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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/arch/arm/mm/fault.c | |
4 | * | |
5 | * Copyright (C) 1995 Linus Torvalds | |
6 | * Modifications for ARM processor (c) 1995-2004 Russell King | |
1da177e4 | 7 | */ |
0ea9365a | 8 | #include <linux/extable.h> |
1da177e4 | 9 | #include <linux/signal.h> |
1da177e4 | 10 | #include <linux/mm.h> |
67306da6 | 11 | #include <linux/hardirq.h> |
1da177e4 | 12 | #include <linux/init.h> |
25ce1dd7 | 13 | #include <linux/kprobes.h> |
33fa9b13 | 14 | #include <linux/uaccess.h> |
252d4c27 | 15 | #include <linux/page-flags.h> |
3f07c014 | 16 | #include <linux/sched/signal.h> |
b17b0153 | 17 | #include <linux/sched/debug.h> |
65cec8e3 | 18 | #include <linux/highmem.h> |
7ada189f | 19 | #include <linux/perf_event.h> |
1da177e4 | 20 | |
9f97da78 DH |
21 | #include <asm/system_misc.h> |
22 | #include <asm/system_info.h> | |
1da177e4 | 23 | #include <asm/tlbflush.h> |
1da177e4 LT |
24 | |
25 | #include "fault.h" | |
26 | ||
09529f7a | 27 | #ifdef CONFIG_MMU |
25ce1dd7 | 28 | |
1da177e4 LT |
29 | /* |
30 | * This is useful to dump out the page tables associated with | |
31 | * 'addr' in mm 'mm'. | |
32 | */ | |
49b38c34 | 33 | void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr) |
1da177e4 LT |
34 | { |
35 | pgd_t *pgd; | |
36 | ||
37 | if (!mm) | |
38 | mm = &init_mm; | |
39 | ||
49b38c34 | 40 | printk("%spgd = %p\n", lvl, mm->pgd); |
1da177e4 | 41 | pgd = pgd_offset(mm, addr); |
49b38c34 | 42 | printk("%s[%08lx] *pgd=%08llx", lvl, addr, (long long)pgd_val(*pgd)); |
1da177e4 LT |
43 | |
44 | do { | |
84e6ffb2 | 45 | p4d_t *p4d; |
516295e5 | 46 | pud_t *pud; |
1da177e4 LT |
47 | pmd_t *pmd; |
48 | pte_t *pte; | |
49 | ||
84e6ffb2 MR |
50 | p4d = p4d_offset(pgd, addr); |
51 | if (p4d_none(*p4d)) | |
1da177e4 LT |
52 | break; |
53 | ||
84e6ffb2 | 54 | if (p4d_bad(*p4d)) { |
4ed89f22 | 55 | pr_cont("(bad)"); |
1da177e4 LT |
56 | break; |
57 | } | |
58 | ||
84e6ffb2 | 59 | pud = pud_offset(p4d, addr); |
516295e5 | 60 | if (PTRS_PER_PUD != 1) |
4ed89f22 | 61 | pr_cont(", *pud=%08llx", (long long)pud_val(*pud)); |
516295e5 RK |
62 | |
63 | if (pud_none(*pud)) | |
64 | break; | |
65 | ||
66 | if (pud_bad(*pud)) { | |
4ed89f22 | 67 | pr_cont("(bad)"); |
516295e5 RK |
68 | break; |
69 | } | |
70 | ||
71 | pmd = pmd_offset(pud, addr); | |
da46c79a | 72 | if (PTRS_PER_PMD != 1) |
4ed89f22 | 73 | pr_cont(", *pmd=%08llx", (long long)pmd_val(*pmd)); |
1da177e4 LT |
74 | |
75 | if (pmd_none(*pmd)) | |
76 | break; | |
77 | ||
78 | if (pmd_bad(*pmd)) { | |
4ed89f22 | 79 | pr_cont("(bad)"); |
1da177e4 LT |
80 | break; |
81 | } | |
82 | ||
1da177e4 | 83 | /* We must not map this if we have highmem enabled */ |
252d4c27 NP |
84 | if (PageHighMem(pfn_to_page(pmd_val(*pmd) >> PAGE_SHIFT))) |
85 | break; | |
86 | ||
1da177e4 | 87 | pte = pte_offset_map(pmd, addr); |
4ed89f22 | 88 | pr_cont(", *pte=%08llx", (long long)pte_val(*pte)); |
f7b8156d | 89 | #ifndef CONFIG_ARM_LPAE |
4ed89f22 | 90 | pr_cont(", *ppte=%08llx", |
29a38193 | 91 | (long long)pte_val(pte[PTE_HWTABLE_PTRS])); |
f7b8156d | 92 | #endif |
1da177e4 | 93 | pte_unmap(pte); |
1da177e4 LT |
94 | } while(0); |
