diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm26/kernel/traps.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/arm26/kernel/traps.c')
-rw-r--r-- | arch/arm26/kernel/traps.c | 548 |
1 files changed, 548 insertions, 0 deletions
diff --git a/arch/arm26/kernel/traps.c b/arch/arm26/kernel/traps.c new file mode 100644 index 000000000000..f64f59022392 --- /dev/null +++ b/arch/arm26/kernel/traps.c | |||
@@ -0,0 +1,548 @@ | |||
1 | /* | ||
2 | * linux/arch/arm26/kernel/traps.c | ||
3 | * | ||
4 | * Copyright (C) 1995-2002 Russell King | ||
5 | * Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds | ||
6 | * Copyright (C) 2003 Ian Molton (ARM26) | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify | ||
9 | * it under the terms of the GNU General Public License version 2 as | ||
10 | * published by the Free Software Foundation. | ||
11 | * | ||
12 | * 'traps.c' handles hardware exceptions after we have saved some state in | ||
13 | * 'linux/arch/arm26/lib/traps.S'. Mostly a debugging aid, but will probably | ||
14 | * kill the offending process. | ||
15 | */ | ||
16 | |||
17 | #include <linux/module.h> | ||
18 | #include <linux/config.h> | ||
19 | #include <linux/types.h> | ||
20 | #include <linux/kernel.h> | ||
21 | #include <linux/signal.h> | ||
22 | #include <linux/sched.h> | ||
23 | #include <linux/mm.h> | ||
24 | #include <linux/spinlock.h> | ||
25 | #include <linux/personality.h> | ||
26 | #include <linux/ptrace.h> | ||
27 | #include <linux/elf.h> | ||
28 | #include <linux/interrupt.h> | ||
29 | #include <linux/init.h> | ||
30 | |||
31 | #include <asm/atomic.h> | ||
32 | #include <asm/io.h> | ||
33 | #include <asm/pgtable.h> | ||
34 | #include <asm/system.h> | ||
35 | #include <asm/uaccess.h> | ||
36 | #include <asm/unistd.h> | ||
37 | #include <asm/semaphore.h> | ||
38 | |||
39 | #include "ptrace.h" | ||
40 | |||
41 | extern void c_backtrace (unsigned long fp, int pmode); | ||
42 | extern void show_pte(struct mm_struct *mm, unsigned long addr); | ||
43 | |||
44 | const char *processor_modes[] = { "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" }; | ||
45 | |||
46 | static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" "*bad reason*"}; | ||
47 | |||
48 | /* | ||
49 | * Stack pointers should always be within the kernels view of | ||
50 | * physical memory. If it is not there, then we can't dump | ||
51 | * out any information relating to the stack. | ||
52 | */ | ||
53 | static int verify_stack(unsigned long sp) | ||
54 | { | ||
55 | if (sp < PAGE_OFFSET || (sp > (unsigned long)high_memory && high_memory != 0)) | ||
56 | return -EFAULT; | ||
57 | |||
58 | return 0; | ||
59 | } | ||
60 | |||
61 | /* | ||
62 | * Dump out the contents of some memory nicely... | ||
63 | */ | ||
64 | static void dump_mem(const char *str, unsigned long bottom, unsigned long top) | ||
65 | { | ||
66 | unsigned long p = bottom & ~31; | ||
67 | mm_segment_t fs; | ||
68 | int i; | ||
69 | |||
70 | /* | ||
71 | * We need to switch to kernel mode so that we can use __get_user | ||
72 | * to safely read from kernel space. Note that we now dump the | ||
73 | * code first, just in case the backtrace kills us. | ||
74 | */ | ||
75 | fs = get_fs(); | ||
76 | set_fs(KERNEL_DS); | ||
77 | |||
78 | printk("%s", str); | ||
79 | printk("(0x%08lx to 0x%08lx)\n", bottom, top); | ||
80 | |||
81 | for (p = bottom & ~31; p < top;) { | ||
82 | printk("%04lx: ", p & 0xffff); | ||
83 | |||
84 | for (i = 0; i < 8; i++, p += 4) { | ||
85 | unsigned int val; | ||
86 | |||
87 | if (p < bottom || p >= top) | ||
88 | printk(" "); | ||
89 | else { | ||
90 | __get_user(val, (unsigned long *)p); | ||
