xref: /optee_os/core/arch/arm/kernel/abort.c (revision 5b25c76ac40f830867e3d60800120ffd7874e8dc)
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/linker.h>
9 #include <kernel/misc.h>
10 #include <kernel/panic.h>
11 #include <kernel/tee_ta_manager.h>
12 #include <kernel/unwind.h>
13 #include <kernel/user_mode_ctx.h>
14 #include <mm/core_mmu.h>
15 #include <mm/mobj.h>
16 #include <mm/tee_pager.h>
17 #include <tee/tee_svc.h>
18 #include <trace.h>
19 
20 #include "thread_private.h"
21 
22 enum fault_type {
23 	FAULT_TYPE_USER_TA_PANIC,
24 	FAULT_TYPE_USER_TA_VFP,
25 	FAULT_TYPE_PAGEABLE,
26 	FAULT_TYPE_IGNORE,
27 };
28 
29 #ifdef CFG_UNWIND
30 
31 #ifdef ARM32
32 /*
33  * Kernel or user mode unwind (32-bit execution state).
34  */
35 static void __print_stack_unwind(struct abort_info *ai)
36 {
37 	struct unwind_state_arm32 state = { };
38 	vaddr_t exidx = (vaddr_t)__exidx_start;
39 	size_t exidx_sz = (vaddr_t)__exidx_end - (vaddr_t)__exidx_start;
40 	uint32_t mode = ai->regs->spsr & CPSR_MODE_MASK;
41 	uint32_t sp = 0;
42 	uint32_t lr = 0;
43 
44 	assert(!abort_is_user_exception(ai));
45 
46 	if (mode == CPSR_MODE_SYS) {
47 		sp = ai->regs->usr_sp;
48 		lr = ai->regs->usr_lr;
49 	} else {
50 		sp = read_mode_sp(mode);
51 		lr = read_mode_lr(mode);
52 	}
53 
54 	memset(&state, 0, sizeof(state));
55 	state.registers[0] = ai->regs->r0;
56 	state.registers[1] = ai->regs->r1;
57 	state.registers[2] = ai->regs->r2;
58 	state.registers[3] = ai->regs->r3;
59 	state.registers[4] = ai->regs->r4;
60 	state.registers[5] = ai->regs->r5;
61 	state.registers[6] = ai->regs->r6;
62 	state.registers[7] = ai->regs->r7;
63 	state.registers[8] = ai->regs->r8;
64 	state.registers[9] = ai->regs->r9;
65 	state.registers[10] = ai->regs->r10;
66 	state.registers[11] = ai->regs->r11;
67 	state.registers[13] = sp;
68 	state.registers[14] = lr;
69 	state.registers[15] = ai->pc;
70 
71 	print_stack_arm32(TRACE_ERROR, &state, exidx, exidx_sz,
72 			  thread_stack_start(), thread_stack_size());
73 }
74 #endif /* ARM32 */
75 
76 #ifdef ARM64
77 /* Kernel mode unwind (64-bit execution state) */
78 static void __print_stack_unwind(struct abort_info *ai)
79 {
80 	struct unwind_state_arm64 state = {
81 		.pc = ai->regs->elr,
82 		.fp = ai->regs->x29,
83 	};
84 
85 	print_stack_arm64(TRACE_ERROR, &state, thread_stack_start(),
86 			  thread_stack_size());
87 }
88 #endif /*ARM64*/
89 
90 #else /* CFG_UNWIND */
91 static void __print_stack_unwind(struct abort_info *ai __unused)
92 {
93 }
94 #endif /* CFG_UNWIND */
95 
96 static __maybe_unused const char *abort_type_to_str(uint32_t abort_type)
97 {
98 	if (abort_type == ABORT_TYPE_DATA)
99 		return "data";
100 	if (abort_type == ABORT_TYPE_PREFETCH)
