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