Report that kernel is tainted if there was an OOPS
[linux-2.6.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/a.out.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 <asm/system.h>
37 #include <asm/uaccess.h>
38 #include <asm/traps.h>
39 #include <asm/pgalloc.h>
40 #include <asm/machdep.h>
41 #include <asm/siginfo.h>
42
43 /* assembler routines */
44 asmlinkage void system_call(void);
45 asmlinkage void buserr(void);
46 asmlinkage void trap(void);
47 asmlinkage void nmihandler(void);
48 #ifdef CONFIG_M68KFPU_EMU
49 asmlinkage void fpu_emu(void);
50 #endif
51
52 e_vector vectors[256] = {
53         [VEC_BUSERR]    = buserr,
54         [VEC_SYS]       = system_call,
55 };
56
57 /* nmi handler for the Amiga */
58 asm(".text\n"
59     __ALIGN_STR "\n"
60     "nmihandler: rte");
61
62 /*
63  * this must be called very early as the kernel might
64  * use some instruction that are emulated on the 060
65  */
66 void __init base_trap_init(void)
67 {
68         if(MACH_IS_SUN3X) {
69                 extern e_vector *sun3x_prom_vbr;
70
71                 __asm__ volatile ("movec %%vbr, %0" : "=r" (sun3x_prom_vbr));
72         }
73
74         /* setup the exception vector table */
75         __asm__ volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
76
77         if (CPU_IS_060) {
78                 /* set up ISP entry points */
79                 asmlinkage void unimp_vec(void) asm ("_060_isp_unimp");
80
81                 vectors[VEC_UNIMPII] = unimp_vec;
82         }
83 }
84
85 void __init trap_init (void)
86 {
87         int i;
88
89         for (i = VEC_SPUR; i <= VEC_INT7; i++)
90                 vectors[i] = bad_inthandler;
91
92         for (i = 0; i < VEC_USER; i++)
93                 if (!vectors[i])
94                         vectors[i] = trap;
95
96         for (i = VEC_USER; i < 256; i++)
97                 vectors[i] = bad_inthandler;
98
99 #ifdef CONFIG_M68KFPU_EMU
100         if (FPU_IS_EMU)
101                 vectors[VEC_LINE11] = fpu_emu;
102 #endif
103
104         if (CPU_IS_040 && !FPU_IS_EMU) {
105                 /* set up FPSP entry points */
106                 asmlinkage void dz_vec(void) asm ("dz");
107                 asmlinkage void inex_vec(void) asm ("inex");
108                 asmlinkage void ovfl_vec(void) asm ("ovfl");
109                 asmlinkage void unfl_vec(void) asm ("unfl");
110                 asmlinkage void snan_vec(void) asm ("snan");
111                 asmlinkage void operr_vec(void) asm ("operr");
112                 asmlinkage void bsun_vec(void) asm ("bsun");
113                 asmlinkage void fline_vec(void) asm ("fline");
114                 asmlinkage void unsupp_vec(void) asm ("unsupp");
115
116                 vectors[VEC_FPDIVZ] = dz_vec;
117                 vectors[VEC_FPIR] = inex_vec;
118                 vectors[VEC_FPOVER] = ovfl_vec;
119                 vectors[VEC_FPUNDER] = unfl_vec;
120                 vectors[VEC_FPNAN] = snan_vec;
121                 vectors[VEC_FPOE] = operr_vec;
122                 vectors[VEC_FPBRUC] = bsun_vec;
123                 vectors[VEC_LINE11] = fline_vec;
124                 vectors[VEC_FPUNSUP] = unsupp_vec;
125         }
126
127         if (CPU_IS_060 && !FPU_IS_EMU) {
128                 /* set up IFPSP entry points */
129                 asmlinkage void snan_vec6(void) asm ("_060_fpsp_snan");
130                 asmlinkage void operr_vec6(void) asm ("_060_fpsp_operr");
131                 asmlinkage void ovfl_vec6(void) asm ("_060_fpsp_ovfl");
132                 asmlinkage void unfl_vec6(void) asm ("_060_fpsp_unfl");
133                 asmlinkage void dz_vec6(void) asm ("_060_fpsp_dz");
134                 asmlinkage void inex_vec6(void) asm ("_060_fpsp_inex");
135                 asmlinkage void fline_vec6(void) asm ("_060_fpsp_fline");
136                 asmlinkage void unsupp_vec6(void) asm ("_060_fpsp_unsupp");
137                 asmlinkage void effadd_vec6(void) asm ("_060_fpsp_effadd");
138
139                 vectors[VEC_FPNAN] = snan_vec6;
140                 vectors[VEC_FPOE] = operr_vec6;
141                 vectors[VEC_FPOVER] = ovfl_vec6;
142                 vectors[VEC_FPUNDER] = unfl_vec6;
143                 vectors[VEC_FPDIVZ] = dz_vec6;
144                 vectors[VEC_FPIR] = inex_vec6;
145                 vectors[VEC_LINE11] = fline_vec6;
146                 vectors[VEC_FPUNSUP] = unsupp_vec6;
147                 vectors[VEC_UNIMPEA] = effadd_vec6;
148         }
149
150         /* if running on an amiga, make the NMI interrupt do nothing */
151         if (MACH_IS_AMIGA) {
152                 vectors[VEC_INT7] = nmihandler;
153         }
154 }
155
156
157 static const char *vec_names[] = {
158         [VEC_RESETSP]   = "RESET SP",
159         [VEC_RESETPC]   = "RESET PC",
160         [VEC_BUSERR]    = "BUS ERROR",
161         [VEC_ADDRERR]   = "ADDRESS ERROR",
162         [VEC_ILLEGAL]   = "ILLEGAL INSTRUCTION",
163         [VEC_ZERODIV]   = "ZERO DIVIDE",
164         [VEC_CHK]       = "CHK",
165         [VEC_TRAP]      = "TRAPcc",
166         [VEC_PRIV]      = "PRIVILEGE VIOLATION",
