1 /*- 2 * Copyright (c) 2014 Andrew Turner 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 */ 27 28 #include "opt_ddb.h" 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/asan.h> 36 #include <sys/kernel.h> 37 #include <sys/ktr.h> 38 #include <sys/lock.h> 39 #include <sys/mutex.h> 40 #include <sys/proc.h> 41 #include <sys/ptrace.h> 42 #include <sys/syscall.h> 43 #include <sys/sysent.h> 44 #ifdef KDB 45 #include <sys/kdb.h> 46 #endif 47 48 #include <vm/vm.h> 49 #include <vm/pmap.h> 50 #include <vm/vm_kern.h> 51 #include <vm/vm_map.h> 52 #include <vm/vm_param.h> 53 #include <vm/vm_extern.h> 54 55 #include <machine/frame.h> 56 #include <machine/md_var.h> 57 #include <machine/pcb.h> 58 #include <machine/pcpu.h> 59 #include <machine/undefined.h> 60 61 #ifdef KDTRACE_HOOKS 62 #include <sys/dtrace_bsd.h> 63 #endif 64 65 #ifdef VFP 66 #include <machine/vfp.h> 67 #endif 68 69 #ifdef KDB 70 #include <machine/db_machdep.h> 71 #endif 72 73 #ifdef DDB 74 #include <ddb/ddb.h> 75 #include <ddb/db_sym.h> 76 #endif 77 78 /* Called from exception.S */ 79 void do_el1h_sync(struct thread *, struct trapframe *); 80 void do_el0_sync(struct thread *, struct trapframe *); 81 void do_el0_error(struct trapframe *); 82 void do_serror(struct trapframe *); 83 void unhandled_exception(struct trapframe *); 84 85 static void print_gp_register(const char *name, uint64_t value); 86 static void print_registers(struct trapframe *frame); 87 88 int (*dtrace_invop_jump_addr)(struct trapframe *); 89 90 typedef void (abort_handler)(struct thread *, struct trapframe *, uint64_t, 91 uint64_t, int); 92 93 static abort_handler align_abort; 94 static abort_handler data_abort; 95 static abort_handler external_abort; 96 97 static abort_handler *abort_handlers[] = { 98 [ISS_DATA_DFSC_TF_L0] = data_abort, 99 [ISS_DATA_DFSC_TF_L1] = data_abort, 100 [ISS_DATA_DFSC_TF_L2] = data_abort, 101 [ISS_DATA_DFSC_TF_L3] = data_abort, 102 [ISS_DATA_DFSC_AFF_L1] = data_abort, 103 [ISS_DATA_DFSC_AFF_L2] = data_abort, 104 [ISS_DATA_DFSC_AFF_L3] = data_abort, 105 [ISS_DATA_DFSC_PF_L1] = data_abort, 106 [ISS_DATA_DFSC_PF_L2] = data_abort, 107 [ISS_DATA_DFSC_PF_L3] = data_abort, 108 [ISS_DATA_DFSC_ALIGN] = align_abort, 109 [ISS_DATA_DFSC_EXT] = external_abort, 110 [ISS_DATA_DFSC_EXT_L0] = external_abort, 111 [ISS_DATA_DFSC_EXT_L1] = external_abort, 112 [ISS_DATA_DFSC_EXT_L2] = external_abort, 113 [ISS_DATA_DFSC_EXT_L3] = external_abort, 114 [ISS_DATA_DFSC_ECC] = external_abort, 115 [ISS_DATA_DFSC_ECC_L0] = external_abort, 116 [ISS_DATA_DFSC_ECC_L1] = external_abort, 117 [ISS_DATA_DFSC_ECC_L2] = external_abort, 118 [ISS_DATA_DFSC_ECC_L3] = external_abort, 119 }; 120 121 static __inline void 122 call_trapsignal(struct thread *td, int sig, int code, void *addr, int trapno) 123 { 124 ksiginfo_t ksi; 125 126 ksiginfo_init_trap(&ksi); 127 ksi.ksi_signo = sig; 128 ksi.ksi_code = code; 129 ksi.ksi_addr = addr; 130 ksi.ksi_trapno = trapno; 131 trapsignal(td, &ksi); 132 } 133 134 int 135 cpu_fetch_syscall_args(struct thread *td) 136 { 137 struct proc *p; 138 syscallarg_t *ap, *dst_ap; 139 struct syscall_args *sa; 140 141 p = td->td_proc; 142 sa = &td->td_sa; 143 ap = td->td_frame->tf_x; 144 dst_ap = &sa->args[0]; 145 146 sa->code = td->td_frame->tf_x[8]; 147 sa->original_code = sa->code; 148 149 if (__predict_false(sa->code == SYS_syscall || sa->code == SYS___syscall)) { 150 sa->code = *ap++; 151 } else { 152 *dst_ap++ = *ap++; 153 } 154 155 if (__predict_false(sa->code >= p->p_sysent->sv_size)) 156 sa->callp = &p->p_sysent->sv_table[0]; 157 else 158 sa->callp = &p->p_sysent->sv_table[sa->code]; 159 160 KASSERT(sa->callp->sy_narg <= nitems(sa->args), 161 ("Syscall %d takes too many arguments", sa->code)); 162 163 memcpy(dst_ap, ap, (nitems(sa->args) - 1) * sizeof(*dst_ap)); 164 165 td->td_retval[0] = 0; 166 td->td_retval[1] = 0; 167 168 return (0); 169 } 170 171 #include "../../kern/subr_syscall.c" 172 173 /* 174 * Test for fault generated by given access instruction in 175 * bus_peek_<foo> or bus_poke_<foo> bus function. 176 */ 177 extern uint32_t generic_bs_peek_1f, generic_bs_peek_2f; 178 extern uint32_t generic_bs_peek_4f, generic_bs_peek_8f; 179 extern uint32_t generic_bs_poke_1f, generic_bs_poke_2f; 180 extern uint32_t generic_bs_poke_4f, generic_bs_poke_8f; 181 182 static bool 183 test_bs_fault(void *addr) 184 { 185 return (addr == &generic_bs_peek_1f || 186 addr == &generic_bs_peek_2f || 187 addr == &generic_bs_peek_4f || 188 addr == &generic_bs_peek_8f || 189 addr == &generic_bs_poke_1f || 190 addr == &generic_bs_poke_2f || 191 addr == &generic_bs_poke_4f || 192 addr == &generic_bs_poke_8f); 193 } 194 195 static void 196 svc_handler(struct thread *td, struct trapframe *frame) 197 { 198 199 if ((frame->tf_esr & ESR_ELx_ISS_MASK) == 0) { 200 syscallenter(td); 201 syscallret(td); 202 } else { 203 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr, 204 ESR_ELx_EXCEPTION(frame->tf_esr)); 205 userret(td, frame); 206 } 207 } 208 209 static void 210 align_abort(struct thread *td, struct trapframe *frame, uint64_t esr, 211 uint64_t far, int lower) 212 { 213 if (!lower) { 214 print_registers(frame); 215 print_gp_register("far", far); 216 printf(" esr: %16lx\n", esr); 217 panic("Misaligned access from kernel space!"); 218 } 219 220 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr, 221 ESR_ELx_EXCEPTION(frame->tf_esr)); 222 userret(td, frame); 223 } 224 225 226 static void 227 external_abort(struct thread *td, struct trapframe *frame, uint64_t esr, 228 uint64_t far, int lower) 229 { 230 231 /* 232 * Try to handle synchronous external aborts caused by 233 * bus_space_peek() and/or bus_space_poke() functions. 234 */ 235 if (!lower && test_bs_fault((void *)frame->tf_elr)) { 236 frame->tf_elr = (uint64_t)generic_bs_fault; 237 return; 238 } 239 240 print_registers(frame); 241 print_gp_register("far", far); 242 panic("Unhandled EL%d external data abort", lower ? 0: 1); 243 } 244 245 /* 246 * It is unsafe to access the stack canary value stored in "td" until 247 * kernel map translation faults are handled, see the pmap_klookup() call below. 248 * Thus, stack-smashing detection with per-thread canaries must be disabled in 249 * this function. 250 */ 251 static void NO_PERTHREAD_SSP 252 data_abort(struct thread *td, struct trapframe *frame, uint64_t esr, 253 uint64_t far, int lower) 254 { 255 struct vm_map *map; 256 struct pcb *pcb; 257 vm_prot_t ftype; 258 int error, sig, ucode; 259 #ifdef KDB 260 bool handled; 261 #endif 262 263 /* 264 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive 265 * and Store-Exclusive instruction usage restrictions", state 266 * of the exclusive monitors after data abort exception is unknown. 