101 		return "prefetch";
102 	return "undef";
103 }
104 
105 static __maybe_unused const char *fault_to_str(uint32_t abort_type,
106 			uint32_t fault_descr)
107 {
108 	/* fault_descr is only valid for data or prefetch abort */
109 	if (abort_type != ABORT_TYPE_DATA && abort_type != ABORT_TYPE_PREFETCH)
110 		return "";
111 
112 	switch (core_mmu_get_fault_type(fault_descr)) {
113 	case CORE_MMU_FAULT_ALIGNMENT:
114 		return " (alignment fault)";
115 	case CORE_MMU_FAULT_TRANSLATION:
116 		return " (translation fault)";
117 	case CORE_MMU_FAULT_READ_PERMISSION:
118 		return " (read permission fault)";
119 	case CORE_MMU_FAULT_WRITE_PERMISSION:
120 		return " (write permission fault)";
121 	default:
122 		return "";
123 	}
124 }
125 
126 static __maybe_unused void
127 __print_abort_info(struct abort_info *ai __maybe_unused,
128 		   const char *ctx __maybe_unused)
129 {
130 	__maybe_unused size_t core_pos = 0;
131 #ifdef ARM32
132 	uint32_t mode = ai->regs->spsr & CPSR_MODE_MASK;
133 	__maybe_unused uint32_t sp = 0;
134 	__maybe_unused uint32_t lr = 0;
135 
136 	if (mode == CPSR_MODE_USR || mode == CPSR_MODE_SYS) {
137 		sp = ai->regs->usr_sp;
138 		lr = ai->regs->usr_lr;
139 		core_pos = thread_get_tsd()->abort_core;
140 	} else {
141 		sp = read_mode_sp(mode);
142 		lr = read_mode_lr(mode);
143 		core_pos = get_core_pos();
144 	}
145 #endif /*ARM32*/
146 #ifdef ARM64
147 	if (abort_is_user_exception(ai))
148 		core_pos = thread_get_tsd()->abort_core;
149 	else
150 		core_pos = get_core_pos();
151 #endif /*ARM64*/
152 
153 	EMSG_RAW("");
154 	EMSG_RAW("%s %s-abort at address 0x%" PRIxVA "%s",
155 		ctx, abort_type_to_str(ai->abort_type), ai->va,
156 		fault_to_str(ai->abort_type, ai->fault_descr));
157 #ifdef ARM32
158 	EMSG_RAW(" fsr 0x%08x  ttbr0 0x%08x  ttbr1 0x%08x  cidr 0x%X",
159 		 ai->fault_descr, read_ttbr0(), read_ttbr1(),
160 		 read_contextidr());
161 	EMSG_RAW(" cpu #%zu          cpsr 0x%08x",
162 		 core_pos, ai->regs->spsr);
163 	EMSG_RAW(" r0 0x%08x      r4 0x%08x    r8 0x%08x   r12 0x%08x",
164 		 ai->regs->r0, ai->regs->r4, ai->regs->r8, ai->regs->ip);
165 	EMSG_RAW(" r1 0x%08x      r5 0x%08x    r9 0x%08x    sp 0x%08x",
166 		 ai->regs->r1, ai->regs->r5, ai->regs->r9, sp);
167 	EMSG_RAW(" r2 0x%08x      r6 0x%08x   r10 0x%08x    lr 0x%08x",
168 		 ai->regs->r2, ai->regs->r6, ai->regs->r10, lr);
169 	EMSG_RAW(" r3 0x%08x      r7 0x%08x   r11 0x%08x    pc 0x%08x",
170 		 ai->regs->r3, ai->regs->r7, ai->regs->r11, ai->pc);
171 #endif /*ARM32*/
172 #ifdef ARM64
173 	EMSG_RAW(" esr 0x%08x  ttbr0 0x%08" PRIx64 "   ttbr1 0x%08" PRIx64
174 		 "   cidr 0x%X", ai->fault_descr, read_ttbr0_el1(),
175 		 read_ttbr1_el1(), read_contextidr_el1());
