1 /* 2 * Copyright (C) 2002- 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include <stdlib.h> 7 #include <unistd.h> 8 #include <sched.h> 9 #include <errno.h> 10 #include <string.h> 11 #include <sys/mman.h> 12 #include <sys/ptrace.h> 13 #include <sys/wait.h> 14 #include <asm/unistd.h> 15 #include "as-layout.h" 16 #include "chan_user.h" 17 #include "kern_constants.h" 18 #include "kern_util.h" 19 #include "mem.h" 20 #include "os.h" 21 #include "process.h" 22 #include "proc_mm.h" 23 #include "ptrace_user.h" 24 #include "registers.h" 25 #include "skas.h" 26 #include "skas_ptrace.h" 27 #include "user.h" 28 #include "sysdep/stub.h" 29 30 int is_skas_winch(int pid, int fd, void *data) 31 { 32 if (pid != getpgrp()) 33 return 0; 34 35 register_winch_irq(-1, fd, -1, data, 0); 36 return 1; 37 } 38 39 static int ptrace_dump_regs(int pid) 40 { 41 unsigned long regs[MAX_REG_NR]; 42 int i; 43 44 if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0) 45 return -errno; 46 47 printk(UM_KERN_ERR "Stub registers -\n"); 48 for (i = 0; i < ARRAY_SIZE(regs); i++) 49 printk(UM_KERN_ERR "\t%d - %lx\n", i, regs[i]); 50 51 return 0; 52 } 53 54 /* 55 * Signals that are OK to receive in the stub - we'll just continue it. 56 * SIGWINCH will happen when UML is inside a detached screen. 57 */ 58 #define STUB_SIG_MASK ((1 << SIGVTALRM) | (1 << SIGWINCH)) 59 60 /* Signals that the stub will finish with - anything else is an error */ 61 #define STUB_DONE_MASK (1 << SIGTRAP) 62 63 void wait_stub_done(int pid) 64 { 65 int n, status, err; 66 67 while (1) { 68 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); 69 if ((n < 0) || !WIFSTOPPED(status)) 70 goto bad_wait; 71 72 if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0) 73 break; 74 75 err = ptrace(PTRACE_CONT, pid, 0, 0); 76 if (err) { 77 printk(UM_KERN_ERR "wait_stub_done : continue failed, " 78 "errno = %d\n", errno); 79 fatal_sigsegv(); 80 } 81 } 82 83 if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0) 84 return; 85 86 bad_wait: 87 err = ptrace_dump_regs(pid); 88 if (err) 89 printk(UM_KERN_ERR "Failed to get registers from stub, " 90 "errno = %d\n", -err); 91 printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, " 92 "pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno, 93 status); 94 fatal_sigsegv(); 95 } 96 97 extern unsigned long current_stub_stack(void); 98 99 static void get_skas_faultinfo(int pid, struct faultinfo *fi) 100 { 101 int err; 102 103 if (ptrace_faultinfo) { 104 err = ptrace(PTRACE_FAULTINFO, pid, 0, fi); 105 if (err) { 106 printk(UM_KERN_ERR "get_skas_faultinfo - " 107 "PTRACE_FAULTINFO failed, errno = %d\n", errno); 108 fatal_sigsegv(); 109 } 110 111 /* Special handling for i386, which has different structs */ 112 if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo)) 113 memset((char *)fi + sizeof(struct ptrace_faultinfo), 0, 114 sizeof(struct faultinfo) - 115 sizeof(struct ptrace_faultinfo)); 116 } 117 else { 118 unsigned long fpregs[FP_SIZE]; 119 120 err = get_fp_registers(pid, fpregs); 121 if (err < 0) { 122 printk(UM_KERN_ERR "save_fp_registers returned %d\n", 123 err); 124 fatal_sigsegv(); 125 } 126 err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV); 127 if (err) { 128 printk(UM_KERN_ERR "Failed to continue stub, pid = %d, " 129 "errno = %d\n", pid, errno); 130 fatal_sigsegv(); 131 } 132 wait_stub_done(pid); 