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 KASSERT(td->td_md.md_spinlock_count == 0, 328 ("data abort with spinlock held")); 329 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | 330 WARN_GIANTOK, NULL, "Kernel page fault") != 0) { 331 print_registers(frame); 332 print_gp_register("far", far); 333 printf(" esr: %.16lx\n", esr); 334 panic("data abort in critical section or under mutex"); 335 } 336 337 switch (ESR_ELx_EXCEPTION(esr)) { 338 case EXCP_INSN_ABORT: 339 case EXCP_INSN_ABORT_L: 340 ftype = VM_PROT_EXECUTE; 341 break; 342 default: 343 /* 344 * If the exception was because of a read or cache operation 345 * pass a read fault type into the vm code. Cache operations 346 * need read permission but will set the WnR flag when the 347 * memory is unmapped. 348 */ 349 if ((esr & ISS_DATA_WnR) == 0 || (esr & ISS_DATA_CM) != 0) 350 ftype = VM_PROT_READ; 351 else 352 ftype = VM_PROT_WRITE; 353 break; 354 } 355 356 /* Fault in the page. */ 357 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode); 358 if (error != KERN_SUCCESS) { 359 if (lower) { 360 call_trapsignal(td, sig, ucode, (void *)far, 361 ESR_ELx_EXCEPTION(esr)); 362 } else { 363 bad_far: 364 if (td->td_intr_nesting_level == 0 && 365 pcb->pcb_onfault != 0) { 366 frame->tf_x[0] = error; 367 frame->tf_elr = pcb->pcb_onfault; 368 return; 369 } 370 371 printf("Fatal data abort:\n"); 372 print_registers(frame); 373 print_gp_register("far", far); 374 printf(" esr: %.16lx\n", esr); 375 376 #ifdef KDB 377 if (debugger_on_trap) { 378 kdb_why = KDB_WHY_TRAP; 379 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0, 380 frame); 381 kdb_why = KDB_WHY_UNSET; 382 if (handled) 383 return; 384 } 385 #endif 386 panic("vm_fault failed: %lx error %d", 387 frame->tf_elr, error); 388 } 389 } 390 391 if (lower) 392 userret(td, frame); 393 } 394 395 static void 396 print_gp_register(const char *name, uint64_t value) 397 { 398 #if defined(DDB) 399 c_db_sym_t sym; 400 const char *sym_name; 401 db_expr_t sym_value; 402 db_expr_t offset; 403 #endif 404 405 printf(" %s: %16lx", name, value); 406 #if defined(DDB) 407 /* If this looks like a kernel address try to find the symbol */ 408 if (value >= VM_MIN_KERNEL_ADDRESS) { 409 sym = db_search_symbol(value, DB_STGY_ANY, &offset); 410 if (sym != C_DB_SYM_NULL) { 411 db_symbol_values(sym, &sym_name, &sym_value); 412 printf(" (%s + %lx)", sym_name, offset); 413 } 414 } 415 #endif 416 printf("\n"); 417 } 418 419 static void 420 print_registers(struct trapframe *frame) 421 { 422 char name[4]; 423 u_int reg; 424 425 for (reg = 0; reg < nitems(frame->tf_x); reg++) { 426 snprintf(name, sizeof(name), "%sx%d", (reg < 10) ? " " : "", 427 reg); 428 print_gp_register(name, frame->tf_x[reg]); 429 } 430 printf(" sp: %16lx\n", frame->tf_sp); 431 print_gp_register(" lr", frame->tf_lr); 432 print_gp_register("elr", frame->tf_elr); 433 printf("spsr: %16lx\n", frame->tf_spsr); 434 } 435 436 #ifdef VFP 437 static void 438 fpe_trap(struct thread *td, void *addr, uint32_t exception) 439 { 440 int code; 441 442 code = FPE_FLTIDO; 443 if ((exception & ISS_FP_TFV) != 0) { 444 if ((exception & ISS_FP_IOF) != 0) 445 code = FPE_FLTINV; 446 else if ((exception & ISS_FP_DZF) != 0) 447 code = FPE_FLTDIV; 448 else if ((exception & ISS_FP_OFF) != 0) 449 code = FPE_FLTOVF; 450 else if ((exception & ISS_FP_UFF) != 0) 451 code = FPE_FLTUND; 452 else if ((exception & ISS_FP_IXF) != 0) 453 code = FPE_FLTRES; 454 } 455 call_trapsignal(td, SIGFPE, code, addr, exception); 456 } 457 #endif 458 459 /* 460 * See the comment above data_abort(). 