267 */ 268 clrex(); 269 270 #ifdef KDB 271 if (kdb_active) { 272 kdb_reenter(); 273 return; 274 } 275 #endif 276 277 if (lower) { 278 map = &td->td_proc->p_vmspace->vm_map; 279 } else if (!ADDR_IS_CANONICAL(far)) { 280 /* We received a TBI/PAC/etc. fault from the kernel */ 281 error = KERN_INVALID_ADDRESS; 282 goto bad_far; 283 } else if (ADDR_IS_KERNEL(far)) { 284 /* 285 * Handle a special case: the data abort was caused by accessing 286 * a thread structure while its mapping was being promoted or 287 * demoted, as a consequence of the break-before-make rule. It 288 * is not safe to enable interrupts or dereference "td" before 289 * this case is handled. 290 * 291 * In principle, if pmap_klookup() fails, there is no need to 292 * call pmap_fault() below, but avoiding that call is not worth 293 * the effort. 294 */ 295 if (ESR_ELx_EXCEPTION(esr) == EXCP_DATA_ABORT) { 296 switch (esr & ISS_DATA_DFSC_MASK) { 297 case ISS_DATA_DFSC_TF_L0: 298 case ISS_DATA_DFSC_TF_L1: 299 case ISS_DATA_DFSC_TF_L2: 300 case ISS_DATA_DFSC_TF_L3: 301 if (pmap_klookup(far, NULL)) 302 return; 303 break; 304 } 305 } 306 intr_enable(); 307 map = kernel_map; 308 } else { 309 intr_enable(); 310 map = &td->td_proc->p_vmspace->vm_map; 311 if (map == NULL) 312 map = kernel_map; 313 } 314 pcb = td->td_pcb; 315 316 /* 317 * Try to handle translation, access flag, and permission faults. 318 * Translation faults may occur as a result of the required 319 * break-before-make sequence used when promoting or demoting 320 * superpages. Such faults must not occur while holding the pmap lock, 321 * or pmap_fault() will recurse on that lock. 322 */ 323 if ((lower || map == kernel_map || pcb->pcb_onfault != 0) && 324 pmap_fault(map->pmap, esr, far) == KERN_SUCCESS) 325 return; 326 327 #ifdef INVARIANTS 328 if (td->td_md.md_spinlock_count != 0) { 329 print_registers(frame); 330 print_gp_register("far", far); 331 printf(" esr: %.16lx\n", esr); 332 panic("data abort with spinlock held"); 333 } 334 #endif 335 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | 336 WARN_GIANTOK, NULL, "Kernel page fault") != 0) { 337 print_registers(frame); 338 print_gp_register("far", far); 339 printf(" esr: %16lx\n", esr); 340 panic("data abort in critical section or under mutex"); 341 } 342 343 switch (ESR_ELx_EXCEPTION(esr)) { 344 case EXCP_INSN_ABORT: 345 case EXCP_INSN_ABORT_L: 346 ftype = VM_PROT_EXECUTE; 347 break; 348 default: 349 /* 350 * If the exception was because of a read or cache operation 351 * pass a read fault type into the vm code. Cache operations 352 * need read permission but will set the WnR flag when the 353 * memory is unmapped. 354 */ 355 if ((esr & ISS_DATA_WnR) == 0 || (esr & ISS_DATA_CM) != 0) 356 ftype = VM_PROT_READ; 357 else 358 ftype = VM_PROT_WRITE; 359 break; 360 } 361 362 /* Fault in the page. */ 363 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode); 364 if (error != KERN_SUCCESS) { 365 if (lower) { 366 call_trapsignal(td, sig, ucode, (void *)far, 367 ESR_ELx_EXCEPTION(esr)); 368 } else { 369 bad_far: 370 if (td->td_intr_nesting_level == 0 && 371 pcb->pcb_onfault != 0) { 372 frame->tf_x[0] = error; 373 frame->tf_elr = pcb->pcb_onfault; 374 return; 375 } 376 377 