xref: /optee_os/core/arch/arm/kernel/abort.c (revision a1d5c81f8834a9d2c6f4372cce2e59e70e709121)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  */
5 
6 #include <arm.h>
7 #include <kernel/abort.h>
8 #include <kernel/misc.h>
9 #include <kernel/panic.h>
10 #include <kernel/tee_ta_manager.h>
11 #include <kernel/user_mode_ctx.h>
12 #include <mm/core_mmu.h>
13 #include <mm/mobj.h>
14 #include <mm/tee_pager.h>
15 #include <tee/tee_svc.h>
16 #include <trace.h>
17 #include <unw/unwind.h>
18 
19 #include "thread_private.h"
20 
21 enum fault_type {
22 	FAULT_TYPE_USER_TA_PANIC,
23 	FAULT_TYPE_USER_TA_VFP,
24 	FAULT_TYPE_PAGEABLE,
25 	FAULT_TYPE_IGNORE,
26 };
27 
28 #ifdef CFG_UNWIND
29 
30 #ifdef ARM32
31 /*
32  * Kernel or user mode unwind (32-bit execution state).
33  */
34 static void __print_stack_unwind(struct abort_info *ai)
35 {
36 	struct unwind_state_arm32 state = { };
37 	uint32_t mode = ai->regs->spsr & CPSR_MODE_MASK;
38 	uint32_t sp = 0;
39 	uint32_t lr = 0;
40 
41 	assert(!abort_is_user_exception(ai));
42 
43 	if (mode == CPSR_MODE_SYS) {
44 		sp = ai->regs->usr_sp;
45 		lr = ai->regs->usr_lr;
46 	} else {
47 		sp = read_mode_sp(mode);
48 		lr = read_mode_lr(mode);
49 	}
50 
51 	memset(&state, 0, sizeof(state));
52 	state.registers[0] = ai->regs->r0;
53 	state.registers[1] = ai->regs->r1;
54 	state.registers[2] = ai->regs->r2;
55 	state.registers[3] = ai->regs->r3;
56 	state.registers[4] = ai->regs->r4;
57 	state.registers[5] = ai->regs->r5;
58 	state.registers[6] = ai->regs->r6;
59 	state.registers[7] = ai->regs->r7;
60 	state.registers[8] = ai->regs->r8;
61 	state.registers[9] = ai->regs->r9;
62 	state.registers[10] = ai->regs->r10;
63 	state.registers[11] = ai->regs->r11;
64 	state.registers[13] = sp;
65 	state.registers[14] = lr;
66 	state.registers[15] = ai->pc;
67 
68 	print_stack_arm32(&state, thread_stack_start(), thread_stack_size());
69 }
70 #endif /* ARM32 */
71 
72 #ifdef ARM64
73 /* Kernel mode unwind (64-bit execution state) */
74 static void __print_stack_unwind(struct abort_info *ai)
75 {
76 	struct unwind_state_arm64 state = {
77 		.pc = ai->regs->elr,
78 		.fp = ai->regs->x29,
79 	};
80 
81 	print_stack_arm64(&state, thread_stack_start(), thread_stack_size());
82 }
83 #endif /*ARM64*/
84 
85 #else /* CFG_UNWIND */
86 static void __print_stack_unwind(struct abort_info *ai __unused)
87 {
88 }
89 #endif /* CFG_UNWIND */
90 
91 static __maybe_unused const char *abort_type_to_str(uint32_t abort_type)
92 {
93 	if (abort_type == ABORT_TYPE_DATA)
94 		return "data";
95 	if (abort_type == ABORT_TYPE_PREFETCH)
96 		return "prefetch";
97 	return "undef";
98 }
99 
100 static __maybe_unused const char *fault_to_str(uint32_t abort_type,
