 1 INT",
69         [VEC_INT2]      = "LEVEL 2 INT",
70         [VEC_INT3]      = "LEVEL 3 INT",
71         [VEC_INT4]      = "LEVEL 4 INT",
72         [VEC_INT5]      = "LEVEL 5 INT",
73         [VEC_INT6]      = "LEVEL 6 INT",
74         [VEC_INT7]      = "LEVEL 7 INT",
75         [VEC_SYS]       = "SYSCALL",
76         [VEC_TRAP1]     = "TRAP #1",
77         [VEC_TRAP2]     = "TRAP #2",
78         [VEC_TRAP3]     = "TRAP #3",
79         [VEC_TRAP4]     = "TRAP #4",
80         [VEC_TRAP5]     = "TRAP #5",
81         [VEC_TRAP6]     = "TRAP #6",
82         [VEC_TRAP7]     = "TRAP #7",
83         [VEC_TRAP8]     = "TRAP #8",
84         [VEC_TRAP9]     = "TRAP #9",
85         [VEC_TRAP10]    = "TRAP #10",
86         [VEC_TRAP11]    = "TRAP #11",
87         [VEC_TRAP12]    = "TRAP #12",
88         [VEC_TRAP13]    = "TRAP #13",
89         [VEC_TRAP14]    = "TRAP #14",
90         [VEC_TRAP15]    = "TRAP #15",
91         [VEC_FPBRUC]    = "FPCP BSUN",
92         [VEC_FPIR]      = "FPCP INEXACT",
93         [VEC_FPDIVZ]    = "FPCP DIV BY 0",
94         [VEC_FPUNDER]   = "FPCP UNDERFLOW",
95         [VEC_FPOE]      = "FPCP OPERAND ERROR",
96         [VEC_FPOVER]    = "FPCP OVERFLOW",
97         [VEC_FPNAN]     = "FPCP SNAN",
98         [VEC_FPUNSUP]   = "FPCP UNSUPPORTED OPERATION",
99         [VEC_MMUCFG]    = "MMU CONFIGURATION ERROR",
100         [VEC_MMUILL]    = "MMU ILLEGAL OPERATION ERROR",
101         [VEC_MMUACC]    = "MMU ACCESS LEVEL VIOLATION ERROR",
102         [VEC_RESV59]    = "UNASSIGNED RESERVED 59",
103         [VEC_UNIMPEA]   = "UNASSIGNED RESERVED 60",
104         [VEC_UNIMPII]   = "UNASSIGNED RESERVED 61",
105         [VEC_RESV62]    = "UNASSIGNED RESERVED 62",
106         [VEC_RESV63]    = "UNASSIGNED RESERVED 63",
107 };
108
109 static const char *space_names[] = {
110         [0]             = "Space 0",
111         [USER_DATA]     = "User Data",
112         [USER_PROGRAM]  = "User Program",
113 #ifndef CONFIG_SUN3
114         [3]             = "Space 3",
115 #else
116         [FC_CONTROL]    = "Control",
117 #endif
118         [4]             = "Space 4",
119         [SUPER_DATA]    = "Super Data",
120         [SUPER_PROGRAM] = "Super Program",
121         [CPU_SPACE]     = "CPU"
122 };
123
124 void die_if_kernel(char *,struct pt_regs *,int);
125 asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
126                              unsigned long error_code);
127 int send_fault_sig(struct pt_regs *regs);
128
129 asmlinkage void trap_c(struct frame *fp);
130
131 #if defined (CONFIG_M68060)
132 static inline void access_error060 (struct frame *fp)
133 {
134         unsigned long fslw = fp->un.fmt4.pc; /* is really FSLW for access error */
135
136 #ifdef DEBUG
137         printk("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
138 #endif
139
140         if (fslw & MMU060_BPE) {
141                 /* branch prediction error -> clear branch cache */
142                 __asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
143                                       "orl   #0x00400000,%/d0\n\t"
144                                       "movec %/d0,%/cacr"
145                                       : : : "d0" );
146                 /* return if there's no other error */
147                 if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
148                         return;
149         }
150
151         if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
152                 unsigned long errorcode;
153                 unsigned long addr = fp->un.fmt4.effaddr;
154
155                 if (fslw & MMU060_MA)
156                         addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
157
158                 errorcode = 1;
159                 if (fslw & MMU060_DESC_ERR) {
160                         __flush_tlb040_one(addr);
161                         errorcode = 0;
162                 }
163                 if (fslw & MMU060_W)
164                         errorcode |= 2;
165 #ifdef DEBUG
166                 printk("errorcode = %d\n", errorcode );
167 #endif
168                 do_page_fault(&fp->ptregs, addr, errorcode);
169         } else if (fslw & (MMU060_SEE)){
170                 /* Software Emulation Error.
