Commit | Line | Data |
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5a0015d6 CZ |
1 | /* |
2 | * arch/xtensa/kernel/traps.c | |
3 | * | |
4 | * Exception handling. | |
5 | * | |
6 | * Derived from code with the following copyrights: | |
7 | * Copyright (C) 1994 - 1999 by Ralf Baechle | |
8 | * Modified for R3000 by Paul M. Antoine, 1995, 1996 | |
9 | * Complete output from die() by Ulf Carlsson, 1998 | |
10 | * Copyright (C) 1999 Silicon Graphics, Inc. | |
11 | * | |
12 | * Essentially rewritten for the Xtensa architecture port. | |
13 | * | |
3e4196a5 | 14 | * Copyright (C) 2001 - 2013 Tensilica Inc. |
5a0015d6 CZ |
15 | * |
16 | * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> | |
17 | * Chris Zankel <chris@zankel.net> | |
18 | * Marc Gauthier<marc@tensilica.com, marc@alumni.uwaterloo.ca> | |
19 | * Kevin Chea | |
20 | * | |
21 | * This file is subject to the terms and conditions of the GNU General Public | |
22 | * License. See the file "COPYING" in the main directory of this archive | |
23 | * for more details. | |
24 | */ | |
25 | ||
26 | #include <linux/kernel.h> | |
3f07c014 | 27 | #include <linux/sched/signal.h> |
b17b0153 | 28 | #include <linux/sched/debug.h> |
3f8c2452 | 29 | #include <linux/sched/task_stack.h> |
5a0015d6 CZ |
30 | #include <linux/init.h> |
31 | #include <linux/module.h> | |
32 | #include <linux/stringify.h> | |
33 | #include <linux/kallsyms.h> | |
5c888d53 | 34 | #include <linux/delay.h> |
5a891ed5 | 35 | #include <linux/hardirq.h> |
c130d3be | 36 | #include <linux/ratelimit.h> |
65fddcfc | 37 | #include <linux/pgtable.h> |
5a0015d6 | 38 | |
3e4196a5 | 39 | #include <asm/stacktrace.h> |
5a0015d6 CZ |
40 | #include <asm/ptrace.h> |
41 | #include <asm/timex.h> | |
7c0f6ba6 | 42 | #include <linux/uaccess.h> |
5a0015d6 | 43 | #include <asm/processor.h> |
2d6f82fe | 44 | #include <asm/traps.h> |
c91e02bd | 45 | #include <asm/hw_breakpoint.h> |
5a0015d6 | 46 | |
5a0015d6 CZ |
47 | /* |
48 | * Machine specific interrupt handlers | |
49 | */ | |
50 | ||
db0d07fa | 51 | static void do_illegal_instruction(struct pt_regs *regs); |
408b1d3c | 52 | static void do_div0(struct pt_regs *regs); |
db0d07fa MF |
53 | static void do_interrupt(struct pt_regs *regs); |
54 | #if XTENSA_FAKE_NMI | |
55 | static void do_nmi(struct pt_regs *regs); | |
56 | #endif | |
f29cf776 MF |
57 | #ifdef CONFIG_XTENSA_LOAD_STORE |
58 | static void do_load_store(struct pt_regs *regs); | |
59 | #endif | |
db0d07fa | 60 | static void do_unaligned_user(struct pt_regs *regs); |
db0d07fa | 61 | static void do_multihit(struct pt_regs *regs); |
11e969bc MF |
62 | #if XTENSA_HAVE_COPROCESSORS |
63 | static void do_coprocessor(struct pt_regs *regs); | |
64 | #endif | |
db0d07fa | 65 | static void do_debug(struct pt_regs *regs); |
5a0015d6 CZ |
66 | |
67 | /* | |
68 | * The vector table must be preceded by a save area (which | |
69 | * implies it must be in RAM, unless one places RAM immediately | |
70 | * before a ROM and puts the vector at the start of the ROM (!)) | |
71 | */ | |
72 | ||
73 | #define KRNL 0x01 | |
74 | #define USER 0x02 | |
75 | ||
76 | #define COPROCESSOR(x) \ | |
11e969bc MF |