95 | ||
4ed89f22 | 96 | pr_cont("\n"); |
1da177e4 | 97 | } |
09529f7a | 98 | #else /* CONFIG_MMU */ |
49b38c34 | 99 | void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr) |
09529f7a CM |
100 | { } |
101 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
102 | |
103 | /* | |
104 | * Oops. The kernel tried to access some page that wasn't present. | |
105 | */ | |
106 | static void | |
107 | __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, | |
108 | struct pt_regs *regs) | |
109 | { | |
110 | /* | |
111 | * Are we prepared to handle this kernel fault? | |
112 | */ | |
113 | if (fixup_exception(regs)) | |
114 | return; | |
115 | ||
116 | /* | |
117 | * No handler, we'll have to terminate things with extreme prejudice. | |
118 | */ | |
119 | bust_spinlocks(1); | |
bafeb7a0 | 120 | pr_alert("8<--- cut here ---\n"); |
4ed89f22 RK |
121 | pr_alert("Unable to handle kernel %s at virtual address %08lx\n", |
122 | (addr < PAGE_SIZE) ? "NULL pointer dereference" : | |
123 | "paging request", addr); | |
1da177e4 | 124 | |
49b38c34 | 125 | show_pte(KERN_ALERT, mm, addr); |
1da177e4 LT |
126 | die("Oops", regs, fsr); |
127 | bust_spinlocks(0); | |
128 | do_exit(SIGKILL); | |
129 | } | |
130 | ||
131 | /* | |
132 | * Something tried to access memory that isn't in our memory map.. | |
133 | * User mode accesses just cause a SIGSEGV | |
134 | */ | |
135 | static void | |
fd65cc84 EB |
136 | __do_user_fault(unsigned long addr, unsigned int fsr, unsigned int sig, |
137 | int code, struct pt_regs *regs) | |
1da177e4 | 138 | { |
fd65cc84 EB |
139 | struct task_struct *tsk = current; |
140 | ||
f5fe12b1 RK |
141 | if (addr > TASK_SIZE) |
142 | harden_branch_predictor(); | |
143 | ||
1da177e4 | 144 | #ifdef CONFIG_DEBUG_USER |
f5274c2d JM |
145 | if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) || |
146 | ((user_debug & UDBG_BUS) && (sig == SIGBUS))) { | |
bafeb7a0 | 147 | pr_err("8<--- cut here ---\n"); |
49b38c34 | 148 | pr_err("%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n", |
2d137c24 | 149 | tsk->comm, sig, addr, fsr); |
49b38c34 | 150 | show_pte(KERN_ERR, tsk->mm, addr); |
1da177e4 LT |
151 | show_regs(regs); |
152 | } | |
153 | #endif | |
e2b85f70 FF |
154 | #ifndef CONFIG_KUSER_HELPERS |
155 | if ((sig == SIGSEGV) && ((addr & PAGE_MASK) == 0xffff0000)) | |
156 | printk_ratelimited(KERN_DEBUG | |
157 | "%s: CONFIG_KUSER_HELPERS disabled at 0x%08lx\n", | |
158 | tsk->comm, addr); | |
159 | #endif | |
1da177e4 LT |
160 | |
161 | tsk->thread.address = addr; | |
162 | tsk->thread.error_code = fsr; | |
163 | tsk->thread.trap_no = 14; | |
2e1661d2 | 164 | force_sig_fault(sig, code, (void __user *)addr); |
1da177e4 LT |
165 | } |
166 | ||
e5beac37 | 167 | void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
1da177e4 | 168 | { |
e5beac37 RK |
169 | struct task_struct *tsk = current; |
170 | struct mm_struct *mm = tsk->active_mm; | |
171 | ||
1da177e4 LT |
172 | /* |
173 | * If we are in kernel mode at this point, we | |
174 | * have no context to handle this fault with. | |
175 | */ | |
176 | if (user_mode(regs)) | |
fd65cc84 | 177 | __do_user_fault(addr, fsr, SIGSEGV, SEGV_MAPERR, regs); |
1da177e4 LT |
178 | else |
