1 #include <linux/module.h> 2 #include <linux/reboot.h> 3 #include <linux/init.h> 4 #include <linux/pm.h> 5 #include <linux/efi.h> 6 #include <linux/dmi.h> 7 #include <linux/sched.h> 8 #include <linux/tboot.h> 9 #include <acpi/reboot.h> 10 #include <asm/io.h> 11 #include <asm/apic.h> 12 #include <asm/desc.h> 13 #include <asm/hpet.h> 14 #include <asm/pgtable.h> 15 #include <asm/proto.h> 16 #include <asm/reboot_fixups.h> 17 #include <asm/reboot.h> 18 #include <asm/pci_x86.h> 19 #include <asm/virtext.h> 20 #include <asm/cpu.h> 21 22 #ifdef CONFIG_X86_32 23 # include <linux/ctype.h> 24 # include <linux/mc146818rtc.h> 25 #else 26 # include <asm/x86_init.h> 27 #endif 28 29 /* 30 * Power off function, if any 31 */ 32 void (*pm_power_off)(void); 33 EXPORT_SYMBOL(pm_power_off); 34 35 static const struct desc_ptr no_idt = {}; 36 static int reboot_mode; 37 enum reboot_type reboot_type = BOOT_KBD; 38 int reboot_force; 39 40 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP) 41 static int reboot_cpu = -1; 42 #endif 43 44 /* This is set if we need to go through the 'emergency' path. 45 * When machine_emergency_restart() is called, we may be on 46 * an inconsistent state and won't be able to do a clean cleanup 47 */ 48 static int reboot_emergency; 49 50 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */ 51 bool port_cf9_safe = false; 52 53 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci] 54 warm Don't set the cold reboot flag 55 cold Set the cold reboot flag 56 bios Reboot by jumping through the BIOS (only for X86_32) 57 smp Reboot by executing reset on BSP or other CPU (only for X86_32) 58 triple Force a triple fault (init) 59 kbd Use the keyboard controller. cold reset (default) 60 acpi Use the RESET_REG in the FADT 61 efi Use efi reset_system runtime service 62 pci Use the so-called "PCI reset register", CF9 63 force Avoid anything that could hang. 64 */ 65 static int __init reboot_setup(char *str) 66 { 67 for (;;) { 68 switch (*str) { 69 case 'w': 70 reboot_mode = 0x1234; 71 break; 72 73 case 'c': 74 reboot_mode = 0; 75 break; 76 77 #ifdef CONFIG_X86_32 78 #ifdef CONFIG_SMP 79 case 's': 80 if (isdigit(*(str+1))) { 81 reboot_cpu = (int) (*(str+1) - '0'); 82 if (isdigit(*(str+2))) 83 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); 84 } 85 /* we will leave sorting out the final value 86 when we are ready to reboot, since we might not 87 have set up boot_cpu_id or smp_num_cpu */ 88 break; 89 #endif /* CONFIG_SMP */ 90 91 case 'b': 92 #endif 93 case 'a': 94 case 'k': 95 case 't': 96 case 'e': 97 case 'p': 98 reboot_type = *str; 99 break; 100 101 case 'f': 102 reboot_force = 1; 103 break; 104 } 105 106 str = strchr(str, ','); 107 if (str) 108 str++; 109 else 110 break; 111 } 112 return 1; 113 } 114 115 __setup("reboot=", reboot_setup); 116 117 118 #ifdef CONFIG_X86_32 119 /* 120 * Reboot options and system auto-detection code provided by 121 * Dell Inc. so their systems "just work". :-) 122 */ 123 124 /* 125 * Some machines require the "reboot=b" commandline option, 126 * this quirk makes that automatic. 127 */ 128 static int __init set_bios_reboot(const struct dmi_system_id *d) 129 { 130 if (reboot_type != BOOT_BIOS) { 131 reboot_type = BOOT_BIOS; 132 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident); 133 } 134 return 0; 135 } 136 137 static struct dmi_system_id __initdata reboot_dmi_table[] = { 138 { /* Handle problems with rebooting on Dell E520's */ 139 .callback = set_bios_reboot, 140 .ident = "Dell E520", 141 .matches = { 142 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 143 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"), 144 }, 145 }, 146 { /* Handle problems with rebooting on Dell 1300's */ 147 .callback = set_bios_reboot, 148 .ident = "Dell PowerEdge 1300", 149 .matches = { 150 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 151 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), 152 }, 153 }, 154 { /* Handle problems with rebooting on Dell 300's */ 155 .callback = set_bios_reboot, 156 .ident = "Dell PowerEdge 300", 157 .matches = { 158 