1 /* $NetBSD: trap.c,v 1.130 2025/06/20 17:02:18 bouyer Exp $ */ 2 3 /* 4 * Copyright (c) 1998, 2000, 2017 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum, and by Maxime Villard. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1990 The Regents of the University of California. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to Berkeley by 37 * the University of Utah, and William Jolitz. 38 * 39 * Redistribution and use in source and binary forms, with or without 40 * modification, are permitted provided that the following conditions 41 * are met: 42 * 1. Redistributions of source code must retain the above copyright 43 * notice, this list of conditions and the following disclaimer. 44 * 2. Redistributions in binary form must reproduce the above copyright 45 * notice, this list of conditions and the following disclaimer in the 46 * documentation and/or other materials provided with the distribution. 47 * 3. Neither the name of the University nor the names of its contributors 48 * may be used to endorse or promote products derived from this software 49 * without specific prior written permission. 50 * 51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 * 63 * @(#)trap.c 7.4 (Berkeley) 5/13/91 64 */ 65 66 #include <sys/cdefs.h> 67 __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.130 2025/06/20 17:02:18 bouyer Exp $"); 68 69 #include "opt_ddb.h" 70 #include "opt_kgdb.h" 71 #include "opt_xen.h" 72 #include "opt_dtrace.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/proc.h> 77 #include <sys/acct.h> 78 #include <sys/kauth.h> 79 #include <sys/kernel.h> 80 #include <sys/kmem.h> 81 #include <sys/ras.h> 82 #include <sys/signal.h> 83 #include <sys/syscall.h> 84 #include <sys/cpu.h> 85 #include <sys/ucontext.h> 86 #include <sys/module_hook.h> 87 #include <sys/compat_stub.h> 88 89 #include <uvm/uvm_extern.h> 90 91 #include <machine/cpufunc.h> 92 #include <x86/fpu.h> 93 #include <x86/dbregs.h> 94 #include <machine/psl.h> 95 #include <machine/reg.h> 96 #include <machine/trap.h> 97 #include <machine/userret.h> 98 #include <machine/db_machdep.h> 99 100 #include <x86/nmi.h> 101 102 #ifndef XENPV 103 #include "isa.h" 104 #endif 105 106 #include <sys/kgdb.h> 107 108 #ifdef KDTRACE_HOOKS 109 #include <sys/dtrace_bsd.h> 110 /* 111 * This is a hook which is initialized by the dtrace module to handle traps 112 * which might occur during DTrace probe execution. 113 */ 114 dtrace_trap_func_t dtrace_trap_func = NULL; 115 dtrace_doubletrap_func_t dtrace_doubletrap_func = NULL; 116 #endif 117 118 /* 119 * Module hook for amd64_oosyscall 120 */ 121 struct amd64_oosyscall_hook_t amd64_oosyscall_hook; 122 123 void nmitrap(struct trapframe *); 124 void doubletrap(struct trapframe *); 125 void trap(struct trapframe *); 126 127 const char * const trap_type[] = { 128 "privileged instruction fault", /* 0 T_PRIVINFLT */ 129 "breakpoint trap", /* 1 T_BPTFLT */ 130 "arithmetic trap", /* 2 T_ARITHTRAP */ 131 "asynchronous system trap", /* 3 T_ASTFLT */ 132 "protection fault", /* 4 T_PROTFLT */ 133 "trace trap", /* 5 T_TRCTRAP */ 134 "page