179 | __do_kernel_fault(mm, addr, fsr, regs); | |
180 | } | |
181 | ||
09529f7a | 182 | #ifdef CONFIG_MMU |
5c72fc5c NP |
183 | #define VM_FAULT_BADMAP 0x010000 |
184 | #define VM_FAULT_BADACCESS 0x020000 | |
1da177e4 | 185 | |
d374bf14 RK |
186 | /* |
187 | * Check that the permissions on the VMA allow for the fault which occurred. | |
188 | * If we encountered a write fault, we must have write permission, otherwise | |
189 | * we allow any permission. | |
190 | */ | |
191 | static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma) | |
192 | { | |
6cb4d9a2 | 193 | unsigned int mask = VM_ACCESS_FLAGS; |
d374bf14 | 194 | |
83402036 | 195 | if ((fsr & FSR_WRITE) && !(fsr & FSR_CM)) |
d374bf14 | 196 | mask = VM_WRITE; |
df297bf6 RK |
197 | if (fsr & FSR_LNX_PF) |
198 | mask = VM_EXEC; | |
d374bf14 RK |
199 | |
200 | return vma->vm_flags & mask ? false : true; | |
201 | } | |
202 | ||
50a7ca3c | 203 | static vm_fault_t __kprobes |
1da177e4 | 204 | __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, |
8878a539 | 205 | unsigned int flags, struct task_struct *tsk) |
1da177e4 LT |
206 | { |
207 | struct vm_area_struct *vma; | |
50a7ca3c | 208 | vm_fault_t fault; |
1da177e4 LT |
209 | |
210 | vma = find_vma(mm, addr); | |
211 | fault = VM_FAULT_BADMAP; | |
d374bf14 | 212 | if (unlikely(!vma)) |
1da177e4 | 213 | goto out; |
d374bf14 | 214 | if (unlikely(vma->vm_start > addr)) |
1da177e4 LT |
215 | goto check_stack; |
216 | ||
217 | /* | |
218 | * Ok, we have a good vm_area for this | |
219 | * memory access, so we can handle it. | |
220 | */ | |
221 | good_area: | |
d374bf14 RK |
222 | if (access_error(fsr, vma)) { |
223 | fault = VM_FAULT_BADACCESS; | |
1da177e4 | 224 | goto out; |
d374bf14 | 225 | } |
1da177e4 | 226 | |
dcddffd4 | 227 | return handle_mm_fault(vma, addr & PAGE_MASK, flags); |
1da177e4 | 228 | |
1da177e4 | 229 | check_stack: |
9b61a4d1 RK |
230 | /* Don't allow expansion below FIRST_USER_ADDRESS */ |
231 | if (vma->vm_flags & VM_GROWSDOWN && | |
232 | addr >= FIRST_USER_ADDRESS && !expand_stack(vma, addr)) | |
1da177e4 LT |
233 | goto good_area; |
234 | out: | |
235 | return fault; | |
236 | } | |
237 | ||
785d3cd2 | 238 | static int __kprobes |
1da177e4 LT |
239 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
240 | { | |
241 | struct task_struct *tsk; | |
242 | struct mm_struct *mm; | |
50a7ca3c SJ |
243 | int sig, code; |
244 | vm_fault_t fault; | |
dde16072 | 245 | unsigned int flags = FAULT_FLAG_DEFAULT; |
1da177e4 | 246 | |
b98cca44 | 247 | if (kprobe_page_fault(regs, fsr)) |
25ce1dd7 NP |
248 | return 0; |
249 | ||
1da177e4 LT |
250 | tsk = current; |
251 | mm = tsk->mm; | |
252 | ||
02fe2845 RK |
253 | /* Enable interrupts if they were enabled in the parent context. */ |
254 | if (interrupts_enabled(regs)) | |
255 | local_irq_enable(); | |
256 | ||
1da177e4 LT |
257 | /* |
258 | * If we're in an interrupt or have no user | |
259 | * context, we must not take the fault.. | |
260 | */ | |
70ffdb93 | 261 | if (faulthandler_disabled() || !mm) |
1da177e4 LT |
262 | goto no_context; |
263 | ||
759496ba JW |
264 | if (user_mode(regs)) |
265 | flags |= FAULT_FLAG_USER; | |
83402036 | 266 | if ((fsr & FSR_WRITE) && !(fsr & FSR_CM)) |
