1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 2 3 #include <linux/module.h> 4 #include <linux/reboot.h> 5 #include <linux/init.h> 6 #include <linux/pm.h> 7 #include <linux/efi.h> 8 #include <linux/dmi.h> 9 #include <linux/sched.h> 10 #include <linux/tboot.h> 11 #include <linux/delay.h> 12 #include <acpi/reboot.h> 13 #include <asm/io.h> 14 #include <asm/apic.h> 15 #include <asm/io_apic.h> 16 #include <asm/desc.h> 17 #include <asm/hpet.h> 18 #include <asm/pgtable.h> 19 #include <asm/proto.h> 20 #include <asm/reboot_fixups.h> 21 #include <asm/reboot.h> 22 #include <asm/pci_x86.h> 23 #include <asm/virtext.h> 24 #include <asm/cpu.h> 25 #include <asm/nmi.h> 26 #include <asm/smp.h> 27 28 #include <linux/ctype.h> 29 #include <linux/mc146818rtc.h> 30 #include <asm/realmode.h> 31 #include <asm/x86_init.h> 32 #include <asm/efi.h> 33 34 /* 35 * Power off function, if any 36 */ 37 void (*pm_power_off)(void); 38 EXPORT_SYMBOL(pm_power_off); 39 40 static const struct desc_ptr no_idt = {}; 41 42 /* 43 * This is set if we need to go through the 'emergency' path. 44 * When machine_emergency_restart() is called, we may be on 45 * an inconsistent state and won't be able to do a clean cleanup 46 */ 47 static int reboot_emergency; 48 49 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */ 50 bool port_cf9_safe = false; 51 52 /* 53 * Reboot options and system auto-detection code provided by 54 * Dell Inc. so their systems "just work". :-) 55 */ 56 57 /* 58 * Some machines require the "reboot=b" or "reboot=k" commandline options, 59 * this quirk makes that automatic. 60 */ 61 static int __init set_bios_reboot(const struct dmi_system_id *d) 62 { 63 if (reboot_type != BOOT_BIOS) { 64 reboot_type = BOOT_BIOS; 65 pr_info("%s series board detected. Selecting %s-method for reboots.\n", 66 d->ident, "BIOS"); 67 } 68 return 0; 69 } 70 71 void __noreturn machine_real_restart(unsigned int type) 72 { 73 local_irq_disable(); 74 75 /* 76 * Write zero to CMOS register number 0x0f, which the BIOS POST 77 * routine will recognize as telling it to do a proper reboot. (Well 78 * that's what this book in front of me says -- it may only apply to 79 * the Phoenix BIOS though, it's not clear). At the same time, 80 * disable NMIs by setting the top bit in the CMOS address register, 81 * as we're about to do peculiar things to the CPU. I'm not sure if 82 * `outb_p' is needed instead of just `outb'. Use it to be on the 83 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) 84 */ 85 spin_lock(&rtc_lock); 86 CMOS_WRITE(0x00, 0x8f); 87 spin_unlock(&rtc_lock); 88 89 /* 90 * Switch back to the initial page table. 91 */ 92 #ifdef CONFIG_X86_32 93 load_cr3(initial_page_table); 94 #else 95 write_cr3(real_mode_header->trampoline_pgd); 96 #endif 97 98 /* Jump to the identity-mapped low memory code */ 99 #ifdef CONFIG_X86_32 100 asm volatile("jmpl *%0" : : 101 "rm" (real_mode_header->machine_real_restart_asm), 102 "a" (type)); 103 #else 104 asm volatile("ljmpl *%0" : : 105 "m" (real_mode_header->machine_real_restart_asm), 106 "D" (type)); 107 #endif 108 unreachable(); 109 } 110 #ifdef CONFIG_APM_MODULE 111 EXPORT_SYMBOL(machine_real_restart); 112 #endif 113 114 /* 115 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot 116 */ 117 static int __init set_pci_reboot(const struct dmi_system_id *d) 118 { 119 if (reboot_type != BOOT_CF9_FORCE) { 120 reboot_type = BOOT_CF9_FORCE; 121 pr_info("%s series board detected. Selecting %s-method for reboots.\n", 122 d->ident, "PCI"); 123 } 124 return 0; 125 } 126 127 static int __init set_kbd_reboot(const struct dmi_system_id *d) 128 { 129 if (reboot_type != BOOT_KBD) { 130 reboot_type = BOOT_KBD; 131 pr_info("%s series board detected. Selecting %s-method for reboot.