133 134 /* 135 * faultinfo is prepared by the stub-segv-handler at start of 136 * the stub stack page. We just have to copy it. 137 */ 138 memcpy(fi, (void *)current_stub_stack(), sizeof(*fi)); 139 140 err = put_fp_registers(pid, fpregs); 141 if (err < 0) { 142 printk(UM_KERN_ERR "put_fp_registers returned %d\n", 143 err); 144 fatal_sigsegv(); 145 } 146 } 147 } 148 149 static void handle_segv(int pid, struct uml_pt_regs * regs) 150 { 151 get_skas_faultinfo(pid, ®s->faultinfo); 152 segv(regs->faultinfo, 0, 1, NULL); 153 } 154 155 /* 156 * To use the same value of using_sysemu as the caller, ask it that value 157 * (in local_using_sysemu 158 */ 159 static void handle_trap(int pid, struct uml_pt_regs *regs, 160 int local_using_sysemu) 161 { 162 int err, status; 163 164 if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END)) 165 fatal_sigsegv(); 166 167 /* Mark this as a syscall */ 168 UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp); 169 170 if (!local_using_sysemu) 171 { 172 err = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET, 173 __NR_getpid); 174 if (err < 0) { 175 printk(UM_KERN_ERR "handle_trap - nullifying syscall " 176 "failed, errno = %d\n", errno); 177 fatal_sigsegv(); 178 } 179 180 err = ptrace(PTRACE_SYSCALL, pid, 0, 0); 181 if (err < 0) { 182 printk(UM_KERN_ERR "handle_trap - continuing to end of " 183 "syscall failed, errno = %d\n", errno); 184 fatal_sigsegv(); 185 } 186 187 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); 188 if ((err < 0) || !WIFSTOPPED(status) || 189 (WSTOPSIG(status) != SIGTRAP + 0x80)) { 190 err = ptrace_dump_regs(pid); 191 if (err) 192 printk(UM_KERN_ERR "Failed to get registers " 193 "from process, errno = %d\n", -err); 194 printk(UM_KERN_ERR "handle_trap - failed to wait at " 195 "end of syscall, errno = %d, status = %d\n", 196 errno, status); 197 fatal_sigsegv(); 198 } 199 } 200 201 handle_syscall(regs); 202 } 203 204 extern int __syscall_stub_start; 205 206 static int userspace_tramp(void *stack) 207 { 208 void *addr; 209 int err; 210 211 ptrace(PTRACE_TRACEME, 0, 0, 0); 212 213 signal(SIGTERM, SIG_DFL); 214 signal(SIGWINCH, SIG_IGN); 215 err = set_interval(); 216 if (err) { 217 printk(UM_KERN_ERR "userspace_tramp - setting timer failed, " 218 "errno = %d\n", err); 219 exit(1); 220 } 221 222 if (!proc_mm) { 223 /* 224 * This has a pte, but it can't be mapped in with the usual 225 * tlb_flush mechanism because this is part of that mechanism 226 */ 227 int fd; 228 unsigned long long offset; 229 fd = phys_mapping(to_phys(&__syscall_stub_start), &offset); 230 addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE, 231 PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset); 232 if (addr == MAP_FAILED) { 233 printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, " 234 "errno = %d\n", STUB_CODE, errno); 235 exit(1); 236 } 237 238 if (stack != NULL) { 239 fd = phys_mapping(to_phys(stack), &offset); 240 addr = mmap((void *) STUB_DATA, 241 UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, 242 MAP_FIXED | MAP_SHARED, fd, offset); 243 if (addr == MAP_FAILED) { 244 printk(UM_KERN_ERR "mapping segfault stack " 245 "at 0x%lx failed, errno = %d\n", 246 STUB_DATA, errno); 247 exit(1); 248 } 249 } 250 } 251 if (!ptrace_faultinfo && (stack != NULL)) { 252 struct sigaction sa; 253 254 unsigned long v = STUB_CODE + 255 (unsigned