176 	EMSG_RAW(" cpu #%zu          cpsr 0x%08x",
177 		 core_pos, (uint32_t)ai->regs->spsr);
178 	EMSG_RAW(" x0  %016" PRIx64 " x1  %016" PRIx64,
179 		 ai->regs->x0, ai->regs->x1);
180 	EMSG_RAW(" x2  %016" PRIx64 " x3  %016" PRIx64,
181 		 ai->regs->x2, ai->regs->x3);
182 	EMSG_RAW(" x4  %016" PRIx64 " x5  %016" PRIx64,
183 		 ai->regs->x4, ai->regs->x5);
184 	EMSG_RAW(" x6  %016" PRIx64 " x7  %016" PRIx64,
185 		 ai->regs->x6, ai->regs->x7);
186 	EMSG_RAW(" x8  %016" PRIx64 " x9  %016" PRIx64,
187 		 ai->regs->x8, ai->regs->x9);
188 	EMSG_RAW(" x10 %016" PRIx64 " x11 %016" PRIx64,
189 		 ai->regs->x10, ai->regs->x11);
190 	EMSG_RAW(" x12 %016" PRIx64 " x13 %016" PRIx64,
191 		 ai->regs->x12, ai->regs->x13);
192 	EMSG_RAW(" x14 %016" PRIx64 " x15 %016" PRIx64,
193 		 ai->regs->x14, ai->regs->x15);
194 	EMSG_RAW(" x16 %016" PRIx64 " x17 %016" PRIx64,
195 		 ai->regs->x16, ai->regs->x17);
196 	EMSG_RAW(" x18 %016" PRIx64 " x19 %016" PRIx64,
197 		 ai->regs->x18, ai->regs->x19);
198 	EMSG_RAW(" x20 %016" PRIx64 " x21 %016" PRIx64,
199 		 ai->regs->x20, ai->regs->x21);
200 	EMSG_RAW(" x22 %016" PRIx64 " x23 %016" PRIx64,
201 		 ai->regs->x22, ai->regs->x23);
202 	EMSG_RAW(" x24 %016" PRIx64 " x25 %016" PRIx64,
203 		 ai->regs->x24, ai->regs->x25);
204 	EMSG_RAW(" x26 %016" PRIx64 " x27 %016" PRIx64,
205 		 ai->regs->x26, ai->regs->x27);
206 	EMSG_RAW(" x28 %016" PRIx64 " x29 %016" PRIx64,
207 		 ai->regs->x28, ai->regs->x29);
208 	EMSG_RAW(" x30 %016" PRIx64 " elr %016" PRIx64,
209 		 ai->regs->x30, ai->regs->elr);
210 	EMSG_RAW(" sp_el0 %016" PRIx64, ai->regs->sp_el0);
211 #endif /*ARM64*/
212 }
213 
214 /*
215  * Print abort info and (optionally) stack dump to the console
216  * @ai kernel-mode abort info.
217  * @stack_dump true to show a stack trace
218  */
219 static void __abort_print(struct abort_info *ai, bool stack_dump)
220 {
221 	assert(!abort_is_user_exception(ai));
222 
223 	__print_abort_info(ai, "Core");
224 
225 	if (stack_dump)
226 		__print_stack_unwind(ai);
227 }
228 
229 void abort_print(struct abort_info *ai)
230 {
231 	__abort_print(ai, false);
232 }
233 
234 void abort_print_error(struct abort_info *ai)
235 {
236 	__abort_print(ai, true);
237 }
238 
239 /* This function must be called from a normal thread */
240 void abort_print_current_ta(void)
241 {
242 	struct thread_specific_data *tsd = thread_get_tsd();
243 	struct abort_info ai = { };
244 	struct tee_ta_session *s = NULL;
245 
246 	if (tee_ta_get_current_session(&s) != TEE_SUCCESS)
247 		panic();
248 
249 	ai.abort_type = tsd->abort_type;
250 	ai.fault_descr = tsd->abort_descr;
251 	ai.va = tsd->abort_va;
252 	ai.pc = tsd->abort_regs.elr;
253 	ai.regs = &tsd->abort_regs;
254 
255 	if (ai.abort_type != ABORT_TYPE_TA_PANIC)
