Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Based on arch/arm/mm/fault.c |
| 3 | * |
| 4 | * Copyright (C) 1995 Linus Torvalds |
| 5 | * Copyright (C) 1995-2004 Russell King |
| 6 | * Copyright (C) 2012 ARM Ltd. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 19 | */ |
| 20 | |
| 21 | #include <linux/module.h> |
| 22 | #include <linux/signal.h> |
| 23 | #include <linux/mm.h> |
| 24 | #include <linux/hardirq.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/kprobes.h> |
| 27 | #include <linux/uaccess.h> |
| 28 | #include <linux/page-flags.h> |
| 29 | #include <linux/sched.h> |
| 30 | #include <linux/highmem.h> |
| 31 | #include <linux/perf_event.h> |
| 32 | |
| 33 | #include <asm/exception.h> |
| 34 | #include <asm/debug-monitors.h> |
| 35 | #include <asm/system_misc.h> |
| 36 | #include <asm/pgtable.h> |
| 37 | #include <asm/tlbflush.h> |
| 38 | |
Catalin Marinas | 3495386b | 2012-10-24 16:34:02 +0100 | [diff] [blame] | 39 | static const char *fault_name(unsigned int esr); |
| 40 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 41 | /* |
| 42 | * Dump out the page tables associated with 'addr' in mm 'mm'. |
| 43 | */ |
| 44 | void show_pte(struct mm_struct *mm, unsigned long addr) |
| 45 | { |
| 46 | pgd_t *pgd; |
| 47 | |
| 48 | if (!mm) |
| 49 | mm = &init_mm; |
| 50 | |
| 51 | pr_alert("pgd = %p\n", mm->pgd); |
| 52 | pgd = pgd_offset(mm, addr); |
| 53 | pr_alert("[%08lx] *pgd=%016llx", addr, pgd_val(*pgd)); |
| 54 | |
| 55 | do { |
| 56 | pud_t *pud; |
| 57 | pmd_t *pmd; |
| 58 | pte_t *pte; |
| 59 | |
Steve Capper | 4339e3f3 | 2013-04-19 15:49:31 +0100 | [diff] [blame] | 60 | if (pgd_none(*pgd) || pgd_bad(*pgd)) |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 61 | break; |
| 62 | |
| 63 | pud = pud_offset(pgd, addr); |
Steve Capper | 4339e3f3 | 2013-04-19 15:49:31 +0100 | [diff] [blame] | 64 | if (pud_none(*pud) || pud_bad(*pud)) |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 65 | break; |
| 66 | |
| 67 | pmd = pmd_offset(pud, addr); |
| 68 | printk(", *pmd=%016llx", pmd_val(*pmd)); |
Steve Capper | 4339e3f3 | 2013-04-19 15:49:31 +0100 | [diff] [blame] | 69 | if (pmd_none(*pmd) || pmd_bad(*pmd)) |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 70 | break; |
| 71 | |
| 72 | pte = pte_offset_map(pmd, addr); |
| 73 | printk(", *pte=%016llx", pte_val(*pte)); |
| 74 | pte_unmap(pte); |
| 75 | } while(0); |
| 76 | |
| 77 | printk("\n"); |
| 78 | } |
| 79 | |
| 80 | /* |
| 81 | * The kernel tried to access some page that wasn't present. |
| 82 | */ |
| 83 | static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr, |
| 84 | unsigned int esr, struct pt_regs *regs) |
| 85 | { |
| 86 | /* |
| 87 | * Are we prepared to handle this kernel fault? |
| 88 | */ |
| 89 | if (fixup_exception(regs)) |
| 90 | return; |
| 91 | |
| 92 | /* |
| 93 | * No handler, we'll have to terminate things with extreme prejudice. |
| 94 | */ |
| 95 | bust_spinlocks(1); |
| 96 | pr_alert("Unable to handle kernel %s at virtual address %08lx\n", |
| 97 | (addr < PAGE_SIZE) ? "NULL pointer dereference" : |
| 98 | "paging request", addr); |
| 99 | |
| 100 | show_pte(mm, addr); |
| 101 | die("Oops", regs, esr); |
| 102 | bust_spinlocks(0); |
| 103 | do_exit(SIGKILL); |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | * Something tried to access memory that isn't in our memory map. User mode |
| 108 | * accesses just cause a SIGSEGV |
| 109 | */ |
| 110 | static void __do_user_fault(struct task_struct *tsk, unsigned long addr, |
