Merge tag 'for-5.15/io_uring-2021-09-04' of git://git.kernel.dk/linux-block
[linux-2.6-microblaze.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/sched/debug.h>
23 #include <linux/signal.h>
24 #include <linux/kernel.h>
25 #include <linux/mm.h>
26 #include <linux/module.h>
27 #include <linux/user.h>
28 #include <linux/string.h>
29 #include <linux/linkage.h>
30 #include <linux/init.h>
31 #include <linux/ptrace.h>
32 #include <linux/kallsyms.h>
33
34 #include <asm/setup.h>
35 #include <asm/fpu.h>
36 #include <linux/uaccess.h>
37 #include <asm/traps.h>
38 #include <asm/machdep.h>
39 #include <asm/siginfo.h>
40 #include <asm/tlbflush.h>
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         pr_debug("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
137
138         if (fslw & MMU060_BPE) {
139                 /* branch prediction error -> clear branch cache */
140                 __asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
141                                       "orl   #0x00400000,%/d0\n\t"
142                                       "movec %/d0,%/cacr"
143                                       : : : "d0" );
144                 /* return if there's no other error */
145                 if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
146                         return;
147         }
148
149         if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
150                 unsigned long errorcode;
151                 unsigned long addr = fp->un.fmt4.effaddr;
152
153                 if (fslw & MMU060_MA)
154                         addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
155
156                 errorcode = 1;
157                 if (fslw & MMU060_DESC_ERR) {
158                         __flush_tlb040_one(addr);
159                         errorcode = 0;
160                 }
161                 if (fslw & MMU060_W)
162                         errorcode |= 2;
163                 pr_debug("errorcode = %ld\n", errorcode);
164                 do_page_fault(&fp->ptregs, addr, errorcode);
165         } else if (fslw & (MMU060_SEE)){
166                 /* Software Emulation Error.
167                  * fault during mem_read/mem_write in ifpsp060/os.S
168                  */
169                 send_fault_sig(&fp->ptregs);
170         } else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
171                    send_fault_sig(&fp->ptregs) > 0) {
172                 pr_err("pc=%#lx, fa=%#lx\n", fp->ptregs.pc,
173                        fp->un.fmt4.effaddr);
174                 pr_err("68060 access error, fslw=%lx\n", fslw);
175                 trap_c( fp );
176         }
177 }
178 #endif /* CONFIG_M68060 */
179
180 #if defined (CONFIG_M68040)
181 static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
182 {
183         unsigned long mmusr;
184         mm_segment_t old_fs = get_fs();
185
186         set_fs(MAKE_MM_SEG(wbs));
187
188         if (iswrite)
189                 asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
190         else
191                 asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
192
193         asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
194
195         set_fs(old_fs);
196
197         return mmusr;
198 }
199
200 static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
201                                    unsigned long wbd)
202 {
203         int res = 0;
204         mm_segment_t old_fs = get_fs();
205
206         /* set_fs can not be moved, otherwise put_user() may oops */
207         set_fs(MAKE_MM_SEG(wbs));
208
209         switch (wbs & WBSIZ_040) {
210         case BA_SIZE_BYTE:
211                 res = put_user(wbd & 0xff, (char __user *)wba);
212                 break;
213         case BA_SIZE_WORD:
214                 res = put_user(wbd & 0xffff, (short __user *)wba);
215                 break;
216         case BA_SIZE_LONG:
217                 res = put_user(wbd, (int __user *)wba);
218                 break;
219         }
220
221         /* set_fs can not be moved, otherwise put_user() may oops */
222         set_fs(old_fs);
223
224
225         pr_debug("do_040writeback1, res=%d\n", res);
226
227         return res;
228 }
229
230 /* after an exception in a writeback the stack frame corresponding
231  * to that exception is discarded, set a few bits in the old frame
232  * to simulate what it should look like
233  */
234 static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
235 {
236         fp->un.fmt7.faddr = wba;
237         fp->un.fmt7.ssw = wbs & 0xff;
238         if (wba != current->thread.faddr)
239             fp->un.fmt7.ssw |= MA_040;
240 }
241
242 static inline void do_040writebacks(struct frame *fp)
243 {
244         int res = 0;
245 #if 0
246         if (fp->un.fmt7.wb1s & WBV_040)
247                 pr_err("access_error040: cannot handle 1st writeback. oops.\n");
248 #endif
249
250         if ((fp->un.fmt7.wb2s & WBV_040) &&
251             !(fp->un.fmt7.wb2s & WBTT_040)) {
252                 res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
253                                        fp->un.fmt7.wb2d);
254                 if (res)
255                         fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
256                 else
257                         fp->un.fmt7.wb2s = 0;
258         }
259
260         /* do the 2nd wb only if the first one was successful (except for a kernel wb) */
261         if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
262                 res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
263                                        fp->un.fmt7.wb3d);
264                 if (res)
265                     {
266                         fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