fault", /* 6 T_PAGEFLT */ 135 "alignment fault", /* 7 T_ALIGNFLT */ 136 "integer divide fault", /* 8 T_DIVIDE */ 137 "non-maskable interrupt", /* 9 T_NMI */ 138 "overflow trap", /* 10 T_OFLOW */ 139 "bounds check fault", /* 11 T_BOUND */ 140 "FPU not available fault", /* 12 T_DNA */ 141 "double fault", /* 13 T_DOUBLEFLT */ 142 "FPU operand fetch fault", /* 14 T_FPOPFLT */ 143 "invalid TSS fault", /* 15 T_TSSFLT */ 144 "segment not present fault", /* 16 T_SEGNPFLT */ 145 "stack fault", /* 17 T_STKFLT */ 146 "machine check fault", /* 18 T_MCA */ 147 "SSE FP exception", /* 19 T_XMM */ 148 "reserved trap", /* 20 T_RESERVED */ 149 }; 150 int trap_types = __arraycount(trap_type); 151 152 #ifdef TRAP_SIGDEBUG 153 static void sigdebug(const struct trapframe *, const ksiginfo_t *, int); 154 #define SIGDEBUG(a, b, c) sigdebug(a, b, c) 155 #else 156 #define SIGDEBUG(a, b, c) 157 #endif 158 159 static void 160 onfault_restore(struct trapframe *frame, void *onfault, int error) 161 { 162 frame->tf_rip = (uintptr_t)onfault; 163 frame->tf_rax = error; 164 } 165 166 static void * 167 onfault_handler(const struct pcb *pcb, const struct trapframe *tf) 168 { 169 struct onfault_table { 170 uintptr_t start; 171 uintptr_t end; 172 void *handler; 173 }; 174 extern const struct onfault_table onfault_table[]; 175 const struct onfault_table *p; 176 uintptr_t pc; 177 178 if (pcb->pcb_onfault != NULL) { 179 return pcb->pcb_onfault; 180 } 181 182 pc = tf->tf_rip; 183 for (p = onfault_table; p->start; p++) { 184 if (p->start <= pc && pc < p->end) { 185 return p->handler; 186 } 187 } 188 return NULL; 189 } 190 191 static void 192 trap_print(const struct trapframe *frame, const lwp_t *l) 193 { 194 const int type = frame->tf_trapno; 195 196 if (frame->tf_trapno < trap_types) { 197 printf("fatal %s", trap_type[type]); 198 } else { 199 printf("unknown trap %d", type); 200 } 201 printf(" in %s mode\n", (type & T_USER) ? "user" : "supervisor"); 202 203 printf("trap type %d code %#lx rip %#lx cs %#lx rflags %#lx cr2 %#lx " 204 "ilevel %#x rsp %#lx\n", 205 type, frame->tf_err, (u_long)frame->tf_rip, frame->tf_cs, 206 frame->tf_rflags, rcr2(), curcpu()->ci_ilevel, frame->tf_rsp); 207 208 printf("curlwp %p pid %d.%d lowest kstack %p\n", 209 l, l->l_proc->p_pid, l->l_lid, KSTACK_LOWEST_ADDR(l)); 210 } 211 212 void 213 nmitrap(struct trapframe *frame) 214 { 215 const int type = T_NMI; 216 217 if (nmi_dispatch(frame)) 218 return; 219 /* NMI can be hooked up to a pushbutton for debugging */ 220 if (kgdb_trap(type, frame)) 221 return; 222 if (kdb_trap(type, 0, frame)) 223 return; 224 /* machine/parity/power fail/"kitchen sink" faults */ 225 226 x86_nmi(); 227 } 228 229 void 230 doubletrap(struct trapframe *frame) 231 { 232 const int type = T_DOUBLEFLT; 233 struct lwp *l = curlwp; 234 235 trap_print(frame, l); 236 237 if (kdb_trap(type, 0, frame)) 238 return; 239 if (kgdb_trap(type, frame)) 240 return; 241 242 panic("double fault"); 243 } 244 245 /* 246 * trap(frame): exception, fault, and trap interface to BSD kernel. 