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 | 24 | #include <asm/pgtable.h> |
9f97da78 DH |
25 | #include <asm/system_misc.h> |
26 | #include <asm/system_info.h> | |
1da177e4 | 27 | #include <asm/tlbflush.h> |
1da177e4 LT |
28 | |
29 | #include "fault.h" | |
30 | ||
09529f7a | 31 | #ifdef CONFIG_MMU |
25ce1dd7 NP |
32 | |
33 | #ifdef CONFIG_KPROBES | |
34 | static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) | |
35 | { | |
36 | int ret = 0; | |
37 | ||
38 | if (!user_mode(regs)) { | |
39 | /* kprobe_running() needs smp_processor_id() */ | |
40 | preempt_disable(); | |
41 | if (kprobe_running() && kprobe_fault_handler(regs, fsr)) | |
42 | ret = 1; | |
43 | preempt_enable(); | |
44 | } | |
45 | ||
46 | return ret; | |
47 | } | |
48 | #else | |
49 | static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) | |
50 | { | |
51 | return 0; | |
52 | } | |
53 | #endif | |
54 | ||
1da177e4 LT |
55 | /* |
56 | * This is useful to dump out the page tables associated with | |
57 | * 'addr' in mm 'mm'. | |
58 | */ | |
59 | void show_pte(struct mm_struct *mm, unsigned long addr) | |
60 | { | |
61 | pgd_t *pgd; | |
62 | ||
63 | if (!mm) | |
64 | mm = &init_mm; | |
65 | ||
66 | printk(KERN_ALERT "pgd = %p\n", mm->pgd); | |
67 | pgd = pgd_offset(mm, addr); | |
29a38193 WD |
68 | printk(KERN_ALERT "[%08lx] *pgd=%08llx", |
69 | addr, (long long)pgd_val(*pgd)); | |
1da177e4 LT |
70 | |
71 | do { | |
516295e5 | 72 | pud_t *pud; |
1da177e4 LT |
73 | pmd_t *pmd; |
74 | pte_t *pte; | |
75 | ||
76 | if (pgd_none(*pgd)) | |
77 | break; | |
78 | ||
79 | if (pgd_bad(*pgd)) { | |
80 | printk("(bad)"); | |
81 | break; | |
82 | } | |
83 | ||
516295e5 RK |
84 | pud = pud_offset(pgd, addr); |
85 | if (PTRS_PER_PUD != 1) | |
140d5dc1 | 86 | printk(", *pud=%08llx", (long long)pud_val(*pud)); |
516295e5 RK |
87 | |
88 | if (pud_none(*pud)) | |
89 | break; | |
90 | ||
91 | if (pud_bad(*pud)) { | |
92 | printk("(bad)"); | |
93 | break; | |
94 | } | |
95 | ||
96 | pmd = pmd_offset(pud, addr); | |
da46c79a | 97 | if (PTRS_PER_PMD != 1) |
29a38193 | 98 | printk(", *pmd=%08llx", (long long)pmd_val(*pmd)); |
1da177e4 LT |
99 | |
100 | if (pmd_none(*pmd)) | |
101 | break; | |
102 | ||
103 | if (pmd_bad(*pmd)) { | |
104 | printk("(bad)"); | |
105 | break; | |
106 | } | |
107 | ||
1da177e4 | 108 | /* We must not map this if we have highmem enabled */ |
252d4c27 NP |
109 | if (PageHighMem(pfn_to_page(pmd_val(*pmd) >> PAGE_SHIFT))) |
110 | break; | |
111 | ||
1da177e4 | 112 | pte = pte_offset_map(pmd, addr); |
29a38193 | 113 | printk(", *pte=%08llx", (long long)pte_val(*pte)); |
f7b8156d | 114 | #ifndef CONFIG_ARM_LPAE |
29a38193 WD |
115 | printk(", *ppte=%08llx", |
116 | (long long)pte_val(pte[PTE_HWTABLE_PTRS])); | |
f7b8156d | 117 | #endif |
1da177e4 | 118 | pte_unmap(pte); |
1da177e4 LT |
119 | } while(0); |
120 | ||
121 | printk("\n"); | |
122 | } | |
09529f7a CM |
123 | #else /* CONFIG_MMU */ |
124 | void show_pte(struct mm_struct *mm, unsigned long addr) | |
125 | { } | |
126 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
127 | |
128 | /* | |
129 | * Oops. The kernel tried to access some page that wasn't present. | |
130 | */ | |
131 | static void | |
132 | __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, | |
133 | struct pt_regs *regs) | |
134 | { | |
135 | /* | |
136 | * Are we prepared to handle this kernel fault? | |
137 | */ | |