256 		__print_abort_info(&ai, "User TA");
257 
258 	s->ctx->ops->dump_state(s->ctx);
259 
260 #if defined(CFG_FTRACE_SUPPORT)
261 	if (s->ctx->ops->dump_ftrace) {
262 		s->fbuf = NULL;
263 		s->ctx->ops->dump_ftrace(s->ctx);
264 	}
265 #endif
266 }
267 
268 static void save_abort_info_in_tsd(struct abort_info *ai)
269 {
270 	struct thread_specific_data *tsd = thread_get_tsd();
271 
272 	tsd->abort_type = ai->abort_type;
273 	tsd->abort_descr = ai->fault_descr;
274 	tsd->abort_va = ai->va;
275 	tsd->abort_regs = *ai->regs;
276 	tsd->abort_core = get_core_pos();
277 }
278 
279 #ifdef ARM32
280 static void set_abort_info(uint32_t abort_type, struct thread_abort_regs *regs,
281 		struct abort_info *ai)
282 {
283 	switch (abort_type) {
284 	case ABORT_TYPE_DATA:
285 		ai->fault_descr = read_dfsr();
286 		ai->va = read_dfar();
287 		break;
288 	case ABORT_TYPE_PREFETCH:
289 		ai->fault_descr = read_ifsr();
290 		ai->va = read_ifar();
291 		break;
292 	default:
293 		ai->fault_descr = 0;
294 		ai->va = regs->elr;
295 		break;
296 	}
297 	ai->abort_type = abort_type;
298 	ai->pc = regs->elr;
299 	ai->regs = regs;
300 }
301 #endif /*ARM32*/
302 
303 #ifdef ARM64
304 static void set_abort_info(uint32_t abort_type __unused,
305 		struct thread_abort_regs *regs, struct abort_info *ai)
306 {
307 	ai->fault_descr = read_esr_el1();
308 	switch ((ai->fault_descr >> ESR_EC_SHIFT) & ESR_EC_MASK) {
309 	case ESR_EC_IABT_EL0:
310 	case ESR_EC_IABT_EL1:
311 		ai->abort_type = ABORT_TYPE_PREFETCH;
312 		ai->va = read_far_el1();
313 		break;
314 	case ESR_EC_DABT_EL0:
315 	case ESR_EC_DABT_EL1:
316 	case ESR_EC_SP_ALIGN:
317 		ai->abort_type = ABORT_TYPE_DATA;
318 		ai->va = read_far_el1();
319 		break;
320 	default:
321 		ai->abort_type = ABORT_TYPE_UNDEF;
322 		ai->va = regs->elr;
323 	}
324 	ai->pc = regs->elr;
325 	ai->regs = regs;
326 }
327 #endif /*ARM64*/
328 
329 #ifdef ARM32
330 static void handle_user_ta_panic(struct abort_info *ai)
331 {
332 	/*
333 	 * It was a user exception, stop user execution and return
334 	 * to TEE Core.
335 	 */
336 	ai->regs->r0 = TEE_ERROR_TARGET_DEAD;
337 	ai->regs->r1 = true;
338 	ai->regs->r2 = 0xdeadbeef;
339 	ai->regs->elr = (uint32_t)thread_unwind_user_mode;
340 	ai->regs->spsr &= CPSR_FIA;
341 	ai->regs->spsr &= ~CPSR_MODE_MASK;
342 	ai->regs->spsr |= CPSR_MODE_SVC;
343 	/* Select Thumb or ARM mode */
344 	if (ai->regs->elr & 1)
345 		ai->regs->spsr |= CPSR_T;
346 	else
347 		ai->regs->spsr &= ~CPSR_T;
348 }
349 #endif /*ARM32*/
350 
351 #ifdef ARM64
352 static void handle_user_ta_panic(struct abort_info *ai)
353 {
354 	uint32_t daif;
355 
356 	/*
357 	 * It was a user exception, stop user execution and return
358 	 * to TEE Core.