171                  * fault during mem_read/mem_write in ifpsp060/os.S
172                  */
173                 send_fault_sig(&fp->ptregs);
174         } else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
175                    send_fault_sig(&fp->ptregs) > 0) {
176                 printk("pc=%#lx, fa=%#lx\n", fp->ptregs.pc, fp->un.fmt4.effaddr);
177                 printk( "68060 access error, fslw=%lx\n", fslw );
178                 trap_c( fp );
179         }
180 }
181 #endif /* CONFIG_M68060 */
182
183 #if defined (CONFIG_M68040)
184 static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
185 {
186         unsigned long mmusr;
187         mm_segment_t old_fs = get_fs();
188
189         set_fs(MAKE_MM_SEG(wbs));
190
191         if (iswrite)
192                 asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
193         else
194                 asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
195
196         asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
197
198         set_fs(old_fs);
199
200         return mmusr;
201 }
202
203 static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
204                                    unsigned long wbd)
205 {
206         int res = 0;
207         mm_segment_t old_fs = get_fs();
208
209         /* set_fs can not be moved, otherwise put_user() may oops */
210         set_fs(MAKE_MM_SEG(wbs));
211
212         switch (wbs & WBSIZ_040) {
213         case BA_SIZE_BYTE:
214                 res = put_user(wbd & 0xff, (char __user *)wba);
215                 break;
216         case BA_SIZE_WORD:
217                 res = put_user(wbd & 0xffff, (short __user *)wba);
218                 break;
219         case BA_SIZE_LONG:
220                 res = put_user(wbd, (int __user *)wba);
221                 break;
222         }
223
224         /* set_fs can not be moved, otherwise put_user() may oops */
225         set_fs(old_fs);
226
227
228 #ifdef DEBUG
229         printk("do_040writeback1, res=%d\n",res);
230 #endif
231
232         return res;
233 }
234
235 /* after an exception in a writeback the stack frame corresponding
236  * to that exception is discarded, set a few bits in the old frame
237  * to simulate what it should look like
238  */
239 static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
240 {
241         fp->un.fmt7.faddr = wba;
242         fp->un.fmt7.ssw = wbs & 0xff;
243         if (wba != current->thread.faddr)
244             fp->un.fmt7.ssw |= MA_040;
245 }
246
247 static inline void do_040writebacks(struct frame *fp)
248 {
249         int res = 0;
250 #if 0
251         if (fp->un.fmt7.wb1s & WBV_040)
252                 printk("access_error040: cannot handle 1st writeback. oops.\n");
253 #endif
254
255         if ((fp->un.fmt7.wb2s & WBV_040) &&
256             !(fp->un.fmt7.wb2s & WBTT_040)) {
257                 res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
258                                        fp->un.fmt7.wb2d);
259                 if (res)
260                         fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
261                 else
262                         fp->un.fmt7.wb2s = 0;
263         }
264
265         /* do the 2nd wb only if the first one was successful (except for a kernel wb) */
266         if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
267                 res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
268                                        fp->un.fmt7.wb3d);
269                 if (res)
270                     {
271                         fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
272
273                         fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
274                         fp->un.fmt7.wb3s &= (~WBV_040);
275                         fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
276                         fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
277                     }
278                 else
279                         fp->un.fmt7.wb3s = 0;
280         }
281
282         if (res)
283                 send_fault_sig(&fp->ptregs);
284 }
285
286 /*
287  * called from sigreturn(), must ensure userspace code didn't
288  * manipulate exception frame to circumvent protection, then complete
289  * pending writebacks
290  * we just clear TM2 to turn it into a userspace access
291  */
292 asmlinkage void berr_040cleanup(struct frame *fp)
293 {
294         fp->un.fmt7.wb2s &= ~4;
295         fp->un.fmt7.wb3s &= ~4;
296
297         do_040writebacks(fp);
298 }
299
300 static inline void access_error040(struct frame *fp)
301 {
302         unsigned short ssw = fp->un.fmt7.ssw;
303         unsigned long mmusr;
304
305 #ifdef DEBUG
306         printk("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
307         printk("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
308                 fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
309         printk ("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
310                 fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
311                 fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
312 #endif
313
314         if (ssw & ATC_040) {
315                 unsigned long addr = fp->un.fmt7.faddr;
316                 unsigned long errorcode;
317
318                 /*
319                  * The MMU status has to be determined AFTER the address
320                  * has been corrected if there was a misaligned access (MA).
321                  */
322                 if (ssw & MA_040)
323                         addr = (addr + 7) & -8;
324
325                 /* MMU error, get the MMUSR info for this access */
326                 mmusr = probe040(!(ssw & RW_040), addr, ssw);
327 #ifdef DEBUG
328                 printk("mmusr = %lx\n", mmusr);
329 #endif
330                 errorcode = 1;
331                 if (!(mmusr & MMU_R_040)) {
332                         /* clear the invalid atc entry */
333                         __flush_tlb040_one(addr);
334                         errorcode = 0;
335                 }
336
337                 /* despite what documentation seems to say, RMW
338                  * accesses have always both the LK and RW bits set */
339                 if (!(ssw & RW_040) || (ssw & LK_040))
340                         errorcode |= 2;
341
342                 if (do_page_fault(&fp->ptregs, addr, errorcode)) {
343 #ifdef DEBUG
344                         printk("do_page_fault() !=0\n");
345 #endif
346                         if (user_mode(&fp->ptregs)){
347                                 /* delay writebacks after signal delivery */
348 #ifdef DEBUG
349                                 printk(".. was usermode - return\n");
350 #endif
351                                 return;
352                         }
353                         /* disable writeback into user space from kernel
354                          * (if do_page_fault didn't fix the mapping,
355                          * the writeback won't do good)
356                          */
357 disable_wb:
358 #ifdef DEBUG
359                         printk(".. disabling wb2\n");
360 #endif
361                         if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
362                                 fp->un.fmt7.wb2s &= ~WBV_040;
363                         if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
364                                 fp->un.fmt7.wb3s &= ~WBV_040;
365                 }
366         } else {
367                 /* In case of a bus error we either kill the process or expect
368                  * the kernel to catch the fault, which then is also responsible
369                  * for cleaning up the mess.