101 			uint32_t fault_descr)
102 {
103 	/* fault_descr is only valid for data or prefetch abort */
104 	if (abort_type != ABORT_TYPE_DATA && abort_type != ABORT_TYPE_PREFETCH)
105 		return "";
106 
107 	switch (core_mmu_get_fault_type(fault_descr)) {
108 	case CORE_MMU_FAULT_ALIGNMENT:
109 		return " (alignment fault)";
110 	case CORE_MMU_FAULT_TRANSLATION:
111 		return " (translation fault)";
112 	case CORE_MMU_FAULT_READ_PERMISSION:
113 		return " (read permission fault)";
114 	case CORE_MMU_FAULT_WRITE_PERMISSION:
115 		return " (write permission fault)";
116 	default:
117 		return "";
118 	}
119 }
120 
121 static __maybe_unused void
122 __print_abort_info(struct abort_info *ai __maybe_unused,
123 		   const char *ctx __maybe_unused)
124 {
125 	__maybe_unused size_t core_pos = 0;
126 #ifdef ARM32
127 	uint32_t mode = ai->regs->spsr & CPSR_MODE_MASK;
128 	__maybe_unused uint32_t sp = 0;
129 	__maybe_unused uint32_t lr = 0;
130 
131 	if (mode == CPSR_MODE_USR || mode == CPSR_MODE_SYS) {
132 		sp = ai->regs->usr_sp;
133 		lr = ai->regs->usr_lr;
134 		core_pos = thread_get_tsd()->abort_core;
135 	} else {
136 		sp = read_mode_sp(mode);
137 		lr = read_mode_lr(mode);
138 		core_pos = get_core_pos();
139 	}
140 #endif /*ARM32*/
141 #ifdef ARM64
142 	if (abort_is_user_exception(ai))
143 		core_pos = thread_get_tsd()->abort_core;
144 	else
145 		core_pos = get_core_pos();
146 #endif /*ARM64*/
147 
148 	EMSG_RAW("");
149 	EMSG_RAW("%s %s-abort at address 0x%" PRIxVA "%s",
150 		ctx, abort_type_to_str(ai->abort_type), ai->va,
151 		fault_to_str(ai->abort_type, ai->fault_descr));
152 #ifdef ARM32
153 	EMSG_RAW(" fsr 0x%08x  ttbr0 0x%08x  ttbr1 0x%08x  cidr 0x%X",
154 		 ai->fault_descr, read_ttbr0(), read_ttbr1(),
155 		 read_contextidr());
156 	EMSG_RAW(" cpu #%zu          cpsr 0x%08x",
157 		 core_pos, ai->regs->spsr);
158 	EMSG_RAW(" r0 0x%08x      r4 0x%08x    r8 0x%08x   r12 0x%08x",
159 		 ai->regs->r0, ai->regs->r4, ai->regs->r8, ai->regs->ip);
160 	EMSG_RAW(" r1 0x%08x      r5 0x%08x    r9 0x%08x    sp 0x%08x",
161 		 ai->regs->r1, ai->regs->r5, ai->regs->r9, sp);
162 	EMSG_RAW(" r2 0x%08x      r6 0x%08x   r10 0x%08x    lr 0x%08x",
163 		 ai->regs->r2, ai->regs->r6, ai->regs->r10, lr);
164 	EMSG_RAW(" r3 0x%08x      r7 0x%08x   r11 0x%08x    pc 0x%08x",
165 		 ai->regs->r3, ai->regs->r7, ai->regs->r11, ai->pc);
166 #endif /*ARM32*/
167 #ifdef ARM64
168 	EMSG_RAW(" esr 0x%08x  ttbr0 0x%08" PRIx64 "   ttbr1 0x%08" PRIx64
169 		 "   cidr 0x%X", ai->fault_descr, read_ttbr0_el1(),
170 		 read_ttbr1_el1(), read_contextidr_el1());
171 	EMSG_RAW(" cpu #%zu          cpsr 0x%08x",
172 		 core_pos, (uint32_t)ai->regs->spsr);