267
268                         fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
269                         fp->un.fmt7.wb3s &= (~WBV_040);
270                         fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
271                         fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
272                     }
273                 else
274                         fp->un.fmt7.wb3s = 0;
275         }
276
277         if (res)
278                 send_fault_sig(&fp->ptregs);
279 }
280
281 /*
282  * called from sigreturn(), must ensure userspace code didn't
283  * manipulate exception frame to circumvent protection, then complete
284  * pending writebacks
285  * we just clear TM2 to turn it into a userspace access
286  */
287 asmlinkage void berr_040cleanup(struct frame *fp)
288 {
289         fp->un.fmt7.wb2s &= ~4;
290         fp->un.fmt7.wb3s &= ~4;
291
292         do_040writebacks(fp);
293 }
294
295 static inline void access_error040(struct frame *fp)
296 {
297         unsigned short ssw = fp->un.fmt7.ssw;
298         unsigned long mmusr;
299
300         pr_debug("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
301         pr_debug("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
302                 fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
303         pr_debug("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
304                 fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
305                 fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
306
307         if (ssw & ATC_040) {
308                 unsigned long addr = fp->un.fmt7.faddr;
309                 unsigned long errorcode;
310
311                 /*
312                  * The MMU status has to be determined AFTER the address
313                  * has been corrected if there was a misaligned access (MA).
314                  */
315                 if (ssw & MA_040)
316                         addr = (addr + 7) & -8;
317
318                 /* MMU error, get the MMUSR info for this access */
319                 mmusr = probe040(!(ssw & RW_040), addr, ssw);
320                 pr_debug("mmusr = %lx\n", mmusr);
321                 errorcode = 1;
322                 if (!(mmusr & MMU_R_040)) {
323                         /* clear the invalid atc entry */
324                         __flush_tlb040_one(addr);
325                         errorcode = 0;
326                 }
327
328                 /* despite what documentation seems to say, RMW
329                  * accesses have always both the LK and RW bits set */
330                 if (!(ssw & RW_040) || (ssw & LK_040))
331                         errorcode |= 2;
332
333                 if (do_page_fault(&fp->ptregs, addr, errorcode)) {
334                         pr_debug("do_page_fault() !=0\n");
335                         if (user_mode(&fp->ptregs)){
336                                 /* delay writebacks after signal delivery */
337                                 pr_debug(".. was usermode - return\n");
338                                 return;
339                         }
340                         /* disable writeback into user space from kernel
341                          * (if do_page_fault didn't fix the mapping,
342                          * the writeback won't do good)
343                          */
344 disable_wb:
345                         pr_debug(".. disabling wb2\n");
346                         if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
347                                 fp->un.fmt7.wb2s &= ~WBV_040;
348                         if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
349                                 fp->un.fmt7.wb3s &= ~WBV_040;
350                 }
351         } else {
352                 /* In case of a bus error we either kill the process or expect
353                  * the kernel to catch the fault, which then is also responsible
354                  * for cleaning up the mess.
355                  */
356                 current->thread.signo = SIGBUS;
357                 current->thread.faddr = fp->un.fmt7.faddr;
358                 if (send_fault_sig(&fp->ptregs) >= 0)
359                         pr_err("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
360                                fp->un.fmt7.faddr);
361                 goto disable_wb;
362         }
363
364         do_040writebacks(fp);
365 }
366 #endif /* CONFIG_M68040 */
367
368 #if defined(CONFIG_SUN3)
369 #include <asm/sun3mmu.h>
370
371 extern int mmu_emu_handle_fault (unsigned long, int, int);
372
373 /* sun3 version of bus_error030 */
374
375 static inline void bus_error030 (struct frame *fp)
376 {
377         unsigned char buserr_type = sun3_get_buserr ();
378         unsigned long addr, errorcode;
379         unsigned short ssw = fp->un.fmtb.ssw;
380         extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
381
382         if (ssw & (FC | FB))
383                 pr_debug("Instruction fault at %#010lx\n",
384                         ssw & FC ?
385                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
386                         :
387                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
388         if (ssw & DF)
389                 pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
390                         ssw & RW ? "read" : "write",
391                         fp->un.fmtb.daddr,
392                         space_names[ssw & DFC], fp->ptregs.pc);
393
394         /*
395          * Check if this page should be demand-mapped. This needs to go before
396          * the testing for a bad kernel-space access (demand-mapping applies
397          * to kernel accesses too).