77 | { EXCCAUSE_COPROCESSOR ## x ## _DISABLED, USER|KRNL, fast_coprocessor },\ |
78 | { EXCCAUSE_COPROCESSOR ## x ## _DISABLED, 0, do_coprocessor } | |
5a0015d6 CZ |
79 | |
80 | typedef struct { | |
81 | int cause; | |
82 | int fast; | |
83 | void* handler; | |
84 | } dispatch_init_table_t; | |
85 | ||
b91dc336 | 86 | static dispatch_init_table_t __initdata dispatch_init_table[] = { |
5a0015d6 | 87 | |
09f8a6db MF |
88 | #ifdef CONFIG_USER_ABI_CALL0_PROBE |
89 | { EXCCAUSE_ILLEGAL_INSTRUCTION, USER, fast_illegal_instruction_user }, | |
90 | #endif | |
173d6681 | 91 | { EXCCAUSE_ILLEGAL_INSTRUCTION, 0, do_illegal_instruction}, |
173d6681 CZ |
92 | { EXCCAUSE_SYSTEM_CALL, USER, fast_syscall_user }, |
93 | { EXCCAUSE_SYSTEM_CALL, 0, system_call }, | |
94 | /* EXCCAUSE_INSTRUCTION_FETCH unhandled */ | |
f29cf776 MF |
95 | #ifdef CONFIG_XTENSA_LOAD_STORE |
96 | { EXCCAUSE_LOAD_STORE_ERROR, USER|KRNL, fast_load_store }, | |
97 | { EXCCAUSE_LOAD_STORE_ERROR, 0, do_load_store }, | |
98 | #endif | |
173d6681 | 99 | { EXCCAUSE_LEVEL1_INTERRUPT, 0, do_interrupt }, |
da0a4e5c | 100 | #ifdef SUPPORT_WINDOWED |
173d6681 | 101 | { EXCCAUSE_ALLOCA, USER|KRNL, fast_alloca }, |
da0a4e5c | 102 | #endif |
408b1d3c | 103 | { EXCCAUSE_INTEGER_DIVIDE_BY_ZERO, 0, do_div0 }, |
173d6681 | 104 | /* EXCCAUSE_PRIVILEGED unhandled */ |
a160e941 MF |
105 | #if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION || \ |
106 | IS_ENABLED(CONFIG_XTENSA_LOAD_STORE) | |
4ded6282 | 107 | #ifdef CONFIG_XTENSA_UNALIGNED_USER |
173d6681 | 108 | { EXCCAUSE_UNALIGNED, USER, fast_unaligned }, |
5a0015d6 | 109 | #endif |
173d6681 | 110 | { EXCCAUSE_UNALIGNED, KRNL, fast_unaligned }, |
5a0015d6 | 111 | #endif |
3522bcfe | 112 | { EXCCAUSE_UNALIGNED, 0, do_unaligned_user }, |
e5083a63 | 113 | #ifdef CONFIG_MMU |
a8f0c31f MF |
114 | { EXCCAUSE_ITLB_MISS, 0, do_page_fault }, |
115 | { EXCCAUSE_ITLB_MISS, USER|KRNL, fast_second_level_miss}, | |
116 | { EXCCAUSE_DTLB_MISS, USER|KRNL, fast_second_level_miss}, | |
117 | { EXCCAUSE_DTLB_MISS, 0, do_page_fault }, | |
118 | { EXCCAUSE_STORE_CACHE_ATTRIBUTE, USER|KRNL, fast_store_prohibited }, | |
119 | #endif /* CONFIG_MMU */ | |
120 | #ifdef CONFIG_PFAULT | |
173d6681 | 121 | { EXCCAUSE_ITLB_MULTIHIT, 0, do_multihit }, |
a8f0c31f | 122 | { EXCCAUSE_ITLB_PRIVILEGE, 0, do_page_fault }, |
173d6681 | 123 | { EXCCAUSE_FETCH_CACHE_ATTRIBUTE, 0, do_page_fault }, |
173d6681 | 124 | { EXCCAUSE_DTLB_MULTIHIT, 0, do_multihit }, |
a8f0c31f | 125 | { EXCCAUSE_DTLB_PRIVILEGE, 0, do_page_fault }, |
173d6681 CZ |
126 | { EXCCAUSE_STORE_CACHE_ATTRIBUTE, 0, do_page_fault }, |
127 | { EXCCAUSE_LOAD_CACHE_ATTRIBUTE, 0, do_page_fault }, | |
a8f0c31f | 128 | #endif |
5a0015d6 | 129 | /* XCCHAL_EXCCAUSE_FLOATING_POINT unhandled */ |
c658eac6 | 130 | #if XTENSA_HAVE_COPROCESSOR(0) |
5a0015d6 CZ |
131 | COPROCESSOR(0), |
132 | #endif | |
c658eac6 | 133 | #if XTENSA_HAVE_COPROCESSOR(1) |
5a0015d6 CZ |
134 | COPROCESSOR(1), |
135 | #endif | |
c658eac6 | 136 | #if XTENSA_HAVE_COPROCESSOR(2) |
5a0015d6 CZ |
137 | COPROCESSOR(2), |
138 | #endif | |
c658eac6 | 139 | #if XTENSA_HAVE_COPROCESSOR(3) |
5a0015d6 CZ |
140 | COPROCESSOR(3), |
141 | #endif | |
c658eac6 | 142 | #if XTENSA_HAVE_COPROCESSOR(4) |
