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 (spinlock count %d != 0)", 333 td->td_md.md_spinlock_count); 334 } 335 #endif 336 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | 337 WARN_GIANTOK, NULL, "Kernel page fault") != 0) { 338 print_registers(frame); 339 print_gp_register("far", far); 340 printf(" esr: %16lx\n", esr); 341 panic("data abort in critical section or under mutex"); 342 } 343 344 switch (ESR_ELx_EXCEPTION(esr)) { 345 case EXCP_INSN_ABORT: 346 case EXCP_INSN_ABORT_L: 347 ftype = VM_PROT_EXECUTE; 348 break; 349 default: 350 /* 351 * If the exception was because of a read or cache operation 352 * pass a read fault type into the vm code. Cache operations 353 * need read permission but will set the WnR flag when the 354 * memory is unmapped. 355 */ 356 if ((esr & ISS_DATA_WnR) == 0 || (esr & ISS_DATA_CM) != 0) 357 ftype = VM_PROT_READ; 358 else 359 ftype = VM_PROT_WRITE; 360 break; 361 } 362 363 /* Fault in the page. */ 364 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode); 365 if (error != KERN_SUCCESS) { 366 if (lower) { 367 call_trapsignal(td, sig, ucode, (void *)far, 368 ESR_ELx_EXCEPTION(esr)); 369 } else { 370 bad_far: 371 if (td->td_intr_nesting_level == 0 && 372 pcb->pcb_onfault != 0) { 373 frame->tf_x[0] = error; 374 frame->tf_elr = pcb->pcb_onfault; 375 return; 376 } 377 378 printf("Fatal data abort:\n"); 379 print_registers(frame); 380 print_gp_register("far", far); 381 printf(" esr: %16lx\n", esr); 382 383 #ifdef KDB 384 if (debugger_on_trap) { 385 kdb_why = KDB_WHY_TRAP; 386 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0, 387 frame); 388 kdb_why = KDB_WHY_UNSET; 389 if (handled) 390 return; 391 } 392 #endif 393 panic("vm_fault failed: %lx error %d", 394 frame->tf_elr, error); 395 } 396 } 397 398 if (lower) 399 userret(td, frame); 400 } 401 402 static void 403 print_gp_register(const char *name, uint64_t value) 404 { 405 #if defined(DDB) 406 c_db_sym_t sym; 407 const char *sym_name; 408 db_expr_t sym_value; 409 db_expr_t offset; 410 #endif 411 412 printf(" %s: %16lx", name, value); 413 #if defined(DDB) 414 /* If this looks like a kernel address try to find the symbol */ 415 if (value >= VM_MIN_KERNEL_ADDRESS) { 416 sym = db_search_symbol(value, DB_STGY_ANY, &offset); 417 if (sym != C_DB_SYM_NULL) { 418 db_symbol_values(sym, &sym_name, &sym_value); 419 printf(" (%s + %lx)", sym_name, offset); 420 } 421 } 422 #endif 423 printf("\n"); 424 } 425 426 static void 427 print_registers(struct trapframe *frame) 428 { 429 char name[4]; 430 u_int reg; 431 432 for (reg = 0; reg < nitems(frame->tf_x); reg++) { 433 snprintf(name, sizeof(name), "%sx%d", (reg < 10) ? " " : "", 434 reg); 435 print_gp_register(name, frame->tf_x[reg]); 436 } 437 printf(" sp: %16lx\n", frame->tf_sp); 438 print_gp_register(" lr", frame->tf_lr); 439 print_gp_register("elr", frame->tf_elr); 440 printf("spsr: %16lx\n", frame->tf_spsr); 441 } 442 443 #ifdef VFP 444 static void 445 fpe_trap(struct thread *td, void *addr, uint32_t exception) 446 { 447 int code; 448 449 code = FPE_FLTIDO; 450 if ((exception & ISS_FP_TFV) != 0) { 451 if ((exception & ISS_FP_IOF) != 0) 452 code = FPE_FLTINV; 453 else if ((exception & ISS_FP_DZF) != 0) 454 code = FPE_FLTDIV; 455 else if ((exception & ISS_FP_OFF) != 0) 456 code = FPE_FLTOVF; 457 else if ((exception & ISS_FP_UFF) != 0) 458 code = FPE_FLTUND; 459 else if ((exception & ISS_FP_IXF) != 0) 460 code = FPE_FLTRES; 461 } 462 call_trapsignal(td, SIGFPE, code, addr, exception); 463 } 464 #endif 465 466 /* 467 * See the comment above data_abort(). 