Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/mm/fault.c | |
3 | * | |
4 | * Copyright (C) 1995 Linus Torvalds | |
5 | * Modifications for ARM processor (c) 1995-2004 Russell King | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
1da177e4 LT |
11 | #include <linux/module.h> |
12 | #include <linux/signal.h> | |
1da177e4 | 13 | #include <linux/mm.h> |
67306da6 | 14 | #include <linux/hardirq.h> |
1da177e4 | 15 | #include <linux/init.h> |
25ce1dd7 | 16 | #include <linux/kprobes.h> |
33fa9b13 | 17 | #include <linux/uaccess.h> |
252d4c27 | 18 | #include <linux/page-flags.h> |
412bb0a6 | 19 | #include <linux/sched.h> |
65cec8e3 | 20 | #include <linux/highmem.h> |
7ada189f | 21 | #include <linux/perf_event.h> |
1da177e4 | 22 | |
5a567d78 | 23 | #include <asm/exception.h> |
1da177e4 LT |
24 | #include <asm/system.h> |
25 | #include <asm/pgtable.h> | |
26 | #include <asm/tlbflush.h> | |
1da177e4 LT |
27 | |
28 | #include "fault.h" | |
29 | ||
c88d6aa7 | 30 | /* |
df297bf6 | 31 | * Fault status register encodings. We steal bit 31 for our own purposes. |
c88d6aa7 | 32 | */ |
df297bf6 | 33 | #define FSR_LNX_PF (1 << 31) |
c88d6aa7 RK |
34 | #define FSR_WRITE (1 << 11) |
35 | #define FSR_FS4 (1 << 10) | |
36 | #define FSR_FS3_0 (15) | |
37 | ||
38 | static inline int fsr_fs(unsigned int fsr) | |
39 | { | |
40 | return (fsr & FSR_FS3_0) | (fsr & FSR_FS4) >> 6; | |
41 | } | |
42 | ||
09529f7a | 43 | #ifdef CONFIG_MMU |
25ce1dd7 NP |
44 | |
45 | #ifdef CONFIG_KPROBES | |
46 | static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) | |
47 | { | |
48 | int ret = 0; | |
49 | ||
50 | if (!user_mode(regs)) { | |
51 | /* kprobe_running() needs smp_processor_id() */ | |
52 | preempt_disable(); | |
53 | if (kprobe_running() && kprobe_fault_handler(regs, fsr)) | |
54 | ret = 1; | |
55 | preempt_enable(); | |
56 | } | |
57 | ||
58 | return ret; | |
59 | } | |
60 | #else | |
61 | static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) | |
62 | { | |
63 | return 0; | |
64 | } | |
65 | #endif | |
66 | ||
1da177e4 LT |
67 | /* |
68 | * This is useful to dump out the page tables associated with | |
69 | * 'addr' in mm 'mm'. | |
70 | */ | |
71 | void show_pte(struct mm_struct *mm, unsigned long addr) | |
72 | { | |
73 | pgd_t *pgd; | |
74 | ||
75 | if (!mm) | |
76 | mm = &init_mm; | |
77 | ||
78 | printk(KERN_ALERT "pgd = %p\n", mm->pgd); | |
79 | pgd = pgd_offset(mm, addr); | |
29a38193 WD |
80 | printk(KERN_ALERT "[%08lx] *pgd=%08llx", |
81 | addr, (long long)pgd_val(*pgd)); | |
1da177e4 LT |
82 | |
83 | do { | |
516295e5 | 84 | pud_t *pud; |
1da177e4 LT |
85 | pmd_t *pmd; |
86 | pte_t *pte; | |
87 | ||
88 | if (pgd_none(*pgd)) | |
89 | break; | |
90 | ||
91 | if (pgd_bad(*pgd)) { | |
92 | printk("(bad)"); | |
93 | break; | |
94 | } | |
95 | ||
516295e5 RK |
96 | pud = pud_offset(pgd, addr); |
97 | if (PTRS_PER_PUD != 1) | |
140d5dc1 | 98 | printk(", *pud=%08llx", (long long)pud_val(*pud)); |
516295e5 RK |
99 | |
100 | if (pud_none(*pud)) | |
101 | break; | |
102 | ||
103 | if (pud_bad(*pud)) { | |
104 | printk("(bad)"); | |
105 | break; | |
106 | } | |
107 | ||
108 | pmd = pmd_offset(pud, addr); | |
da46c79a | 109 | if (PTRS_PER_PMD != 1) |
29a38193 | 110 | printk(", *pmd=%08llx", (long long)pmd_val(*pmd)); |
1da177e4 LT |
111 | |
112 | if (pmd_none(*pmd)) | |
113 | break; | |
114 | ||
115 | if (pmd_bad(*pmd)) { | |
116 | printk("(bad)"); | |
117 | break; | |
118 | } | |
119 | ||