printf("Fatal data abort:\n"); 378 print_registers(frame); 379 print_gp_register("far", far); 380 printf(" esr: %16lx\n", esr); 381 382 #ifdef KDB 383 if (debugger_on_trap) { 384 kdb_why = KDB_WHY_TRAP; 385 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0, 386 frame); 387 kdb_why = KDB_WHY_UNSET; 388 if (handled) 389 return; 390 } 391 #endif 392 panic("vm_fault failed: %lx error %d", 393 frame->tf_elr, error); 394 } 395 } 396 397 if (lower) 398 userret(td, frame); 399 } 400 401 static void 402 print_gp_register(const char *name, uint64_t value) 403 { 404 #if defined(DDB) 405 c_db_sym_t sym; 406 const char *sym_name; 407 db_expr_t sym_value; 408 db_expr_t offset; 409 #endif 410 411 printf(" %s: %16lx", name, value); 412 #if defined(DDB) 413 /* If this looks like a kernel address try to find the symbol */ 414 if (value >= VM_MIN_KERNEL_ADDRESS) { 415 sym = db_search_symbol(value, DB_STGY_ANY, &offset); 416 if (sym != C_DB_SYM_NULL) { 417 db_symbol_values(sym, &sym_name, &sym_value); 418 printf(" (%s + %lx)", sym_name, offset); 419 } 420 } 421 #endif 422 printf("\n"); 423 } 424 425 static void 426 print_registers(struct trapframe *frame) 427 { 428 char name[4]; 429 u_int reg; 430 431 for (reg = 0; reg < nitems(frame->tf_x); reg++) { 432 snprintf(name, sizeof(name), "%sx%d", (reg < 10) ? " " : "", 433 reg); 434 print_gp_register(name, frame->tf_x[reg]); 435 } 436 printf(" sp: %16lx\n", frame->tf_sp); 437 print_gp_register(" lr", frame->tf_lr); 438 print_gp_register("elr", frame->tf_elr); 439 printf("spsr: %16lx\n", frame->tf_spsr); 440 } 441 442 #ifdef VFP 443 static void 444 fpe_trap(struct thread *td, void *addr, uint32_t exception) 445 { 446 int code; 447 448 code = FPE_FLTIDO; 449 if ((exception & ISS_FP_TFV) != 0) { 450 if ((exception & ISS_FP_IOF) != 0) 451 code = FPE_FLTINV; 452 else if ((exception & ISS_FP_DZF) != 0) 453 code = FPE_FLTDIV; 454 else if ((exception & ISS_FP_OFF) != 0) 455 code = FPE_FLTOVF; 456 else if ((exception & ISS_FP_UFF) != 0) 457 code = FPE_FLTUND; 458 else if ((exception & ISS_FP_IXF) != 0) 459 code = FPE_FLTRES; 460 } 461 call_trapsignal(td, SIGFPE, code, addr, exception); 462 } 463 #endif 464 465 /* 466 * See the comment above data_abort(). 467 */ 468 void NO_PERTHREAD_SSP 469 do_el1h_sync(struct thread *td, struct trapframe *frame) 470 { 471 uint32_t exception; 472 uint64_t esr, far; 473 int dfsc; 474 475 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 476 far = frame->tf_far; 477 /* Read the esr register to get the exception details */ 478 esr = frame->tf_esr; 479 exception = ESR_ELx_EXCEPTION(esr); 480 481 #ifdef KDTRACE_HOOKS 482 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception)) 483 return; 484 #endif 485 486 CTR4(KTR_TRAP, 487 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, 488 esr, frame->tf_elr, frame); 489 490 /* 491 * Enable debug exceptions if we aren't already handling one. They will 492 * be masked again in the exception handler's epilogue. 