138 | if (fixup_exception(regs)) | |
139 | return; | |
140 | ||
141 | /* | |
142 | * No handler, we'll have to terminate things with extreme prejudice. | |
143 | */ | |
144 | bust_spinlocks(1); | |
145 | printk(KERN_ALERT | |
146 | "Unable to handle kernel %s at virtual address %08lx\n", | |
147 | (addr < PAGE_SIZE) ? "NULL pointer dereference" : | |
148 | "paging request", addr); | |
149 | ||
150 | show_pte(mm, addr); | |
151 | die("Oops", regs, fsr); | |
152 | bust_spinlocks(0); | |
153 | do_exit(SIGKILL); | |
154 | } | |
155 | ||
156 | /* | |
157 | * Something tried to access memory that isn't in our memory map.. | |
158 | * User mode accesses just cause a SIGSEGV | |
159 | */ | |
160 | static void | |
161 | __do_user_fault(struct task_struct *tsk, unsigned long addr, | |
2d137c24 | 162 | unsigned int fsr, unsigned int sig, int code, |
163 | struct pt_regs *regs) | |
1da177e4 LT |
164 | { |
165 | struct siginfo si; | |
166 | ||
167 | #ifdef CONFIG_DEBUG_USER | |
f5274c2d JM |
168 | if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) || |
169 | ((user_debug & UDBG_BUS) && (sig == SIGBUS))) { | |
2d137c24 | 170 | printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n", |
171 | tsk->comm, sig, addr, fsr); | |
1da177e4 LT |
172 | show_pte(tsk->mm, addr); |
173 | show_regs(regs); | |
174 | } | |
175 | #endif | |
176 | ||
177 | tsk->thread.address = addr; | |
178 | tsk->thread.error_code = fsr; | |
179 | tsk->thread.trap_no = 14; | |
2d137c24 | 180 | si.si_signo = sig; |
1da177e4 LT |
181 | si.si_errno = 0; |
182 | si.si_code = code; | |
183 | si.si_addr = (void __user *)addr; | |
2d137c24 | 184 | force_sig_info(sig, &si, tsk); |
1da177e4 LT |
185 | } |
186 | ||
e5beac37 | 187 | void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
1da177e4 | 188 | { |
e5beac37 RK |
189 | struct task_struct *tsk = current; |
190 | struct mm_struct *mm = tsk->active_mm; | |
191 | ||
1da177e4 LT |
192 | /* |
193 | * If we are in kernel mode at this point, we | |
194 | * have no context to handle this fault with. | |
195 | */ | |
196 | if (user_mode(regs)) | |
2d137c24 | 197 | __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs); |
1da177e4 LT |
198 | else |
199 | __do_kernel_fault(mm, addr, fsr, regs); | |
200 | } | |
201 | ||
09529f7a | 202 | #ifdef CONFIG_MMU |
5c72fc5c NP |
203 | #define VM_FAULT_BADMAP 0x010000 |
204 | #define VM_FAULT_BADACCESS 0x020000 | |
1da177e4 | 205 | |
d374bf14 RK |
206 | /* |
207 | * Check that the permissions on the VMA allow for the fault which occurred. | |
208 | * If we encountered a write fault, we must have write permission, otherwise | |
209 | * we allow any permission. | |
210 | */ | |
211 | static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma) | |
212 | { | |
213 | unsigned int mask = VM_READ | VM_WRITE | VM_EXEC; | |
214 | ||
215 | if (fsr & FSR_WRITE) | |
216 | mask = VM_WRITE; | |
df297bf6 RK |
217 | if (fsr & FSR_LNX_PF) |
218 | mask = VM_EXEC; | |
d374bf14 RK |
219 | |
220 | return vma->vm_flags & mask ? false : true; | |
221 | } | |
222 | ||
223 | static int __kprobes | |
1da177e4 | 224 | __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, |
8878a539 | 225 | unsigned int flags, struct task_struct *tsk) |
1da177e4 LT |
226 | { |
227 | struct vm_area_struct *vma; | |
d374bf14 | 228 | int fault; |
1da177e4 LT |
229 | |
230 | vma = find_vma(mm, addr); | |
231 | fault = VM_FAULT_BADMAP; | |
d374bf14 | 232 | if (unlikely(!vma)) |