247 * 248 * This common code is called from assembly language IDT gate entry routines 249 * that prepare a suitable stack frame, and restore this frame after the 250 * exception has been processed. Note that the effect is as if the arguments 251 * were passed call by reference. 252 * 253 * Note that the fpu traps (07 T_DNA, 10 T_ARITHTRAP and 13 T_XMM) 254 * jump directly into the code in x86/fpu.c so they get processed 255 * without interrupts being enabled. 256 */ 257 void 258 trap(struct trapframe *frame) 259 { 260 struct lwp *l = curlwp; 261 struct proc *p; 262 struct pcb *pcb; 263 extern char kcopy_fault[]; 264 ksiginfo_t ksi; 265 void *onfault; 266 int type, error; 267 uint64_t cr2; 268 bool pfail; 269 270 if (__predict_true(l != NULL)) { 271 pcb = lwp_getpcb(l); 272 p = l->l_proc; 273 } else { 274 /* 275 * This can happen eg on break points in early on boot. 276 */ 277 pcb = NULL; 278 p = NULL; 279 } 280 type = frame->tf_trapno; 281 282 if (!KERNELMODE(frame->tf_cs)) { 283 type |= T_USER; 284 l->l_md.md_regs = frame; 285 } 286 287 #ifdef KDTRACE_HOOKS 288 /* 289 * A trap can occur while DTrace executes a probe. Before 290 * executing the probe, DTrace blocks re-scheduling and sets 291 * a flag in its per-cpu flags to indicate that it doesn't 292 * want to fault. On returning from the probe, the no-fault 293 * flag is cleared and finally re-scheduling is enabled. 294 * 295 * If the DTrace kernel module has registered a trap handler, 296 * call it and if it returns non-zero, assume that it has 297 * handled the trap and modified the trap frame so that this 298 * function can return normally. 299 */ 300 if ((type == T_PROTFLT || type == T_PAGEFLT) && 301 dtrace_trap_func != NULL) { 302 if ((*dtrace_trap_func)(frame, type)) { 303 return; 304 } 305 } 306 #endif 307 308 switch (type) { 309 310 default: 311 we_re_toast: 312 trap_print(frame, l); 313 314 if (kdb_trap(type, 0, frame)) 315 return; 316 if (kgdb_trap(type, frame)) 317 return; 318 /* 319 * If this is a breakpoint, don't panic if we're not connected. 320 */ 321 if (type == T_BPTFLT && kgdb_disconnected()) { 322 printf("kgdb: ignored %s\n", trap_type[type]); 323 return; 324 } 325 panic("trap"); 326 /*NOTREACHED*/ 327 328 case T_PROTFLT: 329 case T_SEGNPFLT: 330 case T_ALIGNFLT: 331 case T_STKFLT: 332 case T_TSSFLT: 333 if (p == NULL) 334 goto we_re_toast; 335 336 /* Check for copyin/copyout fault. */ 337 onfault = onfault_handler(pcb, frame); 338 if (onfault != NULL) { 339 onfault_restore(frame, onfault, EFAULT); 340 return; 341 } 342 343 goto we_re_toast; 344 345 case T_PROTFLT|T_USER: /* protection fault */ 346 { int hook_ret; 347 348 MODULE_HOOK_CALL(amd64_oosyscall_hook, (p, frame), 349 ENOSYS, hook_ret); 350 if (hook_ret == 0) { 351 /* Do the syscall */ 352 p->p_md.md_syscall(frame); 353 goto out; 354 } 355 } 356 /* FALLTHROUGH */ 357 case T_TSSFLT|T_USER: 358 case T_SEGNPFLT|T_USER: 359 case T_STKFLT|T_USER: 360 case T_ALIGNFLT|T_USER: 361 KSI_INIT_TRAP(&ksi); 362 ksi.ksi_trap = type & ~T_USER; 363 ksi.ksi_addr = (void *)frame->tf_rip; 364 switch (type) { 365 case T_SEGNPFLT|T_USER: 366 case T_STKFLT|T_USER: 367 ksi.ksi_signo = SIGBUS; 