| 111 | unsigned int esr, unsigned int sig, int code, |
| 112 | struct pt_regs *regs) |
| 113 | { |
| 114 | struct siginfo si; |
| 115 | |
Catalin Marinas | 953dbbe | 2013-05-21 12:16:56 +0100 | [diff] [blame] | 116 | if (show_unhandled_signals && unhandled_signal(tsk, sig) && |
| 117 | printk_ratelimit()) { |
Catalin Marinas | 3495386b | 2012-10-24 16:34:02 +0100 | [diff] [blame] | 118 | pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n", |
| 119 | tsk->comm, task_pid_nr(tsk), fault_name(esr), sig, |
| 120 | addr, esr); |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 121 | show_pte(tsk->mm, addr); |
| 122 | show_regs(regs); |
| 123 | } |
| 124 | |
| 125 | tsk->thread.fault_address = addr; |
| 126 | si.si_signo = sig; |
| 127 | si.si_errno = 0; |
| 128 | si.si_code = code; |
| 129 | si.si_addr = (void __user *)addr; |
| 130 | force_sig_info(sig, &si, tsk); |
| 131 | } |
| 132 | |
Catalin Marinas | 59f67e1 | 2013-09-16 15:18:28 +0100 | [diff] [blame] | 133 | static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs) |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 134 | { |
| 135 | struct task_struct *tsk = current; |
| 136 | struct mm_struct *mm = tsk->active_mm; |
| 137 | |
| 138 | /* |
| 139 | * If we are in kernel mode at this point, we have no context to |
| 140 | * handle this fault with. |
| 141 | */ |
| 142 | if (user_mode(regs)) |
| 143 | __do_user_fault(tsk, addr, esr, SIGSEGV, SEGV_MAPERR, regs); |
| 144 | else |
| 145 | __do_kernel_fault(mm, addr, esr, regs); |
| 146 | } |
| 147 | |
| 148 | #define VM_FAULT_BADMAP 0x010000 |
| 149 | #define VM_FAULT_BADACCESS 0x020000 |
| 150 | |
| 151 | #define ESR_WRITE (1 << 6) |
Catalin Marinas | 0e7f7bc | 2013-05-07 16:57:06 +0100 | [diff] [blame] | 152 | #define ESR_CM (1 << 8) |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 153 | #define ESR_LNX_EXEC (1 << 24) |
| 154 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 155 | static int __do_page_fault(struct mm_struct *mm, unsigned long addr, |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 156 | unsigned int mm_flags, unsigned long vm_flags, |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 157 | struct task_struct *tsk) |
| 158 | { |
| 159 | struct vm_area_struct *vma; |
| 160 | int fault; |
| 161 | |
| 162 | vma = find_vma(mm, addr); |
| 163 | fault = VM_FAULT_BADMAP; |
| 164 | if (unlikely(!vma)) |
| 165 | goto out; |
| 166 | if (unlikely(vma->vm_start > addr)) |
| 167 | goto check_stack; |
| 168 | |
| 169 | /* |
| 170 | * Ok, we have a good vm_area for this memory access, so we can handle |
| 171 | * it. |
| 172 | */ |
| 173 | good_area: |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 174 | /* |
| 175 | * Check that the permissions on the VMA allow for the fault which |
| 176 | * occurred. If we encountered a write or exec fault, we must have |
| 177 | * appropriate permissions, otherwise we allow any permission. |
| 178 | */ |
| 179 | if (!(vma->vm_flags & vm_flags)) { |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 180 | fault = VM_FAULT_BADACCESS; |
| 181 | goto out; |
| 182 | } |
| 183 | |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 184 | return handle_mm_fault(mm, vma, addr & PAGE_MASK, mm_flags); |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 185 | |
| 186 | check_stack: |
| 187 | if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr)) |
| 188 | goto good_area; |
| 189 | out: |
| 190 | return fault; |
| 191 | } |
| 192 | |
| 193 | static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, |
