Commit | Line | Data |
---|---|---|
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 | ||
4ed89f22 | 66 | pr_alert("pgd = %p\n", mm->pgd); |
1da177e4 | 67 | pgd = pgd_offset(mm, addr); |
4ed89f22 | 68 | pr_alert("[%08lx] *pgd=%08llx", |
29a38193 | 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)) { | |
4ed89f22 | 80 | pr_cont("(bad)"); |
1da177e4 LT |
81 | break; |
82 | } | |
83 | ||
516295e5 RK |
84 | pud = pud_offset(pgd, addr); |
85 | if (PTRS_PER_PUD != 1) | |
4ed89f22 | 86 | pr_cont(", *pud=%08llx", (long long)pud_val(*pud)); |
516295e5 RK |
87 | |
88 | if (pud_none(*pud)) | |
89 | break; | |
90 | ||
91 | if (pud_bad(*pud)) { | |
4ed89f22 | 92 | pr_cont("(bad)"); |
516295e5 RK |
93 | break; |
94 | } | |
95 | ||
96 | pmd = pmd_offset(pud, addr); | |
da46c79a | 97 | if (PTRS_PER_PMD != 1) |
4ed89f22 | 98 | pr_cont(", *pmd=%08llx", (long long)pmd_val(*pmd)); |
1da177e4 LT |
99 | |
100 | if (pmd_none(*pmd)) | |
101 | break; | |
102 | ||
103 | if (pmd_bad(*pmd)) { | |
4ed89f22 | 104 | pr_cont("(bad)"); |
1da177e4 LT |
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); |
4ed89f22 | 113 | pr_cont(", *pte=%08llx", (long long)pte_val(*pte)); |
f7b8156d | 114 | #ifndef CONFIG_ARM_LPAE |
4ed89f22 | 115 | pr_cont(", *ppte=%08llx", |
29a38193 | 116 | (long long)pte_val(pte[PTE_HWTABLE_PTRS])); |
f7b8156d | 117 | #endif |
1da177e4 | 118 | pte_unmap(pte); |
1da177e4 LT |
119 | } while(0); |
120 | ||
4ed89f22 | 121 | pr_cont("\n"); |
1da177e4 | 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); | |
4ed89f22 RK |
145 | pr_alert("Unable to handle kernel %s at virtual address %08lx\n", |
146 | (addr < PAGE_SIZE) ? "NULL pointer dereference" : | |
147 | "paging request", addr); | |
1da177e4 LT |
148 | |
149 | show_pte(mm, addr); | |
150 | die("Oops", regs, fsr); | |
151 | bust_spinlocks(0); | |
152 | do_exit(SIGKILL); | |
153 | } | |
154 | ||
155 | /* | |
156 | * Something tried to access memory that isn't in our memory map.. | |
157 | * User mode accesses just cause a SIGSEGV | |
158 | */ | |
159 | static void | |
160 | __do_user_fault(struct task_struct *tsk, unsigned long addr, | |
2d137c24 | 161 | unsigned int fsr, unsigned int sig, int code, |
162 | struct pt_regs *regs) | |
1da177e4 LT |
163 | { |
164 | struct siginfo si; | |
165 | ||
166 | #ifdef CONFIG_DEBUG_USER | |
f5274c2d JM |
167 | if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) || |
168 | ((user_debug & UDBG_BUS) && (sig == SIGBUS))) { | |
2d137c24 | 169 | printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n", |
170 | tsk->comm, sig, addr, fsr); | |
1da177e4 LT |
171 | show_pte(tsk->mm, addr); |
172 | show_regs(regs); | |
173 | } | |
174 | #endif | |
175 | ||
176 | tsk->thread.address = addr; | |
177 | tsk->thread.error_code = fsr; | |
178 | tsk->thread.trap_no = 14; | |
2d137c24 | 179 | si.si_signo = sig; |
1da177e4 LT |
180 | si.si_errno = 0; |
181 | si.si_code = code; | |
182 | si.si_addr = (void __user *)addr; | |
2d137c24 | 183 | force_sig_info(sig, &si, tsk); |
1da177e4 LT |
184 | } |
185 | ||
e5beac37 | 186 | void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
1da177e4 | 187 | { |
e5beac37 RK |
188 | struct task_struct *tsk = current; |
189 | struct mm_struct *mm = tsk->active_mm; | |