370                  */
371                 current->thread.signo = SIGBUS;
372                 current->thread.faddr = fp->un.fmt7.faddr;
373                 if (send_fault_sig(&fp->ptregs) >= 0)
374                         printk("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
375                                fp->un.fmt7.faddr);
376                 goto disable_wb;
377         }
378
379         do_040writebacks(fp);
380 }
381 #endif /* CONFIG_M68040 */
382
383 #if defined(CONFIG_SUN3)
384 #include <asm/sun3mmu.h>
385
386 extern int mmu_emu_handle_fault (unsigned long, int, int);
387
388 /* sun3 version of bus_error030 */
389
390 static inline void bus_error030 (struct frame *fp)
391 {
392         unsigned char buserr_type = sun3_get_buserr ();
393         unsigned long addr, errorcode;
394         unsigned short ssw = fp->un.fmtb.ssw;
395         extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
396
397 #ifdef DEBUG
398         if (ssw & (FC | FB))
399                 printk ("Instruction fault at %#010lx\n",
400                         ssw & FC ?
401                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
402                         :
403                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
404         if (ssw & DF)
405                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
406                         ssw & RW ? "read" : "write",
407                         fp->un.fmtb.daddr,
408                         space_names[ssw & DFC], fp->ptregs.pc);
409 #endif
410
411         /*
412          * Check if this page should be demand-mapped. This needs to go before
413          * the testing for a bad kernel-space access (demand-mapping applies
414          * to kernel accesses too).
415          */
416
417         if ((ssw & DF)
418             && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
419                 if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
420                         return;
421         }
422
423         /* Check for kernel-space pagefault (BAD). */
424         if (fp->ptregs.sr & PS_S) {
425                 /* kernel fault must be a data fault to user space */
426                 if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
427                      // try checking the kernel mappings before surrender
428                      if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
429                           return;
430                         /* instruction fault or kernel data fault! */
431                         if (ssw & (FC | FB))
432                                 printk ("Instruction fault at %#010lx\n",
433                                         fp->ptregs.pc);
434                         if (ssw & DF) {
435                                 /* was this fault incurred testing bus mappings? */
436                                 if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
437                                    (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
438                                         send_fault_sig(&fp->ptregs);
439                                         return;
440                                 }
441
442                                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
443                                         ssw & RW ? "read" : "write",
444                                         fp->un.fmtb.daddr,
445                                         space_names[ssw & DFC], fp->ptregs.pc);
446                         }
447                         printk ("BAD KERNEL BUSERR\n");
448
449                         die_if_kernel("Oops", &fp->ptregs,0);
450                         force_sig(SIGKILL, current);
451                         return;
452                 }
453         } else {
454                 /* user fault */
455                 if (!(ssw & (FC | FB)) && !(ssw & DF))
456                         /* not an instruction fault or data fault! BAD */
457                         panic ("USER BUSERR w/o instruction or data fault");
458         }
459
460
461         /* First handle the data fault, if any.  */
462         if (ssw & DF) {
463                 addr = fp->un.fmtb.daddr;
464
465 // errorcode bit 0:     0 -> no page            1 -> protection fault
466 // errorcode bit 1:     0 -> read fault         1 -> write fault
467
468 // (buserr_type & SUN3_BUSERR_PROTERR)  -> protection fault
469 // (buserr_type & SUN3_BUSERR_INVALID)  -> invalid page fault
470
471                 if (buserr_type & SUN3_BUSERR_PROTERR)
472                         errorcode = 0x01;
473                 else if (buserr_type & SUN3_BUSERR_INVALID)
474                         errorcode = 0x00;
475                 else {
476 #ifdef DEBUG
477                         printk ("*** unexpected busfault type=%#04x\n", buserr_type);
478                         printk ("invalid %s access at %#lx from pc %#lx\n",
479                                 !(ssw & RW) ? "write" : "read", addr,
480                                 fp->ptregs.pc);
481 #endif
482                         die_if_kernel ("Oops", &fp->ptregs, buserr_type);
483                         force_sig (SIGBUS, current);
484                         return;
485                 }
486
487 //todo: wtf is RM bit? --m
488                 if (!(ssw & RW) || ssw & RM)
489                         errorcode |= 0x02;
490
491                 /* Handle page fault. */
492                 do_page_fault (&fp->ptregs, addr, errorcode);
493
494                 /* Retry the data fault now. */