long) stub_segv_handler - 256 (unsigned long) &__syscall_stub_start; 257 258 set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE); 259 sigemptyset(&sa.sa_mask); 260 sa.sa_flags = SA_ONSTACK | SA_NODEFER; 261 sa.sa_handler = (void *) v; 262 sa.sa_restorer = NULL; 263 if (sigaction(SIGSEGV, &sa, NULL) < 0) { 264 printk(UM_KERN_ERR "userspace_tramp - setting SIGSEGV " 265 "handler failed - errno = %d\n", errno); 266 exit(1); 267 } 268 } 269 270 kill(os_getpid(), SIGSTOP); 271 return 0; 272 } 273 274 /* Each element set once, and only accessed by a single processor anyway */ 275 #undef NR_CPUS 276 #define NR_CPUS 1 277 int userspace_pid[NR_CPUS]; 278 279 int start_userspace(unsigned long stub_stack) 280 { 281 void *stack; 282 unsigned long sp; 283 int pid, status, n, flags, err; 284 285 stack = mmap(NULL, UM_KERN_PAGE_SIZE, 286 PROT_READ | PROT_WRITE | PROT_EXEC, 287 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 288 if (stack == MAP_FAILED) { 289 err = -errno; 290 printk(UM_KERN_ERR "start_userspace : mmap failed, " 291 "errno = %d\n", errno); 292 return err; 293 } 294 295 sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *); 296 297 flags = CLONE_FILES; 298 if (proc_mm) 299 flags |= CLONE_VM; 300 else 301 flags |= SIGCHLD; 302 303 pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack); 304 if (pid < 0) { 305 err = -errno; 306 printk(UM_KERN_ERR "start_userspace : clone failed, " 307 "errno = %d\n", errno); 308 return err; 309 } 310 311 do { 312 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); 313 if (n < 0) { 314 err = -errno; 315 printk(UM_KERN_ERR "start_userspace : wait failed, " 316 "errno = %d\n", errno); 317 goto out_kill; 318 } 319 } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM)); 320 321 if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) { 322 err = -EINVAL; 323 printk(UM_KERN_ERR "start_userspace : expected SIGSTOP, got " 324 "status = %d\n", status); 325 goto out_kill; 326 } 327 328 if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, 329 (void *) PTRACE_O_TRACESYSGOOD) < 0) { 330 err = -errno; 331 printk(UM_KERN_ERR "start_userspace : PTRACE_OLDSETOPTIONS " 332 "failed, errno = %d\n", errno); 333 goto out_kill; 334 } 335 336 if (munmap(stack, UM_KERN_PAGE_SIZE) < 0) { 337 err = -errno; 338 printk(UM_KERN_ERR "start_userspace : munmap failed, " 339 "errno = %d\n", errno); 340 goto out_kill; 341 } 342 343 return pid; 344 345 out_kill: 346 os_kill_ptraced_process(pid, 1); 347 return err; 348 } 349 350 void userspace(struct uml_pt_regs *regs) 351 { 352 struct itimerval timer; 353 unsigned long long nsecs, now; 354 int err, status, op, pid = userspace_pid[0]; 355 /* To prevent races if using_sysemu changes under us.*/ 356 int local_using_sysemu; 357 358 if (getitimer(ITIMER_VIRTUAL, &timer)) 359 printk(UM_KERN_ERR "Failed to get itimer, errno = %d\n", errno); 360 nsecs = timer.it_value.tv_sec * UM_NSEC_PER_SEC + 361 timer.it_value.tv_usec * UM_NSEC_PER_USEC; 362 nsecs += os_nsecs(); 363 364 while (1) { 365 /* 366 * This can legitimately fail if the process loads a 367 * bogus value into a segment register. It will 368 * segfault and PTRACE_GETREGS will read that value 369 * out of the process. However, PTRACE_SETREGS will 370 * fail. In this case, there is nothing to do but 371 * just kill the process. 