5a0015d6 CZ |
143 | COPROCESSOR(4), |
144 | #endif | |
c658eac6 | 145 | #if XTENSA_HAVE_COPROCESSOR(5) |
5a0015d6 CZ |
146 | COPROCESSOR(5), |
147 | #endif | |
c658eac6 | 148 | #if XTENSA_HAVE_COPROCESSOR(6) |
5a0015d6 CZ |
149 | COPROCESSOR(6), |
150 | #endif | |
c658eac6 | 151 | #if XTENSA_HAVE_COPROCESSOR(7) |
5a0015d6 CZ |
152 | COPROCESSOR(7), |
153 | #endif | |
38fef73c MF |
154 | #if XTENSA_FAKE_NMI |
155 | { EXCCAUSE_MAPPED_NMI, 0, do_nmi }, | |
156 | #endif | |
5a0015d6 CZ |
157 | { EXCCAUSE_MAPPED_DEBUG, 0, do_debug }, |
158 | { -1, -1, 0 } | |
159 | ||
160 | }; | |
161 | ||
162 | /* The exception table <exc_table> serves two functions: | |
163 | * 1. it contains three dispatch tables (fast_user, fast_kernel, default-c) | |
164 | * 2. it is a temporary memory buffer for the exception handlers. | |
165 | */ | |
166 | ||
f21a79ca | 167 | DEFINE_PER_CPU(struct exc_table, exc_table); |
6ec7026a MF |
168 | DEFINE_PER_CPU(struct debug_table, debug_table); |
169 | ||
5a0015d6 CZ |
170 | void die(const char*, struct pt_regs*, long); |
171 | ||
172 | static inline void | |
173 | __die_if_kernel(const char *str, struct pt_regs *regs, long err) | |
174 | { | |
175 | if (!user_mode(regs)) | |
176 | die(str, regs, err); | |
177 | } | |
178 | ||
f7667ca1 MF |
179 | #ifdef CONFIG_PRINT_USER_CODE_ON_UNHANDLED_EXCEPTION |
180 | static inline void dump_user_code(struct pt_regs *regs) | |
181 | { | |
182 | char buf[32]; | |
183 | ||
184 | if (copy_from_user(buf, (void __user *)(regs->pc & -16), sizeof(buf)) == 0) { | |
185 | print_hex_dump(KERN_INFO, " ", DUMP_PREFIX_NONE, | |
186 | 32, 1, buf, sizeof(buf), false); | |
187 | ||
188 | } | |
189 | } | |
190 | #else | |
191 | static inline void dump_user_code(struct pt_regs *regs) | |
192 | { | |
193 | } | |
194 | #endif | |
195 | ||
5a0015d6 CZ |
196 | /* |
197 | * Unhandled Exceptions. Kill user task or panic if in kernel space. | |
198 | */ | |
199 | ||
fc55402b | 200 | void do_unhandled(struct pt_regs *regs) |
5a0015d6 CZ |
201 | { |
202 | __die_if_kernel("Caught unhandled exception - should not happen", | |
c130d3be | 203 | regs, SIGKILL); |
5a0015d6 CZ |
204 | |
205 | /* If in user mode, send SIGILL signal to current process */ | |
c130d3be MF |
206 | pr_info_ratelimited("Caught unhandled exception in '%s' " |
207 | "(pid = %d, pc = %#010lx) - should not happen\n" | |
208 | "\tEXCCAUSE is %ld\n", | |
209 | current->comm, task_pid_nr(current), regs->pc, | |
fc55402b | 210 | regs->exccause); |
f7667ca1 | 211 | dump_user_code(regs); |
3cf5d076 | 212 | force_sig(SIGILL); |
5a0015d6 CZ |
213 | } |
214 | ||
215 | /* | |
216 | * Multi-hit exception. This if fatal! | |
217 | */ | |
218 | ||
db0d07fa | 219 | static void do_multihit(struct pt_regs *regs) |
5a0015d6 CZ |
220 | { |
221 | die("Caught multihit exception", regs, SIGKILL); | |
222 | } | |
223 | ||
224 | /* | |
2d1c645c | 225 | * IRQ handler. |
5a0015d6 CZ |
226 | */ |
227 | ||
38fef73c MF |
228 | #if XTENSA_FAKE_NMI |
229 | ||
e4629194 MF |
230 | #define IS_POW2(v) (((v) & ((v) - 1)) == 0) |
231 | ||
232 | #if !(PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \ | |
233 | IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL))) | |