\n", 132 d->ident, "KBD"); 133 } 134 return 0; 135 } 136 137 /* 138 * This is a single dmi_table handling all reboot quirks. 139 */ 140 static struct dmi_system_id __initdata reboot_dmi_table[] = { 141 142 /* Acer */ 143 { /* Handle reboot issue on Acer Aspire one */ 144 .callback = set_kbd_reboot, 145 .ident = "Acer Aspire One A110", 146 .matches = { 147 DMI_MATCH(DMI_SYS_VENDOR, "Acer"), 148 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"), 149 }, 150 }, 151 152 /* Apple */ 153 { /* Handle problems with rebooting on Apple MacBook5 */ 154 .callback = set_pci_reboot, 155 .ident = "Apple MacBook5", 156 .matches = { 157 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 158 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"), 159 }, 160 }, 161 { /* Handle problems with rebooting on Apple MacBookPro5 */ 162 .callback = set_pci_reboot, 163 .ident = "Apple MacBookPro5", 164 .matches = { 165 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 166 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"), 167 }, 168 }, 169 { /* Handle problems with rebooting on Apple Macmini3,1 */ 170 .callback = set_pci_reboot, 171 .ident = "Apple Macmini3,1", 172 .matches = { 173 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 174 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"), 175 }, 176 }, 177 { /* Handle problems with rebooting on the iMac9,1. */ 178 .callback = set_pci_reboot, 179 .ident = "Apple iMac9,1", 180 .matches = { 181 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 182 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"), 183 }, 184 }, 185 186 /* ASRock */ 187 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */ 188 .callback = set_pci_reboot, 189 .ident = "ASRock Q1900DC-ITX", 190 .matches = { 191 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"), 192 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"), 193 }, 194 }, 195 196 /* ASUS */ 197 { /* Handle problems with rebooting on ASUS P4S800 */ 198 .callback = set_bios_reboot, 199 .ident = "ASUS P4S800", 200 .matches = { 201 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), 202 DMI_MATCH(DMI_BOARD_NAME, "P4S800"), 203 }, 204 }, 205 206 /* Certec */ 207 { /* Handle problems with rebooting on Certec BPC600 */ 208 .callback = set_pci_reboot, 209 .ident = "Certec BPC600", 210 .matches = { 211 DMI_MATCH(DMI_SYS_VENDOR, "Certec"), 212 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"), 213 }, 214 }, 215 216 /* Dell */ 217 { /* Handle problems with rebooting on Dell DXP061 */ 218 .callback = set_bios_reboot, 219 .ident = "Dell DXP061", 220 .matches = { 221 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 222 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"), 223 }, 224 }, 225 { /* Handle problems with rebooting on Dell E520's */ 226 .callback = set_bios_reboot, 227 .ident = "Dell E520", 228 .matches = { 229 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 230 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"), 231 }, 232 }, 233 { /* Handle problems with rebooting on the Latitude E5410. */ 234 .callback = set_pci_reboot, 235 .ident = "Dell Latitude E5410", 236 .matches = { 237 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 238 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"), 239 }, 240 }, 241 { /* Handle problems with rebooting on the Latitude E5420. */ 242 .callback = set_pci_reboot, 243 .ident = "Dell Latitude E5420", 244 .matches = { 245 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 246 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"), 247 }, 248 }, 249 { /* Handle problems with rebooting on the Latitude E6320. */ 250 .callback = set_pci_reboot, 251 .ident = "Dell Latitude E6320", 252 .matches = { 253 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 254 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"), 