1da177e4 | 233 | goto out; |
d374bf14 | 234 | if (unlikely(vma->vm_start > addr)) |
1da177e4 LT |
235 | goto check_stack; |
236 | ||
237 | /* | |
238 | * Ok, we have a good vm_area for this | |
239 | * memory access, so we can handle it. | |
240 | */ | |
241 | good_area: | |
d374bf14 RK |
242 | if (access_error(fsr, vma)) { |
243 | fault = VM_FAULT_BADACCESS; | |
1da177e4 | 244 | goto out; |
d374bf14 | 245 | } |
1da177e4 | 246 | |
8878a539 | 247 | return handle_mm_fault(mm, vma, addr & PAGE_MASK, flags); |
1da177e4 | 248 | |
1da177e4 | 249 | check_stack: |
9b61a4d1 RK |
250 | /* Don't allow expansion below FIRST_USER_ADDRESS */ |
251 | if (vma->vm_flags & VM_GROWSDOWN && | |
252 | addr >= FIRST_USER_ADDRESS && !expand_stack(vma, addr)) | |
1da177e4 LT |
253 | goto good_area; |
254 | out: | |
255 | return fault; | |
256 | } | |
257 | ||
785d3cd2 | 258 | static int __kprobes |
1da177e4 LT |
259 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
260 | { | |
261 | struct task_struct *tsk; | |
262 | struct mm_struct *mm; | |
2d137c24 | 263 | int fault, sig, code; |
8878a539 KC |
264 | int write = fsr & FSR_WRITE; |
265 | unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | | |
266 | (write ? FAULT_FLAG_WRITE : 0); | |
1da177e4 | 267 | |
25ce1dd7 NP |
268 | if (notify_page_fault(regs, fsr)) |
269 | return 0; | |
270 | ||
1da177e4 LT |
271 | tsk = current; |
272 | mm = tsk->mm; | |
273 | ||
02fe2845 RK |
274 | /* Enable interrupts if they were enabled in the parent context. */ |
275 | if (interrupts_enabled(regs)) | |
276 | local_irq_enable(); | |
277 | ||
1da177e4 LT |
278 | /* |
279 | * If we're in an interrupt or have no user | |
280 | * context, we must not take the fault.. | |
281 | */ | |
6edaf68a | 282 | if (in_atomic() || !mm) |
1da177e4 LT |
283 | goto no_context; |
284 | ||
840ff6a4 RK |
285 | /* |
286 | * As per x86, we may deadlock here. However, since the kernel only | |
287 | * validly references user space from well defined areas of the code, | |
288 | * we can bug out early if this is from code which shouldn't. | |
289 | */ | |
290 | if (!down_read_trylock(&mm->mmap_sem)) { | |
291 | if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc)) | |
292 | goto no_context; | |
8878a539 | 293 | retry: |
840ff6a4 | 294 | down_read(&mm->mmap_sem); |
bf456992 RK |
295 | } else { |
296 | /* | |
297 | * The above down_read_trylock() might have succeeded in | |
298 | * which case, we'll have missed the might_sleep() from | |
299 | * down_read() | |
300 | */ | |
301 | might_sleep(); | |
1d212712 ID |
302 | #ifdef CONFIG_DEBUG_VM |
303 | if (!user_mode(regs) && | |
304 | !search_exception_tables(regs->ARM_pc)) | |
305 | goto no_context; | |
306 | #endif | |
840ff6a4 RK |
307 | } |
308 | ||
8878a539 KC |
309 | fault = __do_page_fault(mm, addr, fsr, flags, tsk); |
310 | ||
311 | /* If we need to retry but a fatal signal is pending, handle the | |
312 | * signal first. We do not need to release the mmap_sem because | |
313 | * it would already be released in __lock_page_or_retry in | |
314 | * mm/filemap.c. */ | |
315 | if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) | |
316 | return 0; | |
317 | ||
318 | /* | |
319 | * Major/minor page fault accounting is only done on the | |
320 | * initial attempt. If we go through a retry, it is extremely | |
321 | * likely that the page will be found in page cache at that point. | |