173 	EMSG_RAW(" x0  %016" PRIx64 " x1  %016" PRIx64,
174 		 ai->regs->x0, ai->regs->x1);
175 	EMSG_RAW(" x2  %016" PRIx64 " x3  %016" PRIx64,
176 		 ai->regs->x2, ai->regs->x3);
177 	EMSG_RAW(" x4  %016" PRIx64 " x5  %016" PRIx64,
178 		 ai->regs->x4, ai->regs->x5);
179 	EMSG_RAW(" x6  %016" PRIx64 " x7  %016" PRIx64,
180 		 ai->regs->x6, ai->regs->x7);
181 	EMSG_RAW(" x8  %016" PRIx64 " x9  %016" PRIx64,
182 		 ai->regs->x8, ai->regs->x9);
183 	EMSG_RAW(" x10 %016" PRIx64 " x11 %016" PRIx64,
184 		 ai->regs->x10, ai->regs->x11);
185 	EMSG_RAW(" x12 %016" PRIx64 " x13 %016" PRIx64,
186 		 ai->regs->x12, ai->regs->x13);
187 	EMSG_RAW(" x14 %016" PRIx64 " x15 %016" PRIx64,
188 		 ai->regs->x14, ai->regs->x15);
189 	EMSG_RAW(" x16 %016" PRIx64 " x17 %016" PRIx64,
190 		 ai->regs->x16, ai->regs->x17);
191 	EMSG_RAW(" x18 %016" PRIx64 " x19 %016" PRIx64,
192 		 ai->regs->x18, ai->regs->x19);
193 	EMSG_RAW(" x20 %016" PRIx64 " x21 %016" PRIx64,
194 		 ai->regs->x20, ai->regs->x21);
195 	EMSG_RAW(" x22 %016" PRIx64 " x23 %016" PRIx64,
196 		 ai->regs->x22, ai->regs->x23);
197 	EMSG_RAW(" x24 %016" PRIx64 " x25 %016" PRIx64,
198 		 ai->regs->x24, ai->regs->x25);
199 	EMSG_RAW(" x26 %016" PRIx64 " x27 %016" PRIx64,
200 		 ai->regs->x26, ai->regs->x27);
201 	EMSG_RAW(" x28 %016" PRIx64 " x29 %016" PRIx64,
202 		 ai->regs->x28, ai->regs->x29);
203 	EMSG_RAW(" x30 %016" PRIx64 " elr %016" PRIx64,
204 		 ai->regs->x30, ai->regs->elr);
205 	EMSG_RAW(" sp_el0 %016" PRIx64, ai->regs->sp_el0);
206 #endif /*ARM64*/
207 }
208 
209 /*
210  * Print abort info and (optionally) stack dump to the console
211  * @ai kernel-mode abort info.
212  * @stack_dump true to show a stack trace
213  */
214 static void __abort_print(struct abort_info *ai, bool stack_dump)
215 {
216 	assert(!abort_is_user_exception(ai));
217 
218 	__print_abort_info(ai, "Core");
219 
220 	if (stack_dump)
221 		__print_stack_unwind(ai);
222 }
223 
224 void abort_print(struct abort_info *ai)
225 {
226 	__abort_print(ai, false);
227 }
228 
229 void abort_print_error(struct abort_info *ai)
230 {
231 	__abort_print(ai, true);
232 }
233 
234 /* This function must be called from a normal thread */
235 void abort_print_current_ta(void)
236 {
237 	struct thread_specific_data *tsd = thread_get_tsd();
238 	struct abort_info ai = { };
239 	struct tee_ta_session *s = NULL;
240 
241 	if (tee_ta_get_current_session(&s) != TEE_SUCCESS)
242 		panic();
243 
244 	ai.abort_type = tsd->abort_type;
245 	ai.fault_descr = tsd->abort_descr;
246 	ai.va = tsd->abort_va;
247 	ai.pc = tsd->abort_regs.elr;
248 	ai.regs = &tsd->abort_regs;
249 
250 	if (ai.abort_type != ABORT_TYPE_TA_PANIC)
251 		__print_abort_info(&ai, "User TA");