234 | #warning "Fake NMI is requested for PMM, but there are other IRQs at or above its level." | |
235 | #warning "Fake NMI will be used, but there will be a bugcheck if one of those IRQs fire." | |
236 | ||
237 | static inline void check_valid_nmi(void) | |
238 | { | |
cad6fade MF |
239 | unsigned intread = xtensa_get_sr(interrupt); |
240 | unsigned intenable = xtensa_get_sr(intenable); | |
e4629194 MF |
241 | |
242 | BUG_ON(intread & intenable & | |
243 | ~(XTENSA_INTLEVEL_ANDBELOW_MASK(PROFILING_INTLEVEL) ^ | |
244 | XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL) ^ | |
245 | BIT(XCHAL_PROFILING_INTERRUPT))); | |
246 | } | |
247 | ||
248 | #else | |
249 | ||
250 | static inline void check_valid_nmi(void) | |
251 | { | |
252 | } | |
253 | ||
254 | #endif | |
255 | ||
38fef73c MF |
256 | irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id); |
257 | ||
258 | DEFINE_PER_CPU(unsigned long, nmi_count); | |
259 | ||
db0d07fa | 260 | static void do_nmi(struct pt_regs *regs) |
38fef73c | 261 | { |
de4415d0 | 262 | struct pt_regs *old_regs = set_irq_regs(regs); |
38fef73c | 263 | |
38fef73c MF |
264 | nmi_enter(); |
265 | ++*this_cpu_ptr(&nmi_count); | |
e4629194 | 266 | check_valid_nmi(); |
38fef73c MF |
267 | xtensa_pmu_irq_handler(0, NULL); |
268 | nmi_exit(); | |
269 | set_irq_regs(old_regs); | |
270 | } | |
271 | #endif | |
272 | ||
db0d07fa | 273 | static void do_interrupt(struct pt_regs *regs) |
5a0015d6 | 274 | { |
2d1c645c MG |
275 | static const unsigned int_level_mask[] = { |
276 | 0, | |
277 | XCHAL_INTLEVEL1_MASK, | |
278 | XCHAL_INTLEVEL2_MASK, | |
279 | XCHAL_INTLEVEL3_MASK, | |
280 | XCHAL_INTLEVEL4_MASK, | |
281 | XCHAL_INTLEVEL5_MASK, | |
282 | XCHAL_INTLEVEL6_MASK, | |
283 | XCHAL_INTLEVEL7_MASK, | |
284 | }; | |
de4415d0 | 285 | struct pt_regs *old_regs = set_irq_regs(regs); |
43ba2237 | 286 | unsigned unhandled = ~0u; |
99623239 MF |
287 | |
288 | irq_enter(); | |
5a0015d6 | 289 | |
2d1c645c | 290 | for (;;) { |
cad6fade MF |
291 | unsigned intread = xtensa_get_sr(interrupt); |
292 | unsigned intenable = xtensa_get_sr(intenable); | |
895666a9 MF |
293 | unsigned int_at_level = intread & intenable; |
294 | unsigned level; | |
295 | ||
296 | for (level = LOCKLEVEL; level > 0; --level) { | |
297 | if (int_at_level & int_level_mask[level]) { | |
298 | int_at_level &= int_level_mask[level]; | |
43ba2237 MF |
299 | if (int_at_level & unhandled) |
300 | int_at_level &= unhandled; | |
301 | else | |
302 | unhandled |= int_level_mask[level]; | |
895666a9 MF |
303 | break; |
304 | } | |
305 | } | |
2d1c645c | 306 | |
895666a9 | 307 | if (level == 0) |
99623239 MF |
308 | break; |
309 | ||
43ba2237 MF |
310 | /* clear lowest pending irq in the unhandled mask */ |
311 | unhandled ^= (int_at_level & -int_at_level); | |
99623239 | 312 | do_IRQ(__ffs(int_at_level), regs); |
5a0015d6 | 313 | } |
99623239 MF |
314 | |
315 | irq_exit(); | |
316 | set_irq_regs(old_regs); | |
5a0015d6 CZ |
317 | } |
318 | ||
d7486200 MF |
319 | static bool check_div0(struct pt_regs *regs) |
320 | { | |
321 | static const u8 pattern[] = {'D', 'I', 'V', '0'}; | |
322 | const u8 *p; | |
323 | u8 buf[5]; | |