495                 return;
496         }
497
498         /* Now handle the instruction fault. */
499
500         /* Get the fault address. */
501         if (fp->ptregs.format == 0xA)
502                 addr = fp->ptregs.pc + 4;
503         else
504                 addr = fp->un.fmtb.baddr;
505         if (ssw & FC)
506                 addr -= 2;
507
508         if (buserr_type & SUN3_BUSERR_INVALID) {
509                 if (!mmu_emu_handle_fault(addr, 1, 0))
510                         do_page_fault (&fp->ptregs, addr, 0);
511        } else {
512 #ifdef DEBUG
513                 printk ("protection fault on insn access (segv).\n");
514 #endif
515                 force_sig (SIGSEGV, current);
516        }
517 }
518 #else
519 #if defined(CPU_M68020_OR_M68030)
520 static inline void bus_error030 (struct frame *fp)
521 {
522         volatile unsigned short temp;
523         unsigned short mmusr;
524         unsigned long addr, errorcode;
525         unsigned short ssw = fp->un.fmtb.ssw;
526 #ifdef DEBUG
527         unsigned long desc;
528
529         printk ("pid = %x  ", current->pid);
530         printk ("SSW=%#06x  ", ssw);
531
532         if (ssw & (FC | FB))
533                 printk ("Instruction fault at %#010lx\n",
534                         ssw & FC ?
535                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
536                         :
537                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
538         if (ssw & DF)
539                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
540                         ssw & RW ? "read" : "write",
541                         fp->un.fmtb.daddr,
542                         space_names[ssw & DFC], fp->ptregs.pc);
543 #endif
544
545         /* ++andreas: If a data fault and an instruction fault happen
546            at the same time map in both pages.  */
547
548         /* First handle the data fault, if any.  */
549         if (ssw & DF) {
550                 addr = fp->un.fmtb.daddr;
551
552 #ifdef DEBUG
553                 asm volatile ("ptestr %3,%2@,#7,%0\n\t"
554                               "pmove %%psr,%1"
555                               : "=a&" (desc), "=m" (temp)
556                               : "a" (addr), "d" (ssw));
557 #else
558                 asm volatile ("ptestr %2,%1@,#7\n\t"
559                               "pmove %%psr,%0"
560                               : "=m" (temp) : "a" (addr), "d" (ssw));
561 #endif
562                 mmusr = temp;
563
564 #ifdef DEBUG
565                 printk("mmusr is %#x for addr %#lx in task %p\n",
566                        mmusr, addr, current);
567                 printk("descriptor address is %#lx, contents %#lx\n",
568                        __va(desc), *(unsigned long *)__va(desc));
569 #endif
570
571                 errorcode = (mmusr & MMU_I) ? 0 : 1;
572                 if (!(ssw & RW) || (ssw & RM))
573                         errorcode |= 2;
574
575                 if (mmusr & (MMU_I | MMU_WP)) {
576                         if (ssw & 4) {
577                                 printk("Data %s fault at %#010lx in %s (pc=%#lx)\n",
578                                        ssw & RW ? "read" : "write",
579                                        fp->un.fmtb.daddr,
580                                        space_names[ssw & DFC], fp->ptregs.pc);
581                                 goto buserr;
582                         }
583                         /* Don't try to do anything further if an exception was
584                            handled. */
585                         if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
586                                 return;
587                 } else if (!(mmusr & MMU_I)) {
588                         /* probably a 020 cas fault */
589                         if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
590                                 printk("unexpected bus error (%#x,%#x)\n", ssw, mmusr);
591                 } else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
592                         printk("invalid %s access at %#lx from pc %#lx\n",
593                                !(ssw & RW) ? "write" : "read", addr,
594                                fp->ptregs.pc);
595                         die_if_kernel("Oops",&fp->ptregs,mmusr);
596                         force_sig(SIGSEGV, current);
597                         return;
598                 } else {
599 #if 0
600                         static volatile long tlong;
601 #endif
602
603                         printk("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
604                                !(ssw & RW) ? "write" : "read", addr,
605                                fp->ptregs.pc, ssw);
606                         asm volatile ("ptestr #1,%1@,#0\n\t"
607                                       "pmove %%psr,%0"
608                                       : "=m" (temp)
609                                       : "a" (addr));
610                         mmusr = temp;
611
612                         printk ("level 0 mmusr is %#x\n", mmusr);
613 #if 0
614                         asm volatile ("pmove %%tt0,%0"
615                                       : "=m" (tlong));
616                         printk("tt0 is %#lx, ", tlong);
617                         asm volatile ("pmove %%tt1,%0"
618                                       : "=m" (tlong));
619                         printk("tt1 is %#lx\n", tlong);
620 #endif
621 #ifdef DEBUG
622                         printk("Unknown SIGSEGV - 1\n");