398          */
399
400         if ((ssw & DF)
401             && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
402                 if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
403                         return;
404         }
405
406         /* Check for kernel-space pagefault (BAD). */
407         if (fp->ptregs.sr & PS_S) {
408                 /* kernel fault must be a data fault to user space */
409                 if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
410                      // try checking the kernel mappings before surrender
411                      if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
412                           return;
413                         /* instruction fault or kernel data fault! */
414                         if (ssw & (FC | FB))
415                                 pr_err("Instruction fault at %#010lx\n",
416                                         fp->ptregs.pc);
417                         if (ssw & DF) {
418                                 /* was this fault incurred testing bus mappings? */
419                                 if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
420                                    (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
421                                         send_fault_sig(&fp->ptregs);
422                                         return;
423                                 }
424
425                                 pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
426                                         ssw & RW ? "read" : "write",
427                                         fp->un.fmtb.daddr,
428                                         space_names[ssw & DFC], fp->ptregs.pc);
429                         }
430                         pr_err("BAD KERNEL BUSERR\n");
431
432                         die_if_kernel("Oops", &fp->ptregs,0);
433                         force_sig(SIGKILL);
434                         return;
435                 }
436         } else {
437                 /* user fault */
438                 if (!(ssw & (FC | FB)) && !(ssw & DF))
439                         /* not an instruction fault or data fault! BAD */
440                         panic ("USER BUSERR w/o instruction or data fault");
441         }
442
443
444         /* First handle the data fault, if any.  */
445         if (ssw & DF) {
446                 addr = fp->un.fmtb.daddr;
447
448 // errorcode bit 0:     0 -> no page            1 -> protection fault
449 // errorcode bit 1:     0 -> read fault         1 -> write fault
450
451 // (buserr_type & SUN3_BUSERR_PROTERR)  -> protection fault
452 // (buserr_type & SUN3_BUSERR_INVALID)  -> invalid page fault
453
454                 if (buserr_type & SUN3_BUSERR_PROTERR)
455                         errorcode = 0x01;
456                 else if (buserr_type & SUN3_BUSERR_INVALID)
457                         errorcode = 0x00;
458                 else {
459                         pr_debug("*** unexpected busfault type=%#04x\n",
460                                  buserr_type);
461                         pr_debug("invalid %s access at %#lx from pc %#lx\n",
462                                  !(ssw & RW) ? "write" : "read", addr,
463                                  fp->ptregs.pc);
464                         die_if_kernel ("Oops", &fp->ptregs, buserr_type);
465                         force_sig (SIGBUS);
466                         return;
467                 }
468
469 //todo: wtf is RM bit? --m
470                 if (!(ssw & RW) || ssw & RM)
471                         errorcode |= 0x02;
472
473                 /* Handle page fault. */
474                 do_page_fault (&fp->ptregs, addr, errorcode);
475
476                 /* Retry the data fault now. */
477                 return;
478         }
479
480         /* Now handle the instruction fault. */
481
482         /* Get the fault address. */
483         if (fp->ptregs.format == 0xA)
484                 addr = fp->ptregs.pc + 4;
485         else
486                 addr = fp->un.fmtb.baddr;
487         if (ssw & FC)
488                 addr -= 2;
489
490         if (buserr_type & SUN3_BUSERR_INVALID) {
491                 if (!mmu_emu_handle_fault(addr, 1, 0))
492                         do_page_fault (&fp->ptregs, addr, 0);
493        } else {
494                 pr_debug("protection fault on insn access (segv).\n");
495                 force_sig (SIGSEGV);
496        }
497 }
498 #else
499 #if defined(CPU_M68020_OR_M68030)
500 static inline void bus_error030 (struct frame *fp)
501 {
502         volatile unsigned short temp;
503         unsigned short mmusr;
504         unsigned long addr, errorcode;
505         unsigned short ssw = fp->un.fmtb.ssw;
506 #ifdef DEBUG
507         unsigned long desc;
508 #endif
509
510         pr_debug("pid = %x  ", current->pid);
511         pr_debug("SSW=%#06x  ", ssw);
512
513         if (ssw & (FC | FB))
514                 pr_debug("Instruction fault at %#010lx\n",
515                         ssw & FC ?