| 194 | struct pt_regs *regs) |
| 195 | { |
| 196 | struct task_struct *tsk; |
| 197 | struct mm_struct *mm; |
| 198 | int fault, sig, code; |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 199 | unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC; |
| 200 | unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; |
| 201 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 202 | tsk = current; |
| 203 | mm = tsk->mm; |
| 204 | |
| 205 | /* Enable interrupts if they were enabled in the parent context. */ |
| 206 | if (interrupts_enabled(regs)) |
| 207 | local_irq_enable(); |
| 208 | |
| 209 | /* |
| 210 | * If we're in an interrupt or have no user context, we must not take |
| 211 | * the fault. |
| 212 | */ |
| 213 | if (in_atomic() || !mm) |
| 214 | goto no_context; |
| 215 | |
Johannes Weiner | 759496b | 2013-09-12 15:13:39 -0700 | [diff] [blame] | 216 | if (user_mode(regs)) |
| 217 | mm_flags |= FAULT_FLAG_USER; |
| 218 | |
| 219 | if (esr & ESR_LNX_EXEC) { |
| 220 | vm_flags = VM_EXEC; |
| 221 | } else if ((esr & ESR_WRITE) && !(esr & ESR_CM)) { |
| 222 | vm_flags = VM_WRITE; |
| 223 | mm_flags |= FAULT_FLAG_WRITE; |
| 224 | } |
| 225 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 226 | /* |
| 227 | * As per x86, we may deadlock here. However, since the kernel only |
| 228 | * validly references user space from well defined areas of the code, |
| 229 | * we can bug out early if this is from code which shouldn't. |
| 230 | */ |
| 231 | if (!down_read_trylock(&mm->mmap_sem)) { |
| 232 | if (!user_mode(regs) && !search_exception_tables(regs->pc)) |
| 233 | goto no_context; |
| 234 | retry: |
| 235 | down_read(&mm->mmap_sem); |
| 236 | } else { |
| 237 | /* |
| 238 | * The above down_read_trylock() might have succeeded in which |
| 239 | * case, we'll have missed the might_sleep() from down_read(). |
| 240 | */ |
| 241 | might_sleep(); |
| 242 | #ifdef CONFIG_DEBUG_VM |
| 243 | if (!user_mode(regs) && !search_exception_tables(regs->pc)) |
| 244 | goto no_context; |
| 245 | #endif |
| 246 | } |
| 247 | |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 248 | fault = __do_page_fault(mm, addr, mm_flags, vm_flags, tsk); |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 249 | |
| 250 | /* |
| 251 | * If we need to retry but a fatal signal is pending, handle the |
| 252 | * signal first. We do not need to release the mmap_sem because it |
| 253 | * would already be released in __lock_page_or_retry in mm/filemap.c. |
| 254 | */ |
| 255 | if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) |
| 256 | return 0; |
| 257 | |
| 258 | /* |
| 259 | * Major/minor page fault accounting is only done on the initial |
| 260 | * attempt. If we go through a retry, it is extremely likely that the |
| 261 | * page will be found in page cache at that point. |
| 262 | */ |
| 263 | |
| 264 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 265 | if (mm_flags & FAULT_FLAG_ALLOW_RETRY) { |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 266 | if (fault & VM_FAULT_MAJOR) { |
| 267 | tsk->maj_flt++; |
| 268 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, |
| 269 | addr); |
| 270 | } else { |
| 271 | tsk->min_flt++; |
| 272 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, |
| 273 | addr); |
| 274 | } |
| 275 | if (fault & VM_FAULT_RETRY) { |
| 276 | /* |
| 277 | * Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk of |
| 278 | * starvation. |
| 279 | */ |