167         [VEC_TRACE]     = "TRACE",
168         [VEC_LINE10]    = "LINE 1010",
169         [VEC_LINE11]    = "LINE 1111",
170         [VEC_RESV12]    = "UNASSIGNED RESERVED 12",
171         [VEC_COPROC]    = "COPROCESSOR PROTOCOL VIOLATION",
172         [VEC_FORMAT]    = "FORMAT ERROR",
173         [VEC_UNINT]     = "UNINITIALIZED INTERRUPT",
174         [VEC_RESV16]    = "UNASSIGNED RESERVED 16",
175         [VEC_RESV17]    = "UNASSIGNED RESERVED 17",
176         [VEC_RESV18]    = "UNASSIGNED RESERVED 18",
177         [VEC_RESV19]    = "UNASSIGNED RESERVED 19",
178         [VEC_RESV20]    = "UNASSIGNED RESERVED 20",
179         [VEC_RESV21]    = "UNASSIGNED RESERVED 21",
180         [VEC_RESV22]    = "UNASSIGNED RESERVED 22",
181         [VEC_RESV23]    = "UNASSIGNED RESERVED 23",
182         [VEC_SPUR]      = "SPURIOUS INTERRUPT",
183         [VEC_INT1]      = "LEVEL 1 INT",
184         [VEC_INT2]      = "LEVEL 2 INT",
185         [VEC_INT3]      = "LEVEL 3 INT",
186         [VEC_INT4]      = "LEVEL 4 INT",
187         [VEC_INT5]      = "LEVEL 5 INT",
188         [VEC_INT6]      = "LEVEL 6 INT",
189         [VEC_INT7]      = "LEVEL 7 INT",
190         [VEC_SYS]       = "SYSCALL",
191         [VEC_TRAP1]     = "TRAP #1",
192         [VEC_TRAP2]     = "TRAP #2",
193         [VEC_TRAP3]     = "TRAP #3",
194         [VEC_TRAP4]     = "TRAP #4",
195         [VEC_TRAP5]     = "TRAP #5",
196         [VEC_TRAP6]     = "TRAP #6",
197         [VEC_TRAP7]     = "TRAP #7",
198         [VEC_TRAP8]     = "TRAP #8",
199         [VEC_TRAP9]     = "TRAP #9",
200         [VEC_TRAP10]    = "TRAP #10",
201         [VEC_TRAP11]    = "TRAP #11",
202         [VEC_TRAP12]    = "TRAP #12",
203         [VEC_TRAP13]    = "TRAP #13",
204         [VEC_TRAP14]    = "TRAP #14",
205         [VEC_TRAP15]    = "TRAP #15",
206         [VEC_FPBRUC]    = "FPCP BSUN",
207         [VEC_FPIR]      = "FPCP INEXACT",
208         [VEC_FPDIVZ]    = "FPCP DIV BY 0",
209         [VEC_FPUNDER]   = "FPCP UNDERFLOW",
210         [VEC_FPOE]      = "FPCP OPERAND ERROR",
211         [VEC_FPOVER]    = "FPCP OVERFLOW",
212         [VEC_FPNAN]     = "FPCP SNAN",
213         [VEC_FPUNSUP]   = "FPCP UNSUPPORTED OPERATION",
214         [VEC_MMUCFG]    = "MMU CONFIGURATION ERROR",
215         [VEC_MMUILL]    = "MMU ILLEGAL OPERATION ERROR",
216         [VEC_MMUACC]    = "MMU ACCESS LEVEL VIOLATION ERROR",
217         [VEC_RESV59]    = "UNASSIGNED RESERVED 59",
218         [VEC_UNIMPEA]   = "UNASSIGNED RESERVED 60",
219         [VEC_UNIMPII]   = "UNASSIGNED RESERVED 61",
220         [VEC_RESV62]    = "UNASSIGNED RESERVED 62",
221         [VEC_RESV63]    = "UNASSIGNED RESERVED 63",
222 };
223
224 static const char *space_names[] = {
225         [0]             = "Space 0",
226         [USER_DATA]     = "User Data",
227         [USER_PROGRAM]  = "User Program",
228 #ifndef CONFIG_SUN3
229         [3]             = "Space 3",
230 #else
231         [FC_CONTROL]    = "Control",
232 #endif
233         [4]             = "Space 4",
234         [SUPER_DATA]    = "Super Data",
235         [SUPER_PROGRAM] = "Super Program",
236         [CPU_SPACE]     = "CPU"
237 };
238
239 void die_if_kernel(char *,struct pt_regs *,int);
240 asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
241                              unsigned long error_code);
242 int send_fault_sig(struct pt_regs *regs);
243
244 asmlinkage void trap_c(struct frame *fp);
245
246 #if defined (CONFIG_M68060)
247 static inline void access_error060 (struct frame *fp)
248 {
249         unsigned long fslw = fp->un.fmt4.pc; /* is really FSLW for access error */
250
251 #ifdef DEBUG
252         printk("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
253 #endif
254
255         if (fslw & MMU060_BPE) {
256                 /* branch prediction error -> clear branch cache */
257                 __asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
258                                       "orl   #0x00400000,%/d0\n\t"
259                                       "movec %/d0,%/cacr"
260                                       : : : "d0" );
261                 /* return if there's no other error */
262                 if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
263                         return;
264         }
265
266         if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
267                 unsigned long errorcode;
268                 unsigned long addr = fp->un.fmt4.effaddr;
269
270                 if (fslw & MMU060_MA)
271                         addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
272
273                 errorcode = 1;
274                 if (fslw & MMU060_DESC_ERR) {
275                         __flush_tlb040_one(addr);
276                         errorcode = 0;
277                 }
278                 if (fslw & MMU060_W)
279                         errorcode |= 2;
280 #ifdef DEBUG
281                 printk("errorcode = %d\n", errorcode );
282 #endif
283                 do_page_fault(&fp->ptregs, addr, errorcode);
284         } else if (fslw & (MMU060_SEE)){
285                 /* Software Emulation Error.