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 159 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), 160 }, 161 }, 162 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/ 163 .callback = set_bios_reboot, 164 .ident = "Dell OptiPlex 745", 165 .matches = { 166 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 167 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 168 }, 169 }, 170 { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/ 171 .callback = set_bios_reboot, 172 .ident = "Dell OptiPlex 745", 173 .matches = { 174 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 175 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 176 DMI_MATCH(DMI_BOARD_NAME, "0MM599"), 177 }, 178 }, 179 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ 180 .callback = set_bios_reboot, 181 .ident = "Dell OptiPlex 745", 182 .matches = { 183 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 184 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 185 DMI_MATCH(DMI_BOARD_NAME, "0KW626"), 186 }, 187 }, 188 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */ 189 .callback = set_bios_reboot, 190 .ident = "Dell OptiPlex 330", 191 .matches = { 192 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 193 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"), 194 DMI_MATCH(DMI_BOARD_NAME, "0KP561"), 195 }, 196 }, 197 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */ 198 .callback = set_bios_reboot, 199 .ident = "Dell OptiPlex 360", 200 .matches = { 201 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 202 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"), 203 DMI_MATCH(DMI_BOARD_NAME, "0T656F"), 204 }, 205 }, 206 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/ 207 .callback = set_bios_reboot, 208 .ident = "Dell OptiPlex 760", 209 .matches = { 210 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 211 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"), 212 DMI_MATCH(DMI_BOARD_NAME, "0G919G"), 213 }, 214 }, 215 { /* Handle problems with rebooting on Dell 2400's */ 216 .callback = set_bios_reboot, 217 .ident = "Dell PowerEdge 2400", 218 .matches = { 219 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 220 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), 221 }, 222 }, 223 { /* Handle problems with rebooting on Dell T5400's */ 224 .callback = set_bios_reboot, 225 .ident = "Dell Precision T5400", 226 .matches = { 227 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 228 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"), 229 }, 230 }, 231 { /* Handle problems with rebooting on Dell T7400's */ 232 .callback = set_bios_reboot, 233 .ident = "Dell Precision T7400", 234 .matches = { 235 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 236 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"), 237 }, 238 }, 239 { /* Handle problems with rebooting on HP laptops */ 240 .callback = set_bios_reboot, 241 .ident = "HP Compaq Laptop", 242 .matches = { 243 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 244 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"), 245 }, 246 }, 247 { /* Handle problems with rebooting on Dell XPS710 */ 248 .callback = set_bios_reboot, 249 .ident = "Dell XPS710", 250 .matches = { 251 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 252 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"), 253 }, 254 }, 255 { /* Handle problems with rebooting on Dell DXP061 */ 256 .callback = set_bios_reboot, 257 .ident = "Dell DXP061", 258 .matches = { 259 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 260 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"), 261 }, 262 }, 263 { /* Handle problems with rebooting on Sony VGN-Z540N */ 264 .callback = set_bios_reboot, 265 .ident = "Sony VGN-Z540N", 266 .matches = { 267 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"), 268 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"), 269 }, 270 }, 271 { /* Handle problems with rebooting on CompuLab SBC-FITPC2 */ 272 .callback = set_bios_reboot, 273 .ident = "CompuLab SBC-FITPC2", 274 .matches = { 275 DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"), 