Will Deacon | db6f410 | 2013-07-19 15:37:12 +0100 | [diff] [blame] | 280 | mm_flags &= ~FAULT_FLAG_ALLOW_RETRY; |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 281 | goto retry; |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | up_read(&mm->mmap_sem); |
| 286 | |
| 287 | /* |
| 288 | * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR |
| 289 | */ |
| 290 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | |
| 291 | VM_FAULT_BADACCESS)))) |
| 292 | return 0; |
| 293 | |
Johannes Weiner | 8713410 | 2013-09-12 15:13:38 -0700 | [diff] [blame] | 294 | /* |
| 295 | * If we are in kernel mode at this point, we have no context to |
| 296 | * handle this fault with. |
| 297 | */ |
| 298 | if (!user_mode(regs)) |
| 299 | goto no_context; |
| 300 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 301 | if (fault & VM_FAULT_OOM) { |
| 302 | /* |
| 303 | * We ran out of memory, call the OOM killer, and return to |
| 304 | * userspace (which will retry the fault, or kill us if we got |
| 305 | * oom-killed). |
| 306 | */ |
| 307 | pagefault_out_of_memory(); |
| 308 | return 0; |
| 309 | } |
| 310 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 311 | if (fault & VM_FAULT_SIGBUS) { |
| 312 | /* |
| 313 | * We had some memory, but were unable to successfully fix up |
| 314 | * this page fault. |
| 315 | */ |
| 316 | sig = SIGBUS; |
| 317 | code = BUS_ADRERR; |
| 318 | } else { |
| 319 | /* |
| 320 | * Something tried to access memory that isn't in our memory |
| 321 | * map. |
| 322 | */ |
| 323 | sig = SIGSEGV; |
| 324 | code = fault == VM_FAULT_BADACCESS ? |
| 325 | SEGV_ACCERR : SEGV_MAPERR; |
| 326 | } |
| 327 | |
| 328 | __do_user_fault(tsk, addr, esr, sig, code, regs); |
| 329 | return 0; |
| 330 | |
| 331 | no_context: |
| 332 | __do_kernel_fault(mm, addr, esr, regs); |
| 333 | return 0; |
| 334 | } |
| 335 | |
| 336 | /* |
| 337 | * First Level Translation Fault Handler |
| 338 | * |
| 339 | * We enter here because the first level page table doesn't contain a valid |
| 340 | * entry for the address. |
| 341 | * |
| 342 | * If the address is in kernel space (>= TASK_SIZE), then we are probably |
| 343 | * faulting in the vmalloc() area. |
| 344 | * |
| 345 | * If the init_task's first level page tables contains the relevant entry, we |
| 346 | * copy the it to this task. If not, we send the process a signal, fixup the |
| 347 | * exception, or oops the kernel. |
| 348 | * |
| 349 | * NOTE! We MUST NOT take any locks for this case. We may be in an interrupt |
| 350 | * or a critical region, and should only copy the information from the master |
| 351 | * page table, nothing more. |
| 352 | */ |
| 353 | static int __kprobes do_translation_fault(unsigned long addr, |
| 354 | unsigned int esr, |
| 355 | struct pt_regs *regs) |
| 356 | { |
| 357 | if (addr < TASK_SIZE) |
| 358 | return do_page_fault(addr, esr, regs); |
| 359 | |
| 360 | do_bad_area(addr, esr, regs); |
| 361 | return 0; |
| 362 | } |
| 363 | |
| 364 | /* |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 365 | * This abort handler always returns "fault". |
| 366 | */ |
| 367 | static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs) |
| 368 | { |
| 369 | return 1; |
| 370 | } |
| 371 | |
| 372 | static struct fault_info { |
| 373 | int (*fn)(unsigned long addr, unsigned int esr, struct pt_regs *regs); |
| 374 | int sig; |
| 375 | int code; |
| 376 | const char *name; |
| 377 | } fault_info[] = { |
| 378 | { do_bad, SIGBUS, 0, "ttbr address size fault" }, |
| 379 | { do_bad, SIGBUS, 0, "level 1 address size fault" }, |
| 380 | { do_bad, SIGBUS, 0, "level 2 address size fault" }, |