324 | ||
325 | if (user_mode(regs)) { | |
326 | if (copy_from_user(buf, (void __user *)regs->pc + 2, 5)) | |
dc60001e | 327 | return false; |
d7486200 MF |
328 | p = buf; |
329 | } else { | |
330 | p = (const u8 *)regs->pc + 2; | |
331 | } | |
332 | ||
333 | return memcmp(p, pattern, sizeof(pattern)) == 0 || | |
334 | memcmp(p + 1, pattern, sizeof(pattern)) == 0; | |
335 | } | |
336 | ||
5a0015d6 CZ |
337 | /* |
338 | * Illegal instruction. Fatal if in kernel space. | |
339 | */ | |
340 | ||
db0d07fa | 341 | static void do_illegal_instruction(struct pt_regs *regs) |
5a0015d6 | 342 | { |
5cc5f19f MF |
343 | #ifdef CONFIG_USER_ABI_CALL0_PROBE |
344 | /* | |
345 | * When call0 application encounters an illegal instruction fast | |
346 | * exception handler will attempt to set PS.WOE and retry failing | |
347 | * instruction. | |
348 | * If we get here we know that that instruction is also illegal | |
349 | * with PS.WOE set, so it's not related to the windowed option | |
350 | * hence PS.WOE may be cleared. | |
351 | */ | |
352 | if (regs->pc == current_thread_info()->ps_woe_fix_addr) | |
353 | regs->ps &= ~PS_WOE_MASK; | |
354 | #endif | |
d7486200 MF |
355 | if (check_div0(regs)) { |
356 | do_div0(regs); | |
357 | return; | |
358 | } | |
359 | ||
5a0015d6 CZ |
360 | __die_if_kernel("Illegal instruction in kernel", regs, SIGKILL); |
361 | ||
362 | /* If in user mode, send SIGILL signal to current process. */ | |
363 | ||
c130d3be MF |
364 | pr_info_ratelimited("Illegal Instruction in '%s' (pid = %d, pc = %#010lx)\n", |
365 | current->comm, task_pid_nr(current), regs->pc); | |
3cf5d076 | 366 | force_sig(SIGILL); |
5a0015d6 CZ |
367 | } |
368 | ||
408b1d3c MF |
369 | static void do_div0(struct pt_regs *regs) |
370 | { | |
371 | __die_if_kernel("Unhandled division by 0 in kernel", regs, SIGKILL); | |
372 | force_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)regs->pc); | |
373 | } | |
5a0015d6 | 374 | |
f29cf776 MF |
375 | #ifdef CONFIG_XTENSA_LOAD_STORE |
376 | static void do_load_store(struct pt_regs *regs) | |
377 | { | |
378 | __die_if_kernel("Unhandled load/store exception in kernel", | |
379 | regs, SIGKILL); | |
380 | ||
381 | pr_info_ratelimited("Load/store error to %08lx in '%s' (pid = %d, pc = %#010lx)\n", | |
382 | regs->excvaddr, current->comm, | |
383 | task_pid_nr(current), regs->pc); | |
384 | force_sig_fault(SIGBUS, BUS_ADRERR, (void *)regs->excvaddr); | |
385 | } | |
386 | #endif | |
387 | ||
5a0015d6 CZ |
388 | /* |
389 | * Handle unaligned memory accesses from user space. Kill task. | |
390 | * | |
391 | * If CONFIG_UNALIGNED_USER is not set, we don't allow unaligned memory | |
392 | * accesses causes from user space. | |
393 | */ | |
394 | ||
db0d07fa | 395 | static void do_unaligned_user(struct pt_regs *regs) |
5a0015d6 | 396 | { |
5a0015d6 | 397 | __die_if_kernel("Unhandled unaligned exception in kernel", |
c130d3be | 398 | regs, SIGKILL); |
5a0015d6 | 399 | |
c130d3be MF |
400 | pr_info_ratelimited("Unaligned memory access to %08lx in '%s' " |
401 | "(pid = %d, pc = %#010lx)\n", | |
402 | regs->excvaddr, current->comm, | |
403 | task_pid_nr(current), regs->pc); | |