623 #endif
624                         die_if_kernel("Oops",&fp->ptregs,mmusr);
625                         force_sig(SIGSEGV, current);
626                         return;
627                 }
628
629                 /* setup an ATC entry for the access about to be retried */
630                 if (!(ssw & RW) || (ssw & RM))
631                         asm volatile ("ploadw %1,%0@" : /* no outputs */
632                                       : "a" (addr), "d" (ssw));
633                 else
634                         asm volatile ("ploadr %1,%0@" : /* no outputs */
635                                       : "a" (addr), "d" (ssw));
636         }
637
638         /* Now handle the instruction fault. */
639
640         if (!(ssw & (FC|FB)))
641                 return;
642
643         if (fp->ptregs.sr & PS_S) {
644                 printk("Instruction fault at %#010lx\n",
645                         fp->ptregs.pc);
646         buserr:
647                 printk ("BAD KERNEL BUSERR\n");
648                 die_if_kernel("Oops",&fp->ptregs,0);
649                 force_sig(SIGKILL, current);
650                 return;
651         }
652
653         /* get the fault address */
654         if (fp->ptregs.format == 10)
655                 addr = fp->ptregs.pc + 4;
656         else
657                 addr = fp->un.fmtb.baddr;
658         if (ssw & FC)
659                 addr -= 2;
660
661         if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
662                 /* Insn fault on same page as data fault.  But we
663                    should still create the ATC entry.  */
664                 goto create_atc_entry;
665
666 #ifdef DEBUG
667         asm volatile ("ptestr #1,%2@,#7,%0\n\t"
668                       "pmove %%psr,%1"
669                       : "=a&" (desc), "=m" (temp)
670                       : "a" (addr));
671 #else
672         asm volatile ("ptestr #1,%1@,#7\n\t"
673                       "pmove %%psr,%0"
674                       : "=m" (temp) : "a" (addr));
675 #endif
676         mmusr = temp;
677
678 #ifdef DEBUG
679         printk ("mmusr is %#x for addr %#lx in task %p\n",
680                 mmusr, addr, current);
681         printk ("descriptor address is %#lx, contents %#lx\n",
682                 __va(desc), *(unsigned long *)__va(desc));
683 #endif
684
685         if (mmusr & MMU_I)
686                 do_page_fault (&fp->ptregs, addr, 0);
687         else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
688                 printk ("invalid insn access at %#lx from pc %#lx\n",
689                         addr, fp->ptregs.pc);
690 #ifdef DEBUG
691                 printk("Unknown SIGSEGV - 2\n");
692 #endif
693                 die_if_kernel("Oops",&fp->ptregs,mmusr);
694                 force_sig(SIGSEGV, current);
695                 return;
696         }
697
698 create_atc_entry:
699         /* setup an ATC entry for the access about to be retried */
700         asm volatile ("ploadr #2,%0@" : /* no outputs */
701                       : "a" (addr));
702 }
703 #endif /* CPU_M68020_OR_M68030 */
704 #endif /* !CONFIG_SUN3 */
705
706 #if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
707 #include <asm/mcfmmu.h>
708
709 /*
710  *      The following table converts the FS encoding of a ColdFire
711  *      exception stack frame into the error_code value needed by
712  *      do_fault.
713 */
714 static const unsigned char fs_err_code[] = {
715         0,  /* 0000 */
716         0,  /* 0001 */
717         0,  /* 0010 */
718         0,  /* 0011 */
719         1,  /* 0100 */
720         0,  /* 0101 */
721         0,  /* 0110 */
722         0,  /* 0111 */
723         2,  /* 1000 */
724         3,  /* 1001 */
725         2,  /* 1010 */
726         0,  /* 1011 */
727         1,  /* 1100 */
728         1,  /* 1101 */
729         0,  /* 1110 */
730         0   /* 1111 */
731 };
732
733 static inline void access_errorcf(unsigned int fs, struct frame *fp)
734 {
735         unsigned long mmusr, addr;
736         unsigned int err_code;
737         int need_page_fault;
738
739         mmusr = mmu_read(MMUSR);
740         addr = mmu_read(MMUAR);
741
742         /*
743          * error_code:
744          *      bit 0 == 0 means no page found, 1 means protection fault
745          *      bit 1 == 0 means read, 1 means write
746          */
747         switch (fs) {
748         case  5:  /* 0101 TLB opword X miss */
749                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 0);
750                 addr = fp->ptregs.pc;
751                 break;
752         case  6:  /* 0110 TLB extension word X miss */
753                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 1);
754                 addr = fp->ptregs.pc + sizeof(long);
755                 break;
756         case 10:  /* 1010 TLB W miss */
757                 need_page_fault = cf_tlb_miss(&fp->ptregs, 1, 1, 0);
758                 break;
759         case 14: /* 1110 TLB R miss */
760                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 1, 0);
761                 break;
762         default:
763                 /* 0000 Normal  */
764                 /* 0001 Reserved */
765                 /* 0010 Interrupt during debug service routine */
766                 /* 0011 Reserved */
767                 /* 0100 X Protection */
768                 /* 0111 IFP in emulator mode */
769                 /* 1000 W Protection*/
770                 /* 1001 Write error*/
771                 /* 1011 Reserved*/
772                 /* 1100 R Protection*/