493 */ 494 if (exception != EXCP_BRK && exception != EXCP_WATCHPT_EL1 && 495 exception != EXCP_SOFTSTP_EL1) 496 dbg_enable(); 497 498 switch (exception) { 499 case EXCP_FP_SIMD: 500 case EXCP_TRAP_FP: 501 #ifdef VFP 502 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) { 503 vfp_restore_state(); 504 } else 505 #endif 506 { 507 print_registers(frame); 508 printf(" esr: %16lx\n", esr); 509 panic("VFP exception in the kernel"); 510 } 511 break; 512 case EXCP_INSN_ABORT: 513 case EXCP_DATA_ABORT: 514 dfsc = esr & ISS_DATA_DFSC_MASK; 515 if (dfsc < nitems(abort_handlers) && 516 abort_handlers[dfsc] != NULL) { 517 abort_handlers[dfsc](td, frame, esr, far, 0); 518 } else { 519 print_registers(frame); 520 print_gp_register("far", far); 521 printf(" esr: %16lx\n", esr); 522 panic("Unhandled EL1 %s abort: %x", 523 exception == EXCP_INSN_ABORT ? "instruction" : 524 "data", dfsc); 525 } 526 break; 527 case EXCP_BRK: 528 #ifdef KDTRACE_HOOKS 529 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \ 530 dtrace_invop_jump_addr != 0) { 531 dtrace_invop_jump_addr(frame); 532 break; 533 } 534 #endif 535 #ifdef KDB 536 kdb_trap(exception, 0, frame); 537 #else 538 panic("No debugger in kernel."); 539 #endif 540 break; 541 case EXCP_WATCHPT_EL1: 542 case EXCP_SOFTSTP_EL1: 543 #ifdef KDB 544 kdb_trap(exception, 0, frame); 545 #else 546 panic("No debugger in kernel."); 547 #endif 548 break; 549 case EXCP_FPAC: 550 /* We can see this if the authentication on PAC fails */ 551 print_registers(frame); 552 print_gp_register("far", far); 553 panic("FPAC kernel exception"); 554 break; 555 case EXCP_UNKNOWN: 556 if (undef_insn(1, frame)) 557 break; 558 print_registers(frame); 559 print_gp_register("far", far); 560 panic("Undefined instruction: %08x", 561 *(uint32_t *)frame->tf_elr); 562 break; 563 default: 564 print_registers(frame); 565 print_gp_register("far", far); 566 panic("Unknown kernel exception %x esr_el1 %lx", exception, 567 esr); 568 } 569 } 570 571 void 572 do_el0_sync(struct thread *td, struct trapframe *frame) 573 { 574 pcpu_bp_harden bp_harden; 575 uint32_t exception; 576 uint64_t esr, far; 577 int dfsc; 578 579 /* Check we have a sane environment when entering from userland */ 580 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS, 581 ("Invalid pcpu address from userland: %p (tpidr %lx)", 582 get_pcpu(), READ_SPECIALREG(tpidr_el1))); 583 584 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 585 far = frame->tf_far; 586 esr = frame->tf_esr; 587 exception = ESR_ELx_EXCEPTION(esr); 588 if (exception == EXCP_INSN_ABORT_L && far > VM_MAXUSER_ADDRESS) { 589 /* 590 * Userspace may be trying to train the branch predictor to 591 * attack the kernel. If we are on a CPU affected by this 592 * call the handler to clear the branch predictor state. 593 */ 594 bp_harden = PCPU_GET(bp_harden); 595 if (bp_harden != NULL) 596 bp_harden(); 597 } 598 intr_enable(); 599 600 CTR4(KTR_TRAP, 601 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr, 602 frame->tf_elr, frame); 603 604 switch (exception) { 605 case EXCP_FP_SIMD: 606 #ifdef VFP 607 vfp_restore_state(); 608 #else 609 panic("VFP exception in userland"); 610 #endif 611 break; 612 case EXCP_TRAP_FP: 613 #ifdef VFP 614 fpe_trap(td, (void *)frame->tf_elr, esr); 615 userret(td, frame); 616 #else 617 panic("VFP exception in userland"); 618 #endif 619 break; 620 case EXCP_SVE: 621 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)frame->tf_elr, 622 exception); 623 userret(td, frame); 624 break; 625 case EXCP_SVC32: 626 case EXCP_SVC64: 627 svc_handler(td, frame); 628 break; 629 case EXCP_INSN_ABORT_L: 630 case EXCP_DATA_ABORT_L: 