91 | printk("%08x ", val); | ||
92 | } | ||
93 | } | ||
94 | printk ("\n"); | ||
95 | } | ||
96 | |||
97 | set_fs(fs); | ||
98 | } | ||
99 | |||
100 | static void dump_instr(struct pt_regs *regs) | ||
101 | { | ||
102 | unsigned long addr = instruction_pointer(regs); | ||
103 | const int width = 8; | ||
104 | mm_segment_t fs; | ||
105 | int i; | ||
106 | |||
107 | /* | ||
108 | * We need to switch to kernel mode so that we can use __get_user | ||
109 | * to safely read from kernel space. Note that we now dump the | ||
110 | * code first, just in case the backtrace kills us. | ||
111 | */ | ||
112 | fs = get_fs(); | ||
113 | set_fs(KERNEL_DS); | ||
114 | |||
115 | printk("Code: "); | ||
116 | for (i = -4; i < 1; i++) { | ||
117 | unsigned int val, bad; | ||
118 | |||
119 | bad = __get_user(val, &((u32 *)addr)[i]); | ||
120 | |||
121 | if (!bad) | ||
122 | printk(i == 0 ? "(%0*x) " : "%0*x ", width, val); | ||
123 | else { | ||
124 | printk("bad PC value."); | ||
125 | break; | ||
126 | } | ||
127 | } | ||
128 | printk("\n"); | ||
129 | |||
130 | set_fs(fs); | ||
131 | } | ||
132 | |||
133 | /*static*/ void __dump_stack(struct task_struct *tsk, unsigned long sp) | ||
134 | { | ||
135 | dump_mem("Stack: ", sp, 8192+(unsigned long)tsk->thread_info); | ||
136 | } | ||
137 | |||
138 | void dump_stack(void) | ||
139 | { | ||
140 | #ifdef CONFIG_DEBUG_ERRORS | ||
141 | __backtrace(); | ||
142 | #endif | ||
143 | } | ||
144 | |||
145 | EXPORT_SYMBOL(dump_stack); | ||
146 | |||
147 | //FIXME - was a static fn | ||
148 | void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) | ||
149 | { | ||
150 | unsigned int fp; | ||
151 | int ok = 1; | ||
152 | |||
153 | printk("Backtrace: "); | ||
154 | fp = regs->ARM_fp; | ||
155 | if (!fp) { | ||
156 | printk("no frame pointer"); | ||
157 | ok = 0; | ||
158 | } else if (verify_stack(fp)) { | ||
159 | printk("invalid frame pointer 0x%08x", fp); | ||
160 | ok = 0; | ||
161 | } else if (fp < (unsigned long)(tsk->thread_info + 1)) | ||
162 | printk("frame pointer underflow"); | ||
163 | printk("\n"); | ||
164 | |||
165 | if (ok) | ||
166 | c_backtrace(fp, processor_mode(regs)); | ||
167 | } | ||
168 | |||
169 | /* FIXME - this is probably wrong.. */ | ||
170 | void show_stack(struct task_struct *task, unsigned long *sp) { | ||
171 | dump_mem("Stack: ", (unsigned long)sp, 8192+(unsigned long)task->thread_info); | ||
172 | } | ||
173 | |||
174 | DEFINE_SPINLOCK(die_lock); | ||
175 | |||
176 | /* | ||
177 | * This function is protected against re-entrancy. | ||
178 | */ | ||
179 | NORET_TYPE void die(const char *str, struct pt_regs *regs, int err) | ||
180 | { | ||
181 | struct task_struct *tsk = current; | ||
182 | |||
183 | console_verbose(); | ||
184 | spin_lock_irq(&die_lock); | ||
185 | |||
186 | printk("Internal error: %s: %x\n", str, err); | ||
187 | printk("CPU: %d\n", smp_processor_id()); | ||
188 | show_regs(regs); | ||
189 | printk("Process %s (pid: %d, stack limit = 0x%p)\n", | ||
190 | current->comm, current->pid, tsk->thread_info + 1); | ||
191 | |||
192 | if (!user_mode(regs) || in_interrupt()) { | ||
193 | __dump_stack(tsk, (unsigned long)(regs + 1)); | ||
194 | dump_backtrace(regs, tsk); | ||
195 | dump_instr(regs); | ||
196 | } | ||
197 | while(1); | ||
198 | spin_unlock_irq(&die_lock); | ||
199 | do_exit(SIGSEGV); | ||
200 | } | ||
201 | |||
202 | void die_if_kernel(const char *str, struct pt_regs *regs, int err) | ||
203 | { | ||
204 | if (user_mode(regs)) | ||
205 | return; | ||
206 | |||
207 | die(str, regs, err); | ||
208 | } | ||
209 | |||
210 | static DECLARE_MUTEX(undef_sem); | ||