255 }, 256 }, 257 { /* Handle problems with rebooting on the Latitude E6420. */ 258 .callback = set_pci_reboot, 259 .ident = "Dell Latitude E6420", 260 .matches = { 261 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 262 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"), 263 }, 264 }, 265 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */ 266 .callback = set_bios_reboot, 267 .ident = "Dell OptiPlex 330", 268 .matches = { 269 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 270 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"), 271 DMI_MATCH(DMI_BOARD_NAME, "0KP561"), 272 }, 273 }, 274 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */ 275 .callback = set_bios_reboot, 276 .ident = "Dell OptiPlex 360", 277 .matches = { 278 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 279 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"), 280 DMI_MATCH(DMI_BOARD_NAME, "0T656F"), 281 }, 282 }, 283 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */ 284 .callback = set_bios_reboot, 285 .ident = "Dell OptiPlex 745", 286 .matches = { 287 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 288 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 289 }, 290 }, 291 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */ 292 .callback = set_bios_reboot, 293 .ident = "Dell OptiPlex 745", 294 .matches = { 295 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 296 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 297 DMI_MATCH(DMI_BOARD_NAME, "0MM599"), 298 }, 299 }, 300 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ 301 .callback = set_bios_reboot, 302 .ident = "Dell OptiPlex 745", 303 .matches = { 304 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 305 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 306 DMI_MATCH(DMI_BOARD_NAME, "0KW626"), 307 }, 308 }, 309 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */ 310 .callback = set_bios_reboot, 311 .ident = "Dell OptiPlex 760", 312 .matches = { 313 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 314 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"), 315 DMI_MATCH(DMI_BOARD_NAME, "0G919G"), 316 }, 317 }, 318 { /* Handle problems with rebooting on the OptiPlex 990. */ 319 .callback = set_pci_reboot, 320 .ident = "Dell OptiPlex 990", 321 .matches = { 322 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 323 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"), 324 }, 325 }, 326 { /* Handle problems with rebooting on Dell 300's */ 327 .callback = set_bios_reboot, 328 .ident = "Dell PowerEdge 300", 329 .matches = { 330 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 331 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), 332 }, 333 }, 334 { /* Handle problems with rebooting on Dell 1300's */ 335 .callback = set_bios_reboot, 336 .ident = "Dell PowerEdge 1300", 337 .matches = { 338 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 339 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), 340 }, 341 }, 342 { /* Handle problems with rebooting on Dell 2400's */ 343 .callback = set_bios_reboot, 344 .ident = "Dell PowerEdge 2400", 345 .matches = { 346 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 347 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), 348 }, 349 }, 350 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */ 351 .callback = set_pci_reboot, 352 .ident = "Dell PowerEdge C6100", 353 .matches = { 354 DMI_MATCH(DMI_SYS_VENDOR, "Dell"), 355 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"), 356 }, 357 }, 358 { /* Handle problems with rebooting on the Precision M6600. */ 359 .callback = set_pci_reboot, 360 .ident = "Dell Precision M6600", 361 .matches = { 362 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 363 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"), 