516                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
517                         :
518                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
519         if (ssw & DF)
520                 pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
521                         ssw & RW ? "read" : "write",
522                         fp->un.fmtb.daddr,
523                         space_names[ssw & DFC], fp->ptregs.pc);
524
525         /* ++andreas: If a data fault and an instruction fault happen
526            at the same time map in both pages.  */
527
528         /* First handle the data fault, if any.  */
529         if (ssw & DF) {
530                 addr = fp->un.fmtb.daddr;
531
532 #ifdef DEBUG
533                 asm volatile ("ptestr %3,%2@,#7,%0\n\t"
534                               "pmove %%psr,%1"
535                               : "=a&" (desc), "=m" (temp)
536                               : "a" (addr), "d" (ssw));
537                 pr_debug("mmusr is %#x for addr %#lx in task %p\n",
538                          temp, addr, current);
539                 pr_debug("descriptor address is 0x%p, contents %#lx\n",
540                          __va(desc), *(unsigned long *)__va(desc));
541 #else
542                 asm volatile ("ptestr %2,%1@,#7\n\t"
543                               "pmove %%psr,%0"
544                               : "=m" (temp) : "a" (addr), "d" (ssw));
545 #endif
546                 mmusr = temp;
547                 errorcode = (mmusr & MMU_I) ? 0 : 1;
548                 if (!(ssw & RW) || (ssw & RM))
549                         errorcode |= 2;
550
551                 if (mmusr & (MMU_I | MMU_WP)) {
552                         if (ssw & 4) {
553                                 pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
554                                        ssw & RW ? "read" : "write",
555                                        fp->un.fmtb.daddr,
556                                        space_names[ssw & DFC], fp->ptregs.pc);
557                                 goto buserr;
558                         }
559                         /* Don't try to do anything further if an exception was
560                            handled. */
561                         if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
562                                 return;
563                 } else if (!(mmusr & MMU_I)) {
564                         /* probably a 020 cas fault */
565                         if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
566                                 pr_err("unexpected bus error (%#x,%#x)\n", ssw,
567                                        mmusr);
568                 } else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
569                         pr_err("invalid %s access at %#lx from pc %#lx\n",
570                                !(ssw & RW) ? "write" : "read", addr,
571                                fp->ptregs.pc);
572                         die_if_kernel("Oops",&fp->ptregs,mmusr);
573                         force_sig(SIGSEGV);
574                         return;
575                 } else {
576 #if 0
577                         static volatile long tlong;
578 #endif
579
580                         pr_err("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
581                                !(ssw & RW) ? "write" : "read", addr,
582                                fp->ptregs.pc, ssw);
583                         asm volatile ("ptestr #1,%1@,#0\n\t"
584                                       "pmove %%psr,%0"
585                                       : "=m" (temp)
586                                       : "a" (addr));
587                         mmusr = temp;
588
589                         pr_err("level 0 mmusr is %#x\n", mmusr);
590 #if 0
591                         asm volatile ("pmove %%tt0,%0"
592                                       : "=m" (tlong));
593                         pr_debug("tt0 is %#lx, ", tlong);
594                         asm volatile ("pmove %%tt1,%0"
595                                       : "=m" (tlong));
596                         pr_debug("tt1 is %#lx\n", tlong);
597 #endif
598                         pr_debug("Unknown SIGSEGV - 1\n");
599                         die_if_kernel("Oops",&fp->ptregs,mmusr);
600                         force_sig(SIGSEGV);
601                         return;
602                 }
603
604                 /* setup an ATC entry for the access about to be retried */
605                 if (!(ssw & RW) || (ssw & RM))
606                         asm volatile ("ploadw %1,%0@" : /* no outputs */
607                                       : "a" (addr), "d" (ssw));
608                 else
609                         asm volatile ("ploadr %1,%0@" : /* no outputs */
610                                       : "a" (addr), "d" (ssw));
611         }
612
613         /* Now handle the instruction fault. */
614
615         if (!(ssw & (FC|FB)))
616                 return;
617
618         if (fp->ptregs.sr & PS_S) {
619                 pr_err("Instruction fault at %#010lx\n", fp->ptregs.pc);
620         buserr:
621                 pr_err("BAD KERNEL BUSERR\n");