| 381 | { do_bad, SIGBUS, 0, "level 3 address size fault" }, |
| 382 | { do_translation_fault, SIGSEGV, SEGV_MAPERR, "input address range fault" }, |
| 383 | { do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 1 translation fault" }, |
| 384 | { do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 2 translation fault" }, |
| 385 | { do_page_fault, SIGSEGV, SEGV_MAPERR, "level 3 translation fault" }, |
| 386 | { do_bad, SIGBUS, 0, "reserved access flag fault" }, |
Steve Capper | 084bd29 | 2013-04-10 13:48:00 +0100 | [diff] [blame] | 387 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 access flag fault" }, |
| 388 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 access flag fault" }, |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 389 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 access flag fault" }, |
| 390 | { do_bad, SIGBUS, 0, "reserved permission fault" }, |
Steve Capper | 084bd29 | 2013-04-10 13:48:00 +0100 | [diff] [blame] | 391 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 permission fault" }, |
| 392 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 permission fault" }, |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 393 | { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 permission fault" }, |
| 394 | { do_bad, SIGBUS, 0, "synchronous external abort" }, |
| 395 | { do_bad, SIGBUS, 0, "asynchronous external abort" }, |
| 396 | { do_bad, SIGBUS, 0, "unknown 18" }, |
| 397 | { do_bad, SIGBUS, 0, "unknown 19" }, |
| 398 | { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, |
| 399 | { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, |
| 400 | { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, |
| 401 | { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, |
| 402 | { do_bad, SIGBUS, 0, "synchronous parity error" }, |
| 403 | { do_bad, SIGBUS, 0, "asynchronous parity error" }, |
| 404 | { do_bad, SIGBUS, 0, "unknown 26" }, |
| 405 | { do_bad, SIGBUS, 0, "unknown 27" }, |
| 406 | { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, |
| 407 | { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, |
| 408 | { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, |
| 409 | { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, |
| 410 | { do_bad, SIGBUS, 0, "unknown 32" }, |
| 411 | { do_bad, SIGBUS, BUS_ADRALN, "alignment fault" }, |
| 412 | { do_bad, SIGBUS, 0, "debug event" }, |
| 413 | { do_bad, SIGBUS, 0, "unknown 35" }, |
| 414 | { do_bad, SIGBUS, 0, "unknown 36" }, |
| 415 | { do_bad, SIGBUS, 0, "unknown 37" }, |
| 416 | { do_bad, SIGBUS, 0, "unknown 38" }, |
| 417 | { do_bad, SIGBUS, 0, "unknown 39" }, |
| 418 | { do_bad, SIGBUS, 0, "unknown 40" }, |
| 419 | { do_bad, SIGBUS, 0, "unknown 41" }, |
| 420 | { do_bad, SIGBUS, 0, "unknown 42" }, |
| 421 | { do_bad, SIGBUS, 0, "unknown 43" }, |
| 422 | { do_bad, SIGBUS, 0, "unknown 44" }, |
| 423 | { do_bad, SIGBUS, 0, "unknown 45" }, |
| 424 | { do_bad, SIGBUS, 0, "unknown 46" }, |
| 425 | { do_bad, SIGBUS, 0, "unknown 47" }, |
| 426 | { do_bad, SIGBUS, 0, "unknown 48" }, |
| 427 | { do_bad, SIGBUS, 0, "unknown 49" }, |
| 428 | { do_bad, SIGBUS, 0, "unknown 50" }, |
| 429 | { do_bad, SIGBUS, 0, "unknown 51" }, |
| 430 | { do_bad, SIGBUS, 0, "implementation fault (lockdown abort)" }, |
| 431 | { do_bad, SIGBUS, 0, "unknown 53" }, |
| 432 | { do_bad, SIGBUS, 0, "unknown 54" }, |
| 433 | { do_bad, SIGBUS, 0, "unknown 55" }, |
| 434 | { do_bad, SIGBUS, 0, "unknown 56" }, |
| 435 | { do_bad, SIGBUS, 0, "unknown 57" }, |