631 case EXCP_DATA_ABORT: 632 dfsc = esr & ISS_DATA_DFSC_MASK; 633 if (dfsc < nitems(abort_handlers) && 634 abort_handlers[dfsc] != NULL) 635 abort_handlers[dfsc](td, frame, esr, far, 1); 636 else { 637 print_registers(frame); 638 print_gp_register("far", far); 639 printf(" esr: %16lx\n", esr); 640 panic("Unhandled EL0 %s abort: %x", 641 exception == EXCP_INSN_ABORT_L ? "instruction" : 642 "data", dfsc); 643 } 644 break; 645 case EXCP_UNKNOWN: 646 if (!undef_insn(0, frame)) 647 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far, 648 exception); 649 userret(td, frame); 650 break; 651 case EXCP_FPAC: 652 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr, 653 exception); 654 userret(td, frame); 655 break; 656 case EXCP_SP_ALIGN: 657 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp, 658 exception); 659 userret(td, frame); 660 break; 661 case EXCP_PC_ALIGN: 662 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr, 663 exception); 664 userret(td, frame); 665 break; 666 case EXCP_BRKPT_EL0: 667 case EXCP_BRK: 668 #ifdef COMPAT_FREEBSD32 669 case EXCP_BRKPT_32: 670 #endif /* COMPAT_FREEBSD32 */ 671 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr, 672 exception); 673 userret(td, frame); 674 break; 675 case EXCP_WATCHPT_EL0: 676 call_trapsignal(td, SIGTRAP, TRAP_TRACE, (void *)far, 677 exception); 678 userret(td, frame); 679 break; 680 case EXCP_MSR: 681 /* 682 * The CPU can raise EXCP_MSR when userspace executes an mrs 683 * instruction to access a special register userspace doesn't 684 * have access to. 685 */ 686 if (!undef_insn(0, frame)) 687 call_trapsignal(td, SIGILL, ILL_PRVOPC, 688 (void *)frame->tf_elr, exception); 689 userret(td, frame); 690 break; 691 case EXCP_SOFTSTP_EL0: 692 PROC_LOCK(td->td_proc); 693 if ((td->td_dbgflags & TDB_STEP) != 0) { 694 td->td_frame->tf_spsr &= ~PSR_SS; 695 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP; 696 WRITE_SPECIALREG(mdscr_el1, 697 READ_SPECIALREG(mdscr_el1) & ~MDSCR_SS); 698 } 699 PROC_UNLOCK(td->td_proc); 700 call_trapsignal(td, SIGTRAP, TRAP_TRACE, 701 (void *)frame->tf_elr, exception); 702 userret(td, frame); 703 break; 704 default: 705 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr, 706 exception); 707 userret(td, frame); 708 break; 709 } 710 711 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0, 712 ("Kernel VFP flags set while entering userspace")); 713 KASSERT( 714 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate, 715 ("Kernel VFP state in use when entering userspace")); 716 } 717 718 /* 719 * TODO: We will need to handle these later when we support ARMv8.2 RAS. 720 */ 721 void 722 do_serror(struct trapframe *frame) 723 { 724 uint64_t esr, far; 725 726 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 727 far = frame->tf_far; 728 esr = frame->tf_esr; 729 730 print_registers(frame); 731 print_gp_register("far", far); 732 printf(" esr: %16lx\n", esr); 733 panic("Unhandled System Error"); 734 } 735 736 void 737 unhandled_exception(struct trapframe *frame) 738 { 739 uint64_t esr, far; 740 741 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 742 far = frame->tf_far; 743 esr = frame->tf_esr; 744 745 print_registers(frame); 746 print_gp_register("far", far); 747 printf(" esr: %16lx\n", esr); 748 panic("Unhandled exception"); 749 } 750