252 
253 	s->ctx->ops->dump_state(s->ctx);
254 
255 #if defined(CFG_FTRACE_SUPPORT)
256 	if (s->ctx->ops->dump_ftrace) {
257 		s->fbuf = NULL;
258 		s->ctx->ops->dump_ftrace(s->ctx);
259 	}
260 #endif
261 }
262 
263 static void save_abort_info_in_tsd(struct abort_info *ai)
264 {
265 	struct thread_specific_data *tsd = thread_get_tsd();
266 
267 	tsd->abort_type = ai->abort_type;
268 	tsd->abort_descr = ai->fault_descr;
269 	tsd->abort_va = ai->va;
270 	tsd->abort_regs = *ai->regs;
271 	tsd->abort_core = get_core_pos();
272 }
273 
274 #ifdef ARM32
275 static void set_abort_info(uint32_t abort_type, struct thread_abort_regs *regs,
276 		struct abort_info *ai)
277 {
278 	switch (abort_type) {
279 	case ABORT_TYPE_DATA:
280 		ai->fault_descr = read_dfsr();
281 		ai->va = read_dfar();
282 		break;
283 	case ABORT_TYPE_PREFETCH:
284 		ai->fault_descr = read_ifsr();
285 		ai->va = read_ifar();
286 		break;
287 	default:
288 		ai->fault_descr = 0;
289 		ai->va = regs->elr;
290 		break;
291 	}
292 	ai->abort_type = abort_type;
293 	ai->pc = regs->elr;
294 	ai->regs = regs;
295 }
296 #endif /*ARM32*/
297 
298 #ifdef ARM64
299 static void set_abort_info(uint32_t abort_type __unused,
300 		struct thread_abort_regs *regs, struct abort_info *ai)
301 {
302 	ai->fault_descr = read_esr_el1();
303 	switch ((ai->fault_descr >> ESR_EC_SHIFT) & ESR_EC_MASK) {
304 	case ESR_EC_IABT_EL0:
305 	case ESR_EC_IABT_EL1:
306 		ai->abort_type = ABORT_TYPE_PREFETCH;
307 		ai->va = read_far_el1();
308 		break;
309 	case ESR_EC_DABT_EL0:
310 	case ESR_EC_DABT_EL1:
311 	case ESR_EC_SP_ALIGN:
312 		ai->abort_type = ABORT_TYPE_DATA;
313 		ai->va = read_far_el1();
314 		break;
315 	default:
316 		ai->abort_type = ABORT_TYPE_UNDEF;
317 		ai->va = regs->elr;
318 	}
319 	ai->pc = regs->elr;
320 	ai->regs = regs;
321 }
322 #endif /*ARM64*/
323 
324 #ifdef ARM32
325 static void handle_user_ta_panic(struct abort_info *ai)
326 {
327 	/*
328 	 * It was a user exception, stop user execution and return
329 	 * to TEE Core.
330 	 */
331 	ai->regs->r0 = TEE_ERROR_TARGET_DEAD;
332 	ai->regs->r1 = true;
333 	ai->regs->r2 = 0xdeadbeef;
334 	ai->regs->elr = (uint32_t)thread_unwind_user_mode;
335 	ai->regs->spsr &= CPSR_FIA;
336 	ai->regs->spsr &= ~CPSR_MODE_MASK;
337 	ai->regs->spsr |= CPSR_MODE_SVC;
338 	/* Select Thumb or ARM mode */
339 	if (ai->regs->elr & 1)
340 		ai->regs->spsr |= CPSR_T;
341 	else
342 		ai->regs->spsr &= ~CPSR_T;
343 }
344 #endif /*ARM32*/
345 
346 #ifdef ARM64
347 static void handle_user_ta_panic(struct abort_info *ai)
348 {
349 	uint32_t daif;
350 
351 	/*
352 	 * It was a user exception, stop user execution and return
353 	 * to TEE Core.