461 */ 462 void NO_PERTHREAD_SSP 463 do_el1h_sync(struct thread *td, struct trapframe *frame) 464 { 465 uint32_t exception; 466 uint64_t esr, far; 467 int dfsc; 468 469 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 470 far = frame->tf_far; 471 /* Read the esr register to get the exception details */ 472 esr = frame->tf_esr; 473 exception = ESR_ELx_EXCEPTION(esr); 474 475 #ifdef KDTRACE_HOOKS 476 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception)) 477 return; 478 #endif 479 480 CTR4(KTR_TRAP, 481 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, 482 esr, frame->tf_elr, frame); 483 484 /* 485 * Enable debug exceptions if we aren't already handling one. They will 486 * be masked again in the exception handler's epilogue. 487 */ 488 if (exception != EXCP_BRK && exception != EXCP_WATCHPT_EL1 && 489 exception != EXCP_SOFTSTP_EL1) 490 dbg_enable(); 491 492 switch (exception) { 493 case EXCP_FP_SIMD: 494 case EXCP_TRAP_FP: 495 #ifdef VFP 496 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) { 497 vfp_restore_state(); 498 } else 499 #endif 500 { 501 print_registers(frame); 502 printf(" esr: %.16lx\n", esr); 503 panic("VFP exception in the kernel"); 504 } 505 break; 506 case EXCP_INSN_ABORT: 507 case EXCP_DATA_ABORT: 508 dfsc = esr & ISS_DATA_DFSC_MASK; 509 if (dfsc < nitems(abort_handlers) && 510 abort_handlers[dfsc] != NULL) { 511 abort_handlers[dfsc](td, frame, esr, far, 0); 512 } else { 513 print_registers(frame); 514 print_gp_register("far", far); 515 printf(" esr: %.16lx\n", esr); 516 panic("Unhandled EL1 %s abort: %x", 517 exception == EXCP_INSN_ABORT ? "instruction" : 518 "data", dfsc); 519 } 520 break; 521 case EXCP_BRK: 522 #ifdef KDTRACE_HOOKS 523 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \ 524 dtrace_invop_jump_addr != 0) { 525 dtrace_invop_jump_addr(frame); 526 break; 527 } 528 #endif 529 #ifdef KDB 530 kdb_trap(exception, 0, frame); 531 #else 532 panic("No debugger in kernel."); 533 #endif 534 break; 535 case EXCP_WATCHPT_EL1: 536 case EXCP_SOFTSTP_EL1: 537 #ifdef KDB 538 kdb_trap(exception, 0, frame); 539 #else 540 panic("No debugger in kernel."); 541 #endif 542 break; 543 case EXCP_FPAC: 544 /* We can see this if the authentication on PAC fails */ 545 print_registers(frame); 546 print_gp_register("far", far); 547 panic("FPAC kernel exception"); 548 break; 549 case EXCP_UNKNOWN: 550 if (undef_insn(1, frame)) 551 break; 552 print_registers(frame); 553 print_gp_register("far", far); 554 panic("Undefined instruction: %08x", 555 *(uint32_t *)frame->tf_elr); 556 break; 557 default: 558 print_registers(frame); 559 print_gp_register("far", far); 560 panic("Unknown kernel exception %x esr_el1 %lx", exception, 561 esr); 562 } 563 } 564 565 void 566 do_el0_sync(struct thread *td, struct trapframe *frame) 567 { 568 pcpu_bp_harden bp_harden; 569 uint32_t exception; 570 uint64_t esr, far; 571 int dfsc; 572 573 /* Check we have a sane environment when entering from userland */ 574 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS, 575 ("Invalid pcpu address from userland: %p (tpidr %lx)", 576 get_pcpu(), READ_SPECIALREG(tpidr_el1))); 577 578 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 579 far = frame->tf_far; 580 esr = frame->tf_esr; 581 exception = ESR_ELx_EXCEPTION(esr); 582 if (exception == EXCP_INSN_ABORT_L && far > VM_MAXUSER_ADDRESS) { 583 /* 584 * Userspace may be trying to train the branch predictor to 585 * attack the kernel. If we are on a CPU affected by this 586 * call the handler to clear the branch predictor state. 