190 | ||
1da177e4 LT |
191 | /* |
192 | * If we are in kernel mode at this point, we | |
193 | * have no context to handle this fault with. | |
194 | */ | |
195 | if (user_mode(regs)) | |
2d137c24 | 196 | __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs); |
1da177e4 LT |
197 | else |
198 | __do_kernel_fault(mm, addr, fsr, regs); | |
199 | } | |
200 | ||
09529f7a | 201 | #ifdef CONFIG_MMU |
5c72fc5c NP |
202 | #define VM_FAULT_BADMAP 0x010000 |
203 | #define VM_FAULT_BADACCESS 0x020000 | |
1da177e4 | 204 | |
d374bf14 RK |
205 | /* |
206 | * Check that the permissions on the VMA allow for the fault which occurred. | |
207 | * If we encountered a write fault, we must have write permission, otherwise | |
208 | * we allow any permission. | |
209 | */ | |
210 | static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma) | |
211 | { | |
212 | unsigned int mask = VM_READ | VM_WRITE | VM_EXEC; | |
213 | ||
214 | if (fsr & FSR_WRITE) | |
215 | mask = VM_WRITE; | |
df297bf6 RK |
216 | if (fsr & FSR_LNX_PF) |
217 | mask = VM_EXEC; | |
d374bf14 RK |
218 | |
219 | return vma->vm_flags & mask ? false : true; | |
220 | } | |
221 | ||
222 | static int __kprobes | |
1da177e4 | 223 | __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, |
8878a539 | 224 | unsigned int flags, struct task_struct *tsk) |
1da177e4 LT |
225 | { |
226 | struct vm_area_struct *vma; | |
d374bf14 | 227 | int fault; |
1da177e4 LT |
228 | |
229 | vma = find_vma(mm, addr); | |
230 | fault = VM_FAULT_BADMAP; | |
d374bf14 | 231 | if (unlikely(!vma)) |
1da177e4 | 232 | goto out; |
d374bf14 | 233 | if (unlikely(vma->vm_start > addr)) |
1da177e4 LT |
234 | goto check_stack; |
235 | ||
236 | /* | |
237 | * Ok, we have a good vm_area for this | |
238 | * memory access, so we can handle it. | |
239 | */ | |
240 | good_area: | |
d374bf14 RK |
241 | if (access_error(fsr, vma)) { |
242 | fault = VM_FAULT_BADACCESS; | |
1da177e4 | 243 | goto out; |
d374bf14 | 244 | } |
1da177e4 | 245 | |
8878a539 | 246 | return handle_mm_fault(mm, vma, addr & PAGE_MASK, flags); |
1da177e4 | 247 | |
1da177e4 | 248 | check_stack: |
9b61a4d1 RK |
249 | /* Don't allow expansion below FIRST_USER_ADDRESS */ |
250 | if (vma->vm_flags & VM_GROWSDOWN && | |
251 | addr >= FIRST_USER_ADDRESS && !expand_stack(vma, addr)) | |
1da177e4 LT |
252 | goto good_area; |
253 | out: | |
254 | return fault; | |
255 | } | |
256 | ||
785d3cd2 | 257 | static int __kprobes |
1da177e4 LT |
258 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
259 | { | |
260 | struct task_struct *tsk; | |
261 | struct mm_struct *mm; | |
2d137c24 | 262 | int fault, sig, code; |
759496ba | 263 | unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; |
1da177e4 | 264 | |
25ce1dd7 NP |
265 | if (notify_page_fault(regs, fsr)) |
266 | return 0; | |
267 | ||
1da177e4 LT |
268 | tsk = current; |
269 | mm = tsk->mm; | |
270 | ||
02fe2845 RK |
271 | /* Enable interrupts if they were enabled in the parent context. */ |
272 | if (interrupts_enabled(regs)) | |
273 | local_irq_enable(); | |
274 | ||
1da177e4 LT |
275 | /* |
276 | * If we're in an interrupt or have no user | |
277 | * context, we must not take the fault.. | |
278 | */ | |
70ffdb93 | 279 | if (faulthandler_disabled() || !mm) |