1da177e4 | 120 | /* We must not map this if we have highmem enabled */ |
252d4c27 NP |
121 | if (PageHighMem(pfn_to_page(pmd_val(*pmd) >> PAGE_SHIFT))) |
122 | break; | |
123 | ||
1da177e4 | 124 | pte = pte_offset_map(pmd, addr); |
29a38193 WD |
125 | printk(", *pte=%08llx", (long long)pte_val(*pte)); |
126 | printk(", *ppte=%08llx", | |
127 | (long long)pte_val(pte[PTE_HWTABLE_PTRS])); | |
1da177e4 | 128 | pte_unmap(pte); |
1da177e4 LT |
129 | } while(0); |
130 | ||
131 | printk("\n"); | |
132 | } | |
09529f7a CM |
133 | #else /* CONFIG_MMU */ |
134 | void show_pte(struct mm_struct *mm, unsigned long addr) | |
135 | { } | |
136 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
137 | |
138 | /* | |
139 | * Oops. The kernel tried to access some page that wasn't present. | |
140 | */ | |
141 | static void | |
142 | __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, | |
143 | struct pt_regs *regs) | |
144 | { | |
145 | /* | |
146 | * Are we prepared to handle this kernel fault? | |
147 | */ | |
148 | if (fixup_exception(regs)) | |
149 | return; | |
150 | ||
151 | /* | |
152 | * No handler, we'll have to terminate things with extreme prejudice. | |
153 | */ | |
154 | bust_spinlocks(1); | |
155 | printk(KERN_ALERT | |
156 | "Unable to handle kernel %s at virtual address %08lx\n", | |
157 | (addr < PAGE_SIZE) ? "NULL pointer dereference" : | |
158 | "paging request", addr); | |
159 | ||
160 | show_pte(mm, addr); | |
161 | die("Oops", regs, fsr); | |
162 | bust_spinlocks(0); | |
163 | do_exit(SIGKILL); | |
164 | } | |
165 | ||
166 | /* | |
167 | * Something tried to access memory that isn't in our memory map.. | |
168 | * User mode accesses just cause a SIGSEGV | |
169 | */ | |
170 | static void | |
171 | __do_user_fault(struct task_struct *tsk, unsigned long addr, | |
2d137c24 | 172 | unsigned int fsr, unsigned int sig, int code, |
173 | struct pt_regs *regs) | |
1da177e4 LT |
174 | { |
175 | struct siginfo si; | |
176 | ||
177 | #ifdef CONFIG_DEBUG_USER | |
178 | if (user_debug & UDBG_SEGV) { | |
2d137c24 | 179 | printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n", |
180 | tsk->comm, sig, addr, fsr); | |
1da177e4 LT |
181 | show_pte(tsk->mm, addr); |
182 | show_regs(regs); | |
183 | } | |
184 | #endif | |
185 | ||
186 | tsk->thread.address = addr; | |
187 | tsk->thread.error_code = fsr; | |
188 | tsk->thread.trap_no = 14; | |
2d137c24 | 189 | si.si_signo = sig; |
1da177e4 LT |
190 | si.si_errno = 0; |
191 | si.si_code = code; | |
192 | si.si_addr = (void __user *)addr; | |
2d137c24 | 193 | force_sig_info(sig, &si, tsk); |
1da177e4 LT |
194 | } |
195 | ||
e5beac37 | 196 | void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
1da177e4 | 197 | { |
e5beac37 RK |
198 | struct task_struct *tsk = current; |
199 | struct mm_struct *mm = tsk->active_mm; | |
200 | ||
1da177e4 LT |
201 | /* |
202 | * If we are in kernel mode at this point, we | |
203 | * have no context to handle this fault with. | |
204 | */ | |
205 | if (user_mode(regs)) | |
2d137c24 | 206 | __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs); |
1da177e4 LT |
207 | else |
208 | __do_kernel_fault(mm, addr, fsr, regs); | |
209 | } | |
210 | ||
09529f7a | 211 | #ifdef CONFIG_MMU |
5c72fc5c NP |
212 | #define VM_FAULT_BADMAP 0x010000 |
213 | #define VM_FAULT_BADACCESS 0x020000 | |
1da177e4 | 214 | |
d374bf14 RK |
215 | /* |
216 | * Check that the permissions on the VMA allow for the fault which occurred. | |