368 ksi.ksi_code = BUS_ADRERR; 369 break; 370 case T_TSSFLT|T_USER: 371 ksi.ksi_signo = SIGBUS; 372 ksi.ksi_code = BUS_OBJERR; 373 break; 374 case T_ALIGNFLT|T_USER: 375 ksi.ksi_signo = SIGBUS; 376 ksi.ksi_code = BUS_ADRALN; 377 break; 378 case T_PROTFLT|T_USER: 379 ksi.ksi_signo = SIGSEGV; 380 ksi.ksi_code = SEGV_ACCERR; 381 break; 382 default: 383 KASSERT(0); 384 break; 385 } 386 goto trapsignal; 387 388 case T_PRIVINFLT|T_USER: /* privileged instruction fault */ 389 case T_FPOPFLT|T_USER: /* coprocessor operand fault */ 390 KSI_INIT_TRAP(&ksi); 391 ksi.ksi_signo = SIGILL; 392 ksi.ksi_trap = type & ~T_USER; 393 ksi.ksi_addr = (void *) frame->tf_rip; 394 switch (type) { 395 case T_PRIVINFLT|T_USER: 396 ksi.ksi_code = ILL_PRVOPC; 397 break; 398 case T_FPOPFLT|T_USER: 399 ksi.ksi_code = ILL_COPROC; 400 break; 401 default: 402 KASSERT(0); 403 break; 404 } 405 goto trapsignal; 406 407 case T_ASTFLT|T_USER: 408 /* Allow process switch. */ 409 //curcpu()->ci_data.cpu_nast++; 410 if (l->l_pflag & LP_OWEUPC) { 411 l->l_pflag &= ~LP_OWEUPC; 412 ADDUPROF(l); 413 } 414 goto out; 415 416 case T_BOUND|T_USER: 417 case T_OFLOW|T_USER: 418 case T_DIVIDE|T_USER: 419 KSI_INIT_TRAP(&ksi); 420 ksi.ksi_signo = SIGFPE; 421 ksi.ksi_trap = type & ~T_USER; 422 ksi.ksi_addr = (void *)frame->tf_rip; 423 switch (type) { 424 case T_BOUND|T_USER: 425 ksi.ksi_code = FPE_FLTSUB; 426 break; 427 case T_OFLOW|T_USER: 428 ksi.ksi_code = FPE_INTOVF; 429 break; 430 case T_DIVIDE|T_USER: 431 ksi.ksi_code = FPE_INTDIV; 432 break; 433 default: 434 KASSERT(0); 435 break; 436 } 437 goto trapsignal; 438 439 case T_PAGEFLT: 440 /* Allow page faults in kernel mode. */ 441 if (__predict_false(l == NULL)) 442 goto we_re_toast; 443 444 onfault = pcb->pcb_onfault; 445 446 if (cpu_intr_p() || (l->l_pflag & LP_INTR) != 0) { 447 goto we_re_toast; 448 } 449 450 cr2 = rcr2(); 451 452 if (frame->tf_err & PGEX_I) { 453 /* SMEP might have brought us here */ 454 if (cr2 < VM_MAXUSER_ADDRESS) { 455 printf("prevented execution of %p (SMEP)\n", 456 (void *)cr2); 457 goto we_re_toast; 458 } 459 } 460 461 if ((frame->tf_err & PGEX_P) && 462 cr2 < VM_MAXUSER_ADDRESS) { 463 /* SMAP might have brought us here */ 464 if (onfault_handler(pcb, frame) == NULL) { 465 printf("prevented access to %p (SMAP)\n", 466 (void *)cr2); 467 goto we_re_toast; 468 } 469 } 470 471 goto pagefltcommon; 472 473 case T_PAGEFLT|T_USER: { 474 register vaddr_t va; 475 register struct vmspace *vm; 476 register struct vm_map *map; 477 vm_prot_t ftype; 478 extern struct vm_map *kernel_map; 479 480 cr2 = rcr2(); 481 if (p->p_emul->e_usertrap != NULL && 482 (*p->p_emul->e_usertrap)(l, cr2, frame) != 0) 483 return; 484 pagefltcommon: 485 vm = p->p_vmspace; 486 if (__predict_false(vm == NULL)) { 487 goto we_re_toast; 488 } 489 pcb->pcb_cr2 = cr2; 490 va = trunc_page((vaddr_t)cr2); 491 /* 492 * It is only a kernel address space fault iff: 493 * 1. (type & T_USER) == 0 and 494 * 2. pcb_onfault not set or 495 * 3. pcb_onfault set but supervisor space fault 496 * The last can occur during an exec() copyin where the 497 * argument space is lazy-allocated. 