364 }, 365 }, 366 { /* Handle problems with rebooting on Dell T5400's */ 367 .callback = set_bios_reboot, 368 .ident = "Dell Precision T5400", 369 .matches = { 370 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 371 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"), 372 }, 373 }, 374 { /* Handle problems with rebooting on Dell T7400's */ 375 .callback = set_bios_reboot, 376 .ident = "Dell Precision T7400", 377 .matches = { 378 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 379 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"), 380 }, 381 }, 382 { /* Handle problems with rebooting on Dell XPS710 */ 383 .callback = set_bios_reboot, 384 .ident = "Dell XPS710", 385 .matches = { 386 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 387 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"), 388 }, 389 }, 390 391 /* Hewlett-Packard */ 392 { /* Handle problems with rebooting on HP laptops */ 393 .callback = set_bios_reboot, 394 .ident = "HP Compaq Laptop", 395 .matches = { 396 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 397 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"), 398 }, 399 }, 400 401 /* Sony */ 402 { /* Handle problems with rebooting on Sony VGN-Z540N */ 403 .callback = set_bios_reboot, 404 .ident = "Sony VGN-Z540N", 405 .matches = { 406 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"), 407 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"), 408 }, 409 }, 410 411 { } 412 }; 413 414 static int __init reboot_init(void) 415 { 416 int rv; 417 418 /* 419 * Only do the DMI check if reboot_type hasn't been overridden 420 * on the command line 421 */ 422 if (!reboot_default) 423 return 0; 424 425 /* 426 * The DMI quirks table takes precedence. If no quirks entry 427 * matches and the ACPI Hardware Reduced bit is set, force EFI 428 * reboot. 429 */ 430 rv = dmi_check_system(reboot_dmi_table); 431 432 if (!rv && efi_reboot_required()) 433 reboot_type = BOOT_EFI; 434 435 return 0; 436 } 437 core_initcall(reboot_init); 438 439 static inline void kb_wait(void) 440 { 441 int i; 442 443 for (i = 0; i < 0x10000; i++) { 444 if ((inb(0x64) & 0x02) == 0) 445 break; 446 udelay(2); 447 } 448 } 449 450 static void vmxoff_nmi(int cpu, struct pt_regs *regs) 451 { 452 cpu_emergency_vmxoff(); 453 } 454 455 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */ 456 static void emergency_vmx_disable_all(void) 457 { 458 /* Just make sure we won't change CPUs while doing this */ 459 local_irq_disable(); 460 461 /* 462 * We need to disable VMX on all CPUs before rebooting, otherwise 463 * we risk hanging up the machine, because the CPU ignore INIT 464 * signals when VMX is enabled. 465 * 466 * We can't take any locks and we may be on an inconsistent 467 * state, so we use NMIs as IPIs to tell the other CPUs to disable 468 * VMX and halt. 469 * 470 * For safety, we will avoid running the nmi_shootdown_cpus() 471 * stuff unnecessarily, but we don't have a way to check 472 * if other CPUs have VMX enabled. So we will call it only if the 473 * CPU we are running on has VMX enabled. 474 * 475 * We will miss cases where VMX is not enabled on all CPUs. This 476 * shouldn't do much harm because KVM always enable VMX on all 477 * CPUs anyway. But we can miss it on the small window where KVM 478 * is still enabling VMX. 479 */ 480 if (cpu_has_vmx() && cpu_vmx_enabled()) { 481 /* Disable VMX on this CPU. */ 482 cpu_vmxoff(); 483 484 /* Halt and disable VMX on the other CPUs */ 485 nmi_shootdown_cpus(vmxoff_nmi); 486 487 } 488 } 489 490 491 void __attribute__((weak)) mach_reboot_fixups(void) 492 { 493 } 494 495 /* 496 * To the best of our knowledge Windows compatible x86 hardware expects 497 * the following on reboot: 498 * 499 * 1) If the FADT has the ACPI reboot register flag set, try it 500 * 2) If still alive, write to the keyboard controller 501 * 3) If still alive, write to the ACPI reboot register again 502 * 4) If still alive, write to the keyboard controller again 503 * 5) If still alive, call the EFI runtime service to reboot 504 * 6) If no EFI runtime service, call the BIOS to do a reboot 505 * 506 * We default to following the same pattern. We also have 507 * two other reboot methods: 'triple fault' and 'PCI', which 508 * can be triggered via the reboot= kernel boot option or 509 * via quirks. 