217 | * If we encountered a write fault, we must have write permission, otherwise | |
218 | * we allow any permission. | |
219 | */ | |
220 | static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma) | |
221 | { | |
222 | unsigned int mask = VM_READ | VM_WRITE | VM_EXEC; | |
223 | ||
224 | if (fsr & FSR_WRITE) | |
225 | mask = VM_WRITE; | |
df297bf6 RK |
226 | if (fsr & FSR_LNX_PF) |
227 | mask = VM_EXEC; | |
d374bf14 RK |
228 | |
229 | return vma->vm_flags & mask ? false : true; | |
230 | } | |
231 | ||
232 | static int __kprobes | |
1da177e4 LT |
233 | __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, |
234 | struct task_struct *tsk) | |
235 | { | |
236 | struct vm_area_struct *vma; | |
d374bf14 | 237 | int fault; |
1da177e4 LT |
238 | |
239 | vma = find_vma(mm, addr); | |
240 | fault = VM_FAULT_BADMAP; | |
d374bf14 | 241 | if (unlikely(!vma)) |
1da177e4 | 242 | goto out; |
d374bf14 | 243 | if (unlikely(vma->vm_start > addr)) |
1da177e4 LT |
244 | goto check_stack; |
245 | ||
246 | /* | |
247 | * Ok, we have a good vm_area for this | |
248 | * memory access, so we can handle it. | |
249 | */ | |
250 | good_area: | |
d374bf14 RK |
251 | if (access_error(fsr, vma)) { |
252 | fault = VM_FAULT_BADACCESS; | |
1da177e4 | 253 | goto out; |
d374bf14 | 254 | } |
1da177e4 LT |
255 | |
256 | /* | |
b42c6344 RK |
257 | * If for any reason at all we couldn't handle the fault, make |
258 | * sure we exit gracefully rather than endlessly redo the fault. | |
1da177e4 | 259 | */ |
c88d6aa7 | 260 | fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, (fsr & FSR_WRITE) ? FAULT_FLAG_WRITE : 0); |
b42c6344 RK |
261 | if (unlikely(fault & VM_FAULT_ERROR)) |
262 | return fault; | |
83c54070 | 263 | if (fault & VM_FAULT_MAJOR) |
1da177e4 | 264 | tsk->maj_flt++; |
83c54070 | 265 | else |
1da177e4 | 266 | tsk->min_flt++; |
83c54070 | 267 | return fault; |
1da177e4 | 268 | |
1da177e4 LT |
269 | check_stack: |
270 | if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr)) | |
271 | goto good_area; | |
272 | out: | |
273 | return fault; | |
274 | } | |
275 | ||
785d3cd2 | 276 | static int __kprobes |
1da177e4 LT |
277 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
278 | { | |
279 | struct task_struct *tsk; | |
280 | struct mm_struct *mm; | |
2d137c24 | 281 | int fault, sig, code; |
1da177e4 | 282 | |
25ce1dd7 NP |
283 | if (notify_page_fault(regs, fsr)) |
284 | return 0; | |
285 | ||
1da177e4 LT |
286 | tsk = current; |
287 | mm = tsk->mm; | |
288 | ||
02fe2845 RK |
289 | /* Enable interrupts if they were enabled in the parent context. */ |
290 | if (interrupts_enabled(regs)) | |
291 | local_irq_enable(); | |
292 | ||
1da177e4 LT |
293 | /* |
294 | * If we're in an interrupt or have no user | |
295 | * context, we must not take the fault.. | |
296 | */ | |
6edaf68a | 297 | if (in_atomic() || !mm) |
1da177e4 LT |
298 | goto no_context; |
299 | ||
840ff6a4 RK |
300 | /* |
301 | * As per x86, we may deadlock here. However, since the kernel only | |
302 | * validly references user space from well defined areas of the code, | |
303 | * we can bug out early if this is from code which shouldn't. | |
304 | */ | |
305 | if (!down_read_trylock(&mm->mmap_sem)) { | |
306 | if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc)) | |
307 | goto no_context; | |
308 | down_read(&mm->mmap_sem); | |
bf456992 RK |
309 | } else { |
310 | /* | |
311 | * The above down_read_trylock() might have succeeded in | |
312 | * which case, we'll have missed the might_sleep() from | |