468 */ 469 void NO_PERTHREAD_SSP 470 do_el1h_sync(struct thread *td, struct trapframe *frame) 471 { 472 uint32_t exception; 473 uint64_t esr, far; 474 int dfsc; 475 476 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 477 far = frame->tf_far; 478 /* Read the esr register to get the exception details */ 479 esr = frame->tf_esr; 480 exception = ESR_ELx_EXCEPTION(esr); 481 482 #ifdef KDTRACE_HOOKS 483 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception)) 484 return; 485 #endif 486 487 CTR4(KTR_TRAP, 488 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, 489 esr, frame->tf_elr, frame); 490 491 /* 492 * Enable debug exceptions if we aren't already handling one. They will 493 * be masked again in the exception handler's epilogue. 494 */ 495 if (exception != EXCP_BRK && exception != EXCP_WATCHPT_EL1 && 496 exception != EXCP_SOFTSTP_EL1) 497 dbg_enable(); 498 499 switch (exception) { 500 case EXCP_FP_SIMD: 501 case EXCP_TRAP_FP: 502 #ifdef VFP 503 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) { 504 vfp_restore_state(); 505 } else 506 #endif 507 { 508 print_registers(frame); 509 printf(" esr: %16lx\n", esr); 510 panic("VFP exception in the kernel"); 511 } 512 break; 513 case EXCP_INSN_ABORT: 514 case EXCP_DATA_ABORT: 515 dfsc = esr & ISS_DATA_DFSC_MASK; 516 if (dfsc < nitems(abort_handlers) && 517 abort_handlers[dfsc] != NULL) { 518 abort_handlers[dfsc](td, frame, esr, far, 0); 519 } else { 520 print_registers(frame); 521 print_gp_register("far", far); 522 printf(" esr: %16lx\n", esr); 523 panic("Unhandled EL1 %s abort: %x", 524 exception == EXCP_INSN_ABORT ? "instruction" : 525 "data", dfsc); 526 } 527 break; 528 case EXCP_BRK: 529 #ifdef KDTRACE_HOOKS 530 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \ 531 dtrace_invop_jump_addr != 0) { 532 dtrace_invop_jump_addr(frame); 533 break; 534 } 535 #endif 536 #ifdef KDB 537 kdb_trap(exception, 0, frame); 538 #else 539 panic("No debugger in kernel."); 540 #endif 541 break; 542 case EXCP_WATCHPT_EL1: 543 case EXCP_SOFTSTP_EL1: 544 #ifdef KDB 545 kdb_trap(exception, 0, frame); 546 #else 547 panic("No debugger in kernel."); 548 #endif 549 break; 550 case EXCP_FPAC: 551 /* We can see this if the authentication on PAC fails */ 552 print_registers(frame); 553 print_gp_register("far", far); 554 panic("FPAC kernel exception"); 555 break; 556 case EXCP_UNKNOWN: 557 if (undef_insn(1, frame)) 558 break; 559 print_registers(frame); 560 print_gp_register("far", far); 561 panic("Undefined instruction: %08x", 562 *(uint32_t *)frame->tf_elr); 563 break; 564 default: 565 print_registers(frame); 566 print_gp_register("far", far); 567 panic("Unknown kernel exception %x esr_el1 %lx", exception, 568 esr); 569 } 570 } 571 572 void 573 do_el0_sync(struct thread *td, struct trapframe *frame) 574 { 575 pcpu_bp_harden bp_harden; 576 uint32_t exception; 577 uint64_t esr, far; 578 int dfsc; 579 580 /* Check we have a sane environment when entering from userland */ 581 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS, 582 ("Invalid pcpu address from userland: %p (tpidr %lx)", 583 get_pcpu(), READ_SPECIALREG(tpidr_el1))); 584 585 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 586 far = frame->tf_far; 587 esr = frame->tf_esr; 588 exception = ESR_ELx_EXCEPTION(esr); 589 if (exception == EXCP_INSN_ABORT_L && far > VM_MAXUSER_ADDRESS) { 590 /* 591 * Userspace may be trying to train the branch predictor to 592 * attack the kernel. If we are on a CPU affected by this 593 * call the handler to clear the branch predictor state. 