276 DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"), 277 }, 278 }, 279 { /* Handle problems with rebooting on ASUS P4S800 */ 280 .callback = set_bios_reboot, 281 .ident = "ASUS P4S800", 282 .matches = { 283 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), 284 DMI_MATCH(DMI_BOARD_NAME, "P4S800"), 285 }, 286 }, 287 { } 288 }; 289 290 static int __init reboot_init(void) 291 { 292 dmi_check_system(reboot_dmi_table); 293 return 0; 294 } 295 core_initcall(reboot_init); 296 297 /* The following code and data reboots the machine by switching to real 298 mode and jumping to the BIOS reset entry point, as if the CPU has 299 really been reset. The previous version asked the keyboard 300 controller to pulse the CPU reset line, which is more thorough, but 301 doesn't work with at least one type of 486 motherboard. It is easy 302 to stop this code working; hence the copious comments. */ 303 static const unsigned long long 304 real_mode_gdt_entries [3] = 305 { 306 0x0000000000000000ULL, /* Null descriptor */ 307 0x00009b000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */ 308 0x000093000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */ 309 }; 310 311 static const struct desc_ptr 312 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries }, 313 real_mode_idt = { 0x3ff, 0 }; 314 315 /* This is 16-bit protected mode code to disable paging and the cache, 316 switch to real mode and jump to the BIOS reset code. 317 318 The instruction that switches to real mode by writing to CR0 must be 319 followed immediately by a far jump instruction, which set CS to a 320 valid value for real mode, and flushes the prefetch queue to avoid 321 running instructions that have already been decoded in protected 322 mode. 323 324 Clears all the flags except ET, especially PG (paging), PE 325 (protected-mode enable) and TS (task switch for coprocessor state 326 save). Flushes the TLB after paging has been disabled. Sets CD and 327 NW, to disable the cache on a 486, and invalidates the cache. This 328 is more like the state of a 486 after reset. I don't know if 329 something else should be done for other chips. 330 331 More could be done here to set up the registers as if a CPU reset had 332 occurred; hopefully real BIOSs don't assume much. */ 333 static const unsigned char real_mode_switch [] = 334 { 335 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */ 336 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */ 337 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */ 338 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */ 339 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */ 340 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */ 341 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */ 342 0x74, 0x02, /* jz f */ 343 0x0f, 0x09, /* wbinvd */ 344 0x24, 0x10, /* f: andb $0x10,al */ 345 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */ 346 }; 347 static const unsigned char jump_to_bios [] = 348 { 349 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */ 350 }; 351 352 /* 353 * Switch to real mode and then execute the code 354 * specified by the code and length parameters. 355 * We assume that length will aways be less that 100! 356 */ 357 void machine_real_restart(const unsigned char *code, int length) 358 { 359 local_irq_disable(); 360 361 /* Write zero to CMOS register number 0x0f, which the BIOS POST 362 routine will recognize as telling it to do a proper reboot. (Well 363 that's what this book in front of me says -- it may only apply to 364 the Phoenix BIOS though, it's not clear). At the same time, 365 disable NMIs by setting the top bit in the CMOS address register, 366 as we're about to do peculiar things to the CPU. I'm not sure if 367 `outb_p' is needed instead of just `outb'. Use it to be on the 368 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) 369 */ 370 spin_lock(&rtc_lock); 371 CMOS_WRITE(0x00, 0x8f); 372 spin_unlock(&rtc_lock); 373 374 /* Remap the kernel at virtual address zero, as well as offset zero 375 from the kernel segment. This assumes the kernel segment starts at 376 virtual address PAGE_OFFSET. */ 377 memcpy(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY, 378 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS); 379 380 /* 381 * Use `swapper_pg_dir' as our page directory. 