759496ba JW |
267 | flags |= FAULT_FLAG_WRITE; |
268 | ||
840ff6a4 RK |
269 | /* |
270 | * As per x86, we may deadlock here. However, since the kernel only | |
271 | * validly references user space from well defined areas of the code, | |
272 | * we can bug out early if this is from code which shouldn't. | |
273 | */ | |
d8ed45c5 | 274 | if (!mmap_read_trylock(mm)) { |
840ff6a4 RK |
275 | if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc)) |
276 | goto no_context; | |
8878a539 | 277 | retry: |
d8ed45c5 | 278 | mmap_read_lock(mm); |
bf456992 RK |
279 | } else { |
280 | /* | |
281 | * The above down_read_trylock() might have succeeded in | |
282 | * which case, we'll have missed the might_sleep() from | |
283 | * down_read() | |
284 | */ | |
285 | might_sleep(); | |
1d212712 ID |
286 | #ifdef CONFIG_DEBUG_VM |
287 | if (!user_mode(regs) && | |
288 | !search_exception_tables(regs->ARM_pc)) | |
289 | goto no_context; | |
290 | #endif | |
840ff6a4 RK |
291 | } |
292 | ||
8878a539 KC |
293 | fault = __do_page_fault(mm, addr, fsr, flags, tsk); |
294 | ||
295 | /* If we need to retry but a fatal signal is pending, handle the | |
c1e8d7c6 | 296 | * signal first. We do not need to release the mmap_lock because |
8878a539 KC |
297 | * it would already be released in __lock_page_or_retry in |
298 | * mm/filemap.c. */ | |
4ef87322 | 299 | if (fault_signal_pending(fault, regs)) { |
746a272e MR |
300 | if (!user_mode(regs)) |
301 | goto no_context; | |
8878a539 | 302 | return 0; |
746a272e | 303 | } |
8878a539 KC |
304 | |
305 | /* | |
306 | * Major/minor page fault accounting is only done on the | |
307 | * initial attempt. If we go through a retry, it is extremely | |
308 | * likely that the page will be found in page cache at that point. | |
309 | */ | |
1da177e4 | 310 | |
a8b0ca17 | 311 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); |
dff2aa7a | 312 | if (!(fault & VM_FAULT_ERROR) && flags & FAULT_FLAG_ALLOW_RETRY) { |
8878a539 KC |
313 | if (fault & VM_FAULT_MAJOR) { |
314 | tsk->maj_flt++; | |
315 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, | |
316 | regs, addr); | |
317 | } else { | |
318 | tsk->min_flt++; | |
319 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, | |
320 | regs, addr); | |
321 | } | |
322 | if (fault & VM_FAULT_RETRY) { | |
45cac65b | 323 | flags |= FAULT_FLAG_TRIED; |
8878a539 KC |
324 | goto retry; |
325 | } | |
326 | } | |
327 | ||
d8ed45c5 | 328 | mmap_read_unlock(mm); |
7ada189f | 329 | |
1da177e4 | 330 | /* |
0e8fb931 | 331 | * Handle the "normal" case first - VM_FAULT_MAJOR |
1da177e4 | 332 | */ |
5c72fc5c | 333 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS)))) |
1da177e4 LT |
334 | return 0; |
335 | ||
87134102 JW |
336 | /* |
337 | * If we are in kernel mode at this point, we | |
338 | * have no context to handle this fault with. | |
339 | */ | |
340 | if (!user_mode(regs)) | |
341 | goto no_context; | |
342 | ||
b42c6344 RK |
343 | if (fault & VM_FAULT_OOM) { |
344 | /* | |
345 | * We ran out of memory, call the OOM killer, and return to | |
346 | * userspace (which will retry the fault, or kill us if we | |
347 | * got oom-killed) | |
348 | */ | |
349 | pagefault_out_of_memory(); | |