622                 die_if_kernel("Oops",&fp->ptregs,0);
623                 force_sig(SIGKILL);
624                 return;
625         }
626
627         /* get the fault address */
628         if (fp->ptregs.format == 10)
629                 addr = fp->ptregs.pc + 4;
630         else
631                 addr = fp->un.fmtb.baddr;
632         if (ssw & FC)
633                 addr -= 2;
634
635         if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
636                 /* Insn fault on same page as data fault.  But we
637                    should still create the ATC entry.  */
638                 goto create_atc_entry;
639
640 #ifdef DEBUG
641         asm volatile ("ptestr #1,%2@,#7,%0\n\t"
642                       "pmove %%psr,%1"
643                       : "=a&" (desc), "=m" (temp)
644                       : "a" (addr));
645         pr_debug("mmusr is %#x for addr %#lx in task %p\n",
646                 temp, addr, current);
647         pr_debug("descriptor address is 0x%p, contents %#lx\n",
648                 __va(desc), *(unsigned long *)__va(desc));
649 #else
650         asm volatile ("ptestr #1,%1@,#7\n\t"
651                       "pmove %%psr,%0"
652                       : "=m" (temp) : "a" (addr));
653 #endif
654         mmusr = temp;
655         if (mmusr & MMU_I)
656                 do_page_fault (&fp->ptregs, addr, 0);
657         else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
658                 pr_err("invalid insn access at %#lx from pc %#lx\n",
659                         addr, fp->ptregs.pc);
660                 pr_debug("Unknown SIGSEGV - 2\n");
661                 die_if_kernel("Oops",&fp->ptregs,mmusr);
662                 force_sig(SIGSEGV);
663                 return;
664         }
665
666 create_atc_entry:
667         /* setup an ATC entry for the access about to be retried */
668         asm volatile ("ploadr #2,%0@" : /* no outputs */
669                       : "a" (addr));
670 }
671 #endif /* CPU_M68020_OR_M68030 */
672 #endif /* !CONFIG_SUN3 */
673
674 #if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
675 #include <asm/mcfmmu.h>
676
677 /*
678  *      The following table converts the FS encoding of a ColdFire
679  *      exception stack frame into the error_code value needed by
680  *      do_fault.
681 */
682 static const unsigned char fs_err_code[] = {
683         0,  /* 0000 */
684         0,  /* 0001 */
685         0,  /* 0010 */
686         0,  /* 0011 */
687         1,  /* 0100 */
688         0,  /* 0101 */
689         0,  /* 0110 */
690         0,  /* 0111 */
691         2,  /* 1000 */
692         3,  /* 1001 */
693         2,  /* 1010 */
694         0,  /* 1011 */
695         1,  /* 1100 */
696         1,  /* 1101 */
697         0,  /* 1110 */
698         0   /* 1111 */
699 };
700
701 static inline void access_errorcf(unsigned int fs, struct frame *fp)
702 {
703         unsigned long mmusr, addr;
704         unsigned int err_code;
705         int need_page_fault;
706
707         mmusr = mmu_read(MMUSR);
708         addr = mmu_read(MMUAR);
709
710         /*
711          * error_code:
712          *      bit 0 == 0 means no page found, 1 means protection fault
713          *      bit 1 == 0 means read, 1 means write
714          */
715         switch (fs) {
716         case  5:  /* 0101 TLB opword X miss */
717                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 0);
718                 addr = fp->ptregs.pc;
719                 break;
720         case  6:  /* 0110 TLB extension word X miss */
721                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 1);
722                 addr = fp->ptregs.pc + sizeof(long);
723                 break;
724         case 10:  /* 1010 TLB W miss */
725                 need_page_fault = cf_tlb_miss(&fp->ptregs, 1, 1, 0);
726                 break;
727         case 14: /* 1110 TLB R miss */
728                 need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 1, 0);
729                 break;
730         default:
731                 /* 0000 Normal  */
732                 /* 0001 Reserved */
733                 /* 0010 Interrupt during debug service routine */
734                 /* 0011 Reserved */
735                 /* 0100 X Protection */
736                 /* 0111 IFP in emulator mode */
737                 /* 1000 W Protection*/
738                 /* 1001 Write error*/
739                 /* 1011 Reserved*/
740                 /* 1100 R Protection*/
741                 /* 1101 R Protection*/
742                 /* 1111 OEP in emulator mode*/
743                 need_page_fault = 1;
744                 break;
745         }
746
747         if (need_page_fault) {
748                 err_code = fs_err_code[fs];
749                 if ((fs == 13) && (mmusr & MMUSR_WF)) /* rd-mod-wr access */
750                         err_code |= 2; /* bit1 - write, bit0 - protection */
751                 do_page_fault(&fp->ptregs, addr, err_code);
752         }
753 }
754 #endif /* CONFIG_COLDFIRE CONFIG_MMU */
755
756 asmlinkage void buserr_c(struct frame *fp)
757 {
758         /* Only set esp0 if coming from user mode */
759         if (user_mode(&fp->ptregs))
760                 current->thread.esp0 = (unsigned long) fp;
761