510 * 511 * This means that this function can never return, it can misbehave 512 * by not rebooting properly and hanging. 513 */ 514 static void native_machine_emergency_restart(void) 515 { 516 int i; 517 int attempt = 0; 518 int orig_reboot_type = reboot_type; 519 unsigned short mode; 520 521 if (reboot_emergency) 522 emergency_vmx_disable_all(); 523 524 tboot_shutdown(TB_SHUTDOWN_REBOOT); 525 526 /* Tell the BIOS if we want cold or warm reboot */ 527 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0; 528 *((unsigned short *)__va(0x472)) = mode; 529 530 for (;;) { 531 /* Could also try the reset bit in the Hammer NB */ 532 switch (reboot_type) { 533 case BOOT_ACPI: 534 acpi_reboot(); 535 reboot_type = BOOT_KBD; 536 break; 537 538 case BOOT_KBD: 539 mach_reboot_fixups(); /* For board specific fixups */ 540 541 for (i = 0; i < 10; i++) { 542 kb_wait(); 543 udelay(50); 544 outb(0xfe, 0x64); /* Pulse reset low */ 545 udelay(50); 546 } 547 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) { 548 attempt = 1; 549 reboot_type = BOOT_ACPI; 550 } else { 551 reboot_type = BOOT_EFI; 552 } 553 break; 554 555 case BOOT_EFI: 556 efi_reboot(reboot_mode, NULL); 557 reboot_type = BOOT_BIOS; 558 break; 559 560 case BOOT_BIOS: 561 machine_real_restart(MRR_BIOS); 562 563 /* We're probably dead after this, but... */ 564 reboot_type = BOOT_CF9_SAFE; 565 break; 566 567 case BOOT_CF9_FORCE: 568 port_cf9_safe = true; 569 /* Fall through */ 570 571 case BOOT_CF9_SAFE: 572 if (port_cf9_safe) { 573 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E; 574 u8 cf9 = inb(0xcf9) & ~reboot_code; 575 outb(cf9|2, 0xcf9); /* Request hard reset */ 576 udelay(50); 577 /* Actually do the reset */ 578 outb(cf9|reboot_code, 0xcf9); 579 udelay(50); 580 } 581 reboot_type = BOOT_TRIPLE; 582 break; 583 584 case BOOT_TRIPLE: 585 load_idt(&no_idt); 586 __asm__ __volatile__("int3"); 587 588 /* We're probably dead after this, but... */ 589 reboot_type = BOOT_KBD; 590 break; 591 } 592 } 593 } 594 595 void native_machine_shutdown(void) 596 { 597 /* Stop the cpus and apics */ 598 #ifdef CONFIG_X86_IO_APIC 599 /* 600 * Disabling IO APIC before local APIC is a workaround for 601 * erratum AVR31 in "Intel Atom Processor C2000 Product Family 602 * Specification Update". In this situation, interrupts that target 603 * a Logical Processor whose Local APIC is either in the process of 604 * being hardware disabled or software disabled are neither delivered 605 * nor discarded. When this erratum occurs, the processor may hang. 606 * 607 * Even without the erratum, it still makes sense to quiet IO APIC 608 * before disabling Local APIC. 609 */ 610 disable_IO_APIC(); 611 #endif 612 613 #ifdef CONFIG_SMP 614 /* 615 * Stop all of the others. Also disable the local irq to 616 * not receive the per-cpu timer interrupt which may trigger 617 * scheduler's load balance. 