350 | return 0; | |
351 | } | |
352 | ||
83c54070 | 353 | if (fault & VM_FAULT_SIGBUS) { |
2d137c24 | 354 | /* |
355 | * We had some memory, but were unable to | |
356 | * successfully fix up this page fault. | |
357 | */ | |
358 | sig = SIGBUS; | |
359 | code = BUS_ADRERR; | |
83c54070 | 360 | } else { |
2d137c24 | 361 | /* |
362 | * Something tried to access memory that | |
363 | * isn't in our memory map.. | |
364 | */ | |
365 | sig = SIGSEGV; | |
366 | code = fault == VM_FAULT_BADACCESS ? | |
367 | SEGV_ACCERR : SEGV_MAPERR; | |
1da177e4 | 368 | } |
1da177e4 | 369 | |
fd65cc84 | 370 | __do_user_fault(addr, fsr, sig, code, regs); |
2d137c24 | 371 | return 0; |
1da177e4 LT |
372 | |
373 | no_context: | |
374 | __do_kernel_fault(mm, addr, fsr, regs); | |
375 | return 0; | |
376 | } | |
09529f7a CM |
377 | #else /* CONFIG_MMU */ |
378 | static int | |
379 | do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
380 | { | |
381 | return 0; | |
382 | } | |
383 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
384 | |
385 | /* | |
386 | * First Level Translation Fault Handler | |
387 | * | |
388 | * We enter here because the first level page table doesn't contain | |
389 | * a valid entry for the address. | |
390 | * | |
391 | * If the address is in kernel space (>= TASK_SIZE), then we are | |
392 | * probably faulting in the vmalloc() area. | |
393 | * | |
394 | * If the init_task's first level page tables contains the relevant | |
395 | * entry, we copy the it to this task. If not, we send the process | |
396 | * a signal, fixup the exception, or oops the kernel. | |
397 | * | |
398 | * NOTE! We MUST NOT take any locks for this case. We may be in an | |
399 | * interrupt or a critical region, and should only copy the information | |
400 | * from the master page table, nothing more. | |
401 | */ | |
09529f7a | 402 | #ifdef CONFIG_MMU |
785d3cd2 | 403 | static int __kprobes |
1da177e4 LT |
404 | do_translation_fault(unsigned long addr, unsigned int fsr, |
405 | struct pt_regs *regs) | |
406 | { | |
1da177e4 LT |
407 | unsigned int index; |
408 | pgd_t *pgd, *pgd_k; | |
84e6ffb2 | 409 | p4d_t *p4d, *p4d_k; |
516295e5 | 410 | pud_t *pud, *pud_k; |
1da177e4 LT |
411 | pmd_t *pmd, *pmd_k; |
412 | ||
413 | if (addr < TASK_SIZE) | |
414 | return do_page_fault(addr, fsr, regs); | |
415 | ||
5e27fb78 A |
416 | if (user_mode(regs)) |
417 | goto bad_area; | |
418 | ||
1da177e4 LT |
419 | index = pgd_index(addr); |
420 | ||
1da177e4 LT |
421 | pgd = cpu_get_pgd() + index; |
422 | pgd_k = init_mm.pgd + index; | |
423 | ||
84e6ffb2 MR |
424 | p4d = p4d_offset(pgd, addr); |
425 | p4d_k = p4d_offset(pgd_k, addr); | |
426 | ||
427 | if (p4d_none(*p4d_k)) | |
1da177e4 | 428 | goto bad_area; |
84e6ffb2 MR |
429 | if (!p4d_present(*p4d)) |
430 | set_p4d(p4d, *p4d_k); | |
1da177e4 | 431 | |
84e6ffb2 MR |
432 | pud = pud_offset(p4d, addr); |
433 | pud_k = pud_offset(p4d_k, addr); | |
516295e5 RK |
434 | |
435 | if (pud_none(*pud_k)) | |
436 | goto bad_area; | |
437 | if (!pud_present(*pud)) | |
438 | set_pud(pud, *pud_k); | |
439 | ||
440 | pmd = pmd_offset(pud, addr); | |
441 | pmd_k = pmd_offset(pud_k, addr); | |
1da177e4 | 442 | |
f7b8156d CM |