762         pr_debug("*** Bus Error *** Format is %x\n", fp->ptregs.format);
763
764 #if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
765         if (CPU_IS_COLDFIRE) {
766                 unsigned int fs;
767                 fs = (fp->ptregs.vector & 0x3) |
768                         ((fp->ptregs.vector & 0xc00) >> 8);
769                 switch (fs) {
770                 case 0x5:
771                 case 0x6:
772                 case 0x7:
773                 case 0x9:
774                 case 0xa:
775                 case 0xd:
776                 case 0xe:
777                 case 0xf:
778                         access_errorcf(fs, fp);
779                         return;
780                 default:
781                         break;
782                 }
783         }
784 #endif /* CONFIG_COLDFIRE && CONFIG_MMU */
785
786         switch (fp->ptregs.format) {
787 #if defined (CONFIG_M68060)
788         case 4:                         /* 68060 access error */
789           access_error060 (fp);
790           break;
791 #endif
792 #if defined (CONFIG_M68040)
793         case 0x7:                       /* 68040 access error */
794           access_error040 (fp);
795           break;
796 #endif
797 #if defined (CPU_M68020_OR_M68030)
798         case 0xa:
799         case 0xb:
800           bus_error030 (fp);
801           break;
802 #endif
803         default:
804           die_if_kernel("bad frame format",&fp->ptregs,0);
805           pr_debug("Unknown SIGSEGV - 4\n");
806           force_sig(SIGSEGV);
807         }
808 }
809
810
811 static int kstack_depth_to_print = 48;
812
813 static void show_trace(unsigned long *stack, const char *loglvl)
814 {
815         unsigned long *endstack;
816         unsigned long addr;
817         int i;
818
819         printk("%sCall Trace:", loglvl);
820         addr = (unsigned long)stack + THREAD_SIZE - 1;
821         endstack = (unsigned long *)(addr & -THREAD_SIZE);
822         i = 0;
823         while (stack + 1 <= endstack) {
824                 addr = *stack++;
825                 /*
826                  * If the address is either in the text segment of the
827                  * kernel, or in the region which contains vmalloc'ed
828                  * memory, it *may* be the address of a calling
829                  * routine; if so, print it so that someone tracing
830                  * down the cause of the crash will be able to figure
831                  * out the call path that was taken.
832                  */
833                 if (__kernel_text_address(addr)) {
834 #ifndef CONFIG_KALLSYMS
835                         if (i % 5 == 0)
836                                 pr_cont("\n       ");
837 #endif
838                         pr_cont(" [<%08lx>] %pS\n", addr, (void *)addr);
839                         i++;
840                 }
841         }
842         pr_cont("\n");
843 }
844
845 void show_registers(struct pt_regs *regs)
846 {
847         struct frame *fp = (struct frame *)regs;
848         u16 c, *cp;
849         unsigned long addr;
850         int i;
851
852         print_modules();
853         pr_info("PC: [<%08lx>] %pS\n", regs->pc, (void *)regs->pc);
854         pr_info("SR: %04x  SP: %p  a2: %08lx\n", regs->sr, regs, regs->a2);
855         pr_info("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
856                regs->d0, regs->d1, regs->d2, regs->d3);
857         pr_info("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
858                regs->d4, regs->d5, regs->a0, regs->a1);
859
860         pr_info("Process %s (pid: %d, task=%p)\n",
861                 current->comm, task_pid_nr(current), current);
862         addr = (unsigned long)&fp->un;
863         pr_info("Frame format=%X ", regs->format);
864         switch (regs->format) {
865         case 0x2:
866                 pr_cont("instr addr=%08lx\n", fp->un.fmt2.iaddr);
867                 addr += sizeof(fp->un.fmt2);
868                 break;
869         case 0x3:
870                 pr_cont("eff addr=%08lx\n", fp->un.fmt3.effaddr);
871                 addr += sizeof(fp->un.fmt3);
872                 break;
873         case 0x4:
874                 if (CPU_IS_060)
875                         pr_cont("fault addr=%08lx fslw=%08lx\n",
876                                 fp->un.fmt4.effaddr, fp->un.fmt4.pc);
877                 else
878                         pr_cont("eff addr=%08lx pc=%08lx\n",
879                                 fp->un.fmt4.effaddr, fp->un.fmt4.pc);
880                 addr += sizeof(fp->un.fmt4);
881                 break;
882         case 0x7:
883                 pr_cont("eff addr=%08lx ssw=%04x faddr=%08lx\n",
884                         fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
885                 pr_info("wb 1 stat/addr/data: %04x %08lx %08lx\n",
886                         fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
887                 pr_info("wb 2 stat/addr/data: %04x %08lx %08lx\n",
888                         fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
889                 pr_info("wb 3 stat/addr/data: %04x %08lx %08lx\n",
890                         fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
891                 pr_info("push data: %08lx %08lx %08lx %08lx\n",