498 */ 499 if (type == T_PAGEFLT && va >= VM_MIN_KERNEL_ADDRESS) 500 map = kernel_map; 501 else 502 map = &vm->vm_map; 503 if (frame->tf_err & PGEX_W) 504 ftype = VM_PROT_WRITE; 505 else if (frame->tf_err & PGEX_I) 506 ftype = VM_PROT_EXECUTE; 507 else 508 ftype = VM_PROT_READ; 509 510 #ifdef DIAGNOSTIC 511 if (map == kernel_map && va == 0) { 512 printf("trap: bad kernel access at %lx\n", va); 513 goto we_re_toast; 514 } 515 #endif 516 #ifdef XENPV 517 /* Check to see if interrupts are enabled (ie; no events are masked) */ 518 KASSERT(x86_read_psl() == 0); 519 #endif 520 /* Fault the original page in. */ 521 onfault = pcb->pcb_onfault; 522 pcb->pcb_onfault = NULL; 523 error = uvm_fault(map, va, ftype); 524 pcb->pcb_onfault = onfault; 525 if (error == 0) { 526 if (map != kernel_map && (void *)va >= vm->vm_maxsaddr) 527 uvm_grow(p, va); 528 529 pfail = false; 530 while (type == T_PAGEFLT) { 531 /* 532 * we need to switch pmap now if we're in 533 * the middle of copyin/out. 534 * 535 * but we don't need to do so for kcopy as 536 * it never touch userspace. 537 */ 538 kpreempt_disable(); 539 if (curcpu()->ci_want_pmapload) { 540 onfault = onfault_handler(pcb, frame); 541 if (onfault != kcopy_fault) { 542 pmap_load(); 543 } 544 } 545 /* 546 * We need to keep the pmap loaded and 547 * so avoid being preempted until back 548 * into the copy functions. Disable 549 * interrupts at the hardware level before 550 * re-enabling preemption. Interrupts 551 * will be re-enabled by 'iret' when 552 * returning back out of the trap stub. 553 * They'll only be re-enabled when the 554 * program counter is once again in 555 * the copy functions, and so visible 556 * to cpu_kpreempt_exit(). 557 */ 558 x86_disable_intr(); 559 l->l_nopreempt--; 560 if (l->l_nopreempt > 0 || !l->l_dopreempt || 561 pfail) { 562 return; 563 } 564 x86_enable_intr(); 565 /* 566 * If preemption fails for some reason, 567 * don't retry it. The conditions won't 568 * change under our nose. 569 */ 570 pfail = kpreempt(0); 571 } 572 goto out; 573 } 574 575 if (type == T_PAGEFLT) { 576 onfault = onfault_handler(pcb, frame); 577 if (onfault != NULL) { 578 onfault_restore(frame, onfault, error); 579 return; 580 } 581 582 printf("uvm_fault(%p, 0x%lx, %d) -> %x\n", 583 map, va, ftype, error); 584 goto we_re_toast; 585 } 586 587 KSI_INIT_TRAP(&ksi); 588 ksi.ksi_trap = type & ~T_USER; 589 ksi.ksi_addr = (void *)cr2; 590 switch (error) { 591 case EINVAL: 592 ksi.ksi_signo = SIGBUS; 593 ksi.ksi_code = BUS_ADRERR; 594 break; 595 case EACCES: 596 ksi.ksi_signo = SIGSEGV; 597 ksi.ksi_code = SEGV_ACCERR; 598 error = EFAULT; 599 break; 600 case ENOMEM: 601 ksi.ksi_signo = SIGKILL; 602 printf("UVM: pid %d.%d (%s), uid %d killed: " 603 "out of swap\n", p->p_pid, l->l_lid, p->p_comm, 604 l->l_cred ? kauth_cred_geteuid(l->l_cred) : -1); 605 break; 606 default: 607 ksi.ksi_signo = SIGSEGV; 608 ksi.ksi_code = SEGV_MAPERR; 609 break; 610 } 611 612 SIGDEBUG(frame, &ksi, error); 613 (*p->p_emul->e_trapsignal)(l, &ksi); 614 break; 615 } 616 617 case T_TRCTRAP: 618 /* 619 * Ignore debug register trace traps due to 620 * accesses in the user's address space, which 621 * can happen under several conditions such as 622 * if a user sets a watchpoint on a buffer and 623 * then passes that buffer to a system call. 624 * We still want to get TRCTRAPS for addresses 625 * in kernel space because that is useful when 626 * debugging the kernel. 