286                  * fault during mem_read/mem_write in ifpsp060/os.S
287                  */
288                 send_fault_sig(&fp->ptregs);
289         } else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
290                    send_fault_sig(&fp->ptregs) > 0) {
291                 printk("pc=%#lx, fa=%#lx\n", fp->ptregs.pc, fp->un.fmt4.effaddr);
292                 printk( "68060 access error, fslw=%lx\n", fslw );
293                 trap_c( fp );
294         }
295 }
296 #endif /* CONFIG_M68060 */
297
298 #if defined (CONFIG_M68040)
299 static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
300 {
301         unsigned long mmusr;
302         mm_segment_t old_fs = get_fs();
303
304         set_fs(MAKE_MM_SEG(wbs));
305
306         if (iswrite)
307                 asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
308         else
309                 asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
310
311         asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
312
313         set_fs(old_fs);
314
315         return mmusr;
316 }
317
318 static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
319                                    unsigned long wbd)
320 {
321         int res = 0;
322         mm_segment_t old_fs = get_fs();
323
324         /* set_fs can not be moved, otherwise put_user() may oops */
325         set_fs(MAKE_MM_SEG(wbs));
326
327         switch (wbs & WBSIZ_040) {
328         case BA_SIZE_BYTE:
329                 res = put_user(wbd & 0xff, (char __user *)wba);
330                 break;
331         case BA_SIZE_WORD:
332                 res = put_user(wbd & 0xffff, (short __user *)wba);
333                 break;
334         case BA_SIZE_LONG:
335                 res = put_user(wbd, (int __user *)wba);
336                 break;
337         }
338
339         /* set_fs can not be moved, otherwise put_user() may oops */
340         set_fs(old_fs);
341
342
343 #ifdef DEBUG
344         printk("do_040writeback1, res=%d\n",res);
345 #endif
346
347         return res;
348 }
349
350 /* after an exception in a writeback the stack frame corresponding
351  * to that exception is discarded, set a few bits in the old frame
352  * to simulate what it should look like
353  */
354 static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
355 {
356         fp->un.fmt7.faddr = wba;
357         fp->un.fmt7.ssw = wbs & 0xff;
358         if (wba != current->thread.faddr)
359             fp->un.fmt7.ssw |= MA_040;
360 }
361
362 static inline void do_040writebacks(struct frame *fp)
363 {
364         int res = 0;
365 #if 0
366         if (fp->un.fmt7.wb1s & WBV_040)
367                 printk("access_error040: cannot handle 1st writeback. oops.\n");
368 #endif
369
370         if ((fp->un.fmt7.wb2s & WBV_040) &&
371             !(fp->un.fmt7.wb2s & WBTT_040)) {
372                 res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
373                                        fp->un.fmt7.wb2d);
374                 if (res)
375                         fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
376                 else
377                         fp->un.fmt7.wb2s = 0;
378         }
379
380         /* do the 2nd wb only if the first one was successful (except for a kernel wb) */
381         if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
382                 res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
383                                        fp->un.fmt7.wb3d);
384                 if (res)
385                     {
386                         fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
387
388                         fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
389                         fp->un.fmt7.wb3s &= (~WBV_040);
390                         fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
391                         fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
392                     }
393                 else
394                         fp->un.fmt7.wb3s = 0;
395         }
396
397         if (res)
398                 send_fault_sig(&fp->ptregs);
399 }
400
401 /*
402  * called from sigreturn(), must ensure userspace code didn't
403  * manipulate exception frame to circumvent protection, then complete
404  * pending writebacks
405  * we just clear TM2 to turn it into an userspace access
406  */
407 asmlinkage void berr_040cleanup(struct frame *fp)
408 {
409         fp->un.fmt7.wb2s &= ~4;
410         fp->un.fmt7.wb3s &= ~4;
411
412         do_040writebacks(fp);
413 }
414
415 static inline void access_error040(struct frame *fp)
416 {
417         unsigned short ssw = fp->un.fmt7.ssw;
418         unsigned long mmusr;
419
420 #ifdef DEBUG
421         printk("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
422         printk("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
423                 fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
424         printk ("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
425                 fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
426                 fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
427 #endif
428
429         if (ssw & ATC_040) {
430                 unsigned long addr = fp->un.fmt7.faddr;
431                 unsigned long errorcode;
432
433                 /*
434                  * The MMU status has to be determined AFTER the address
435                  * has been corrected if there was a misaligned access (MA).