892                         fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
893                         fp->un.fmt7.pd3);
894                 addr += sizeof(fp->un.fmt7);
895                 break;
896         case 0x9:
897                 pr_cont("instr addr=%08lx\n", fp->un.fmt9.iaddr);
898                 addr += sizeof(fp->un.fmt9);
899                 break;
900         case 0xa:
901                 pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
902                         fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
903                         fp->un.fmta.daddr, fp->un.fmta.dobuf);
904                 addr += sizeof(fp->un.fmta);
905                 break;
906         case 0xb:
907                 pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
908                         fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
909                         fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
910                 pr_info("baddr=%08lx dibuf=%08lx ver=%x\n",
911                         fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
912                 addr += sizeof(fp->un.fmtb);
913                 break;
914         default:
915                 pr_cont("\n");
916         }
917         show_stack(NULL, (unsigned long *)addr, KERN_INFO);
918
919         pr_info("Code:");
920         cp = (u16 *)regs->pc;
921         for (i = -8; i < 16; i++) {
922                 if (get_kernel_nofault(c, cp + i) && i >= 0) {
923                         pr_cont(" Bad PC value.");
924                         break;
925                 }
926                 if (i)
927                         pr_cont(" %04x", c);
928                 else
929                         pr_cont(" <%04x>", c);
930         }
931         pr_cont("\n");
932 }
933
934 void show_stack(struct task_struct *task, unsigned long *stack,
935                 const char *loglvl)
936 {
937         unsigned long *p;
938         unsigned long *endstack;
939         int i;
940
941         if (!stack) {
942                 if (task)
943                         stack = (unsigned long *)task->thread.esp0;
944                 else
945                         stack = (unsigned long *)&stack;
946         }
947         endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
948
949         printk("%sStack from %08lx:", loglvl, (unsigned long)stack);
950         p = stack;
951         for (i = 0; i < kstack_depth_to_print; i++) {
952                 if (p + 1 > endstack)
953                         break;
954                 if (i % 8 == 0)
955                         pr_cont("\n       ");
956                 pr_cont(" %08lx", *p++);
957         }
958         pr_cont("\n");
959         show_trace(stack, loglvl);
960 }
961
962 /*
963  * The vector number returned in the frame pointer may also contain
964  * the "fs" (Fault Status) bits on ColdFire. These are in the bottom
965  * 2 bits, and upper 2 bits. So we need to mask out the real vector
966  * number before using it in comparisons. You don't need to do this on
967  * real 68k parts, but it won't hurt either.
968  */
969
970 void bad_super_trap (struct frame *fp)
971 {
972         int vector = (fp->ptregs.vector >> 2) & 0xff;
973
974         console_verbose();
975         if (vector < ARRAY_SIZE(vec_names))
976                 pr_err("*** %s ***   FORMAT=%X\n",
977                         vec_names[vector],
978                         fp->ptregs.format);
979         else
980                 pr_err("*** Exception %d ***   FORMAT=%X\n",
981                         vector, fp->ptregs.format);
982         if (vector == VEC_ADDRERR && CPU_IS_020_OR_030) {
983                 unsigned short ssw = fp->un.fmtb.ssw;
984
985                 pr_err("SSW=%#06x  ", ssw);
986
987                 if (ssw & RC)
988                         pr_err("Pipe stage C instruction fault at %#010lx\n",
989                                 (fp->ptregs.format) == 0xA ?
990                                 fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
991                 if (ssw & RB)
992                         pr_err("Pipe stage B instruction fault at %#010lx\n",
993                                 (fp->ptregs.format) == 0xA ?
994                                 fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
995                 if (ssw & DF)
996                         pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
997                                 ssw & RW ? "read" : "write",
998                                 fp->un.fmtb.daddr, space_names[ssw & DFC],
999                                 fp->ptregs.pc);
1000         }
1001         pr_err("Current process id is %d\n", task_pid_nr(current));
1002         die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
1003 }
1004
1005 asmlinkage void trap_c(struct frame *fp)
1006 {
1007         int sig, si_code;
1008         void __user *addr;
1009         int vector = (fp->ptregs.vector >> 2) & 0xff;
1010
1011         if (fp->ptregs.sr & PS_S) {
1012                 if (vector == VEC_TRACE) {
1013                         /* traced a trapping instruction on a 68020/30,
1014                          * real exception will be executed afterwards.