627 */ 628 if (x86_dbregs_user_trap()) 629 break; 630 631 goto we_re_toast; 632 633 case T_BPTFLT|T_USER: /* bpt instruction fault */ 634 case T_TRCTRAP|T_USER: /* trace trap */ 635 /* 636 * Don't go single-stepping into a RAS. 637 */ 638 if (p->p_raslist == NULL || 639 (ras_lookup(p, (void *)frame->tf_rip) == (void *)-1)) { 640 KSI_INIT_TRAP(&ksi); 641 ksi.ksi_signo = SIGTRAP; 642 ksi.ksi_trap = type & ~T_USER; 643 if (x86_dbregs_user_trap()) { 644 x86_dbregs_store_dr6(l); 645 ksi.ksi_code = TRAP_DBREG; 646 } else if (type == (T_BPTFLT|T_USER)) 647 ksi.ksi_code = TRAP_BRKPT; 648 else 649 ksi.ksi_code = TRAP_TRACE; 650 (*p->p_emul->e_trapsignal)(l, &ksi); 651 } 652 break; 653 } 654 655 if ((type & T_USER) == 0) 656 return; 657 out: 658 userret(l); 659 return; 660 trapsignal: 661 SIGDEBUG(frame, &ksi, 0); 662 (*p->p_emul->e_trapsignal)(l, &ksi); 663 userret(l); 664 } 665 666 /* 667 * startlwp: start of a new LWP. 668 */ 669 void 670 startlwp(void *arg) 671 { 672 ucontext_t *uc = arg; 673 lwp_t *l = curlwp; 674 int error __diagused; 675 676 error = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 677 KASSERT(error == 0); 678 679 kmem_free(uc, sizeof(ucontext_t)); 680 userret(l); 681 } 682 683 #ifdef TRAP_SIGDEBUG 684 static void 685 frame_dump(const struct trapframe *tf, struct pcb *pcb) 686 { 687 688 printf("trapframe %p\n", tf); 689 printf("rip %#018lx rsp %#018lx rfl %#018lx\n", 690 tf->tf_rip, tf->tf_rsp, tf->tf_rflags); 691 printf("rdi %#018lx rsi %#018lx rdx %#018lx\n", 692 tf->tf_rdi, tf->tf_rsi, tf->tf_rdx); 693 printf("rcx %#018lx r8 %#018lx r9 %#018lx\n", 694 tf->tf_rcx, tf->tf_r8, tf->tf_r9); 695 printf("r10 %#018lx r11 %#018lx r12 %#018lx\n", 696 tf->tf_r10, tf->tf_r11, tf->tf_r12); 697 printf("r13 %#018lx r14 %#018lx r15 %#018lx\n", 698 tf->tf_r13, tf->tf_r14, tf->tf_r15); 699 printf("rbp %#018lx rbx %#018lx rax %#018lx\n", 700 tf->tf_rbp, tf->tf_rbx, tf->tf_rax); 701 printf("cs %#04lx ds %#04lx es %#04lx " 702 "fs %#04lx gs %#04lx ss %#04lx\n", 703 tf->tf_cs & 0xffff, tf->tf_ds & 0xffff, tf->tf_es & 0xffff, 704 tf->tf_fs & 0xffff, tf->tf_gs & 0xffff, tf->tf_ss & 0xffff); 705 printf("fsbase %#018lx gsbase %#018lx\n", pcb->pcb_fs, pcb->pcb_gs); 706 printf("\n"); 707 hexdump(printf, "Stack dump", tf, 256); 708 } 709 710 static void 711 sigdebug(const struct trapframe *tf, const ksiginfo_t *ksi, int e) 712 { 713 struct lwp *l = curlwp; 714 struct proc *p = l->l_proc; 715 716 printf("pid %d.%d (%s): signal %d code=%d (trap %#lx) " 717 "@rip %#lx addr %#lx error=%d\n", 718 p->p_pid, l->l_lid, p->p_comm, ksi->ksi_signo, ksi->ksi_code, 719 tf->tf_trapno, tf->tf_rip, rcr2(), e); 720 frame_dump(tf, lwp_getpcb(l)); 721 } 722 #endif 723
Indexes created Thu Sep 25 16:09:42 GMT 2025