436                  */
437                 if (ssw & MA_040)
438                         addr = (addr + 7) & -8;
439
440                 /* MMU error, get the MMUSR info for this access */
441                 mmusr = probe040(!(ssw & RW_040), addr, ssw);
442 #ifdef DEBUG
443                 printk("mmusr = %lx\n", mmusr);
444 #endif
445                 errorcode = 1;
446                 if (!(mmusr & MMU_R_040)) {
447                         /* clear the invalid atc entry */
448                         __flush_tlb040_one(addr);
449                         errorcode = 0;
450                 }
451
452                 /* despite what documentation seems to say, RMW
453                  * accesses have always both the LK and RW bits set */
454                 if (!(ssw & RW_040) || (ssw & LK_040))
455                         errorcode |= 2;
456
457                 if (do_page_fault(&fp->ptregs, addr, errorcode)) {
458 #ifdef DEBUG
459                         printk("do_page_fault() !=0 \n");
460 #endif
461                         if (user_mode(&fp->ptregs)){
462                                 /* delay writebacks after signal delivery */
463 #ifdef DEBUG
464                                 printk(".. was usermode - return\n");
465 #endif
466                                 return;
467                         }
468                         /* disable writeback into user space from kernel
469                          * (if do_page_fault didn't fix the mapping,
470                          * the writeback won't do good)
471                          */
472 #ifdef DEBUG
473                         printk(".. disabling wb2\n");
474 #endif
475                         if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
476                                 fp->un.fmt7.wb2s &= ~WBV_040;
477                 }
478         } else if (send_fault_sig(&fp->ptregs) > 0) {
479                 printk("68040 access error, ssw=%x\n", ssw);
480                 trap_c(fp);
481         }
482
483         do_040writebacks(fp);
484 }
485 #endif /* CONFIG_M68040 */
486
487 #if defined(CONFIG_SUN3)
488 #include <asm/sun3mmu.h>
489
490 extern int mmu_emu_handle_fault (unsigned long, int, int);
491
492 /* sun3 version of bus_error030 */
493
494 static inline void bus_error030 (struct frame *fp)
495 {
496         unsigned char buserr_type = sun3_get_buserr ();
497         unsigned long addr, errorcode;
498         unsigned short ssw = fp->un.fmtb.ssw;
499         extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
500
501 #ifdef DEBUG
502         if (ssw & (FC | FB))
503                 printk ("Instruction fault at %#010lx\n",
504                         ssw & FC ?
505                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
506                         :
507                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
508         if (ssw & DF)
509                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
510                         ssw & RW ? "read" : "write",
511                         fp->un.fmtb.daddr,
512                         space_names[ssw & DFC], fp->ptregs.pc);
513 #endif
514
515         /*
516          * Check if this page should be demand-mapped. This needs to go before
517          * the testing for a bad kernel-space access (demand-mapping applies
518          * to kernel accesses too).
519          */
520
521         if ((ssw & DF)
522             && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
523                 if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
524                         return;
525         }
526
527         /* Check for kernel-space pagefault (BAD). */
528         if (fp->ptregs.sr & PS_S) {
529                 /* kernel fault must be a data fault to user space */
530                 if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
531                      // try checking the kernel mappings before surrender
532                      if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
533                           return;
534                         /* instruction fault or kernel data fault! */
535                         if (ssw & (FC | FB))
536                                 printk ("Instruction fault at %#010lx\n",
537                                         fp->ptregs.pc);
538                         if (ssw & DF) {
539                                 /* was this fault incurred testing bus mappings? */
540                                 if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
541                                    (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
542                                         send_fault_sig(&fp->ptregs);
543                                         return;
544                                 }
545
546                                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
547                                         ssw & RW ? "read" : "write",
548                                         fp->un.fmtb.daddr,
549                                         space_names[ssw & DFC], fp->ptregs.pc);
550                         }
551                         printk ("BAD KERNEL BUSERR\n");
552
553                         die_if_kernel("Oops", &fp->ptregs,0);
554                         force_sig(SIGKILL, current);
555                         return;
556                 }
557         } else {
558                 /* user fault */
559                 if (!(ssw & (FC | FB)) && !(ssw & DF))
560                         /* not an instruction fault or data fault! BAD */
561                         panic ("USER BUSERR w/o instruction or data fault");
562         }
563
564
565         /* First handle the data fault, if any.  */
566         if (ssw & DF) {
567                 addr = fp->un.fmtb.daddr;
568
569 // errorcode bit 0:     0 -> no page            1 -> protection fault
570 // errorcode bit 1:     0 -> read fault         1 -> write fault
571