313 | * down_read() | |
314 | */ | |
315 | might_sleep(); | |
1d212712 ID |
316 | #ifdef CONFIG_DEBUG_VM |
317 | if (!user_mode(regs) && | |
318 | !search_exception_tables(regs->ARM_pc)) | |
319 | goto no_context; | |
320 | #endif | |
840ff6a4 RK |
321 | } |
322 | ||
1da177e4 LT |
323 | fault = __do_page_fault(mm, addr, fsr, tsk); |
324 | up_read(&mm->mmap_sem); | |
325 | ||
a8b0ca17 | 326 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); |
7ada189f | 327 | if (fault & VM_FAULT_MAJOR) |
a8b0ca17 | 328 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, addr); |
7ada189f | 329 | else if (fault & VM_FAULT_MINOR) |
a8b0ca17 | 330 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, addr); |
7ada189f | 331 | |
1da177e4 | 332 | /* |
ff2afb9d | 333 | * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR |
1da177e4 | 334 | */ |
5c72fc5c | 335 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS)))) |
1da177e4 LT |
336 | return 0; |
337 | ||
b42c6344 RK |
338 | if (fault & VM_FAULT_OOM) { |
339 | /* | |
340 | * We ran out of memory, call the OOM killer, and return to | |
341 | * userspace (which will retry the fault, or kill us if we | |
342 | * got oom-killed) | |
343 | */ | |
344 | pagefault_out_of_memory(); | |
345 | return 0; | |
346 | } | |
347 | ||
1da177e4 LT |
348 | /* |
349 | * If we are in kernel mode at this point, we | |
350 | * have no context to handle this fault with. | |
351 | */ | |
352 | if (!user_mode(regs)) | |
353 | goto no_context; | |
354 | ||
83c54070 | 355 | if (fault & VM_FAULT_SIGBUS) { |
2d137c24 | 356 | /* |
357 | * We had some memory, but were unable to | |
358 | * successfully fix up this page fault. | |
359 | */ | |
360 | sig = SIGBUS; | |
361 | code = BUS_ADRERR; | |
83c54070 | 362 | } else { |
2d137c24 | 363 | /* |
364 | * Something tried to access memory that | |
365 | * isn't in our memory map.. | |
366 | */ | |
367 | sig = SIGSEGV; | |
368 | code = fault == VM_FAULT_BADACCESS ? | |
369 | SEGV_ACCERR : SEGV_MAPERR; | |
1da177e4 | 370 | } |
1da177e4 | 371 | |
2d137c24 | 372 | __do_user_fault(tsk, addr, fsr, sig, code, regs); |
373 | return 0; | |
1da177e4 LT |
374 | |
375 | no_context: | |
376 | __do_kernel_fault(mm, addr, fsr, regs); | |
377 | return 0; | |
378 | } | |
09529f7a CM |
379 | #else /* CONFIG_MMU */ |
380 | static int | |
381 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
382 | { | |
383 | return 0; | |
384 | } | |
385 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
386 | |
387 | /* | |
388 | * First Level Translation Fault Handler | |
389 | * | |
390 | * We enter here because the first level page table doesn't contain | |
391 | * a valid entry for the address. | |
392 | * | |
393 | * If the address is in kernel space (>= TASK_SIZE), then we are | |
394 | * probably faulting in the vmalloc() area. | |
395 | * | |
396 | * If the init_task's first level page tables contains the relevant | |
397 | * entry, we copy the it to this task. If not, we send the process | |
398 | * a signal, fixup the exception, or oops the kernel. | |
399 | * | |
400 | * NOTE! We MUST NOT take any locks for this case. We may be in an | |
401 | * interrupt or a critical region, and should only copy the information | |
402 | * from the master page table, nothing more. | |
403 | */ | |
09529f7a | 404 | #ifdef CONFIG_MMU |
785d3cd2 | 405 | static int __kprobes |
1da177e4 LT |
406 | do_translation_fault(unsigned long addr, unsigned int fsr, |