322 | */ | |
1da177e4 | 323 | |
a8b0ca17 | 324 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); |
dff2aa7a | 325 | if (!(fault & VM_FAULT_ERROR) && flags & FAULT_FLAG_ALLOW_RETRY) { |
8878a539 KC |
326 | if (fault & VM_FAULT_MAJOR) { |
327 | tsk->maj_flt++; | |
328 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, | |
329 | regs, addr); | |
330 | } else { | |
331 | tsk->min_flt++; | |
332 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, | |
333 | regs, addr); | |
334 | } | |
335 | if (fault & VM_FAULT_RETRY) { | |
336 | /* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk | |
337 | * of starvation. */ | |
338 | flags &= ~FAULT_FLAG_ALLOW_RETRY; | |
45cac65b | 339 | flags |= FAULT_FLAG_TRIED; |
8878a539 KC |
340 | goto retry; |
341 | } | |
342 | } | |
343 | ||
344 | up_read(&mm->mmap_sem); | |
7ada189f | 345 | |
1da177e4 | 346 | /* |
ff2afb9d | 347 | * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR |
1da177e4 | 348 | */ |
5c72fc5c | 349 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS)))) |
1da177e4 LT |
350 | return 0; |
351 | ||
b42c6344 RK |
352 | if (fault & VM_FAULT_OOM) { |
353 | /* | |
354 | * We ran out of memory, call the OOM killer, and return to | |
355 | * userspace (which will retry the fault, or kill us if we | |
356 | * got oom-killed) | |
357 | */ | |
358 | pagefault_out_of_memory(); | |
359 | return 0; | |
360 | } | |
361 | ||
1da177e4 LT |
362 | /* |
363 | * If we are in kernel mode at this point, we | |
364 | * have no context to handle this fault with. | |
365 | */ | |
366 | if (!user_mode(regs)) | |
367 | goto no_context; | |
368 | ||
83c54070 | 369 | if (fault & VM_FAULT_SIGBUS) { |
2d137c24 | 370 | /* |
371 | * We had some memory, but were unable to | |
372 | * successfully fix up this page fault. | |
373 | */ | |
374 | sig = SIGBUS; | |
375 | code = BUS_ADRERR; | |
83c54070 | 376 | } else { |
2d137c24 | 377 | /* |
378 | * Something tried to access memory that | |
379 | * isn't in our memory map.. | |
380 | */ | |
381 | sig = SIGSEGV; | |
382 | code = fault == VM_FAULT_BADACCESS ? | |
383 | SEGV_ACCERR : SEGV_MAPERR; | |
1da177e4 | 384 | } |
1da177e4 | 385 | |
2d137c24 | 386 | __do_user_fault(tsk, addr, fsr, sig, code, regs); |
387 | return 0; | |
1da177e4 LT |
388 | |
389 | no_context: | |
390 | __do_kernel_fault(mm, addr, fsr, regs); | |
391 | return 0; | |
392 | } | |
09529f7a CM |
393 | #else /* CONFIG_MMU */ |
394 | static int | |
395 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
396 | { | |
397 | return 0; | |
398 | } | |
399 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
400 | |
401 | /* | |
402 | * First Level Translation Fault Handler | |
403 | * | |
404 | * We enter here because the first level page table doesn't contain | |
405 | * a valid entry for the address. | |
406 | * | |
407 | * If the address is in kernel space (>= TASK_SIZE), then we are | |
408 | * probably faulting in the vmalloc() area. | |
409 | * | |
410 | * If the init_task's first level page tables contains the relevant | |
411 | * entry, we copy the it to this task. If not, we send the process | |
412 | * a signal, fixup the exception, or oops the kernel. | |
413 | * | |
414 | * NOTE! We MUST NOT take any locks for this case. We may be in an | |
415 | * interrupt or a critical region, and should only copy the information | |
416 | * from the master page table, nothing more. | |
417 | */ | |