594 */ 595 bp_harden = PCPU_GET(bp_harden); 596 if (bp_harden != NULL) 597 bp_harden(); 598 } 599 intr_enable(); 600 601 CTR4(KTR_TRAP, 602 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr, 603 frame->tf_elr, frame); 604 605 switch (exception) { 606 case EXCP_FP_SIMD: 607 #ifdef VFP 608 vfp_restore_state(); 609 #else 610 panic("VFP exception in userland"); 611 #endif 612 break; 613 case EXCP_TRAP_FP: 614 #ifdef VFP 615 fpe_trap(td, (void *)frame->tf_elr, esr); 616 userret(td, frame); 617 #else 618 panic("VFP exception in userland"); 619 #endif 620 break; 621 case EXCP_SVE: 622 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)frame->tf_elr, 623 exception); 624 userret(td, frame); 625 break; 626 case EXCP_SVC32: 627 case EXCP_SVC64: 628 svc_handler(td, frame); 629 break; 630 case EXCP_INSN_ABORT_L: 631 case EXCP_DATA_ABORT_L: 632 case EXCP_DATA_ABORT: 633 dfsc = esr & ISS_DATA_DFSC_MASK; 634 if (dfsc < nitems(abort_handlers) && 635 abort_handlers[dfsc] != NULL) 636 abort_handlers[dfsc](td, frame, esr, far, 1); 637 else { 638 print_registers(frame); 639 print_gp_register("far", far); 640 printf(" esr: %16lx\n", esr); 641 panic("Unhandled EL0 %s abort: %x", 642 exception == EXCP_INSN_ABORT_L ? "instruction" : 643 "data", dfsc); 644 } 645 break; 646 case EXCP_UNKNOWN: 647 if (!undef_insn(0, frame)) 648 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far, 649 exception); 650 userret(td, frame); 651 break; 652 case EXCP_FPAC: 653 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr, 654 exception); 655 userret(td, frame); 656 break; 657 case EXCP_SP_ALIGN: 658 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp, 659 exception); 660 userret(td, frame); 661 break; 662 case EXCP_PC_ALIGN: 663 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr, 664 exception); 665 userret(td, frame); 666 break; 667 case EXCP_BRKPT_EL0: 668 case EXCP_BRK: 669 #ifdef COMPAT_FREEBSD32 670 case EXCP_BRKPT_32: 671 #endif /* COMPAT_FREEBSD32 */ 672 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr, 673 exception); 674 userret(td, frame); 675 break; 676 case EXCP_WATCHPT_EL0: 677 call_trapsignal(td, SIGTRAP, TRAP_TRACE, (void *)far, 678 exception); 679 userret(td, frame); 680 break; 681 case EXCP_MSR: 682 /* 683 * The CPU can raise EXCP_MSR when userspace executes an mrs 684 * instruction to access a special register userspace doesn't 685 * have access to. 686 */ 687 if (!undef_insn(0, frame)) 688 call_trapsignal(td, SIGILL, ILL_PRVOPC, 689 (void *)frame->tf_elr, exception); 690 userret(td, frame); 691 break; 692 case EXCP_SOFTSTP_EL0: 693 PROC_LOCK(td->td_proc); 694 if ((td->td_dbgflags & TDB_STEP) != 0) { 695 td->td_frame->tf_spsr &= ~PSR_SS; 696 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP; 697 WRITE_SPECIALREG(mdscr_el1, 698 READ_SPECIALREG(mdscr_el1) & ~MDSCR_SS); 699 } 700 PROC_UNLOCK(td->td_proc); 701 call_trapsignal(td, SIGTRAP, TRAP_TRACE, 702 (void *)frame->tf_elr, exception); 703 userret(td, frame); 704 break; 705 default: 706 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr, 707 exception); 708 userret(td, frame); 709 break; 710 } 711 712 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0, 713 ("Kernel VFP flags set while entering userspace")); 714 KASSERT( 715 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate, 716 ("Kernel VFP state in use when entering userspace")); 717 } 718 719 /* 720 * TODO: We will need to handle these later when we support ARMv8.2 RAS. 721 */ 722 void 723 do_serror(struct trapframe *frame) 724 { 725 uint64_t esr, far; 726 727 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 728 far = frame->tf_far; 729 esr = frame->tf_esr; 730 731 print_registers(frame); 732 print_gp_register("far", far); 733 printf(" esr: %16lx\n", esr); 734 panic("Unhandled System Error"); 735 } 736 737 void 738 unhandled_exception(struct trapframe *frame) 739 { 740 uint64_t esr, far; 741 742 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 743 far = frame->tf_far; 744 esr = frame->tf_esr; 745 746 print_registers(frame); 747 print_gp_register("far", far); 748 printf(" esr: %16lx\n", esr); 749 panic("Unhandled exception"); 750 } 751