407 | struct pt_regs *regs) | |
408 | { | |
1da177e4 LT |
409 | unsigned int index; |
410 | pgd_t *pgd, *pgd_k; | |
516295e5 | 411 | pud_t *pud, *pud_k; |
1da177e4 LT |
412 | pmd_t *pmd, *pmd_k; |
413 | ||
414 | if (addr < TASK_SIZE) | |
415 | return do_page_fault(addr, fsr, regs); | |
416 | ||
5e27fb78 A |
417 | if (user_mode(regs)) |
418 | goto bad_area; | |
419 | ||
1da177e4 LT |
420 | index = pgd_index(addr); |
421 | ||
422 | /* | |
423 | * FIXME: CP15 C1 is write only on ARMv3 architectures. | |
424 | */ | |
425 | pgd = cpu_get_pgd() + index; | |
426 | pgd_k = init_mm.pgd + index; | |
427 | ||
428 | if (pgd_none(*pgd_k)) | |
429 | goto bad_area; | |
1da177e4 LT |
430 | if (!pgd_present(*pgd)) |
431 | set_pgd(pgd, *pgd_k); | |
432 | ||
516295e5 RK |
433 | pud = pud_offset(pgd, addr); |
434 | pud_k = pud_offset(pgd_k, addr); | |
435 | ||
436 | if (pud_none(*pud_k)) | |
437 | goto bad_area; | |
438 | if (!pud_present(*pud)) | |
439 | set_pud(pud, *pud_k); | |
440 | ||
441 | pmd = pmd_offset(pud, addr); | |
442 | pmd_k = pmd_offset(pud_k, addr); | |
1da177e4 | 443 | |
33a9c41b KS |
444 | /* |
445 | * On ARM one Linux PGD entry contains two hardware entries (see page | |
446 | * tables layout in pgtable.h). We normally guarantee that we always | |
447 | * fill both L1 entries. But create_mapping() doesn't follow the rule. | |
448 | * It can create inidividual L1 entries, so here we have to call | |
449 | * pmd_none() check for the entry really corresponded to address, not | |
450 | * for the first of pair. | |
451 | */ | |
452 | index = (addr >> SECTION_SHIFT) & 1; | |
453 | if (pmd_none(pmd_k[index])) | |
1da177e4 LT |
454 | goto bad_area; |
455 | ||
456 | copy_pmd(pmd, pmd_k); | |
457 | return 0; | |
458 | ||
459 | bad_area: | |
e5beac37 | 460 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
461 | return 0; |
462 | } | |
09529f7a CM |
463 | #else /* CONFIG_MMU */ |
464 | static int | |
465 | do_translation_fault(unsigned long addr, unsigned int fsr, | |
466 | struct pt_regs *regs) | |
467 | { | |
468 | return 0; | |
469 | } | |
470 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
471 | |
472 | /* | |
473 | * Some section permission faults need to be handled gracefully. | |
474 | * They can happen due to a __{get,put}_user during an oops. | |
475 | */ | |
476 | static int | |
477 | do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
478 | { | |
e5beac37 | 479 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
480 | return 0; |
481 | } | |
482 | ||
483 | /* | |
484 | * This abort handler always returns "fault". | |
485 | */ | |
486 | static int | |
487 | do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
488 | { | |
489 | return 1; | |
490 | } | |
491 | ||
492 | static struct fsr_info { | |
493 | int (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs); | |
494 | int sig; | |
cfb0810e | 495 | int code; |
1da177e4 LT |
496 | const char *name; |
497 | } fsr_info[] = { | |
498 | /* | |
499 | * The following are the standard ARMv3 and ARMv4 aborts. ARMv5 | |
500 | * defines these to be "precise" aborts. | |
501 | */ | |
cfb0810e | 502 | { do_bad, SIGSEGV, 0, "vector exception" }, |
3dc91aff | 503 | { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" }, |
cfb0810e | 504 | { do_bad, SIGKILL, 0, "terminal exception" }, |
3dc91aff | 505 | { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" }, |
cfb0810e RK |
506 | { do_bad, SIGBUS, 0, "external abort on linefetch" }, |