773                 /* 1101 R Protection*/
774                 /* 1111 OEP in emulator mode*/
775                 need_page_fault = 1;
776                 break;
777         }
778
779         if (need_page_fault) {
780                 err_code = fs_err_code[fs];
781                 if ((fs == 13) && (mmusr & MMUSR_WF)) /* rd-mod-wr access */
782                         err_code |= 2; /* bit1 - write, bit0 - protection */
783                 do_page_fault(&fp->ptregs, addr, err_code);
784         }
785 }
786 #endif /* CONFIG_COLDFIRE CONFIG_MMU */
787
788 asmlinkage void buserr_c(struct frame *fp)
789 {
790         /* Only set esp0 if coming from user mode */
791         if (user_mode(&fp->ptregs))
792                 current->thread.esp0 = (unsigned long) fp;
793
794 #ifdef DEBUG
795         printk ("*** Bus Error *** Format is %x\n", fp->ptregs.format);
796 #endif
797
798 #if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
799         if (CPU_IS_COLDFIRE) {
800                 unsigned int fs;
801                 fs = (fp->ptregs.vector & 0x3) |
802                         ((fp->ptregs.vector & 0xc00) >> 8);
803                 switch (fs) {
804                 case 0x5:
805                 case 0x6:
806                 case 0x7:
807                 case 0x9:
808                 case 0xa:
809                 case 0xd:
810                 case 0xe:
811                 case 0xf:
812                         access_errorcf(fs, fp);
813                         return;
814                 default:
815                         break;
816                 }
817         }
818 #endif /* CONFIG_COLDFIRE && CONFIG_MMU */
819
820         switch (fp->ptregs.format) {
821 #if defined (CONFIG_M68060)
822         case 4:                         /* 68060 access error */
823           access_error060 (fp);
824           break;
825 #endif
826 #if defined (CONFIG_M68040)
827         case 0x7:                       /* 68040 access error */
828           access_error040 (fp);
829           break;
830 #endif
831 #if defined (CPU_M68020_OR_M68030)
832         case 0xa:
833         case 0xb:
834           bus_error030 (fp);
835           break;
836 #endif
837         default:
838           die_if_kernel("bad frame format",&fp->ptregs,0);
839 #ifdef DEBUG
840           printk("Unknown SIGSEGV - 4\n");
841 #endif
842           force_sig(SIGSEGV, current);
843         }
844 }
845
846
847 static int kstack_depth_to_print = 48;
848
849 void show_trace(unsigned long *stack)
850 {
851         unsigned long *endstack;
852         unsigned long addr;
853         int i;
854
855         printk("Call Trace:");
856         addr = (unsigned long)stack + THREAD_SIZE - 1;
857         endstack = (unsigned long *)(addr & -THREAD_SIZE);
858         i = 0;
859         while (stack + 1 <= endstack) {
860                 addr = *stack++;
861                 /*
862                  * If the address is either in the text segment of the
863                  * kernel, or in the region which contains vmalloc'ed
864                  * memory, it *may* be the address of a calling
865                  * routine; if so, print it so that someone tracing
866                  * down the cause of the crash will be able to figure
867                  * out the call path that was taken.
868                  */
869                 if (__kernel_text_address(addr)) {
870 #ifndef CONFIG_KALLSYMS
871                         if (i % 5 == 0)
872                                 printk("\n       ");
873 #endif
874                         printk(" [<%08lx>] %pS\n", addr, (void *)addr);
875                         i++;
876                 }
877         }
878         printk("\n");
879 }
880
881 void show_registers(struct pt_regs *regs)
882 {
883         struct frame *fp = (struct frame *)regs;
884         mm_segment_t old_fs = get_fs();
885         u16 c, *cp;
886         unsigned long addr;
887         int i;
888
889         print_modules();
890         printk("PC: [<%08lx>] %pS\n", regs->pc, (void *)regs->pc);
891         printk("SR: %04x  SP: %p  a2: %08lx\n", regs->sr, regs, regs->a2);
892         printk("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
893                regs->d0, regs->d1, regs->d2, regs->d3);
894         printk("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
895                regs->d4, regs->d5, regs->a0, regs->a1);
896
897         printk("Process %s (pid: %d, task=%p)\n",
898                 current->comm, task_pid_nr(current), current);
899         addr = (unsigned long)&fp->un;
900         printk("Frame format=%X ", regs->format);
901         switch (regs->format) {
902         case 0x2:
903                 printk("instr addr=%08lx\n", fp->un.fmt2.iaddr);
904                 addr += sizeof(fp->un.fmt2);
905                 break;
906         case 0x3:
907                 printk("eff addr=%08lx\n", fp->un.fmt3.effaddr);
908                 addr += sizeof(fp->un.fmt3);
909                 break;
910         case 0x4:
911                 printk((CPU_IS_060 ? "fault addr=%08lx fslw=%08lx\n"
912                         : "eff addr=%08lx pc=%08lx\n"),
913                         fp->un.fmt4.effaddr, fp->un.fmt4.pc);
914                 addr += sizeof(fp->un.fmt4);
915                 break;
916         case 0x7:
917                 printk("eff addr=%08lx ssw=%04x faddr=%08lx\n",
918                         fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
919                 printk("wb 1 stat/addr/data: %04x %08lx %08lx\n",
920                         fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