618 */ 619 local_irq_disable(); 620 stop_other_cpus(); 621 #endif 622 623 lapic_shutdown(); 624 625 #ifdef CONFIG_HPET_TIMER 626 hpet_disable(); 627 #endif 628 629 #ifdef CONFIG_X86_64 630 x86_platform.iommu_shutdown(); 631 #endif 632 } 633 634 static void __machine_emergency_restart(int emergency) 635 { 636 reboot_emergency = emergency; 637 machine_ops.emergency_restart(); 638 } 639 640 static void native_machine_restart(char *__unused) 641 { 642 pr_notice("machine restart\n"); 643 644 if (!reboot_force) 645 machine_shutdown(); 646 __machine_emergency_restart(0); 647 } 648 649 static void native_machine_halt(void) 650 { 651 /* Stop other cpus and apics */ 652 machine_shutdown(); 653 654 tboot_shutdown(TB_SHUTDOWN_HALT); 655 656 stop_this_cpu(NULL); 657 } 658 659 static void native_machine_power_off(void) 660 { 661 if (pm_power_off) { 662 if (!reboot_force) 663 machine_shutdown(); 664 pm_power_off(); 665 } 666 /* A fallback in case there is no PM info available */ 667 tboot_shutdown(TB_SHUTDOWN_HALT); 668 } 669 670 struct machine_ops machine_ops = { 671 .power_off = native_machine_power_off, 672 .shutdown = native_machine_shutdown, 673 .emergency_restart = native_machine_emergency_restart, 674 .restart = native_machine_restart, 675 .halt = native_machine_halt, 676 #ifdef CONFIG_KEXEC 677 .crash_shutdown = native_machine_crash_shutdown, 678 #endif 679 }; 680 681 void machine_power_off(void) 682 { 683 machine_ops.power_off(); 684 } 685 686 void machine_shutdown(void) 687 { 688 machine_ops.shutdown(); 689 } 690 691 void machine_emergency_restart(void) 692 { 693 __machine_emergency_restart(1); 694 } 695 696 void machine_restart(char *cmd) 697 { 698 machine_ops.restart(cmd); 699 } 700 701 void machine_halt(void) 702 { 703 machine_ops.halt(); 704 } 705 706 #ifdef CONFIG_KEXEC 707 void machine_crash_shutdown(struct pt_regs *regs) 708 { 709 machine_ops.crash_shutdown(regs); 710 } 711 #endif 712 713 714 #if defined(CONFIG_SMP) 715 716 /* This keeps a track of which one is crashing cpu. */ 717 static int crashing_cpu; 718 static nmi_shootdown_cb shootdown_callback; 719 720 static atomic_t waiting_for_crash_ipi; 721 722 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) 723 { 724 int cpu; 725 726 cpu = raw_smp_processor_id(); 727 728 /* 729 * Don't do anything if this handler is invoked on crashing cpu. 730 * Otherwise, system will completely hang. Crashing cpu can get 731 * an NMI if system was initially booted with nmi_watchdog parameter. 732 */ 733 if (cpu == crashing_cpu) 734 return NMI_HANDLED; 735 local_irq_disable(); 736 737 shootdown_callback(cpu, regs); 738 739 atomic_dec(&waiting_for_crash_ipi); 740 /* Assume hlt works */ 741 halt(); 742 for (;;) 743 cpu_relax(); 744 745 return NMI_HANDLED; 746 } 747 748 static void smp_send_nmi_allbutself(void) 749 { 750 apic->send_IPI_allbutself(NMI_VECTOR); 751 } 752 753 /* 754 * Halt all other CPUs, calling the specified function on each of them 755 * 756 * This function can be used to halt all other CPUs on crash 757 * or emergency reboot time. The function passed as parameter 758 * will be called inside a NMI handler on all CPUs. 759 */ 760 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 761 { 762 unsigned long msecs; 763 local_irq_disable(); 764 765 /* Make a note of crashing cpu. Will be used in NMI callback. */ 766 crashing_cpu = safe_smp_processor_id(); 767 768 shootdown_callback = callback; 769 770 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); 771 /* Would it be better to replace the trap vector here? */ 772 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback, 773 NMI_FLAG_FIRST, "crash")) 774 return; /* Return what? */ 775 /* 776 * Ensure the new callback function is set before sending 777 * out the NMI 778 */ 779 wmb(); 780 781 smp_send_nmi_allbutself(); 782 783 msecs = 1000; /* Wait at most a second for the other cpus to stop */ 784 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { 785 mdelay(1); 786 msecs--; 787 } 788 789 /* Leave the nmi callback set */ 790 } 791 #else /* !CONFIG_SMP */ 792 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 793 { 794 /* No other CPUs to shoot down */ 795 } 796 #endif 797