587 */ 588 bp_harden = PCPU_GET(bp_harden); 589 if (bp_harden != NULL) 590 bp_harden(); 591 } 592 intr_enable(); 593 594 CTR4(KTR_TRAP, 595 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr, 596 frame->tf_elr, frame); 597 598 switch (exception) { 599 case EXCP_FP_SIMD: 600 #ifdef VFP 601 vfp_restore_state(); 602 #else 603 panic("VFP exception in userland"); 604 #endif 605 break; 606 case EXCP_TRAP_FP: 607 #ifdef VFP 608 fpe_trap(td, (void *)frame->tf_elr, esr); 609 userret(td, frame); 610 #else 611 panic("VFP exception in userland"); 612 #endif 613 break; 614 case EXCP_SVE: 615 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)frame->tf_elr, 616 exception); 617 userret(td, frame); 618 break; 619 case EXCP_SVC32: 620 case EXCP_SVC64: 621 svc_handler(td, frame); 622 break; 623 case EXCP_INSN_ABORT_L: 624 case EXCP_DATA_ABORT_L: 625 case EXCP_DATA_ABORT: 626 dfsc = esr & ISS_DATA_DFSC_MASK; 627 if (dfsc < nitems(abort_handlers) && 628 abort_handlers[dfsc] != NULL) 629 abort_handlers[dfsc](td, frame, esr, far, 1); 630 else { 631 print_registers(frame); 632 print_gp_register("far", far); 633 printf(" esr: %.16lx\n", esr); 634 panic("Unhandled EL0 %s abort: %x", 635 exception == EXCP_INSN_ABORT_L ? "instruction" : 636 "data", dfsc); 637 } 638 break; 639 case EXCP_UNKNOWN: 640 if (!undef_insn(0, frame)) 641 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far, 642 exception); 643 userret(td, frame); 644 break; 645 case EXCP_FPAC: 646 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr, 647 exception); 648 userret(td, frame); 649 break; 650 case EXCP_SP_ALIGN: 651 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp, 652 exception); 653 userret(td, frame); 654 break; 655 case EXCP_PC_ALIGN: 656 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr, 657 exception); 658 userret(td, frame); 659 break; 660 case EXCP_BRKPT_EL0: 661 case EXCP_BRK: 662 #ifdef COMPAT_FREEBSD32 663 case EXCP_BRKPT_32: 664 #endif /* COMPAT_FREEBSD32 */ 665 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr, 666 exception); 667 userret(td, frame); 668 break; 669 case EXCP_WATCHPT_EL0: 670 call_trapsignal(td, SIGTRAP, TRAP_TRACE, (void *)far, 671 exception); 672 userret(td, frame); 673 break; 674 case EXCP_MSR: 675 /* 676 * The CPU can raise EXCP_MSR when userspace executes an mrs 677 * instruction to access a special register userspace doesn't 678 * have access to. 679 */ 680 if (!undef_insn(0, frame)) 681 call_trapsignal(td, SIGILL, ILL_PRVOPC, 682 (void *)frame->tf_elr, exception); 683 userret(td, frame); 684 break; 685 case EXCP_SOFTSTP_EL0: 686 PROC_LOCK(td->td_proc); 687 if ((td->td_dbgflags & TDB_STEP) != 0) { 688 td->td_frame->tf_spsr &= ~PSR_SS; 689 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP; 690 WRITE_SPECIALREG(mdscr_el1, 691 READ_SPECIALREG(mdscr_el1) & ~MDSCR_SS); 692 } 693 PROC_UNLOCK(td->td_proc); 694 call_trapsignal(td, SIGTRAP, TRAP_TRACE, 695 (void *)frame->tf_elr, exception); 696 userret(td, frame); 697 break; 698 default: 699 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr, 700 exception); 701 userret(td, frame); 702 break; 703 } 704 705 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0, 706 ("Kernel VFP flags set while entering userspace")); 707 KASSERT( 708 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate, 709 ("Kernel VFP state in use when entering userspace")); 710 } 711 712 /* 713 * TODO: We will need to handle these later when we support ARMv8.2 RAS. 714 */ 715 void 716 do_serror(struct trapframe *frame) 717 { 718 uint64_t esr, far; 719 720 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 721 far = frame->tf_far; 722 esr = frame->tf_esr; 723 724 print_registers(frame); 725 print_gp_register("far", far); 726 printf(" esr: %.16lx\n", esr); 727 panic("Unhandled System Error"); 728 } 729 730 void 731 unhandled_exception(struct trapframe *frame) 732 { 733 uint64_t esr, far; 734 735 kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0); 736 far = frame->tf_far; 737 esr = frame->tf_esr; 738 739 print_registers(frame); 740 print_gp_register("far", far); 741 printf(" esr: %.16lx\n", esr); 742 panic("Unhandled exception"); 743 } 744