2e1661d2 | 404 | force_sig_fault(SIGBUS, BUS_ADRALN, (void *) regs->excvaddr); |
5a0015d6 | 405 | } |
5a0015d6 | 406 | |
11e969bc MF |
407 | #if XTENSA_HAVE_COPROCESSORS |
408 | static void do_coprocessor(struct pt_regs *regs) | |
409 | { | |
410 | coprocessor_flush_release_all(current_thread_info()); | |
411 | } | |
412 | #endif | |
413 | ||
c91e02bd MF |
414 | /* Handle debug events. |
415 | * When CONFIG_HAVE_HW_BREAKPOINT is on this handler is called with | |
416 | * preemption disabled to avoid rescheduling and keep mapping of hardware | |
417 | * breakpoint structures to debug registers intact, so that | |
418 | * DEBUGCAUSE.DBNUM could be used in case of data breakpoint hit. | |
419 | */ | |
db0d07fa | 420 | static void do_debug(struct pt_regs *regs) |
5a0015d6 | 421 | { |
c91e02bd MF |
422 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
423 | int ret = check_hw_breakpoint(regs); | |
424 | ||
425 | preempt_enable(); | |
426 | if (ret == 0) | |
427 | return; | |
428 | #endif | |
5a0015d6 CZ |
429 | __die_if_kernel("Breakpoint in kernel", regs, SIGKILL); |
430 | ||
431 | /* If in user mode, send SIGTRAP signal to current process */ | |
432 | ||
3cf5d076 | 433 | force_sig(SIGTRAP); |
5a0015d6 CZ |
434 | } |
435 | ||
436 | ||
f21a79ca MF |
437 | #define set_handler(type, cause, handler) \ |
438 | do { \ | |
439 | unsigned int cpu; \ | |
440 | \ | |
441 | for_each_possible_cpu(cpu) \ | |
442 | per_cpu(exc_table, cpu).type[cause] = (handler);\ | |
443 | } while (0) | |
f615136c | 444 | |
28570e8d MF |
445 | /* Set exception C handler - for temporary use when probing exceptions */ |
446 | ||
fc55402b MF |
447 | xtensa_exception_handler * |
448 | __init trap_set_handler(int cause, xtensa_exception_handler *handler) | |
28570e8d | 449 | { |
f21a79ca MF |
450 | void *previous = per_cpu(exc_table, 0).default_handler[cause]; |
451 | ||
452 | set_handler(default_handler, cause, handler); | |
28570e8d MF |
453 | return previous; |
454 | } | |
455 | ||
456 | ||
49b424fe | 457 | static void trap_init_excsave(void) |
f615136c | 458 | { |
9fa8c59f | 459 | xtensa_set_sr(this_cpu_ptr(&exc_table), excsave1); |
f615136c MF |
460 | } |
461 | ||
6ec7026a MF |
462 | static void trap_init_debug(void) |
463 | { | |
464 | unsigned long debugsave = (unsigned long)this_cpu_ptr(&debug_table); | |
465 | ||
466 | this_cpu_ptr(&debug_table)->debug_exception = debug_exception; | |
467 | __asm__ __volatile__("wsr %0, excsave" __stringify(XCHAL_DEBUGLEVEL) | |
468 | :: "a"(debugsave)); | |
469 | } | |
470 | ||
5a0015d6 CZ |
471 | /* |
472 | * Initialize dispatch tables. | |
473 | * | |
474 | * The exception vectors are stored compressed the __init section in the | |
475 | * dispatch_init_table. This function initializes the following three tables | |
476 | * from that compressed table: | |
477 | * - fast user first dispatch table for user exceptions | |
478 | * - fast kernel first dispatch table for kernel exceptions | |
479 | * - default C-handler C-handler called by the default fast handler. | |
480 | * | |
481 | * See vectors.S for more details. | |
482 | */ | |
483 | ||
b91dc336 | 484 | void __init trap_init(void) |
5a0015d6 CZ |
485 | { |
486 | int i; | |
487 | ||