372 */ 373 if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp)) 374 fatal_sigsegv(); 375 376 if (put_fp_registers(pid, regs->fp)) 377 fatal_sigsegv(); 378 379 /* Now we set local_using_sysemu to be used for one loop */ 380 local_using_sysemu = get_using_sysemu(); 381 382 op = SELECT_PTRACE_OPERATION(local_using_sysemu, 383 singlestepping(NULL)); 384 385 if (ptrace(op, pid, 0, 0)) { 386 printk(UM_KERN_ERR "userspace - ptrace continue " 387 "failed, op = %d, errno = %d\n", op, errno); 388 fatal_sigsegv(); 389 } 390 391 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); 392 if (err < 0) { 393 printk(UM_KERN_ERR "userspace - wait failed, " 394 "errno = %d\n", errno); 395 fatal_sigsegv(); 396 } 397 398 regs->is_user = 1; 399 if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp)) { 400 printk(UM_KERN_ERR "userspace - PTRACE_GETREGS failed, " 401 "errno = %d\n", errno); 402 fatal_sigsegv(); 403 } 404 405 if (get_fp_registers(pid, regs->fp)) { 406 printk(UM_KERN_ERR "userspace - get_fp_registers failed, " 407 "errno = %d\n", errno); 408 fatal_sigsegv(); 409 } 410 411 UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */ 412 413 if (WIFSTOPPED(status)) { 414 int sig = WSTOPSIG(status); 415 switch (sig) { 416 case SIGSEGV: 417 if (PTRACE_FULL_FAULTINFO || 418 !ptrace_faultinfo) { 419 get_skas_faultinfo(pid, 420 ®s->faultinfo); 421 (*sig_info[SIGSEGV])(SIGSEGV, regs); 422 } 423 else handle_segv(pid, regs); 424 break; 425 case SIGTRAP + 0x80: 426 handle_trap(pid, regs, local_using_sysemu); 427 break; 428 case SIGTRAP: 429 relay_signal(SIGTRAP, regs); 430 break; 431 case SIGVTALRM: 432 now = os_nsecs(); 433 if (now < nsecs) 434 break; 435 block_signals(); 436 (*sig_info[sig])(sig, regs); 437 unblock_signals(); 438 nsecs = timer.it_value.tv_sec * 439 UM_NSEC_PER_SEC + 440 timer.it_value.tv_usec * 441 UM_NSEC_PER_USEC; 442 nsecs += os_nsecs(); 443 break; 444 case SIGIO: 445 case SIGILL: 446 case SIGBUS: 447 case SIGFPE: 448 case SIGWINCH: 449 block_signals(); 450 (*sig_info[sig])(sig, regs); 451 unblock_signals(); 452 break; 453 default: 454 printk(UM_KERN_ERR "userspace - child stopped " 455 "with signal %d\n", sig); 456 fatal_sigsegv(); 457 } 458 pid = userspace_pid[0]; 459 interrupt_end(); 460 461 /* Avoid -ERESTARTSYS handling in host */ 462 if (PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET) 463 PT_SYSCALL_NR(regs->gp) = -1; 464 } 465 } 466 } 467 468 static unsigned long thread_regs[MAX_REG_NR]; 469 static unsigned long thread_fp_regs[FP_SIZE]; 470 471 static int __init init_thread_regs(void) 472 { 473 get_safe_registers(thread_regs, thread_fp_regs); 474 /* Set parent's instruction pointer to start of clone-stub */ 475 thread_regs[REGS_IP_INDEX] = STUB_CODE + 476 (unsigned long) stub_clone_handler - 477 (unsigned long) &__syscall_stub_start; 478 thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE - 479 sizeof(void *); 480 #ifdef __SIGNAL_FRAMESIZE 481 thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE; 482 #endif 483 return 0; 484 } 485 486 __initcall(init_thread_regs); 487 488 int copy_context_skas0(unsigned long new_stack, int pid) 489 { 490 struct timeval tv = { .tv_sec = 0, .tv_usec = UM_USEC_PER_SEC / UM_HZ }; 491 int err; 492 unsigned long current_stack = current_stub_stack(); 493 struct stub_data *data = (struct stub_data *) current_stack; 494 struct stub_data *child_data = (struct stub_data *) new_stack; 495 unsigned