1da177e4 LT |
280 | goto no_context; |
281 | ||
759496ba JW |
282 | if (user_mode(regs)) |
283 | flags |= FAULT_FLAG_USER; | |
284 | if (fsr & FSR_WRITE) | |
285 | flags |= FAULT_FLAG_WRITE; | |
286 | ||
840ff6a4 RK |
287 | /* |
288 | * As per x86, we may deadlock here. However, since the kernel only | |
289 | * validly references user space from well defined areas of the code, | |
290 | * we can bug out early if this is from code which shouldn't. | |
291 | */ | |
292 | if (!down_read_trylock(&mm->mmap_sem)) { | |
293 | if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc)) | |
294 | goto no_context; | |
8878a539 | 295 | retry: |
840ff6a4 | 296 | down_read(&mm->mmap_sem); |
bf456992 RK |
297 | } else { |
298 | /* | |
299 | * The above down_read_trylock() might have succeeded in | |
300 | * which case, we'll have missed the might_sleep() from | |
301 | * down_read() | |
302 | */ | |
303 | might_sleep(); | |
1d212712 ID |
304 | #ifdef CONFIG_DEBUG_VM |
305 | if (!user_mode(regs) && | |
306 | !search_exception_tables(regs->ARM_pc)) | |
307 | goto no_context; | |
308 | #endif | |
840ff6a4 RK |
309 | } |
310 | ||
8878a539 KC |
311 | fault = __do_page_fault(mm, addr, fsr, flags, tsk); |
312 | ||
313 | /* If we need to retry but a fatal signal is pending, handle the | |
314 | * signal first. We do not need to release the mmap_sem because | |
315 | * it would already be released in __lock_page_or_retry in | |
316 | * mm/filemap.c. */ | |
317 | if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) | |
318 | return 0; | |
319 | ||
320 | /* | |
321 | * Major/minor page fault accounting is only done on the | |
322 | * initial attempt. If we go through a retry, it is extremely | |
323 | * likely that the page will be found in page cache at that point. | |
324 | */ | |
1da177e4 | 325 | |
a8b0ca17 | 326 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); |
dff2aa7a | 327 | if (!(fault & VM_FAULT_ERROR) && flags & FAULT_FLAG_ALLOW_RETRY) { |
8878a539 KC |
328 | if (fault & VM_FAULT_MAJOR) { |
329 | tsk->maj_flt++; | |
330 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, | |
331 | regs, addr); | |
332 | } else { | |
333 | tsk->min_flt++; | |
334 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, | |
335 | regs, addr); | |
336 | } | |
337 | if (fault & VM_FAULT_RETRY) { | |
338 | /* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk | |
339 | * of starvation. */ | |
340 | flags &= ~FAULT_FLAG_ALLOW_RETRY; | |
45cac65b | 341 | flags |= FAULT_FLAG_TRIED; |
8878a539 KC |
342 | goto retry; |
343 | } | |
344 | } | |
345 | ||
346 | up_read(&mm->mmap_sem); | |
7ada189f | 347 | |
1da177e4 | 348 | /* |
0e8fb931 | 349 | * Handle the "normal" case first - VM_FAULT_MAJOR |
1da177e4 | 350 | */ |
5c72fc5c | 351 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS)))) |
1da177e4 LT |
352 | return 0; |
353 | ||
87134102 JW |
354 | /* |
355 | * If we are in kernel mode at this point, we | |
356 | * have no context to handle this fault with. | |
357 | */ | |
358 | if (!user_mode(regs)) | |
359 | goto no_context; | |
360 | ||
b42c6344 RK |
361 | if (fault & VM_FAULT_OOM) { |
362 | /* | |
363 | * We ran out of memory, call the OOM killer, and return to | |