211 | static int (*undef_hook)(struct pt_regs *); | ||
212 | |||
213 | int request_undef_hook(int (*fn)(struct pt_regs *)) | ||
214 | { | ||
215 | int ret = -EBUSY; | ||
216 | |||
217 | down(&undef_sem); | ||
218 | if (undef_hook == NULL) { | ||
219 | undef_hook = fn; | ||
220 | ret = 0; | ||
221 | } | ||
222 | up(&undef_sem); | ||
223 | |||
224 | return ret; | ||
225 | } | ||
226 | |||
227 | int release_undef_hook(int (*fn)(struct pt_regs *)) | ||
228 | { | ||
229 | int ret = -EINVAL; | ||
230 | |||
231 | down(&undef_sem); | ||
232 | if (undef_hook == fn) { | ||
233 | undef_hook = NULL; | ||
234 | ret = 0; | ||
235 | } | ||
236 | up(&undef_sem); | ||
237 | |||
238 | return ret; | ||
239 | } | ||
240 | |||
241 | static int undefined_extension(struct pt_regs *regs, unsigned int op) | ||
242 | { | ||
243 | switch (op) { | ||
244 | case 1: /* 0xde01 / 0x?7f001f0 */ | ||
245 | ptrace_break(current, regs); | ||
246 | return 0; | ||
247 | } | ||
248 | return 1; | ||
249 | } | ||
250 | |||
251 | asmlinkage void do_undefinstr(struct pt_regs *regs) | ||
252 | { | ||
253 | siginfo_t info; | ||
254 | void *pc; | ||
255 | |||
256 | regs->ARM_pc -= 4; | ||
257 | |||
258 | pc = (unsigned long *)instruction_pointer(regs); /* strip PSR */ | ||
259 | |||
260 | if (user_mode(regs)) { | ||
261 | u32 instr; | ||
262 | |||
263 | get_user(instr, (u32 *)pc); | ||
264 | |||
265 | if ((instr & 0x0fff00ff) == 0x07f000f0 && | ||
266 | undefined_extension(regs, (instr >> 8) & 255) == 0) { | ||
267 | regs->ARM_pc += 4; | ||
268 | return; | ||
269 | } | ||
270 | } else { | ||
271 | if (undef_hook && undef_hook(regs) == 0) { | ||
272 | regs->ARM_pc += 4; | ||
273 | return; | ||
274 | } | ||
275 | } | ||
276 | |||
277 | #ifdef CONFIG_DEBUG_USER | ||
278 | printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n", | ||
279 | current->comm, current->pid, pc); | ||
280 | dump_instr(regs); | ||
281 | #endif | ||
282 | |||
283 | current->thread.error_code = 0; | ||
284 | current->thread.trap_no = 6; | ||
285 | |||
286 | info.si_signo = SIGILL; | ||
287 | info.si_errno = 0; | ||
288 | info.si_code = ILL_ILLOPC; | ||
289 | info.si_addr = pc; | ||
290 | |||
291 | force_sig_info(SIGILL, &info, current); | ||
292 | |||
293 | die_if_kernel("Oops - undefined instruction", regs, 0); | ||
294 | } | ||
295 | |||
296 | asmlinkage void do_excpt(unsigned long address, struct pt_regs *regs, int mode) | ||
297 | { | ||
298 | siginfo_t info; | ||
299 | |||
300 | #ifdef CONFIG_DEBUG_USER | ||
301 | printk(KERN_INFO "%s (%d): address exception: pc=%08lx\n", | ||
302 | current->comm, current->pid, instruction_pointer(regs)); | ||
303 | dump_instr(regs); | ||
304 | #endif | ||
305 | |||
306 | current->thread.error_code = 0; | ||
307 | current->thread.trap_no = 11; | ||
308 | |||
309 | info.si_signo = SIGBUS; | ||
310 | info.si_errno = 0; | ||
311 | info.si_code = BUS_ADRERR; | ||
312 | info.si_addr = (void *)address; | ||
313 | |||
314 | force_sig_info(SIGBUS, &info, current); | ||
315 | |||
316 | die_if_kernel("Oops - address exception", regs, mode); | ||
317 | } | ||
318 | |||
319 | asmlinkage void do_unexp_fiq (struct pt_regs *regs) | ||
320 | { | ||
321 | #ifndef CONFIG_IGNORE_FIQ | ||
322 | printk("Hmm. Unexpected FIQ received, but trying to continue\n"); | ||
323 | printk("You may have a hardware problem...\n"); | ||
324 | #endif | ||
325 | } | ||
326 | |||
327 | /* | ||
328 | * bad_mode handles the impossible case in the vectors. If you see one of | ||
329 | * these, then it's extremely serious, and could mean you have buggy hardware. | ||
330 | * It never returns, and never tries to sync. We hope that we can at least | ||