443 | #ifdef CONFIG_ARM_LPAE |
444 | /* | |
445 | * Only one hardware entry per PMD with LPAE. | |
446 | */ | |
447 | index = 0; | |
448 | #else | |
33a9c41b KS |
449 | /* |
450 | * On ARM one Linux PGD entry contains two hardware entries (see page | |
451 | * tables layout in pgtable.h). We normally guarantee that we always | |
452 | * fill both L1 entries. But create_mapping() doesn't follow the rule. | |
453 | * It can create inidividual L1 entries, so here we have to call | |
454 | * pmd_none() check for the entry really corresponded to address, not | |
455 | * for the first of pair. | |
456 | */ | |
457 | index = (addr >> SECTION_SHIFT) & 1; | |
f7b8156d | 458 | #endif |
33a9c41b | 459 | if (pmd_none(pmd_k[index])) |
1da177e4 LT |
460 | goto bad_area; |
461 | ||
462 | copy_pmd(pmd, pmd_k); | |
463 | return 0; | |
464 | ||
465 | bad_area: | |
e5beac37 | 466 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
467 | return 0; |
468 | } | |
09529f7a CM |
469 | #else /* CONFIG_MMU */ |
470 | static int | |
471 | do_translation_fault(unsigned long addr, unsigned int fsr, | |
472 | struct pt_regs *regs) | |
473 | { | |
474 | return 0; | |
475 | } | |
476 | #endif /* CONFIG_MMU */ | |
1da177e4 LT |
477 | |
478 | /* | |
479 | * Some section permission faults need to be handled gracefully. | |
480 | * They can happen due to a __{get,put}_user during an oops. | |
481 | */ | |
809e660f | 482 | #ifndef CONFIG_ARM_LPAE |
1da177e4 LT |
483 | static int |
484 | do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
485 | { | |
e5beac37 | 486 | do_bad_area(addr, fsr, regs); |
1da177e4 LT |
487 | return 0; |
488 | } | |
809e660f | 489 | #endif /* CONFIG_ARM_LPAE */ |
1da177e4 LT |
490 | |
491 | /* | |
492 | * This abort handler always returns "fault". | |
493 | */ | |
494 | static int | |
495 | do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs) | |
496 | { | |
497 | return 1; | |
498 | } | |
499 | ||
136848d4 | 500 | struct fsr_info { |
1da177e4 LT |
501 | int (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs); |
502 | int sig; | |
cfb0810e | 503 | int code; |
1da177e4 | 504 | const char *name; |
1da177e4 LT |
505 | }; |
506 | ||
136848d4 | 507 | /* FSR definition */ |
f7b8156d CM |
508 | #ifdef CONFIG_ARM_LPAE |
509 | #include "fsr-3level.c" | |
510 | #else | |
136848d4 | 511 | #include "fsr-2level.c" |
f7b8156d | 512 | #endif |
136848d4 | 513 | |
1da177e4 LT |
514 | void __init |
515 | hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
6338a6aa | 516 | int sig, int code, const char *name) |
1da177e4 | 517 | { |
6338a6aa KS |
518 | if (nr < 0 || nr >= ARRAY_SIZE(fsr_info)) |
519 | BUG(); | |
520 | ||
521 | fsr_info[nr].fn = fn; | |
522 | fsr_info[nr].sig = sig; | |
523 | fsr_info[nr].code = code; | |
524 | fsr_info[nr].name = name; | |
1da177e4 LT |
525 | } |
526 | ||
527 | /* | |
528 | * Dispatch a data abort to the relevant handler. | |
529 | */ | |
c6089061 | 530 | asmlinkage void |
1da177e4 LT |
531 | do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs) |
532 | { | |
c88d6aa7 | 533 | const struct fsr_info *inf = fsr_info + fsr_fs(fsr); |
1da177e4 | 534 | |
df297bf6 | 535 | if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs)) |
1da177e4 LT |