1015                          */
1016                         return;
1017                 }
1018 #ifdef CONFIG_MMU
1019                 if (fixup_exception(&fp->ptregs))
1020                         return;
1021 #endif
1022                 bad_super_trap(fp);
1023                 return;
1024         }
1025
1026         /* send the appropriate signal to the user program */
1027         switch (vector) {
1028             case VEC_ADDRERR:
1029                 si_code = BUS_ADRALN;
1030                 sig = SIGBUS;
1031                 break;
1032             case VEC_ILLEGAL:
1033             case VEC_LINE10:
1034             case VEC_LINE11:
1035                 si_code = ILL_ILLOPC;
1036                 sig = SIGILL;
1037                 break;
1038             case VEC_PRIV:
1039                 si_code = ILL_PRVOPC;
1040                 sig = SIGILL;
1041                 break;
1042             case VEC_COPROC:
1043                 si_code = ILL_COPROC;
1044                 sig = SIGILL;
1045                 break;
1046             case VEC_TRAP1:
1047             case VEC_TRAP2:
1048             case VEC_TRAP3:
1049             case VEC_TRAP4:
1050             case VEC_TRAP5:
1051             case VEC_TRAP6:
1052             case VEC_TRAP7:
1053             case VEC_TRAP8:
1054             case VEC_TRAP9:
1055             case VEC_TRAP10:
1056             case VEC_TRAP11:
1057             case VEC_TRAP12:
1058             case VEC_TRAP13:
1059             case VEC_TRAP14:
1060                 si_code = ILL_ILLTRP;
1061                 sig = SIGILL;
1062                 break;
1063             case VEC_FPBRUC:
1064             case VEC_FPOE:
1065             case VEC_FPNAN:
1066                 si_code = FPE_FLTINV;
1067                 sig = SIGFPE;
1068                 break;
1069             case VEC_FPIR:
1070                 si_code = FPE_FLTRES;
1071                 sig = SIGFPE;
1072                 break;
1073             case VEC_FPDIVZ:
1074                 si_code = FPE_FLTDIV;
1075                 sig = SIGFPE;
1076                 break;
1077             case VEC_FPUNDER:
1078                 si_code = FPE_FLTUND;
1079                 sig = SIGFPE;
1080                 break;
1081             case VEC_FPOVER:
1082                 si_code = FPE_FLTOVF;
1083                 sig = SIGFPE;
1084                 break;
1085             case VEC_ZERODIV:
1086                 si_code = FPE_INTDIV;
1087                 sig = SIGFPE;
1088                 break;
1089             case VEC_CHK:
1090             case VEC_TRAP:
1091                 si_code = FPE_INTOVF;
1092                 sig = SIGFPE;
1093                 break;
1094             case VEC_TRACE:             /* ptrace single step */
1095                 si_code = TRAP_TRACE;
1096                 sig = SIGTRAP;
1097                 break;
1098             case VEC_TRAP15:            /* breakpoint */
1099                 si_code = TRAP_BRKPT;
1100                 sig = SIGTRAP;
1101                 break;
1102             default:
1103                 si_code = ILL_ILLOPC;
1104                 sig = SIGILL;
1105                 break;
1106         }
1107         switch (fp->ptregs.format) {
1108             default:
1109                 addr = (void __user *) fp->ptregs.pc;
1110                 break;
1111             case 2:
1112                 addr = (void __user *) fp->un.fmt2.iaddr;
1113                 break;
1114             case 7:
1115                 addr = (void __user *) fp->un.fmt7.effaddr;
1116                 break;
1117             case 9:
1118                 addr = (void __user *) fp->un.fmt9.iaddr;
1119                 break;
1120             case 10:
1121                 addr = (void __user *) fp->un.fmta.daddr;
1122                 break;
1123             case 11:
1124                 addr = (void __user*) fp->un.fmtb.daddr;
1125                 break;
1126         }
1127         force_sig_fault(sig, si_code, addr);
1128 }
1129
1130 void die_if_kernel (char *str, struct pt_regs *fp, int nr)
1131 {
1132         if (!(fp->sr & PS_S))
1133                 return;
1134
1135         console_verbose();
1136         pr_crit("%s: %08x\n", str, nr);
1137         show_registers(fp);
1138         add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
1139         do_exit(SIGSEGV);
1140 }
1141
1142 asmlinkage void set_esp0(unsigned long ssp)
1143 {
1144         current->thread.esp0 = ssp;
1145 }
1146
1147 /*
1148  * This function is called if an error occur while accessing
1149  * user-space from the fpsp040 code.
1150  */
1151 asmlinkage void fpsp040_die(void)
1152 {
1153         force_sigsegv(SIGSEGV);
1154 }
1155
1156 #ifdef CONFIG_M68KFPU_EMU
1157 asmlinkage void fpemu_signal(int signal, int code, void *addr)
1158 {
1159         force_sig_fault(signal, code, addr);
1160 }
1161 #endif