921                 printk("wb 2 stat/addr/data: %04x %08lx %08lx\n",
922                         fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
923                 printk("wb 3 stat/addr/data: %04x %08lx %08lx\n",
924                         fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
925                 printk("push data: %08lx %08lx %08lx %08lx\n",
926                         fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
927                         fp->un.fmt7.pd3);
928                 addr += sizeof(fp->un.fmt7);
929                 break;
930         case 0x9:
931                 printk("instr addr=%08lx\n", fp->un.fmt9.iaddr);
932                 addr += sizeof(fp->un.fmt9);
933                 break;
934         case 0xa:
935                 printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
936                         fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
937                         fp->un.fmta.daddr, fp->un.fmta.dobuf);
938                 addr += sizeof(fp->un.fmta);
939                 break;
940         case 0xb:
941                 printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
942                         fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
943                         fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
944                 printk("baddr=%08lx dibuf=%08lx ver=%x\n",
945                         fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
946                 addr += sizeof(fp->un.fmtb);
947                 break;
948         default:
949                 printk("\n");
950         }
951         show_stack(NULL, (unsigned long *)addr);
952
953         printk("Code:");
954         set_fs(KERNEL_DS);
955         cp = (u16 *)regs->pc;
956         for (i = -8; i < 16; i++) {
957                 if (get_user(c, cp + i) && i >= 0) {
958                         printk(" Bad PC value.");
959                         break;
960                 }
961                 printk(i ? " %04x" : " <%04x>", c);
962         }
963         set_fs(old_fs);
964         printk ("\n");
965 }
966
967 void show_stack(struct task_struct *task, unsigned long *stack)
968 {
969         unsigned long *p;
970         unsigned long *endstack;
971         int i;
972
973         if (!stack) {
974                 if (task)
975                         stack = (unsigned long *)task->thread.esp0;
976                 else
977                         stack = (unsigned long *)&stack;
978         }
979         endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
980
981         printk("Stack from %08lx:", (unsigned long)stack);
982         p = stack;
983         for (i = 0; i < kstack_depth_to_print; i++) {
984                 if (p + 1 > endstack)
985                         break;
986                 if (i % 8 == 0)
987                         printk("\n       ");
988                 printk(" %08lx", *p++);
989         }
990         printk("\n");
991         show_trace(stack);
992 }
993
994 /*
995  * The vector number returned in the frame pointer may also contain
996  * the "fs" (Fault Status) bits on ColdFire. These are in the bottom
997  * 2 bits, and upper 2 bits. So we need to mask out the real vector
998  * number before using it in comparisons. You don't need to do this on
999  * real 68k parts, but it won't hurt either.
1000  */
1001
1002 void bad_super_trap (struct frame *fp)
1003 {
1004         int vector = (fp->ptregs.vector >> 2) & 0xff;
1005
1006         console_verbose();
1007         if (vector < ARRAY_SIZE(vec_names))
1008                 printk ("*** %s ***   FORMAT=%X\n",
1009                         vec_names[vector],
1010                         fp->ptregs.format);
1011         else
1012                 printk ("*** Exception %d ***   FORMAT=%X\n",
1013                         vector, fp->ptregs.format);
1014         if (vector == VEC_ADDRERR && CPU_IS_020_OR_030) {
1015                 unsigned short ssw = fp->un.fmtb.ssw;
1016
1017                 printk ("SSW=%#06x  ", ssw);
1018
1019                 if (ssw & RC)
1020                         printk ("Pipe stage C instruction fault at %#010lx\n",
1021                                 (fp->ptregs.format) == 0xA ?
1022                                 fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
1023                 if (ssw & RB)
1024                         printk ("Pipe stage B instruction fault at %#010lx\n",
1025                                 (fp->ptregs.format) == 0xA ?
1026                                 fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
1027                 if (ssw & DF)
1028                         printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
1029                                 ssw & RW ? "read" : "write",
1030                                 fp->un.fmtb.daddr, space_names[ssw & DFC],
1031                                 fp->ptregs.pc);
1032         }
1033         printk ("Current process id is %d\n", task_pid_nr(current));
1034         die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
1035 }
1036
1037 asmlinkage void trap_c(struct frame *fp)
1038 {
1039         int sig;
1040         int vector = (fp->ptregs.vector >> 2) & 0xff;
1041         siginfo_t info;
1042
1043         if (fp->ptregs.sr & PS_S) {
1044                 if (vector == VEC_TRACE) {
1045                         /* traced a trapping instruction on a 68020/30,
1046                          * real exception will be executed afterwards.