| 436 | { do_bad, SIGBUS, 0, "implementation fault (coprocessor abort)" }, |
| 437 | { do_bad, SIGBUS, 0, "unknown 59" }, |
| 438 | { do_bad, SIGBUS, 0, "unknown 60" }, |
| 439 | { do_bad, SIGBUS, 0, "unknown 61" }, |
| 440 | { do_bad, SIGBUS, 0, "unknown 62" }, |
| 441 | { do_bad, SIGBUS, 0, "unknown 63" }, |
| 442 | }; |
| 443 | |
Catalin Marinas | 3495386b | 2012-10-24 16:34:02 +0100 | [diff] [blame] | 444 | static const char *fault_name(unsigned int esr) |
| 445 | { |
| 446 | const struct fault_info *inf = fault_info + (esr & 63); |
| 447 | return inf->name; |
| 448 | } |
| 449 | |
Catalin Marinas | 1d18c47 | 2012-03-05 11:49:27 +0000 | [diff] [blame] | 450 | /* |
| 451 | * Dispatch a data abort to the relevant handler. |
| 452 | */ |
| 453 | asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr, |
| 454 | struct pt_regs *regs) |
| 455 | { |
| 456 | const struct fault_info *inf = fault_info + (esr & 63); |
| 457 | struct siginfo info; |
| 458 | |
| 459 | if (!inf->fn(addr, esr, regs)) |
| 460 | return; |
| 461 | |
| 462 | pr_alert("Unhandled fault: %s (0x%08x) at 0x%016lx\n", |
| 463 | inf->name, esr, addr); |
| 464 | |
| 465 | info.si_signo = inf->sig; |
| 466 | info.si_errno = 0; |
| 467 | info.si_code = inf->code; |
| 468 | info.si_addr = (void __user *)addr; |
| 469 | arm64_notify_die("", regs, &info, esr); |
| 470 | } |
| 471 | |
| 472 | /* |
| 473 | * Handle stack alignment exceptions. |
| 474 | */ |
| 475 | asmlinkage void __exception do_sp_pc_abort(unsigned long addr, |
| 476 | unsigned int esr, |
| 477 | struct pt_regs *regs) |
| 478 | { |
| 479 | struct siginfo info; |
| 480 | |
| 481 | info.si_signo = SIGBUS; |
| 482 | info.si_errno = 0; |
| 483 | info.si_code = BUS_ADRALN; |
| 484 | info.si_addr = (void __user *)addr; |
| 485 | arm64_notify_die("", regs, &info, esr); |
| 486 | } |
| 487 | |
| 488 | static struct fault_info debug_fault_info[] = { |
| 489 | { do_bad, SIGTRAP, TRAP_HWBKPT, "hardware breakpoint" }, |
| 490 | { do_bad, SIGTRAP, TRAP_HWBKPT, "hardware single-step" }, |
| 491 | { do_bad, SIGTRAP, TRAP_HWBKPT, "hardware watchpoint" }, |
| 492 | { do_bad, SIGBUS, 0, "unknown 3" }, |
| 493 | { do_bad, SIGTRAP, TRAP_BRKPT, "aarch32 BKPT" }, |
| 494 | { do_bad, SIGTRAP, 0, "aarch32 vector catch" }, |
| 495 | { do_bad, SIGTRAP, TRAP_BRKPT, "aarch64 BRK" }, |
| 496 | { do_bad, SIGBUS, 0, "unknown 7" }, |
| 497 | }; |
| 498 | |
| 499 | void __init hook_debug_fault_code(int nr, |
| 500 | int (*fn)(unsigned long, unsigned int, struct pt_regs *), |
| 501 | int sig, int code, const char *name) |
| 502 | { |
| 503 | BUG_ON(nr < 0 || nr >= ARRAY_SIZE(debug_fault_info)); |
| 504 | |
| 505 | debug_fault_info[nr].fn = fn; |
| 506 | debug_fault_info[nr].sig = sig; |
| 507 | debug_fault_info[nr].code = code; |
| 508 | debug_fault_info[nr].name = name; |
| 509 | } |
| 510 | |
| 511 | asmlinkage int __exception do_debug_exception(unsigned long addr, |
| 512 | unsigned int esr, |
| 513 | struct pt_regs *regs) |
| 514 | { |
| 515 | const struct fault_info *inf = debug_fault_info + DBG_ESR_EVT(esr); |
| 516 | struct siginfo info; |
| 517 | |
| 518 | if (!inf->fn(addr, esr, regs)) |
| 519 | return 1; |
| 520 | |
| 521 | pr_alert("Unhandled debug exception: %s (0x%08x) at 0x%016lx\n", |
| 522 | inf->name, esr, addr); |
| 523 | |
| 524 | info.si_signo = inf->sig; |
| 525 | info.si_errno = 0; |
| 526 | info.si_code = inf->code; |
| 527 | info.si_addr = (void __user *)addr; |
| 528 | arm64_notify_die("", regs, &info, esr); |
| 529 | |
| 530 | return 0; |
| 531 | } |