382 */ 383 load_cr3(swapper_pg_dir); 384 385 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads 386 this on booting to tell it to "Bypass memory test (also warm 387 boot)". This seems like a fairly standard thing that gets set by 388 REBOOT.COM programs, and the previous reset routine did this 389 too. */ 390 *((unsigned short *)0x472) = reboot_mode; 391 392 /* For the switch to real mode, copy some code to low memory. It has 393 to be in the first 64k because it is running in 16-bit mode, and it 394 has to have the same physical and virtual address, because it turns 395 off paging. Copy it near the end of the first page, out of the way 396 of BIOS variables. */ 397 memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100), 398 real_mode_switch, sizeof (real_mode_switch)); 399 memcpy((void *)(0x1000 - 100), code, length); 400 401 /* Set up the IDT for real mode. */ 402 load_idt(&real_mode_idt); 403 404 /* Set up a GDT from which we can load segment descriptors for real 405 mode. The GDT is not used in real mode; it is just needed here to 406 prepare the descriptors. */ 407 load_gdt(&real_mode_gdt); 408 409 /* Load the data segment registers, and thus the descriptors ready for 410 real mode. The base address of each segment is 0x100, 16 times the 411 selector value being loaded here. This is so that the segment 412 registers don't have to be reloaded after switching to real mode: 413 the values are consistent for real mode operation already. */ 414 __asm__ __volatile__ ("movl $0x0010,%%eax\n" 415 "\tmovl %%eax,%%ds\n" 416 "\tmovl %%eax,%%es\n" 417 "\tmovl %%eax,%%fs\n" 418 "\tmovl %%eax,%%gs\n" 419 "\tmovl %%eax,%%ss" : : : "eax"); 420 421 /* Jump to the 16-bit code that we copied earlier. It disables paging 422 and the cache, switches to real mode, and jumps to the BIOS reset 423 entry point. */ 424 __asm__ __volatile__ ("ljmp $0x0008,%0" 425 : 426 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100))); 427 } 428 #ifdef CONFIG_APM_MODULE 429 EXPORT_SYMBOL(machine_real_restart); 430 #endif 431 432 #endif /* CONFIG_X86_32 */ 433 434 /* 435 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot 436 */ 437 static int __init set_pci_reboot(const struct dmi_system_id *d) 438 { 439 if (reboot_type != BOOT_CF9) { 440 reboot_type = BOOT_CF9; 441 printk(KERN_INFO "%s series board detected. " 442 "Selecting PCI-method for reboots.\n", d->ident); 443 } 444 return 0; 445 } 446 447 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = { 448 { /* Handle problems with rebooting on Apple MacBook5 */ 449 .callback = set_pci_reboot, 450 .ident = "Apple MacBook5", 451 .matches = { 452 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 453 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"), 454 }, 455 }, 456 { /* Handle problems with rebooting on Apple MacBookPro5 */ 457 .callback = set_pci_reboot, 458 .ident = "Apple MacBookPro5", 459 .matches = { 460 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 461 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"), 462 }, 463 }, 464 { /* Handle problems with rebooting on Apple Macmini3,1 */ 465 .callback = set_pci_reboot, 466 .ident = "Apple Macmini3,1", 467 .matches = { 468 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 469 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"), 470 }, 471 }, 472 { /* Handle problems with rebooting on the iMac9,1. */ 473 .callback = set_pci_reboot, 474 .ident = "Apple iMac9,1", 475 .matches = { 476 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 477 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"), 478 }, 479 }, 480 { } 481 }; 482 483 static int __init pci_reboot_init(void) 484 { 485 dmi_check_system(pci_reboot_dmi_table); 486 return 0; 487 } 488 core_initcall(pci_reboot_init); 489 490 static inline void kb_wait(void) 491 { 492 int i; 493 494 for (i = 0; i < 0x10000; i++) { 495 if ((inb(0x64) & 0x02) == 0) 496 break; 497 udelay(2); 498 } 499 } 500 501 static void vmxoff_nmi(int cpu, struct die_args *args) 502 { 503 cpu_emergency_vmxoff(); 504 } 505 506 /* Use NMIs as IPIs to tell all CPUs to disable virtualization 507 */ 508 static void emergency_vmx_disable_all(void) 509 { 510 /* Just make sure we won't change CPUs while doing this */ 511 local_irq_disable(); 512 513 /* We need to disable VMX on all CPUs before rebooting, otherwise 514 * we risk hanging up the machine, because the CPU ignore INIT 515 * signals when VMX is enabled. 