1047                          */
1048                 } else if (!handle_kernel_fault(&fp->ptregs))
1049                         bad_super_trap(fp);
1050                 return;
1051         }
1052
1053         /* send the appropriate signal to the user program */
1054         switch (vector) {
1055             case VEC_ADDRERR:
1056                 info.si_code = BUS_ADRALN;
1057                 sig = SIGBUS;
1058                 break;
1059             case VEC_ILLEGAL:
1060             case VEC_LINE10:
1061             case VEC_LINE11:
1062                 info.si_code = ILL_ILLOPC;
1063                 sig = SIGILL;
1064                 break;
1065             case VEC_PRIV:
1066                 info.si_code = ILL_PRVOPC;
1067                 sig = SIGILL;
1068                 break;
1069             case VEC_COPROC:
1070                 info.si_code = ILL_COPROC;
1071                 sig = SIGILL;
1072                 break;
1073             case VEC_TRAP1:
1074             case VEC_TRAP2:
1075             case VEC_TRAP3:
1076             case VEC_TRAP4:
1077             case VEC_TRAP5:
1078             case VEC_TRAP6:
1079             case VEC_TRAP7:
1080             case VEC_TRAP8:
1081             case VEC_TRAP9:
1082             case VEC_TRAP10:
1083             case VEC_TRAP11:
1084             case VEC_TRAP12:
1085             case VEC_TRAP13:
1086             case VEC_TRAP14:
1087                 info.si_code = ILL_ILLTRP;
1088                 sig = SIGILL;
1089                 break;
1090             case VEC_FPBRUC:
1091             case VEC_FPOE:
1092             case VEC_FPNAN:
1093                 info.si_code = FPE_FLTINV;
1094                 sig = SIGFPE;
1095                 break;
1096             case VEC_FPIR:
1097                 info.si_code = FPE_FLTRES;
1098                 sig = SIGFPE;
1099                 break;
1100             case VEC_FPDIVZ:
1101                 info.si_code = FPE_FLTDIV;
1102                 sig = SIGFPE;
1103                 break;
1104             case VEC_FPUNDER:
1105                 info.si_code = FPE_FLTUND;
1106                 sig = SIGFPE;
1107                 break;
1108             case VEC_FPOVER:
1109                 info.si_code = FPE_FLTOVF;
1110                 sig = SIGFPE;
1111                 break;
1112             case VEC_ZERODIV:
1113                 info.si_code = FPE_INTDIV;
1114                 sig = SIGFPE;
1115                 break;
1116             case VEC_CHK:
1117             case VEC_TRAP:
1118                 info.si_code = FPE_INTOVF;
1119                 sig = SIGFPE;
1120                 break;
1121             case VEC_TRACE:             /* ptrace single step */
1122                 info.si_code = TRAP_TRACE;
1123                 sig = SIGTRAP;
1124                 break;
1125             case VEC_TRAP15:            /* breakpoint */
1126                 info.si_code = TRAP_BRKPT;
1127                 sig = SIGTRAP;
1128                 break;
1129             default:
1130                 info.si_code = ILL_ILLOPC;
1131                 sig = SIGILL;
1132                 break;
1133         }
1134         info.si_signo = sig;
1135         info.si_errno = 0;
1136         switch (fp->ptregs.format) {
1137             default:
1138                 info.si_addr = (void *) fp->ptregs.pc;
1139                 break;
1140             case 2:
1141                 info.si_addr = (void *) fp->un.fmt2.iaddr;
1142                 break;
1143             case 7:
1144                 info.si_addr = (void *) fp->un.fmt7.effaddr;
1145                 break;
1146             case 9:
1147                 info.si_addr = (void *) fp->un.fmt9.iaddr;
1148                 break;
1149             case 10:
1150                 info.si_addr = (void *) fp->un.fmta.daddr;
1151                 break;
1152             case 11:
1153                 info.si_addr = (void *) fp->un.fmtb.daddr;
1154                 break;
1155         }
1156         force_sig_info (sig, &info, current);
1157 }
1158
1159 void die_if_kernel (char *str, struct pt_regs *fp, int nr)
1160 {
1161         if (!(fp->sr & PS_S))
1162                 return;
1163
1164         console_verbose();
1165         printk("%s: %08x\n",str,nr);
1166         show_registers(fp);
1167         add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
1168         do_exit(SIGSEGV);
1169 }
1170
1171 asmlinkage void set_esp0(unsigned long ssp)
1172 {
1173         current->thread.esp0 = ssp;
1174 }
1175
1176 /*
1177  * This function is called if an error occur while accessing
1178  * user-space from the fpsp040 code.
1179  */
1180 asmlinkage void fpsp040_die(void)
1181 {
1182         do_exit(SIGSEGV);
1183 }
1184
1185 #ifdef CONFIG_M68KFPU_EMU
1186 asmlinkage void fpemu_signal(int signal, int code, void *addr)
1187 {
1188         siginfo_t info;
1189
1190         info.si_signo = signal;
1191         info.si_errno = 0;
1192         info.si_code = code;
1193         info.si_addr = addr;
1194         force_sig_info(signal, &info, current);
1195 }
1196 #endif