09529f7a | 418 | #ifdef CONFIG_MMU |
785d3cd2 | 419 | static int __kprobes |
1da177e4 LT |
420 | do_translation_fault(unsigned long addr, unsigned int fsr, |
421 | struct pt_regs *regs) | |
422 | { | |
1da177e4 LT |
423 | unsigned int index; |
424 | pgd_t *pgd, *pgd_k; | |
516295e5 | 425 | pud_t *pud, *pud_k; |
1da177e4 LT |
426 | pmd_t *pmd, *pmd_k; |
427 | ||
428 | if (addr < TASK_SIZE) | |
429 | return do_page_fault(addr, fsr, regs); | |
430 | ||
5e27fb78 A |
431 | if (user_mode(regs)) |
432 | goto bad_area; | |
433 | ||
1da177e4 LT |
434 | index = pgd_index(addr); |
435 | ||
1da177e4 LT |
436 | pgd = cpu_get_pgd() + index; |
437 | pgd_k = init_mm.pgd + index; | |
438 | ||
439 | if (pgd_none(*pgd_k)) | |
440 | goto bad_area; | |
1da177e4 LT |
441 | if (!pgd_present(*pgd)) |
442 | set_pgd(pgd, *pgd_k); | |
443 | ||
516295e5 RK |
444 | pud = pud_offset(pgd, addr); |
445 | pud_k = pud_offset(pgd_k, addr); | |
446 | ||
447 | if (pud_none(*pud_k)) | |
448 | goto bad_area; | |
449 | if (!pud_present(*pud)) | |
450 | set_pud(pud, *pud_k); | |
451 | ||
452 | pmd = pmd_offset(pud, addr); | |
453 | pmd_k = pmd_offset(pud_k, addr); | |
1da177e4 | 454 | |
f7b8156d CM |
455 | #ifdef CONFIG_ARM_LPAE |
456 | /* | |
457 | * Only one hardware entry per PMD with LPAE. | |
458 | */ | |
459 | index = 0; | |
460 | #else | |
33a9c41b KS |
461 | /* |
462 | * On ARM one Linux PGD entry contains two hardware entries (see page | |
463 | * tables layout in pgtable.h). We normally guarantee that we always | |
464 | * fill both L1 entries. But create_mapping() doesn't follow the rule. | |
465 | * It can create inidividual L1 entries, so here we have to call | |
466 | * pmd_none() check for the entry really corresponded to address, not | |
467 | * for the first of pair. | |
468 | */ | |
469 | index = (addr >> SECTION_SHIFT) & 1; | |
f7b8156d | 470 | #endif |
33a9c41b | 471 | if (pmd_none(pmd_k[index])) |
1da177e4 LT |
472 | goto bad_area; |
473 | ||
474 | copy_pmd(pmd, pmd_k); | |
475 | return 0; | |
476 | ||
477 | bad_area: | |
e5beac37 | 478 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
479 | return 0; |
480 | } | |
09529f7a CM |
481 | #else /* CONFIG_MMU */ |
482 | static int | |
483 | do_translation_fault(unsigned long addr, unsigned int fsr, | |
484 | struct pt_regs *regs) | |
485 | { | |
486 | return 0; | |
487 | } | |
488 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
489 | |
490 | /* | |
491 | * Some section permission faults need to be handled gracefully. | |
492 | * They can happen due to a __{get,put}_user during an oops. | |
493 | */ | |
809e660f | 494 | #ifndef CONFIG_ARM_LPAE |
1da177e4 LT |
495 | static int |
496 | do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
497 | { | |
e5beac37 | 498 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
499 | return 0; |
500 | } | |
809e660f | 501 | #endif /* CONFIG_ARM_LPAE */ |
1da177e4 LT |
502 | |
503 | /* | |
504 | * This abort handler always returns "fault". | |
505 | */ | |
506 | static int | |
507 | do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
508 | { | |
509 | return 1; | |
510 | } | |
511 | ||
136848d4 | 512 | struct fsr_info { |
1da177e4 LT |
513 | int (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs); |
514 | int sig; | |
cfb0810e | 515 | int code; |
1da177e4 | 516 | const char *name; |
1da177e4 LT |
517 | }; |
518 | ||
136848d4 | 519 | /* FSR definition */ |
f7b8156d CM |