572 // (buserr_type & SUN3_BUSERR_PROTERR)  -> protection fault
573 // (buserr_type & SUN3_BUSERR_INVALID)  -> invalid page fault
574
575                 if (buserr_type & SUN3_BUSERR_PROTERR)
576                         errorcode = 0x01;
577                 else if (buserr_type & SUN3_BUSERR_INVALID)
578                         errorcode = 0x00;
579                 else {
580 #ifdef DEBUG
581                         printk ("*** unexpected busfault type=%#04x\n", buserr_type);
582                         printk ("invalid %s access at %#lx from pc %#lx\n",
583                                 !(ssw & RW) ? "write" : "read", addr,
584                                 fp->ptregs.pc);
585 #endif
586                         die_if_kernel ("Oops", &fp->ptregs, buserr_type);
587                         force_sig (SIGBUS, current);
588                         return;
589                 }
590
591 //todo: wtf is RM bit? --m
592                 if (!(ssw & RW) || ssw & RM)
593                         errorcode |= 0x02;
594
595                 /* Handle page fault. */
596                 do_page_fault (&fp->ptregs, addr, errorcode);
597
598                 /* Retry the data fault now. */
599                 return;
600         }
601
602         /* Now handle the instruction fault. */
603
604         /* Get the fault address. */
605         if (fp->ptregs.format == 0xA)
606                 addr = fp->ptregs.pc + 4;
607         else
608                 addr = fp->un.fmtb.baddr;
609         if (ssw & FC)
610                 addr -= 2;
611
612         if (buserr_type & SUN3_BUSERR_INVALID) {
613                 if (!mmu_emu_handle_fault (fp->un.fmtb.daddr, 1, 0))
614                         do_page_fault (&fp->ptregs, addr, 0);
615        } else {
616 #ifdef DEBUG
617                 printk ("protection fault on insn access (segv).\n");
618 #endif
619                 force_sig (SIGSEGV, current);
620        }
621 }
622 #else
623 #if defined(CPU_M68020_OR_M68030)
624 static inline void bus_error030 (struct frame *fp)
625 {
626         volatile unsigned short temp;
627         unsigned short mmusr;
628         unsigned long addr, errorcode;
629         unsigned short ssw = fp->un.fmtb.ssw;
630 #ifdef DEBUG
631         unsigned long desc;
632
633         printk ("pid = %x  ", current->pid);
634         printk ("SSW=%#06x  ", ssw);
635
636         if (ssw & (FC | FB))
637                 printk ("Instruction fault at %#010lx\n",
638                         ssw & FC ?
639                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
640                         :
641                         fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
642         if (ssw & DF)
643                 printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
644                         ssw & RW ? "read" : "write",
645                         fp->un.fmtb.daddr,
646                         space_names[ssw & DFC], fp->ptregs.pc);
647 #endif
648
649         /* ++andreas: If a data fault and an instruction fault happen
650            at the same time map in both pages.  */
651
652         /* First handle the data fault, if any.  */
653         if (ssw & DF) {
654                 addr = fp->un.fmtb.daddr;
655
656 #ifdef DEBUG
657                 asm volatile ("ptestr %3,%2@,#7,%0\n\t"
658                               "pmove %%psr,%1@"
659                               : "=a&" (desc)
660                               : "a" (&temp), "a" (addr), "d" (ssw));
661 #else
662                 asm volatile ("ptestr %2,%1@,#7\n\t"
663                               "pmove %%psr,%0@"
664                               : : "a" (&temp), "a" (addr), "d" (ssw));
665 #endif
666                 mmusr = temp;
667
668 #ifdef DEBUG
669                 printk("mmusr is %#x for addr %#lx in task %p\n",
670                        mmusr, addr, current);
671                 printk("descriptor address is %#lx, contents %#lx\n",
672                        __va(desc), *(unsigned long *)__va(desc));
673 #endif
674
675                 errorcode = (mmusr & MMU_I) ? 0 : 1;
676                 if (!(ssw & RW) || (ssw & RM))
677                         errorcode |= 2;
678
679                 if (mmusr & (MMU_I | MMU_WP)) {
680                         if (ssw & 4) {
681                                 printk("Data %s fault at %#010lx in %s (pc=%#lx)\n",
682                                        ssw & RW ? "read" : "write",
683                                        fp->un.fmtb.daddr,
684                                        space_names[ssw & DFC], fp->ptregs.pc);
685                                 goto buserr;
686                         }
687                         /* Don't try to do anything further if an exception was
688                            handled. */
689                         if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
690                                 return;
691                 } else if (!(mmusr & MMU_I)) {
692                         /* probably a 020 cas fault */
693                         if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
694                                 printk("unexpected bus error (%#x,%#x)\n", ssw, mmusr);
695                 } else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
696                         printk("invalid %s access at %#lx from pc %#lx\n",
697                                !(ssw & RW) ? "write" : "read", addr,
698                                fp->ptregs.pc);
699                         die_if_kernel("Oops",&fp->ptregs,mmusr);
700                         force_sig(SIGSEGV, current);
701                         return;
702                 } else {
703 #if 0
704                         static volatile long tlong;
705 #endif
706
707                         printk("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
708                                !(ssw & RW) ? "write" : "read", addr,
709                                fp->ptregs.pc, ssw);
710                         asm volatile ("ptestr #1,%1@,#0\n\t"