488 | /* Setup default vectors. */ | |
489 | ||
f21a79ca MF |
490 | for (i = 0; i < EXCCAUSE_N; i++) { |
491 | set_handler(fast_user_handler, i, user_exception); | |
492 | set_handler(fast_kernel_handler, i, kernel_exception); | |
493 | set_handler(default_handler, i, do_unhandled); | |
5a0015d6 CZ |
494 | } |
495 | ||
496 | /* Setup specific handlers. */ | |
497 | ||
498 | for(i = 0; dispatch_init_table[i].cause >= 0; i++) { | |
5a0015d6 CZ |
499 | int fast = dispatch_init_table[i].fast; |
500 | int cause = dispatch_init_table[i].cause; | |
501 | void *handler = dispatch_init_table[i].handler; | |
502 | ||
503 | if (fast == 0) | |
f21a79ca | 504 | set_handler(default_handler, cause, handler); |
60deebe6 | 505 | if ((fast & USER) != 0) |
f21a79ca | 506 | set_handler(fast_user_handler, cause, handler); |
60deebe6 | 507 | if ((fast & KRNL) != 0) |
f21a79ca | 508 | set_handler(fast_kernel_handler, cause, handler); |
5a0015d6 CZ |
509 | } |
510 | ||
511 | /* Initialize EXCSAVE_1 to hold the address of the exception table. */ | |
f615136c | 512 | trap_init_excsave(); |
6ec7026a | 513 | trap_init_debug(); |
f615136c | 514 | } |
5a0015d6 | 515 | |
f615136c | 516 | #ifdef CONFIG_SMP |
49b424fe | 517 | void secondary_trap_init(void) |
f615136c MF |
518 | { |
519 | trap_init_excsave(); | |
6ec7026a | 520 | trap_init_debug(); |
5a0015d6 | 521 | } |
f615136c | 522 | #endif |
5a0015d6 CZ |
523 | |
524 | /* | |
525 | * This function dumps the current valid window frame and other base registers. | |
526 | */ | |
527 | ||
528 | void show_regs(struct pt_regs * regs) | |
529 | { | |
431d1a34 | 530 | int i; |
5a0015d6 | 531 | |
a43cb95d TH |
532 | show_regs_print_info(KERN_DEFAULT); |
533 | ||
8d7e8240 | 534 | for (i = 0; i < 16; i++) { |
5a0015d6 | 535 | if ((i % 8) == 0) |
d4eccafc MF |
536 | pr_info("a%02d:", i); |
537 | pr_cont(" %08lx", regs->areg[i]); | |
5a0015d6 | 538 | } |
d4eccafc MF |
539 | pr_cont("\n"); |
540 | pr_info("pc: %08lx, ps: %08lx, depc: %08lx, excvaddr: %08lx\n", | |
541 | regs->pc, regs->ps, regs->depc, regs->excvaddr); | |
542 | pr_info("lbeg: %08lx, lend: %08lx lcount: %08lx, sar: %08lx\n", | |
543 | regs->lbeg, regs->lend, regs->lcount, regs->sar); | |
5a0015d6 | 544 | if (user_mode(regs)) |
d4eccafc MF |
545 | pr_cont("wb: %08lx, ws: %08lx, wmask: %08lx, syscall: %ld\n", |
546 | regs->windowbase, regs->windowstart, regs->wmask, | |
547 | regs->syscall); | |
5a0015d6 CZ |
548 | } |
549 | ||
3e4196a5 | 550 | static int show_trace_cb(struct stackframe *frame, void *data) |
586411dc | 551 | { |
47fb7029 DS |
552 | const char *loglvl = data; |
553 | ||
e640cc30 | 554 | if (kernel_text_address(frame->pc)) |
47fb7029 DS |
555 | printk("%s [<%08lx>] %pB\n", |
556 | loglvl, frame->pc, (void *)frame->pc); | |
3e4196a5 | 557 | return 0; |
586411dc JW |
558 | } |
559 | ||
47fb7029 DS |
560 | static void show_trace(struct task_struct *task, unsigned long *sp, |
561 | const char *loglvl) | |
5a0015d6 | 562 | { |
3e4196a5 MF |
563 | if (!sp) |
564 | sp = stack_pointer(task); | |
5a0015d6 | 565 | |
47fb7029 DS |
566 | printk("%sCall Trace:\n", loglvl); |
567 | walk_stackframe(sp, show_trace_cb, (void *)loglvl); | |
5a0015d6 CZ |
568 | } |