516 * 517 * We can't take any locks and we may be on an inconsistent 518 * state, so we use NMIs as IPIs to tell the other CPUs to disable 519 * VMX and halt. 520 * 521 * For safety, we will avoid running the nmi_shootdown_cpus() 522 * stuff unnecessarily, but we don't have a way to check 523 * if other CPUs have VMX enabled. So we will call it only if the 524 * CPU we are running on has VMX enabled. 525 * 526 * We will miss cases where VMX is not enabled on all CPUs. This 527 * shouldn't do much harm because KVM always enable VMX on all 528 * CPUs anyway. But we can miss it on the small window where KVM 529 * is still enabling VMX. 530 */ 531 if (cpu_has_vmx() && cpu_vmx_enabled()) { 532 /* Disable VMX on this CPU. 533 */ 534 cpu_vmxoff(); 535 536 /* Halt and disable VMX on the other CPUs */ 537 nmi_shootdown_cpus(vmxoff_nmi); 538 539 } 540 } 541 542 543 void __attribute__((weak)) mach_reboot_fixups(void) 544 { 545 } 546 547 static void native_machine_emergency_restart(void) 548 { 549 int i; 550 551 if (reboot_emergency) 552 emergency_vmx_disable_all(); 553 554 tboot_shutdown(TB_SHUTDOWN_REBOOT); 555 556 /* Tell the BIOS if we want cold or warm reboot */ 557 *((unsigned short *)__va(0x472)) = reboot_mode; 558 559 for (;;) { 560 /* Could also try the reset bit in the Hammer NB */ 561 switch (reboot_type) { 562 case BOOT_KBD: 563 mach_reboot_fixups(); /* for board specific fixups */ 564 565 for (i = 0; i < 10; i++) { 566 kb_wait(); 567 udelay(50); 568 outb(0xfe, 0x64); /* pulse reset low */ 569 udelay(50); 570 } 571 572 case BOOT_TRIPLE: 573 load_idt(&no_idt); 574 __asm__ __volatile__("int3"); 575 576 reboot_type = BOOT_KBD; 577 break; 578 579 #ifdef CONFIG_X86_32 580 case BOOT_BIOS: 581 machine_real_restart(jump_to_bios, sizeof(jump_to_bios)); 582 583 reboot_type = BOOT_KBD; 584 break; 585 #endif 586 587 case BOOT_ACPI: 588 acpi_reboot(); 589 reboot_type = BOOT_KBD; 590 break; 591 592 case BOOT_EFI: 593 if (efi_enabled) 594 efi.reset_system(reboot_mode ? 595 EFI_RESET_WARM : 596 EFI_RESET_COLD, 597 EFI_SUCCESS, 0, NULL); 598 reboot_type = BOOT_KBD; 599 break; 600 601 case BOOT_CF9: 602 port_cf9_safe = true; 603 /* fall through */ 604 605 case BOOT_CF9_COND: 606 if (port_cf9_safe) { 607 u8 cf9 = inb(0xcf9) & ~6; 608 outb(cf9|2, 0xcf9); /* Request hard reset */ 609 udelay(50); 610 outb(cf9|6, 0xcf9); /* Actually do the reset */ 611 udelay(50); 612 } 613 reboot_type = BOOT_KBD; 614 break; 615 } 616 } 617 } 618 619 void native_machine_shutdown(void) 620 { 621 /* Stop the cpus and apics */ 622 #ifdef CONFIG_SMP 623 624 /* The boot cpu is always logical cpu 0 */ 625 int reboot_cpu_id = 0; 626 627 #ifdef CONFIG_X86_32 628 /* See if there has been given a command line override */ 629 if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) && 630 cpu_online(reboot_cpu)) 631 reboot_cpu_id = reboot_cpu; 632 #endif 633 634 /* Make certain the cpu I'm about to reboot on is online */ 635 if (!cpu_online(reboot_cpu_id)) 636 reboot_cpu_id = smp_processor_id(); 637 638 /* Make certain I only run on the appropriate processor */ 639 set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id)); 640 641 /* O.K Now that I'm on the appropriate processor, 642 * stop all of the others. 