711                                       "pmove %%psr,%0@"
712                                       : /* no outputs */
713                                       : "a" (&temp), "a" (addr));
714                         mmusr = temp;
715
716                         printk ("level 0 mmusr is %#x\n", mmusr);
717 #if 0
718                         asm volatile ("pmove %%tt0,%0@"
719                                       : /* no outputs */
720                                       : "a" (&tlong));
721                         printk("tt0 is %#lx, ", tlong);
722                         asm volatile ("pmove %%tt1,%0@"
723                                       : /* no outputs */
724                                       : "a" (&tlong));
725                         printk("tt1 is %#lx\n", tlong);
726 #endif
727 #ifdef DEBUG
728                         printk("Unknown SIGSEGV - 1\n");
729 #endif
730                         die_if_kernel("Oops",&fp->ptregs,mmusr);
731                         force_sig(SIGSEGV, current);
732                         return;
733                 }
734
735                 /* setup an ATC entry for the access about to be retried */
736                 if (!(ssw & RW) || (ssw & RM))
737                         asm volatile ("ploadw %1,%0@" : /* no outputs */
738                                       : "a" (addr), "d" (ssw));
739                 else
740                         asm volatile ("ploadr %1,%0@" : /* no outputs */
741                                       : "a" (addr), "d" (ssw));
742         }
743
744         /* Now handle the instruction fault. */
745
746         if (!(ssw & (FC|FB)))
747                 return;
748
749         if (fp->ptregs.sr & PS_S) {
750                 printk("Instruction fault at %#010lx\n",
751                         fp->ptregs.pc);
752         buserr:
753                 printk ("BAD KERNEL BUSERR\n");
754                 die_if_kernel("Oops",&fp->ptregs,0);
755                 force_sig(SIGKILL, current);
756                 return;
757         }
758
759         /* get the fault address */
760         if (fp->ptregs.format == 10)
761                 addr = fp->ptregs.pc + 4;
762         else
763                 addr = fp->un.fmtb.baddr;
764         if (ssw & FC)
765                 addr -= 2;
766
767         if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
768                 /* Insn fault on same page as data fault.  But we
769                    should still create the ATC entry.  */
770                 goto create_atc_entry;
771
772 #ifdef DEBUG
773         asm volatile ("ptestr #1,%2@,#7,%0\n\t"
774                       "pmove %%psr,%1@"
775                       : "=a&" (desc)
776                       : "a" (&temp), "a" (addr));
777 #else
778         asm volatile ("ptestr #1,%1@,#7\n\t"
779                       "pmove %%psr,%0@"
780                       : : "a" (&temp), "a" (addr));
781 #endif
782         mmusr = temp;
783
784 #ifdef DEBUG
785         printk ("mmusr is %#x for addr %#lx in task %p\n",
786                 mmusr, addr, current);
787         printk ("descriptor address is %#lx, contents %#lx\n",
788                 __va(desc), *(unsigned long *)__va(desc));
789 #endif
790
791         if (mmusr & MMU_I)
792                 do_page_fault (&fp->ptregs, addr, 0);
793         else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
794                 printk ("invalid insn access at %#lx from pc %#lx\n",
795                         addr, fp->ptregs.pc);
796 #ifdef DEBUG
797                 printk("Unknown SIGSEGV - 2\n");
798 #endif
799                 die_if_kernel("Oops",&fp->ptregs,mmusr);
800                 force_sig(SIGSEGV, current);
801                 return;
802         }
803
804 create_atc_entry:
805         /* setup an ATC entry for the access about to be retried */
806         asm volatile ("ploadr #2,%0@" : /* no outputs */
807                       : "a" (addr));
808 }
809 #endif /* CPU_M68020_OR_M68030 */
810 #endif /* !CONFIG_SUN3 */
811
812 asmlinkage void buserr_c(struct frame *fp)
813 {
814         /* Only set esp0 if coming from user mode */
815         if (user_mode(&fp->ptregs))
816                 current->thread.esp0 = (unsigned long) fp;
817
818 #ifdef DEBUG
819         printk ("*** Bus Error *** Format is %x\n", fp->ptregs.format);
820 #endif
821
822         switch (fp->ptregs.format) {
823 #if defined (CONFIG_M68060)
824         case 4:                         /* 68060 access error */
825           access_error060 (fp);
826           break;
827 #endif
828 #if defined (CONFIG_M68040)
829         case 0x7:                       /* 68040 access error */
830           access_error040 (fp);
831           break;
832 #endif
833 #if defined (CPU_M68020_OR_M68030)
834         case 0xa:
835         case 0xb:
836           bus_error030 (fp);
837           break;
838 #endif
839         default:
840           die_if_kernel("bad frame format",&fp->ptregs,0);
841 #ifdef DEBUG
842           printk("Unknown SIGSEGV - 4\n");
843 #endif
844           force_sig(SIGSEGV, current);
845         }
846 }
847
848
849 static int kstack_depth_to_print = 48;
850
851 void show_trace(unsigned long *stack)
852 {
853         unsigned long *endstack;
854         unsigned long addr;
855         int i;
856
857         printk("Call Trace:");
858         addr = (unsigned long)stack + THREAD_SIZE - 1;
859         endstack = (unsigned long *)(addr & -THREAD_SIZE);
860         i = 0;
861         while (stack + 1 <= endstack) {
862                 addr = *stack++;
863                 /*
864                  * If the address is either in the text segment of the
865                  * kernel, or in the region which contains vmalloc'ed
866                  * memory, it *may* be the address of a calling
867                  * routine; if so, print it so that someone tracing
868                  * down the cause of the crash will be able to figure
869                  * out the call path that was taken.