long long new_offset; 496 int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset); 497 498 /* 499 * prepare offset and fd of child's stack as argument for parent's 500 * and child's mmap2 calls 501 */ 502 *data = ((struct stub_data) { .offset = MMAP_OFFSET(new_offset), 503 .fd = new_fd, 504 .timer = ((struct itimerval) 505 { .it_value = tv, 506 .it_interval = tv }) }); 507 508 err = ptrace_setregs(pid, thread_regs); 509 if (err < 0) { 510 err = -errno; 511 printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_SETREGS " 512 "failed, pid = %d, errno = %d\n", pid, -err); 513 return err; 514 } 515 516 err = put_fp_registers(pid, thread_fp_regs); 517 if (err < 0) { 518 printk(UM_KERN_ERR "copy_context_skas0 : put_fp_registers " 519 "failed, pid = %d, err = %d\n", pid, err); 520 return err; 521 } 522 523 /* set a well known return code for detection of child write failure */ 524 child_data->err = 12345678; 525 526 /* 527 * Wait, until parent has finished its work: read child's pid from 528 * parent's stack, and check, if bad result. 529 */ 530 err = ptrace(PTRACE_CONT, pid, 0, 0); 531 if (err) { 532 err = -errno; 533 printk(UM_KERN_ERR "Failed to continue new process, pid = %d, " 534 "errno = %d\n", pid, errno); 535 return err; 536 } 537 538 wait_stub_done(pid); 539 540 pid = data->err; 541 if (pid < 0) { 542 printk(UM_KERN_ERR "copy_context_skas0 - stub-parent reports " 543 "error %d\n", -pid); 544 return pid; 545 } 546 547 /* 548 * Wait, until child has finished too: read child's result from 549 * child's stack and check it. 550 */ 551 wait_stub_done(pid); 552 if (child_data->err != STUB_DATA) { 553 printk(UM_KERN_ERR "copy_context_skas0 - stub-child reports " 554 "error %ld\n", child_data->err); 555 err = child_data->err; 556 goto out_kill; 557 } 558 559 if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, 560 (void *)PTRACE_O_TRACESYSGOOD) < 0) { 561 err = -errno; 562 printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_OLDSETOPTIONS " 563 "failed, errno = %d\n", errno); 564 goto out_kill; 565 } 566 567 return pid; 568 569 out_kill: 570 os_kill_ptraced_process(pid, 1); 571 return err; 572 } 573 574 /* 575 * This is used only, if stub pages are needed, while proc_mm is 576 * available. Opening /proc/mm creates a new mm_context, which lacks 577 * the stub-pages. Thus, we map them using /proc/mm-fd 578 */ 579 int map_stub_pages(int fd, unsigned long code, unsigned long data, 580 unsigned long stack) 581 { 582 struct proc_mm_op mmop; 583 int n; 584 unsigned long long code_offset; 585 int code_fd = phys_mapping(to_phys((void *) &__syscall_stub_start), 586 &code_offset); 587 588 mmop = ((struct proc_mm_op) { .op = MM_MMAP, 589 .u = 590 { .mmap = 591 { .addr = code, 592 .len = UM_KERN_PAGE_SIZE, 593 .prot = PROT_EXEC, 594 .flags = MAP_FIXED | MAP_PRIVATE, 595 .fd = code_fd, 596 .offset = code_offset 597 } } }); 598 CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop))); 599 if (n != sizeof(mmop)) { 600 n = errno; 601 printk(UM_KERN_ERR "mmap args - addr = 0x%lx, fd = %d, " 602 "offset = %llx\n", code, code_fd, 603 (unsigned long long) code_offset); 604 printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for code " 605 "failed, err = %d\n", n); 606 return -n; 607 } 608 609 if (stack) { 610 unsigned long long map_offset; 611 int map_fd = phys_mapping(to_phys((void *)stack), &map_offset); 