331 | * dump out some state information... | ||
332 | */ | ||
333 | asmlinkage void bad_mode(struct pt_regs *regs, int reason, int proc_mode) | ||
334 | { | ||
335 | unsigned int vectors = vectors_base(); | ||
336 | |||
337 | console_verbose(); | ||
338 | |||
339 | printk(KERN_CRIT "Bad mode in %s handler detected: mode %s\n", | ||
340 | handler[reason<5?reason:4], processor_modes[proc_mode]); | ||
341 | |||
342 | /* | ||
343 | * Dump out the vectors and stub routines. Maybe a better solution | ||
344 | * would be to dump them out only if we detect that they are corrupted. | ||
345 | */ | ||
346 | dump_mem(KERN_CRIT "Vectors: ", vectors, vectors + 0x40); | ||
347 | dump_mem(KERN_CRIT "Stubs: ", vectors + 0x200, vectors + 0x4b8); | ||
348 | |||
349 | die("Oops", regs, 0); | ||
350 | local_irq_disable(); | ||
351 | panic("bad mode"); | ||
352 | } | ||
353 | |||
354 | static int bad_syscall(int n, struct pt_regs *regs) | ||
355 | { | ||
356 | struct thread_info *thread = current_thread_info(); | ||
357 | siginfo_t info; | ||
358 | |||
359 | if (current->personality != PER_LINUX && thread->exec_domain->handler) { | ||
360 | thread->exec_domain->handler(n, regs); | ||
361 | return regs->ARM_r0; | ||
362 | } | ||
363 | |||
364 | #ifdef CONFIG_DEBUG_USER | ||
365 | printk(KERN_ERR "[%d] %s: obsolete system call %08x.\n", | ||
366 | current->pid, current->comm, n); | ||
367 | dump_instr(regs); | ||
368 | #endif | ||
369 | |||
370 | info.si_signo = SIGILL; | ||
371 | info.si_errno = 0; | ||
372 | info.si_code = ILL_ILLTRP; | ||
373 | info.si_addr = (void *)instruction_pointer(regs) - 4; | ||
374 | |||
375 | force_sig_info(SIGILL, &info, current); | ||
376 | die_if_kernel("Oops", regs, n); | ||
377 | return regs->ARM_r0; | ||
378 | } | ||
379 | |||
380 | static inline void | ||
381 | do_cache_op(unsigned long start, unsigned long end, int flags) | ||
382 | { | ||
383 | struct vm_area_struct *vma; | ||
384 | |||
385 | if (end < start) | ||
386 | return; | ||
387 | |||
388 | vma = find_vma(current->active_mm, start); | ||
389 | if (vma && vma->vm_start < end) { | ||
390 | if (start < vma->vm_start) | ||
391 | start = vma->vm_start; | ||
392 | if (end > vma->vm_end) | ||
393 | end = vma->vm_end; | ||
394 | } | ||
395 | } | ||
396 | |||
397 | /* | ||
398 | * Handle all unrecognised system calls. | ||
399 | * 0x9f0000 - 0x9fffff are some more esoteric system calls | ||
400 | */ | ||
401 | #define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE) | ||
402 | asmlinkage int arm_syscall(int no, struct pt_regs *regs) | ||
403 | { | ||
404 | siginfo_t info; | ||
405 | |||
406 | if ((no >> 16) != 0x9f) | ||
407 | return bad_syscall(no, regs); | ||
408 | |||
409 | switch (no & 0xffff) { | ||
410 | case 0: /* branch through 0 */ | ||
411 | info.si_signo = SIGSEGV; | ||
412 | info.si_errno = 0; | ||
413 | info.si_code = SEGV_MAPERR; | ||
414 | info.si_addr = NULL; | ||
415 | |||
416 | force_sig_info(SIGSEGV, &info, current); | ||
417 | |||
418 | die_if_kernel("branch through zero", regs, 0); | ||
419 | return 0; | ||
420 | |||
421 | case NR(breakpoint): /* SWI BREAK_POINT */ | ||
422 | ptrace_break(current, regs); | ||
423 | return regs->ARM_r0; | ||
424 | |||
425 | case NR(cacheflush): | ||
426 | return 0; | ||
427 | |||
428 | case NR(usr26): | ||
429 | break; | ||
430 | |||
431 | default: | ||
432 | /* Calls 9f00xx..9f07ff are defined to return -ENOSYS | ||
433 | if not implemented, rather than raising SIGILL. This | ||
434 | way the calling program can gracefully determine whether | ||
435 | a feature is supported. */ | ||
436 | if (no <= 0x7ff) | ||
437 | return -ENOSYS; | ||