364 | * userspace (which will retry the fault, or kill us if we | |
365 | * got oom-killed) | |
366 | */ | |
367 | pagefault_out_of_memory(); | |
368 | return 0; | |
369 | } | |
370 | ||
83c54070 | 371 | if (fault & VM_FAULT_SIGBUS) { |
2d137c24 | 372 | /* |
373 | * We had some memory, but were unable to | |
374 | * successfully fix up this page fault. | |
375 | */ | |
376 | sig = SIGBUS; | |
377 | code = BUS_ADRERR; | |
83c54070 | 378 | } else { |
2d137c24 | 379 | /* |
380 | * Something tried to access memory that | |
381 | * isn't in our memory map.. | |
382 | */ | |
383 | sig = SIGSEGV; | |
384 | code = fault == VM_FAULT_BADACCESS ? | |
385 | SEGV_ACCERR : SEGV_MAPERR; | |
1da177e4 | 386 | } |
1da177e4 | 387 | |
2d137c24 | 388 | __do_user_fault(tsk, addr, fsr, sig, code, regs); |
389 | return 0; | |
1da177e4 LT |
390 | |
391 | no_context: | |
392 | __do_kernel_fault(mm, addr, fsr, regs); | |
393 | return 0; | |
394 | } | |
09529f7a CM |
395 | #else /* CONFIG_MMU */ |
396 | static int | |
397 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
398 | { | |
399 | return 0; | |
400 | } | |
401 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
402 | |
403 | /* | |
404 | * First Level Translation Fault Handler | |
405 | * | |
406 | * We enter here because the first level page table doesn't contain | |
407 | * a valid entry for the address. | |
408 | * | |
409 | * If the address is in kernel space (>= TASK_SIZE), then we are | |
410 | * probably faulting in the vmalloc() area. | |
411 | * | |
412 | * If the init_task's first level page tables contains the relevant | |
413 | * entry, we copy the it to this task. If not, we send the process | |
414 | * a signal, fixup the exception, or oops the kernel. | |
415 | * | |
416 | * NOTE! We MUST NOT take any locks for this case. We may be in an | |
417 | * interrupt or a critical region, and should only copy the information | |
418 | * from the master page table, nothing more. | |
419 | */ | |
09529f7a | 420 | #ifdef CONFIG_MMU |
785d3cd2 | 421 | static int __kprobes |
1da177e4 LT |
422 | do_translation_fault(unsigned long addr, unsigned int fsr, |
423 | struct pt_regs *regs) | |
424 | { | |
1da177e4 LT |
425 | unsigned int index; |
426 | pgd_t *pgd, *pgd_k; | |
516295e5 | 427 | pud_t *pud, *pud_k; |
1da177e4 LT |
428 | pmd_t *pmd, *pmd_k; |
429 | ||
430 | if (addr < TASK_SIZE) | |
431 | return do_page_fault(addr, fsr, regs); | |
432 | ||
5e27fb78 A |
433 | if (user_mode(regs)) |
434 | goto bad_area; | |
435 | ||
1da177e4 LT |
436 | index = pgd_index(addr); |
437 | ||
1da177e4 LT |
438 | pgd = cpu_get_pgd() + index; |
439 | pgd_k = init_mm.pgd + index; | |
440 | ||
441 | if (pgd_none(*pgd_k)) | |
442 | goto bad_area; | |
1da177e4 LT |
443 | if (!pgd_present(*pgd)) |
444 | set_pgd(pgd, *pgd_k); | |
445 | ||
516295e5 RK |
446 | pud = pud_offset(pgd, addr); |
447 | pud_k = pud_offset(pgd_k, addr); | |
448 | ||
449 | if (pud_none(*pud_k)) | |
450 | goto bad_area; | |
451 | if (!pud_present(*pud)) | |
452 | set_pud(pud, *pud_k); | |
453 | ||
454 | pmd = pmd_offset(pud, addr); | |
455 | pmd_k = pmd_offset(pud_k, addr); | |
1da177e4 | 456 | |
f7b8156d CM |
457 | #ifdef CONFIG_ARM_LPAE |
458 | /* | |
459 | * Only one hardware entry per PMD with LPAE. | |