354 	 */
355 	ai->regs->x0 = TEE_ERROR_TARGET_DEAD;
356 	ai->regs->x1 = true;
357 	ai->regs->x2 = 0xdeadbeef;
358 	ai->regs->elr = (vaddr_t)thread_unwind_user_mode;
359 	ai->regs->sp_el0 = thread_get_saved_thread_sp();
360 
361 	daif = (ai->regs->spsr >> SPSR_32_AIF_SHIFT) & SPSR_32_AIF_MASK;
362 	/* XXX what about DAIF_D? */
363 	ai->regs->spsr = SPSR_64(SPSR_64_MODE_EL1, SPSR_64_MODE_SP_EL0, daif);
364 }
365 #endif /*ARM64*/
366 
367 #ifdef CFG_WITH_VFP
368 static void handle_user_ta_vfp(void)
369 {
370 	struct tee_ta_session *s;
371 
372 	if (tee_ta_get_current_session(&s) != TEE_SUCCESS)
373 		panic();
374 
375 	thread_user_enable_vfp(&to_user_mode_ctx(s->ctx)->vfp);
376 }
377 #endif /*CFG_WITH_VFP*/
378 
379 #ifdef CFG_WITH_USER_TA
380 #ifdef ARM32
381 /* Returns true if the exception originated from user mode */
382 bool abort_is_user_exception(struct abort_info *ai)
383 {
384 	return (ai->regs->spsr & ARM32_CPSR_MODE_MASK) == ARM32_CPSR_MODE_USR;
385 }
386 #endif /*ARM32*/
387 
388 #ifdef ARM64
389 /* Returns true if the exception originated from user mode */
390 bool abort_is_user_exception(struct abort_info *ai)
391 {
392 	uint32_t spsr = ai->regs->spsr;
393 
394 	if (spsr & (SPSR_MODE_RW_32 << SPSR_MODE_RW_SHIFT))
395 		return true;
396 	if (((spsr >> SPSR_64_MODE_EL_SHIFT) & SPSR_64_MODE_EL_MASK) ==
397 	    SPSR_64_MODE_EL0)
398 		return true;
399 	return false;
400 }
401 #endif /*ARM64*/
402 #else /*CFG_WITH_USER_TA*/
403 bool abort_is_user_exception(struct abort_info *ai __unused)
404 {
405 	return false;
406 }
407 #endif /*CFG_WITH_USER_TA*/
408 
409 #if defined(CFG_WITH_VFP) && defined(CFG_WITH_USER_TA)
410 #ifdef ARM32
411 static bool is_vfp_fault(struct abort_info *ai)
412 {
413 	if ((ai->abort_type != ABORT_TYPE_UNDEF) || vfp_is_enabled())
414 		return false;
415 
416 	/*
417 	 * Not entirely accurate, but if it's a truly undefined instruction
418 	 * we'll end up in this function again, except this time
419 	 * vfp_is_enabled() so we'll return false.