643 */ 644 smp_send_stop(); 645 #endif 646 647 lapic_shutdown(); 648 649 #ifdef CONFIG_X86_IO_APIC 650 disable_IO_APIC(); 651 #endif 652 653 #ifdef CONFIG_HPET_TIMER 654 hpet_disable(); 655 #endif 656 657 #ifdef CONFIG_X86_64 658 x86_platform.iommu_shutdown(); 659 #endif 660 } 661 662 static void __machine_emergency_restart(int emergency) 663 { 664 reboot_emergency = emergency; 665 machine_ops.emergency_restart(); 666 } 667 668 static void native_machine_restart(char *__unused) 669 { 670 printk("machine restart\n"); 671 672 if (!reboot_force) 673 machine_shutdown(); 674 __machine_emergency_restart(0); 675 } 676 677 static void native_machine_halt(void) 678 { 679 /* stop other cpus and apics */ 680 machine_shutdown(); 681 682 tboot_shutdown(TB_SHUTDOWN_HALT); 683 684 /* stop this cpu */ 685 stop_this_cpu(NULL); 686 } 687 688 static void native_machine_power_off(void) 689 { 690 if (pm_power_off) { 691 if (!reboot_force) 692 machine_shutdown(); 693 pm_power_off(); 694 } 695 /* a fallback in case there is no PM info available */ 696 tboot_shutdown(TB_SHUTDOWN_HALT); 697 } 698 699 struct machine_ops machine_ops = { 700 .power_off = native_machine_power_off, 701 .shutdown = native_machine_shutdown, 702 .emergency_restart = native_machine_emergency_restart, 703 .restart = native_machine_restart, 704 .halt = native_machine_halt, 705 #ifdef CONFIG_KEXEC 706 .crash_shutdown = native_machine_crash_shutdown, 707 #endif 708 }; 709 710 void machine_power_off(void) 711 { 712 machine_ops.power_off(); 713 } 714 715 void machine_shutdown(void) 716 { 717 machine_ops.shutdown(); 718 } 719 720 void machine_emergency_restart(void) 721 { 722 __machine_emergency_restart(1); 723 } 724 725 void machine_restart(char *cmd) 726 { 727 machine_ops.restart(cmd); 728 } 729 730 void machine_halt(void) 731 { 732 machine_ops.halt(); 733 } 734 735 #ifdef CONFIG_KEXEC 736 void machine_crash_shutdown(struct pt_regs *regs) 737 { 738 machine_ops.crash_shutdown(regs); 739 } 740 #endif 741 742 743 #if defined(CONFIG_SMP) 744 745 /* This keeps a track of which one is crashing cpu. */ 746 static int crashing_cpu; 747 static nmi_shootdown_cb shootdown_callback; 748 749 static atomic_t waiting_for_crash_ipi; 750 751 static int crash_nmi_callback(struct notifier_block *self, 752 unsigned long val, void *data) 753 { 754 int cpu; 755 756 if (val != DIE_NMI_IPI) 757 return NOTIFY_OK; 758 759 cpu = raw_smp_processor_id(); 760 761 /* Don't do anything if this handler is invoked on crashing cpu. 762 * Otherwise, system will completely hang. Crashing cpu can get 763 * an NMI if system was initially booted with nmi_watchdog parameter. 764 */ 765 if (cpu == crashing_cpu) 766 return NOTIFY_STOP; 767 local_irq_disable(); 768 769 shootdown_callback(cpu, (struct die_args *)data); 770 771 atomic_dec(&waiting_for_crash_ipi); 772 /* Assume hlt works */ 773 halt(); 774 for (;;) 775 cpu_relax(); 776 777 return 1; 778 } 779 780 static void smp_send_nmi_allbutself(void) 781 { 782 apic->send_IPI_allbutself(NMI_VECTOR); 783 } 784 785 static struct notifier_block crash_nmi_nb = { 786 .notifier_call = crash_nmi_callback, 787 }; 788 789 /* Halt all other CPUs, calling the specified function on each of them 790 * 791 * This function can be used to halt all other CPUs on crash 792 * or emergency reboot time. The function passed as parameter 793 * will be called inside a NMI handler on all CPUs. 794 */ 795 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 796 { 797 unsigned long msecs; 798 local_irq_disable(); 799 800 /* Make a note of crashing cpu. Will be used in NMI callback.*/ 801 crashing_cpu = safe_smp_processor_id(); 802 803 shootdown_callback = callback; 804 805 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); 806 /* Would it be better to replace the trap vector here? */ 807 if (register_die_notifier(&crash_nmi_nb)) 808 return; /* return what? */ 809 /* Ensure the new callback function is set before sending 810 * out the NMI 811 */ 812 wmb(); 813 814 smp_send_nmi_allbutself(); 815 816 msecs = 1000; /* Wait at most a second for the other cpus to stop */ 817 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { 818 mdelay(1); 819 msecs--; 820 } 821 822 /* Leave the nmi callback set */ 823 } 824 #else /* !CONFIG_SMP */ 825 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 826 { 827 /* No other CPUs to shoot down */ 828 } 829 #endif 830