520 | #ifdef CONFIG_ARM_LPAE |
521 | #include "fsr-3level.c" | |
522 | #else | |
136848d4 | 523 | #include "fsr-2level.c" |
f7b8156d | 524 | #endif |
136848d4 | 525 | |
1da177e4 LT |
526 | void __init |
527 | hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
6338a6aa | 528 | int sig, int code, const char *name) |
1da177e4 | 529 | { |
6338a6aa KS |
530 | if (nr < 0 || nr >= ARRAY_SIZE(fsr_info)) |
531 | BUG(); | |
532 | ||
533 | fsr_info[nr].fn = fn; | |
534 | fsr_info[nr].sig = sig; | |
535 | fsr_info[nr].code = code; | |
536 | fsr_info[nr].name = name; | |
1da177e4 LT |
537 | } |
538 | ||
539 | /* | |
540 | * Dispatch a data abort to the relevant handler. | |
541 | */ | |
7ab3f8d5 | 542 | asmlinkage void __exception |
1da177e4 LT |
543 | do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
544 | { | |
c88d6aa7 | 545 | const struct fsr_info *inf = fsr_info + fsr_fs(fsr); |
cfb0810e | 546 | struct siginfo info; |
1da177e4 | 547 | |
df297bf6 | 548 | if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs)) |
1da177e4 LT |
549 | return; |
550 | ||
551 | printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n", | |
552 | inf->name, fsr, addr); | |
cfb0810e RK |
553 | |
554 | info.si_signo = inf->sig; | |
555 | info.si_errno = 0; | |
556 | info.si_code = inf->code; | |
557 | info.si_addr = (void __user *)addr; | |
1eeb66a1 | 558 | arm_notify_die("", regs, &info, fsr, 0); |
1da177e4 LT |
559 | } |
560 | ||
3a4b5dca WD |
561 | void __init |
562 | hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
563 | int sig, int code, const char *name) | |
564 | { | |
565 | if (nr < 0 || nr >= ARRAY_SIZE(ifsr_info)) | |
566 | BUG(); | |
567 | ||
568 | ifsr_info[nr].fn = fn; | |
569 | ifsr_info[nr].sig = sig; | |
570 | ifsr_info[nr].code = code; | |
571 | ifsr_info[nr].name = name; | |
572 | } | |
573 | ||
7ab3f8d5 | 574 | asmlinkage void __exception |
4fb28474 | 575 | do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) |
1da177e4 | 576 | { |
d25ef8b8 KS |
577 | const struct fsr_info *inf = ifsr_info + fsr_fs(ifsr); |
578 | struct siginfo info; | |
579 | ||
580 | if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs)) | |
581 | return; | |
582 | ||
583 | printk(KERN_ALERT "Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n", | |
584 | inf->name, ifsr, addr); | |
585 | ||
586 | info.si_signo = inf->sig; | |
587 | info.si_errno = 0; | |
588 | info.si_code = inf->code; | |
589 | info.si_addr = (void __user *)addr; | |
590 | arm_notify_die("", regs, &info, ifsr, 0); | |
1da177e4 LT |
591 | } |
592 | ||
f7b8156d | 593 | #ifndef CONFIG_ARM_LPAE |
993bf4ec KS |
594 | static int __init exceptions_init(void) |
595 | { | |
596 | if (cpu_architecture() >= CPU_ARCH_ARMv6) { | |
597 | hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR, | |
598 | "I-cache maintenance fault"); | |
599 | } | |
600 | ||
b8ab5397 KS |
601 | if (cpu_architecture() >= CPU_ARCH_ARMv7) { |
602 | /* | |
603 | * TODO: Access flag faults introduced in ARMv6K. | |
604 | * Runtime check for 'K' extension is needed | |
605 | */ | |
606 | hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPERR, | |
607 | "section access flag fault"); | |
608 | hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPERR, | |
609 | "section access flag fault"); | |
610 | } | |
611 | ||
993bf4ec KS |
612 | return 0; |
613 | } | |
614 | ||
615 | arch_initcall(exceptions_init); | |
f7b8156d | 616 | #endif |