870                  */
871                 if (__kernel_text_address(addr)) {
872 #ifndef CONFIG_KALLSYMS
873                         if (i % 5 == 0)
874                                 printk("\n       ");
875 #endif
876                         printk(" [<%08lx>]", addr);
877                         print_symbol(" %s\n", addr);
878                         i++;
879                 }
880         }
881         printk("\n");
882 }
883
884 void show_registers(struct pt_regs *regs)
885 {
886         struct frame *fp = (struct frame *)regs;
887         mm_segment_t old_fs = get_fs();
888         u16 c, *cp;
889         unsigned long addr;
890         int i;
891
892         print_modules();
893         printk("PC: [<%08lx>]",regs->pc);
894         print_symbol(" %s", regs->pc);
895         printk("\nSR: %04x  SP: %p  a2: %08lx\n",
896                regs->sr, regs, regs->a2);
897         printk("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
898                regs->d0, regs->d1, regs->d2, regs->d3);
899         printk("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
900                regs->d4, regs->d5, regs->a0, regs->a1);
901
902         printk("Process %s (pid: %d, task=%p)\n",
903                 current->comm, current->pid, current);
904         addr = (unsigned long)&fp->un;
905         printk("Frame format=%X ", regs->format);
906         switch (regs->format) {
907         case 0x2:
908                 printk("instr addr=%08lx\n", fp->un.fmt2.iaddr);
909                 addr += sizeof(fp->un.fmt2);
910                 break;
911         case 0x3:
912                 printk("eff addr=%08lx\n", fp->un.fmt3.effaddr);
913                 addr += sizeof(fp->un.fmt3);
914                 break;
915         case 0x4:
916                 printk((CPU_IS_060 ? "fault addr=%08lx fslw=%08lx\n"
917                         : "eff addr=%08lx pc=%08lx\n"),
918                         fp->un.fmt4.effaddr, fp->un.fmt4.pc);
919                 addr += sizeof(fp->un.fmt4);
920                 break;
921         case 0x7:
922                 printk("eff addr=%08lx ssw=%04x faddr=%08lx\n",
923                         fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
924                 printk("wb 1 stat/addr/data: %04x %08lx %08lx\n",
925                         fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
926                 printk("wb 2 stat/addr/data: %04x %08lx %08lx\n",
927                         fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
928                 printk("wb 3 stat/addr/data: %04x %08lx %08lx\n",
929                         fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
930                 printk("push data: %08lx %08lx %08lx %08lx\n",
931                         fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
932                         fp->un.fmt7.pd3);
933                 addr += sizeof(fp->un.fmt7);
934                 break;
935         case 0x9:
936                 printk("instr addr=%08lx\n", fp->un.fmt9.iaddr);
937                 addr += sizeof(fp->un.fmt9);
938                 break;
939         case 0xa:
940                 printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
941                         fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
942                         fp->un.fmta.daddr, fp->un.fmta.dobuf);
943                 addr += sizeof(fp->un.fmta);
944                 break;
945         case 0xb:
946                 printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
947                         fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
948                         fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
949                 printk("baddr=%08lx dibuf=%08lx ver=%x\n",
950                         fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
951                 addr += sizeof(fp->un.fmtb);
952                 break;
953         default:
954                 printk("\n");
955         }
956         show_stack(NULL, (unsigned long *)addr);
957
958         printk("Code:");
959         set_fs(KERNEL_DS);
960         cp = (u16 *)regs->pc;
961         for (i = -8; i < 16; i++) {
962                 if (get_user(c, cp + i) && i >= 0) {
963                         printk(" Bad PC value.");
964                         break;
965                 }
966                 printk(i ? " %04x" : " <%04x>", c);
967         }
968         set_fs(old_fs);
969         printk ("\n");
970 }
971
972 void show_stack(struct task_struct *task, unsigned long *stack)
973 {
974         unsigned long *p;
975         unsigned long *endstack;
976         int i;
977
978         if (!stack) {
979                 if (task)
980                         stack = (unsigned long *)task->thread.esp0;
981                 else
982                         stack = (unsigned long *)&stack;
983         }
984         endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
985
986         printk("Stack from %08lx:", (unsigned long)stack);
987         p = stack;
988         for (i = 0; i < kstack_depth_to_print; i++) {
989                 if (p + 1 > endstack)
990                         break;
991                 if (i % 8 == 0)
992                         printk("\n       ");
993                 printk(" %08lx", *p++);
994         }
995         printk("\n");
996         show_trace(stack);
997 }
998
999 /*
1000  * The architecture-independent backtrace generator
1001  */
1002 void dump_stack(void)
1003 {
1004         unsigned long stack;
1005
1006         show_trace(&stack);
1007 }
1008
1009 EXPORT_SYMBOL(dump_stack);
1010
1011 void bad_super_trap (struct frame *fp)
1012 {
1013         console_verbose();
1014         if (fp->ptregs.vector < 4 * ARRAY_SIZE(vec_names))
1015                 printk ("*** %s ***   FORMAT=%X\n",
1016                         vec_names[(fp->ptregs.vector) >> 2],
1017                         fp->ptregs.format);
1018         else
1019                 printk ("*** Exception %d ***   FORMAT=%X\n",
1020                         (fp->ptregs.vector) >> 2,
1021                         fp->ptregs.format);
1022         if (fp->ptregs.vector >> 2 == VEC_ADDRERR && CPU_IS_020_OR_030) {
1023                 unsigned short ssw = fp->un.fmtb.ssw;
1024
1025                 printk ("SSW=%#06x  ", ssw);
1026
1027                 if (ssw & RC)
1028                         printk ("Pipe stage C instruction fault at %#010lx\n",
1029                                 (fp->ptregs.format) == 0xA ?
1030                                 fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
1031                 if (ssw & RB)
1032                         printk ("Pipe stage B instruction fault at %#010lx\n",
1033                                 (fp->ptregs.format) == 0xA ?