359 	 */
360 	ai->regs->x0 = TEE_ERROR_TARGET_DEAD;
361 	ai->regs->x1 = true;
362 	ai->regs->x2 = 0xdeadbeef;
363 	ai->regs->elr = (vaddr_t)thread_unwind_user_mode;
364 	ai->regs->sp_el0 = thread_get_saved_thread_sp();
365 
366 	daif = (ai->regs->spsr >> SPSR_32_AIF_SHIFT) & SPSR_32_AIF_MASK;
367 	/* XXX what about DAIF_D? */
368 	ai->regs->spsr = SPSR_64(SPSR_64_MODE_EL1, SPSR_64_MODE_SP_EL0, daif);
369 }
370 #endif /*ARM64*/
371 
372 #ifdef CFG_WITH_VFP
373 static void handle_user_ta_vfp(void)
374 {
375 	struct tee_ta_session *s;
376 
377 	if (tee_ta_get_current_session(&s) != TEE_SUCCESS)
378 		panic();
379 
380 	thread_user_enable_vfp(&to_user_mode_ctx(s->ctx)->vfp);
381 }
382 #endif /*CFG_WITH_VFP*/
383 
384 #ifdef CFG_WITH_USER_TA
385 #ifdef ARM32
386 /* Returns true if the exception originated from user mode */
387 bool abort_is_user_exception(struct abort_info *ai)
388 {
389 	return (ai->regs->spsr & ARM32_CPSR_MODE_MASK) == ARM32_CPSR_MODE_USR;
390 }
391 #endif /*ARM32*/
392 
393 #ifdef ARM64
394 /* Returns true if the exception originated from user mode */
395 bool abort_is_user_exception(struct abort_info *ai)
396 {
397 	uint32_t spsr = ai->regs->spsr;
398 
399 	if (spsr & (SPSR_MODE_RW_32 << SPSR_MODE_RW_SHIFT))
400 		return true;
401 	if (((spsr >> SPSR_64_MODE_EL_SHIFT) & SPSR_64_MODE_EL_MASK) ==
402 	    SPSR_64_MODE_EL0)
403 		return true;
404 	return false;
405 }
406 #endif /*ARM64*/
407 #else /*CFG_WITH_USER_TA*/
408 bool abort_is_user_exception(struct abort_info *ai __unused)
409 {
410 	return false;
411 }
412 #endif /*CFG_WITH_USER_TA*/
413 
414 #if defined(CFG_WITH_VFP) && defined(CFG_WITH_USER_TA)
415 #ifdef ARM32
416 static bool is_vfp_fault(struct abort_info *ai)
417 {
418 	if ((ai->abort_type != ABORT_TYPE_UNDEF) || vfp_is_enabled())
419 		return false;
420 
421 	/*
422 	 * Not entirely accurate, but if it's a truly undefined instruction
423 	 * we'll end up in this function again, except this time
424 	 * vfp_is_enabled() so we'll return false.
