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