569 | ||
c5fccebc | 570 | #define STACK_DUMP_ENTRY_SIZE 4 |
cc34f290 | 571 | #define STACK_DUMP_LINE_SIZE 16 |
8951eb15 | 572 | static size_t kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH; |
5a0015d6 | 573 | |
cc34f290 | 574 | struct stack_fragment |
5a0015d6 | 575 | { |
cc34f290 MF |
576 | size_t len; |
577 | size_t off; | |
578 | u8 *sp; | |
579 | const char *loglvl; | |
580 | }; | |
5a0015d6 | 581 | |
cc34f290 MF |
582 | static int show_stack_fragment_cb(struct stackframe *frame, void *data) |
583 | { | |
584 | struct stack_fragment *sf = data; | |
5a0015d6 | 585 | |
cc34f290 | 586 | while (sf->off < sf->len) { |
1d3b7a78 | 587 | u8 line[STACK_DUMP_LINE_SIZE]; |
cc34f290 MF |
588 | size_t line_len = sf->len - sf->off > STACK_DUMP_LINE_SIZE ? |
589 | STACK_DUMP_LINE_SIZE : sf->len - sf->off; | |
590 | bool arrow = sf->off == 0; | |
1d3b7a78 | 591 | |
cc34f290 MF |
592 | if (frame && frame->sp == (unsigned long)(sf->sp + sf->off)) |
593 | arrow = true; | |
594 | ||
595 | __memcpy(line, sf->sp + sf->off, line_len); | |
596 | print_hex_dump(sf->loglvl, arrow ? "> " : " ", DUMP_PREFIX_NONE, | |
1d3b7a78 MF |
597 | STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE, |
598 | line, line_len, false); | |
cc34f290 MF |
599 | sf->off += STACK_DUMP_LINE_SIZE; |
600 | if (arrow) | |
601 | return 0; | |
1d3b7a78 | 602 | } |
cc34f290 MF |
603 | return 1; |
604 | } | |
605 | ||
606 | void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl) | |
607 | { | |
608 | struct stack_fragment sf; | |
609 | ||
610 | if (!sp) | |
611 | sp = stack_pointer(task); | |
612 | ||
613 | sf.len = min((-(size_t)sp) & (THREAD_SIZE - STACK_DUMP_ENTRY_SIZE), | |
614 | kstack_depth_to_print * STACK_DUMP_ENTRY_SIZE); | |
615 | sf.off = 0; | |
616 | sf.sp = (u8 *)sp; | |
617 | sf.loglvl = loglvl; | |
618 | ||
619 | printk("%sStack:\n", loglvl); | |
620 | walk_stackframe(sp, show_stack_fragment_cb, &sf); | |
621 | while (sf.off < sf.len) | |
622 | show_stack_fragment_cb(NULL, &sf); | |
20da1e8b DS |
623 | show_trace(task, sp, loglvl); |
624 | } | |
625 | ||
34af946a | 626 | DEFINE_SPINLOCK(die_lock); |
5a0015d6 | 627 | |
9fd5a04d | 628 | void __noreturn die(const char * str, struct pt_regs * regs, long err) |
5a0015d6 CZ |
629 | { |
630 | static int die_counter; | |
6c5260d7 TG |
631 | const char *pr = ""; |
632 | ||
633 | if (IS_ENABLED(CONFIG_PREEMPTION)) | |
634 | pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT"; | |
5a0015d6 CZ |
635 | |
636 | console_verbose(); | |
637 | spin_lock_irq(&die_lock); | |
638 | ||
6c5260d7 | 639 | pr_info("%s: sig: %ld [#%d]%s\n", str, err, ++die_counter, pr); |
5a0015d6 CZ |
640 | show_regs(regs); |
641 | if (!user_mode(regs)) | |
9cb8f069 | 642 | show_stack(NULL, (unsigned long *)regs->areg[1], KERN_INFO); |
5a0015d6 | 643 | |
373d4d09 | 644 | add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); |
5a0015d6 CZ |
645 | spin_unlock_irq(&die_lock); |
646 | ||
647 | if (in_interrupt()) | |
648 | panic("Fatal exception in interrupt"); | |
649 | ||
cea6a4ba | 650 | if (panic_on_oops) |
012c437d | 651 | panic("Fatal exception"); |
cea6a4ba | 652 | |
0e25498f | 653 | make_task_dead(err); |
5a0015d6 | 654 | } |