460 | */ | |
461 | index = 0; | |
462 | #else | |
33a9c41b KS |
463 | /* |
464 | * On ARM one Linux PGD entry contains two hardware entries (see page | |
465 | * tables layout in pgtable.h). We normally guarantee that we always | |
466 | * fill both L1 entries. But create_mapping() doesn't follow the rule. | |
467 | * It can create inidividual L1 entries, so here we have to call | |
468 | * pmd_none() check for the entry really corresponded to address, not | |
469 | * for the first of pair. | |
470 | */ | |
471 | index = (addr >> SECTION_SHIFT) & 1; | |
f7b8156d | 472 | #endif |
33a9c41b | 473 | if (pmd_none(pmd_k[index])) |
1da177e4 LT |
474 | goto bad_area; |
475 | ||
476 | copy_pmd(pmd, pmd_k); | |
477 | return 0; | |
478 | ||
479 | bad_area: | |
e5beac37 | 480 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
481 | return 0; |
482 | } | |
09529f7a CM |
483 | #else /* CONFIG_MMU */ |
484 | static int | |
485 | do_translation_fault(unsigned long addr, unsigned int fsr, | |
486 | struct pt_regs *regs) | |
487 | { | |
488 | return 0; | |
489 | } | |
490 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
491 | |
492 | /* | |
493 | * Some section permission faults need to be handled gracefully. | |
494 | * They can happen due to a __{get,put}_user during an oops. | |
495 | */ | |
809e660f | 496 | #ifndef CONFIG_ARM_LPAE |
1da177e4 LT |
497 | static int |
498 | do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
499 | { | |
e5beac37 | 500 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
501 | return 0; |
502 | } | |
809e660f | 503 | #endif /* CONFIG_ARM_LPAE */ |
1da177e4 LT |
504 | |
505 | /* | |
506 | * This abort handler always returns "fault". | |
507 | */ | |
508 | static int | |
509 | do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
510 | { | |
511 | return 1; | |
512 | } | |
513 | ||
136848d4 | 514 | struct fsr_info { |
1da177e4 LT |
515 | int (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs); |
516 | int sig; | |
cfb0810e | 517 | int code; |
1da177e4 | 518 | const char *name; |
1da177e4 LT |
519 | }; |
520 | ||
136848d4 | 521 | /* FSR definition */ |
f7b8156d CM |
522 | #ifdef CONFIG_ARM_LPAE |
523 | #include "fsr-3level.c" | |
524 | #else | |
136848d4 | 525 | #include "fsr-2level.c" |
f7b8156d | 526 | #endif |
136848d4 | 527 | |
1da177e4 LT |
528 | void __init |
529 | hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
6338a6aa | 530 | int sig, int code, const char *name) |
1da177e4 | 531 | { |
6338a6aa KS |
532 | if (nr < 0 || nr >= ARRAY_SIZE(fsr_info)) |
533 | BUG(); | |
534 | ||
535 | fsr_info[nr].fn = fn; | |
536 | fsr_info[nr].sig = sig; | |
537 | fsr_info[nr].code = code; | |
538 | fsr_info[nr].name = name; | |
1da177e4 LT |
539 | } |
540 | ||
541 | /* | |
542 | * Dispatch a data abort to the relevant handler. | |
543 | */ | |
7ab3f8d5 | 544 | asmlinkage void __exception |
1da177e4 LT |
545 | do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
546 | { | |
c88d6aa7 | 547 | const struct fsr_info *inf = fsr_info + fsr_fs(fsr); |
cfb0810e | 548 | struct siginfo info; |
1da177e4 | 549 | |
df297bf6 | 550 | if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs)) |
1da177e4 LT |
551 | return; |
552 | ||