425 	 */
426 	return true;
427 }
428 #endif /*ARM32*/
429 
430 #ifdef ARM64
431 static bool is_vfp_fault(struct abort_info *ai)
432 {
433 	switch ((ai->fault_descr >> ESR_EC_SHIFT) & ESR_EC_MASK) {
434 	case ESR_EC_FP_ASIMD:
435 	case ESR_EC_AARCH32_FP:
436 	case ESR_EC_AARCH64_FP:
437 		return true;
438 	default:
439 		return false;
440 	}
441 }
442 #endif /*ARM64*/
443 #else /*CFG_WITH_VFP && CFG_WITH_USER_TA*/
444 static bool is_vfp_fault(struct abort_info *ai __unused)
445 {
446 	return false;
447 }
448 #endif  /*CFG_WITH_VFP && CFG_WITH_USER_TA*/
449 
450 static enum fault_type get_fault_type(struct abort_info *ai)
451 {
452 	if (abort_is_user_exception(ai)) {
453 		if (is_vfp_fault(ai))
454 			return FAULT_TYPE_USER_TA_VFP;
455 #ifndef CFG_WITH_PAGER
456 		return FAULT_TYPE_USER_TA_PANIC;
457 #endif
458 	}
459 
460 	if (thread_is_from_abort_mode()) {
461 		abort_print_error(ai);
462 		panic("[abort] abort in abort handler (trap CPU)");
463 	}
464 
465 	if (ai->abort_type == ABORT_TYPE_UNDEF) {
466 		if (abort_is_user_exception(ai))
467 			return FAULT_TYPE_USER_TA_PANIC;
468 		abort_print_error(ai);
469 		panic("[abort] undefined abort (trap CPU)");
470 	}
471 
472 	switch (core_mmu_get_fault_type(ai->fault_descr)) {
473 	case CORE_MMU_FAULT_ALIGNMENT:
474 		if (abort_is_user_exception(ai))
475 			return FAULT_TYPE_USER_TA_PANIC;
476 		abort_print_error(ai);
477 		panic("[abort] alignement fault!  (trap CPU)");
478 		break;
479 
480 	case CORE_MMU_FAULT_ACCESS_BIT:
481 		if (abort_is_user_exception(ai))
482 			return FAULT_TYPE_USER_TA_PANIC;
483 		abort_print_error(ai);
484 		panic("[abort] access bit fault!  (trap CPU)");
485 		break;
486 
487 	case CORE_MMU_FAULT_DEBUG_EVENT:
488 		if (!abort_is_user_exception(ai))
489 			abort_print(ai);
490 		DMSG("[abort] Ignoring debug event!");
491 		return FAULT_TYPE_IGNORE;
492 
493 	case CORE_MMU_FAULT_TRANSLATION:
494 	case CORE_MMU_FAULT_WRITE_PERMISSION:
495 	case CORE_MMU_FAULT_READ_PERMISSION:
496 		return FAULT_TYPE_PAGEABLE;
497 
498 	case CORE_MMU_FAULT_ASYNC_EXTERNAL:
499 		if (!abort_is_user_exception(ai))
500 			abort_print(ai);
501 		DMSG("[abort] Ignoring async external abort!");
502 		return FAULT_TYPE_IGNORE;
503 
504 	case CORE_MMU_FAULT_OTHER:
505 	default:
506 		if (!abort_is_user_exception(ai))
507 			abort_print(ai);
508 		DMSG("[abort] Unhandled fault!");
509 		return FAULT_TYPE_IGNORE;
510 	}
511 }
512 
513 void abort_handler(uint32_t abort_type, struct thread_abort_regs *regs)
514 {
515 	struct abort_info ai;
516 	bool handled;
517 
518 	set_abort_info(abort_type, regs, &ai);
519 
520 	switch (get_fault_type(&ai)) {
521 	case FAULT_TYPE_IGNORE:
522 		break;
523 	case FAULT_TYPE_USER_TA_PANIC:
524 		DMSG("[abort] abort in User mode (TA will panic)");
525 		save_abort_info_in_tsd(&ai);
526 		vfp_disable();
527 		handle_user_ta_panic(&ai);
528 		break;
529 #ifdef CFG_WITH_VFP
530 	case FAULT_TYPE_USER_TA_VFP:
531 		handle_user_ta_vfp();
532 		break;
533 #endif
534 	case FAULT_TYPE_PAGEABLE:
535 	default:
536 		if (thread_get_id_may_fail() < 0) {
537 			abort_print_error(&ai);
538 			panic("abort outside thread context");
539 		}
540 		thread_kernel_save_vfp();
541 		handled = tee_pager_handle_fault(&ai);
542 		thread_kernel_restore_vfp();
543 		if (!handled) {
544 			if (!abort_is_user_exception(&ai)) {
545 				abort_print_error(&ai);
546 				panic("unhandled pageable abort");
547 			}
548 			DMSG("[abort] abort in User mode (TA will panic)");
549 			save_abort_info_in_tsd(&ai);
550 			vfp_disable();
551 			handle_user_ta_panic(&ai);
552 		}
553 		break;
554 	}
555 }
556