536 | return; |
537 | ||
bafeb7a0 | 538 | pr_alert("8<--- cut here ---\n"); |
4ed89f22 | 539 | pr_alert("Unhandled fault: %s (0x%03x) at 0x%08lx\n", |
1da177e4 | 540 | inf->name, fsr, addr); |
49b38c34 | 541 | show_pte(KERN_ALERT, current->mm, addr); |
cfb0810e | 542 | |
05e792e3 EB |
543 | arm_notify_die("", regs, inf->sig, inf->code, (void __user *)addr, |
544 | fsr, 0); | |
1da177e4 LT |
545 | } |
546 | ||
3a4b5dca WD |
547 | void __init |
548 | hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), | |
549 | int sig, int code, const char *name) | |
550 | { | |
551 | if (nr < 0 || nr >= ARRAY_SIZE(ifsr_info)) | |
552 | BUG(); | |
553 | ||
554 | ifsr_info[nr].fn = fn; | |
555 | ifsr_info[nr].sig = sig; | |
556 | ifsr_info[nr].code = code; | |
557 | ifsr_info[nr].name = name; | |
558 | } | |
559 | ||
c6089061 | 560 | asmlinkage void |
4fb28474 | 561 | do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) |
1da177e4 | 562 | { |
d25ef8b8 | 563 | const struct fsr_info *inf = ifsr_info + fsr_fs(ifsr); |
d25ef8b8 KS |
564 | |
565 | if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs)) | |
566 | return; | |
567 | ||
4ed89f22 | 568 | pr_alert("Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n", |
d25ef8b8 KS |
569 | inf->name, ifsr, addr); |
570 | ||
05e792e3 EB |
571 | arm_notify_die("", regs, inf->sig, inf->code, (void __user *)addr, |
572 | ifsr, 0); | |
1da177e4 LT |
573 | } |
574 | ||
9254970c LS |
575 | /* |
576 | * Abort handler to be used only during first unmasking of asynchronous aborts | |
577 | * on the boot CPU. This makes sure that the machine will not die if the | |
578 | * firmware/bootloader left an imprecise abort pending for us to trip over. | |
579 | */ | |
580 | static int __init early_abort_handler(unsigned long addr, unsigned int fsr, | |
581 | struct pt_regs *regs) | |
582 | { | |
583 | pr_warn("Hit pending asynchronous external abort (FSR=0x%08x) during " | |
584 | "first unmask, this is most likely caused by a " | |
585 | "firmware/bootloader bug.\n", fsr); | |
586 | ||
587 | return 0; | |
588 | } | |
589 | ||
590 | void __init early_abt_enable(void) | |
591 | { | |
97a98ae5 | 592 | fsr_info[FSR_FS_AEA].fn = early_abort_handler; |
9254970c | 593 | local_abt_enable(); |
97a98ae5 | 594 | fsr_info[FSR_FS_AEA].fn = do_bad; |
9254970c LS |
595 | } |
596 | ||
f7b8156d | 597 | #ifndef CONFIG_ARM_LPAE |
993bf4ec KS |
598 | static int __init exceptions_init(void) |
599 | { | |
600 | if (cpu_architecture() >= CPU_ARCH_ARMv6) { | |
601 | hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR, | |
602 | "I-cache maintenance fault"); | |
603 | } | |
604 | ||
b8ab5397 KS |
605 | if (cpu_architecture() >= CPU_ARCH_ARMv7) { |
606 | /* | |
607 | * TODO: Access flag faults introduced in ARMv6K. | |
608 | * Runtime check for 'K' extension is needed | |
609 | */ | |
610 | hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPERR, | |
611 | "section access flag fault"); | |
612 | hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPERR, | |
613 | "section access flag fault"); | |
614 | } | |
615 | ||
993bf4ec KS |
616 | return 0; |
617 | } | |
618 | ||
619 | arch_initcall(exceptions_init); | |
f7b8156d | 620 | #endif |