1034                                 fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
1035                 if (ssw & DF)
1036                         printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
1037                                 ssw & RW ? "read" : "write",
1038                                 fp->un.fmtb.daddr, space_names[ssw & DFC],
1039                                 fp->ptregs.pc);
1040         }
1041         printk ("Current process id is %d\n", current->pid);
1042         die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
1043 }
1044
1045 asmlinkage void trap_c(struct frame *fp)
1046 {
1047         int sig;
1048         siginfo_t info;
1049
1050         if (fp->ptregs.sr & PS_S) {
1051                 if ((fp->ptregs.vector >> 2) == VEC_TRACE) {
1052                         /* traced a trapping instruction */
1053                         current->ptrace |= PT_DTRACE;
1054                 } else
1055                         bad_super_trap(fp);
1056                 return;
1057         }
1058
1059         /* send the appropriate signal to the user program */
1060         switch ((fp->ptregs.vector) >> 2) {
1061             case VEC_ADDRERR:
1062                 info.si_code = BUS_ADRALN;
1063                 sig = SIGBUS;
1064                 break;
1065             case VEC_ILLEGAL:
1066             case VEC_LINE10:
1067             case VEC_LINE11:
1068                 info.si_code = ILL_ILLOPC;
1069                 sig = SIGILL;
1070                 break;
1071             case VEC_PRIV:
1072                 info.si_code = ILL_PRVOPC;
1073                 sig = SIGILL;
1074                 break;
1075             case VEC_COPROC:
1076                 info.si_code = ILL_COPROC;
1077                 sig = SIGILL;
1078                 break;
1079             case VEC_TRAP1:
1080             case VEC_TRAP2:
1081             case VEC_TRAP3:
1082             case VEC_TRAP4:
1083             case VEC_TRAP5:
1084             case VEC_TRAP6:
1085             case VEC_TRAP7:
1086             case VEC_TRAP8:
1087             case VEC_TRAP9:
1088             case VEC_TRAP10:
1089             case VEC_TRAP11:
1090             case VEC_TRAP12:
1091             case VEC_TRAP13:
1092             case VEC_TRAP14:
1093                 info.si_code = ILL_ILLTRP;
1094                 sig = SIGILL;
1095                 break;
1096             case VEC_FPBRUC:
1097             case VEC_FPOE:
1098             case VEC_FPNAN:
1099                 info.si_code = FPE_FLTINV;
1100                 sig = SIGFPE;
1101                 break;
1102             case VEC_FPIR:
1103                 info.si_code = FPE_FLTRES;
1104                 sig = SIGFPE;
1105                 break;
1106             case VEC_FPDIVZ:
1107                 info.si_code = FPE_FLTDIV;
1108                 sig = SIGFPE;
1109                 break;
1110             case VEC_FPUNDER:
1111                 info.si_code = FPE_FLTUND;
1112                 sig = SIGFPE;
1113                 break;
1114             case VEC_FPOVER:
1115                 info.si_code = FPE_FLTOVF;
1116                 sig = SIGFPE;
1117                 break;
1118             case VEC_ZERODIV:
1119                 info.si_code = FPE_INTDIV;
1120                 sig = SIGFPE;
1121                 break;
1122             case VEC_CHK:
1123             case VEC_TRAP:
1124                 info.si_code = FPE_INTOVF;
1125                 sig = SIGFPE;
1126                 break;
1127             case VEC_TRACE:             /* ptrace single step */
1128                 info.si_code = TRAP_TRACE;
1129                 sig = SIGTRAP;
1130                 break;
1131             case VEC_TRAP15:            /* breakpoint */
1132                 info.si_code = TRAP_BRKPT;
1133                 sig = SIGTRAP;
1134                 break;
1135             default:
1136                 info.si_code = ILL_ILLOPC;
1137                 sig = SIGILL;
1138                 break;
1139         }
1140         info.si_signo = sig;
1141         info.si_errno = 0;
1142         switch (fp->ptregs.format) {
1143             default:
1144                 info.si_addr = (void *) fp->ptregs.pc;
1145                 break;
1146             case 2:
1147                 info.si_addr = (void *) fp->un.fmt2.iaddr;
1148                 break;
1149             case 7:
1150                 info.si_addr = (void *) fp->un.fmt7.effaddr;
1151                 break;
1152             case 9:
1153                 info.si_addr = (void *) fp->un.fmt9.iaddr;
1154                 break;
1155             case 10:
1156                 info.si_addr = (void *) fp->un.fmta.daddr;
1157                 break;
1158             case 11:
1159                 info.si_addr = (void *) fp->un.fmtb.daddr;
1160                 break;
1161         }
1162         force_sig_info (sig, &info, current);
1163 }
1164
1165 void die_if_kernel (char *str, struct pt_regs *fp, int nr)
1166 {
1167         if (!(fp->sr & PS_S))
1168                 return;
1169
1170         console_verbose();
1171         printk("%s: %08x\n",str,nr);
1172         show_registers(fp);
1173         add_taint(TAINT_DIE);
1174         do_exit(SIGSEGV);
1175 }
1176
1177 /*
1178  * This function is called if an error occur while accessing
1179  * user-space from the fpsp040 code.
1180  */
1181 asmlinkage void fpsp040_die(void)
1182 {
1183         do_exit(SIGSEGV);
1184 }
1185
1186 #ifdef CONFIG_M68KFPU_EMU
1187 asmlinkage void fpemu_signal(int signal, int code, void *addr)
1188 {
1189         siginfo_t info;
1190
1191         info.si_signo = signal;
1192         info.si_errno = 0;
1193         info.si_code = code;
1194         info.si_addr = addr;
1195         force_sig_info(signal, &info, current);
1196 }
1197 #endif