420 	 */
421 	return true;
422 }
423 #endif /*ARM32*/
424 
425 #ifdef ARM64
426 static bool is_vfp_fault(struct abort_info *ai)
427 {
428 	switch ((ai->fault_descr >> ESR_EC_SHIFT) & ESR_EC_MASK) {
429 	case ESR_EC_FP_ASIMD:
430 	case ESR_EC_AARCH32_FP:
431 	case ESR_EC_AARCH64_FP:
432 		return true;
433 	default:
434 		return false;
435 	}
436 }
437 #endif /*ARM64*/
438 #else /*CFG_WITH_VFP && CFG_WITH_USER_TA*/
439 static bool is_vfp_fault(struct abort_info *ai __unused)
440 {
441 	return false;
442 }
443 #endif  /*CFG_WITH_VFP && CFG_WITH_USER_TA*/
444 
445 static enum fault_type get_fault_type(struct abort_info *ai)
446 {
447 	if (abort_is_user_exception(ai)) {
448 		if (is_vfp_fault(ai))
449 			return FAULT_TYPE_USER_TA_VFP;
450 #ifndef CFG_WITH_PAGER
451 		return FAULT_TYPE_USER_TA_PANIC;
452 #endif
453 	}
454 
455 	if (thread_is_from_abort_mode()) {
456 		abort_print_error(ai);
457 		panic("[abort] abort in abort handler (trap CPU)");
458 	}
459 
460 	if (ai->abort_type == ABORT_TYPE_UNDEF) {
461 		if (abort_is_user_exception(ai))
462 			return FAULT_TYPE_USER_TA_PANIC;
463 		abort_print_error(ai);
464 		panic("[abort] undefined abort (trap CPU)");
465 	}
466 
467 	switch (core_mmu_get_fault_type(ai->fault_descr)) {
468 	case CORE_MMU_FAULT_ALIGNMENT:
469 		if (abort_is_user_exception(ai))
470 			return FAULT_TYPE_USER_TA_PANIC;
471 		abort_print_error(ai);
472 		panic("[abort] alignement fault!  (trap CPU)");
473 		break;
474 
475 	case CORE_MMU_FAULT_ACCESS_BIT:
476 		if (abort_is_user_exception(ai))
477 			return FAULT_TYPE_USER_TA_PANIC;
478 		abort_print_error(ai);
479 		panic("[abort] access bit fault!  (trap CPU)");
480 		break;
481 
482 	case CORE_MMU_FAULT_DEBUG_EVENT:
483 		if (!abort_is_user_exception(ai))
484 			abort_print(ai);
485 		DMSG("[abort] Ignoring debug event!");
486 		return FAULT_TYPE_IGNORE;
487 
488 	case CORE_MMU_FAULT_TRANSLATION:
489 	case CORE_MMU_FAULT_WRITE_PERMISSION:
490 	case CORE_MMU_FAULT_READ_PERMISSION:
491 		return FAULT_TYPE_PAGEABLE;
492 
493 	case CORE_MMU_FAULT_ASYNC_EXTERNAL:
494 		if (!abort_is_user_exception(ai))
495 			abort_print(ai);
496 		DMSG("[abort] Ignoring async external abort!");
497 		return FAULT_TYPE_IGNORE;
498 
499 	case CORE_MMU_FAULT_OTHER:
500 	default:
501 		if (!abort_is_user_exception(ai))
502 			abort_print(ai);
503 		DMSG("[abort] Unhandled fault!");
504 		return FAULT_TYPE_IGNORE;
505 	}
506 }
507 
508 void abort_handler(uint32_t abort_type, struct thread_abort_regs *regs)
509 {
510 	struct abort_info ai;
511 	bool handled;
512 
513 	set_abort_info(abort_type, regs, &ai);
514 
515 	switch (get_fault_type(&ai)) {
516 	case FAULT_TYPE_IGNORE:
517 		break;
518 	case FAULT_TYPE_USER_TA_PANIC:
519 		DMSG("[abort] abort in User mode (TA will panic)");
520 		save_abort_info_in_tsd(&ai);
521 		vfp_disable();
522 		handle_user_ta_panic(&ai);
523 		break;
524 #ifdef CFG_WITH_VFP
525 	case FAULT_TYPE_USER_TA_VFP:
526 		handle_user_ta_vfp();
527 		break;
528 #endif
529 	case FAULT_TYPE_PAGEABLE:
530 	default:
531 		if (thread_get_id_may_fail() < 0) {
532 			abort_print_error(&ai);
533 			panic("abort outside thread context");
534 		}
535 		thread_kernel_save_vfp();
536 		handled = tee_pager_handle_fault(&ai);
537 		thread_kernel_restore_vfp();
538 		if (!handled) {
539 			if (!abort_is_user_exception(&ai)) {
540 				abort_print_error(&ai);
541 				panic("unhandled pageable abort");
542 			}
543 			DMSG("[abort] abort in User mode (TA will panic)");
544 			save_abort_info_in_tsd(&ai);
545 			vfp_disable();
546 			handle_user_ta_panic(&ai);
547 		}
548 		break;
549 	}
550 }
551