438 | break; | ||
439 | } | ||
440 | #ifdef CONFIG_DEBUG_USER | ||
441 | /* | ||
442 | * experience shows that these seem to indicate that | ||
443 | * something catastrophic has happened | ||
444 | */ | ||
445 | printk("[%d] %s: arm syscall %d\n", current->pid, current->comm, no); | ||
446 | dump_instr(regs); | ||
447 | if (user_mode(regs)) { | ||
448 | show_regs(regs); | ||
449 | c_backtrace(regs->ARM_fp, processor_mode(regs)); | ||
450 | } | ||
451 | #endif | ||
452 | info.si_signo = SIGILL; | ||
453 | info.si_errno = 0; | ||
454 | info.si_code = ILL_ILLTRP; | ||
455 | info.si_addr = (void *)instruction_pointer(regs) - 4; | ||
456 | |||
457 | force_sig_info(SIGILL, &info, current); | ||
458 | die_if_kernel("Oops", regs, no); | ||
459 | return 0; | ||
460 | } | ||
461 | |||
462 | void __bad_xchg(volatile void *ptr, int size) | ||
463 | { | ||
464 | printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n", | ||
465 | __builtin_return_address(0), ptr, size); | ||
466 | BUG(); | ||
467 | } | ||
468 | |||
469 | /* | ||
470 | * A data abort trap was taken, but we did not handle the instruction. | ||
471 | * Try to abort the user program, or panic if it was the kernel. | ||
472 | */ | ||
473 | asmlinkage void | ||
474 | baddataabort(int code, unsigned long instr, struct pt_regs *regs) | ||
475 | { | ||
476 | unsigned long addr = instruction_pointer(regs); | ||
477 | siginfo_t info; | ||
478 | |||
479 | #ifdef CONFIG_DEBUG_USER | ||
480 | printk(KERN_ERR "[%d] %s: bad data abort: code %d instr 0x%08lx\n", | ||
481 | current->pid, current->comm, code, instr); | ||
482 | dump_instr(regs); | ||
483 | show_pte(current->mm, addr); | ||
484 | #endif | ||
485 | |||
486 | info.si_signo = SIGILL; | ||
487 | info.si_errno = 0; | ||
488 | info.si_code = ILL_ILLOPC; | ||
489 | info.si_addr = (void *)addr; | ||
490 | |||
491 | force_sig_info(SIGILL, &info, current); | ||
492 | die_if_kernel("unknown data abort code", regs, instr); | ||
493 | } | ||
494 | |||
495 | volatile void __bug(const char *file, int line, void *data) | ||
496 | { | ||
497 | printk(KERN_CRIT"kernel BUG at %s:%d!", file, line); | ||
498 | if (data) | ||
499 | printk(KERN_CRIT" - extra data = %p", data); | ||
500 | printk("\n"); | ||
501 | *(int *)0 = 0; | ||
502 | } | ||
503 | |||
504 | void __readwrite_bug(const char *fn) | ||
505 | { | ||
506 | printk("%s called, but not implemented", fn); | ||
507 | BUG(); | ||
508 | } | ||
509 | |||
510 | void __pte_error(const char *file, int line, unsigned long val) | ||
511 | { | ||
512 | printk("%s:%d: bad pte %08lx.\n", file, line, val); | ||
513 | } | ||
514 | |||
515 | void __pmd_error(const char *file, int line, unsigned long val) | ||
516 | { | ||
517 | printk("%s:%d: bad pmd %08lx.\n", file, line, val); | ||
518 | } | ||
519 | |||
520 | void __pgd_error(const char *file, int line, unsigned long val) | ||
521 | { | ||
522 | printk("%s:%d: bad pgd %08lx.\n", file, line, val); | ||
523 | } | ||
524 | |||
525 | asmlinkage void __div0(void) | ||
526 | { | ||
527 | printk("Division by zero in kernel.\n"); | ||
528 | dump_stack(); | ||
529 | } | ||
530 | |||
531 | void abort(void) | ||
532 | { | ||
533 | BUG(); | ||
534 | |||
535 | /* if that doesn't kill us, halt */ | ||
536 | panic("Oops failed to kill thread"); | ||
537 | } | ||
538 | |||
539 | void __init trap_init(void) | ||
540 | { | ||
541 | extern void __trap_init(unsigned long); | ||
542 | unsigned long base = vectors_base(); | ||
543 | |||
544 | __trap_init(base); | ||
545 | if (base != 0) | ||
546 | printk(KERN_DEBUG "Relocating machine vectors to 0x%08lx\n", | ||
547 | base); | ||
548 | } | ||