507 | { do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" }, | |
508 | { do_bad, SIGBUS, 0, "external abort on linefetch" }, | |
509 | { do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" }, | |
510 | { do_bad, SIGBUS, 0, "external abort on non-linefetch" }, | |
511 | { do_bad, SIGSEGV, SEGV_ACCERR, "section domain fault" }, | |
512 | { do_bad, SIGBUS, 0, "external abort on non-linefetch" }, | |
513 | { do_bad, SIGSEGV, SEGV_ACCERR, "page domain fault" }, | |
514 | { do_bad, SIGBUS, 0, "external abort on translation" }, | |
515 | { do_sect_fault, SIGSEGV, SEGV_ACCERR, "section permission fault" }, | |
516 | { do_bad, SIGBUS, 0, "external abort on translation" }, | |
517 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "page permission fault" }, | |
1da177e4 LT |
518 | /* |
519 | * The following are "imprecise" aborts, which are signalled by bit | |
520 | * 10 of the FSR, and may not be recoverable. These are only | |
521 | * supported if the CPU abort handler supports bit 10. | |
522 | */ | |
cfb0810e RK |
523 | { do_bad, SIGBUS, 0, "unknown 16" }, |
524 | { do_bad, SIGBUS, 0, "unknown 17" }, | |
525 | { do_bad, SIGBUS, 0, "unknown 18" }, | |
526 | { do_bad, SIGBUS, 0, "unknown 19" }, | |
527 | { do_bad, SIGBUS, 0, "lock abort" }, /* xscale */ | |
528 | { do_bad, SIGBUS, 0, "unknown 21" }, | |
529 | { do_bad, SIGBUS, BUS_OBJERR, "imprecise external abort" }, /* xscale */ | |
530 | { do_bad, SIGBUS, 0, "unknown 23" }, | |
531 | { do_bad, SIGBUS, 0, "dcache parity error" }, /* xscale */ | |
532 | { do_bad, SIGBUS, 0, "unknown 25" }, | |
533 | { do_bad, SIGBUS, 0, "unknown 26" }, | |
534 | { do_bad, SIGBUS, 0, "unknown 27" }, | |
535 | { do_bad, SIGBUS, 0, "unknown 28" }, | |
536 | { do_bad, SIGBUS, 0, "unknown 29" }, | |
537 | { do_bad, SIGBUS, 0, "unknown 30" }, | |
538 | { do_bad, SIGBUS, 0, "unknown 31" } | |
1da177e4 LT |
539 | }; |
540 | ||
541 | void __init | |
542 | hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
6338a6aa | 543 | int sig, int code, const char *name) |
1da177e4 | 544 | { |
6338a6aa KS |
545 | if (nr < 0 || nr >= ARRAY_SIZE(fsr_info)) |
546 | BUG(); | |
547 | ||
548 | fsr_info[nr].fn = fn; | |
549 | fsr_info[nr].sig = sig; | |
550 | fsr_info[nr].code = code; | |
551 | fsr_info[nr].name = name; | |
1da177e4 LT |
552 | } |
553 | ||
554 | /* | |
555 | * Dispatch a data abort to the relevant handler. | |
556 | */ | |
7ab3f8d5 | 557 | asmlinkage void __exception |
1da177e4 LT |
558 | do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
559 | { | |
c88d6aa7 | 560 | const struct fsr_info *inf = fsr_info + fsr_fs(fsr); |
cfb0810e | 561 | struct siginfo info; |
1da177e4 | 562 | |
df297bf6 | 563 | if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs)) |
1da177e4 LT |
564 | return; |
565 | ||
566 | printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n", | |
567 | inf->name, fsr, addr); | |
cfb0810e RK |
568 | |
569 | info.si_signo = inf->sig; | |
570 | info.si_errno = 0; | |
571 | info.si_code = inf->code; | |
572 | info.si_addr = (void __user *)addr; | |
1eeb66a1 | 573 | arm_notify_die("", regs, &info, fsr, 0); |
1da177e4 LT |
574 | } |
575 | ||
d25ef8b8 KS |
576 | |
577 | static struct fsr_info ifsr_info[] = { | |
578 | { do_bad, SIGBUS, 0, "unknown 0" }, | |
579 | { do_bad, SIGBUS, 0, "unknown 1" }, | |
580 | { do_bad, SIGBUS, 0, "debug event" }, | |
581 | { do_bad, SIGSEGV, SEGV_ACCERR, "section access flag fault" }, | |
582 | { do_bad, SIGBUS, 0, "unknown 4" }, | |