4ed89f22 | 553 | pr_alert("Unhandled fault: %s (0x%03x) at 0x%08lx\n", |
1da177e4 | 554 | inf->name, fsr, addr); |
6d021b72 | 555 | show_pte(current->mm, addr); |
cfb0810e RK |
556 | |
557 | info.si_signo = inf->sig; | |
558 | info.si_errno = 0; | |
559 | info.si_code = inf->code; | |
560 | info.si_addr = (void __user *)addr; | |
1eeb66a1 | 561 | arm_notify_die("", regs, &info, fsr, 0); |
1da177e4 LT |
562 | } |
563 | ||
3a4b5dca WD |
564 | void __init |
565 | hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
566 | int sig, int code, const char *name) | |
567 | { | |
568 | if (nr < 0 || nr >= ARRAY_SIZE(ifsr_info)) | |
569 | BUG(); | |
570 | ||
571 | ifsr_info[nr].fn = fn; | |
572 | ifsr_info[nr].sig = sig; | |
573 | ifsr_info[nr].code = code; | |
574 | ifsr_info[nr].name = name; | |
575 | } | |
576 | ||
7ab3f8d5 | 577 | asmlinkage void __exception |
4fb28474 | 578 | do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) |
1da177e4 | 579 | { |
d25ef8b8 KS |
580 | const struct fsr_info *inf = ifsr_info + fsr_fs(ifsr); |
581 | struct siginfo info; | |
582 | ||
583 | if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs)) | |
584 | return; | |
585 | ||
4ed89f22 | 586 | pr_alert("Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n", |
d25ef8b8 KS |
587 | inf->name, ifsr, addr); |
588 | ||
589 | info.si_signo = inf->sig; | |
590 | info.si_errno = 0; | |
591 | info.si_code = inf->code; | |
592 | info.si_addr = (void __user *)addr; | |
593 | arm_notify_die("", regs, &info, ifsr, 0); | |
1da177e4 LT |
594 | } |
595 | ||
9254970c LS |
596 | /* |
597 | * Abort handler to be used only during first unmasking of asynchronous aborts | |
598 | * on the boot CPU. This makes sure that the machine will not die if the | |
599 | * firmware/bootloader left an imprecise abort pending for us to trip over. | |
600 | */ | |
601 | static int __init early_abort_handler(unsigned long addr, unsigned int fsr, | |
602 | struct pt_regs *regs) | |
603 | { | |
604 | pr_warn("Hit pending asynchronous external abort (FSR=0x%08x) during " | |
605 | "first unmask, this is most likely caused by a " | |
606 | "firmware/bootloader bug.\n", fsr); | |
607 | ||
608 | return 0; | |
609 | } | |
610 | ||
611 | void __init early_abt_enable(void) | |
612 | { | |
613 | fsr_info[22].fn = early_abort_handler; | |
614 | local_abt_enable(); | |
615 | fsr_info[22].fn = do_bad; | |
616 | } | |
617 | ||
f7b8156d | 618 | #ifndef CONFIG_ARM_LPAE |
993bf4ec KS |
619 | static int __init exceptions_init(void) |
620 | { | |
621 | if (cpu_architecture() >= CPU_ARCH_ARMv6) { | |
622 | hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR, | |
623 | "I-cache maintenance fault"); | |
624 | } | |
625 | ||
b8ab5397 KS |
626 | if (cpu_architecture() >= CPU_ARCH_ARMv7) { |
627 | /* | |
628 | * TODO: Access flag faults introduced in ARMv6K. | |
629 | * Runtime check for 'K' extension is needed | |
630 | */ | |
631 | hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPERR, | |
632 | "section access flag fault"); | |
633 | hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPERR, | |
634 | "section access flag fault"); | |
635 | } | |
636 | ||
993bf4ec KS |
637 | return 0; |
638 | } | |
639 | ||
640 | arch_initcall(exceptions_init); | |
f7b8156d | 641 | #endif |