612 mmop = ((struct proc_mm_op) 613 { .op = MM_MMAP, 614 .u = 615 { .mmap = 616 { .addr = data, 617 .len = UM_KERN_PAGE_SIZE, 618 .prot = PROT_READ | PROT_WRITE, 619 .flags = MAP_FIXED | MAP_SHARED, 620 .fd = map_fd, 621 .offset = map_offset 622 } } }); 623 CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop))); 624 if (n != sizeof(mmop)) { 625 n = errno; 626 printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for " 627 "data failed, err = %d\n", n); 628 return -n; 629 } 630 } 631 632 return 0; 633 } 634 635 void new_thread(void *stack, jmp_buf *buf, void (*handler)(void)) 636 { 637 (*buf)[0].JB_IP = (unsigned long) handler; 638 (*buf)[0].JB_SP = (unsigned long) stack + UM_THREAD_SIZE - 639 sizeof(void *); 640 } 641 642 #define INIT_JMP_NEW_THREAD 0 643 #define INIT_JMP_CALLBACK 1 644 #define INIT_JMP_HALT 2 645 #define INIT_JMP_REBOOT 3 646 647 void switch_threads(jmp_buf *me, jmp_buf *you) 648 { 649 if (UML_SETJMP(me) == 0) 650 UML_LONGJMP(you, 1); 651 } 652 653 static jmp_buf initial_jmpbuf; 654 655 /* XXX Make these percpu */ 656 static void (*cb_proc)(void *arg); 657 static void *cb_arg; 658 static jmp_buf *cb_back; 659 660 int start_idle_thread(void *stack, jmp_buf *switch_buf) 661 { 662 int n; 663 664 set_handler(SIGWINCH, (__sighandler_t) sig_handler, 665 SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGVTALRM, -1); 666 667 /* 668 * Can't use UML_SETJMP or UML_LONGJMP here because they save 669 * and restore signals, with the possible side-effect of 670 * trying to handle any signals which came when they were 671 * blocked, which can't be done on this stack. 672 * Signals must be blocked when jumping back here and restored 673 * after returning to the jumper. 674 */ 675 n = setjmp(initial_jmpbuf); 676 switch (n) { 677 case INIT_JMP_NEW_THREAD: 678 (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler; 679 (*switch_buf)[0].JB_SP = (unsigned long) stack + 680 UM_THREAD_SIZE - sizeof(void *); 681 break; 682 case INIT_JMP_CALLBACK: 683 (*cb_proc)(cb_arg); 684 longjmp(*cb_back, 1); 685 break; 686 case INIT_JMP_HALT: 687 kmalloc_ok = 0; 688 return 0; 689 case INIT_JMP_REBOOT: 690 kmalloc_ok = 0; 691 return 1; 692 default: 693 printk(UM_KERN_ERR "Bad sigsetjmp return in " 694 "start_idle_thread - %d\n", n); 695 fatal_sigsegv(); 696 } 697 longjmp(*switch_buf, 1); 698 } 699 700 void initial_thread_cb_skas(void (*proc)(void *), void *arg) 701 { 702 jmp_buf here; 703 704 cb_proc = proc; 705 cb_arg = arg; 706 cb_back = &here; 707 708 block_signals(); 709 if (UML_SETJMP(&here) == 0) 710 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK); 711 unblock_signals(); 712 713 cb_proc = NULL; 714 cb_arg = NULL; 715 cb_back = NULL; 716 } 717 718 void halt_skas(void) 719 { 720 block_signals(); 721 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT); 722 } 723 724 void reboot_skas(void) 725 { 726 block_signals(); 727 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT); 728 } 729 730 void __switch_mm(struct mm_id *mm_idp) 731 { 732 int err; 733 734 /* FIXME: need cpu pid in __switch_mm */ 735 if (proc_mm) { 736 err = ptrace(PTRACE_SWITCH_MM, userspace_pid[0], 0, 737 mm_idp->u.mm_fd); 738 if (err) { 739 printk(UM_KERN_ERR "__switch_mm - PTRACE_SWITCH_MM " 740 "failed, errno = %d\n", errno); 741 fatal_sigsegv(); 742 } 743 } 744 else userspace_pid[0] = mm_idp->u.pid; 745 } 746