583 | { do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" }, | |
584 | { do_bad, SIGSEGV, SEGV_ACCERR, "page access flag fault" }, | |
585 | { do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" }, | |
586 | { do_bad, SIGBUS, 0, "external abort on non-linefetch" }, | |
587 | { do_bad, SIGSEGV, SEGV_ACCERR, "section domain fault" }, | |
588 | { do_bad, SIGBUS, 0, "unknown 10" }, | |
589 | { do_bad, SIGSEGV, SEGV_ACCERR, "page domain fault" }, | |
590 | { do_bad, SIGBUS, 0, "external abort on translation" }, | |
591 | { do_sect_fault, SIGSEGV, SEGV_ACCERR, "section permission fault" }, | |
592 | { do_bad, SIGBUS, 0, "external abort on translation" }, | |
593 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "page permission fault" }, | |
594 | { do_bad, SIGBUS, 0, "unknown 16" }, | |
595 | { do_bad, SIGBUS, 0, "unknown 17" }, | |
596 | { do_bad, SIGBUS, 0, "unknown 18" }, | |
597 | { do_bad, SIGBUS, 0, "unknown 19" }, | |
598 | { do_bad, SIGBUS, 0, "unknown 20" }, | |
599 | { do_bad, SIGBUS, 0, "unknown 21" }, | |
600 | { do_bad, SIGBUS, 0, "unknown 22" }, | |
601 | { do_bad, SIGBUS, 0, "unknown 23" }, | |
602 | { do_bad, SIGBUS, 0, "unknown 24" }, | |
603 | { do_bad, SIGBUS, 0, "unknown 25" }, | |
604 | { do_bad, SIGBUS, 0, "unknown 26" }, | |
605 | { do_bad, SIGBUS, 0, "unknown 27" }, | |
606 | { do_bad, SIGBUS, 0, "unknown 28" }, | |
607 | { do_bad, SIGBUS, 0, "unknown 29" }, | |
608 | { do_bad, SIGBUS, 0, "unknown 30" }, | |
609 | { do_bad, SIGBUS, 0, "unknown 31" }, | |
610 | }; | |
611 | ||
3a4b5dca WD |
612 | void __init |
613 | hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
614 | int sig, int code, const char *name) | |
615 | { | |
616 | if (nr < 0 || nr >= ARRAY_SIZE(ifsr_info)) | |
617 | BUG(); | |
618 | ||
619 | ifsr_info[nr].fn = fn; | |
620 | ifsr_info[nr].sig = sig; | |
621 | ifsr_info[nr].code = code; | |
622 | ifsr_info[nr].name = name; | |
623 | } | |
624 | ||
7ab3f8d5 | 625 | asmlinkage void __exception |
4fb28474 | 626 | do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) |
1da177e4 | 627 | { |
d25ef8b8 KS |
628 | const struct fsr_info *inf = ifsr_info + fsr_fs(ifsr); |
629 | struct siginfo info; | |
630 | ||
631 | if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs)) | |
632 | return; | |
633 | ||
634 | printk(KERN_ALERT "Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n", | |
635 | inf->name, ifsr, addr); | |
636 | ||
637 | info.si_signo = inf->sig; | |
638 | info.si_errno = 0; | |
639 | info.si_code = inf->code; | |
640 | info.si_addr = (void __user *)addr; | |
641 | arm_notify_die("", regs, &info, ifsr, 0); | |
1da177e4 LT |
642 | } |
643 | ||
993bf4ec KS |
644 | static int __init exceptions_init(void) |
645 | { | |
646 | if (cpu_architecture() >= CPU_ARCH_ARMv6) { | |
647 | hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR, | |
648 | "I-cache maintenance fault"); | |
649 | } | |
650 | ||
b8ab5397 KS |
651 | if (cpu_architecture() >= CPU_ARCH_ARMv7) { |
652 | /* | |
653 | * TODO: Access flag faults introduced in ARMv6K. | |
654 | * Runtime check for 'K' extension is needed | |
655 | */ | |
656 | hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPERR, | |
657 | "section access flag fault"); | |
658 | hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPERR, | |
659 | "section access flag fault"); | |
660 | } | |
661 | ||
993bf4ec KS |
662 | return 0; |
663 | } | |
664 | ||
665 | arch_initcall(exceptions_init); |