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/desc.h>
16 #include <asm/hpet.h>
17 #include <asm/pgtable.h>
18 #include <asm/proto.h>
19 #include <asm/reboot_fixups.h>
20 #include <asm/reboot.h>
21 #include <asm/pci_x86.h>
22 #include <asm/virtext.h>
23 #include <asm/cpu.h>
24 #include <asm/nmi.h>
25 #include <asm/smp.h>
26
27 #include <linux/ctype.h>
28 #include <linux/mc146818rtc.h>
29 #include <asm/realmode.h>
30 #include <asm/x86_init.h>
31
32 /*
33 * Power off function, if any
34 */
35 void (*pm_power_off)(void);
36 EXPORT_SYMBOL(pm_power_off);
37
38 static const struct desc_ptr no_idt = {};
39 static int reboot_mode;
40 enum reboot_type reboot_type = BOOT_ACPI;
41 int reboot_force;
42
43 /*
44 * This variable is used privately to keep track of whether or not
45 * reboot_type is still set to its default value (i.e., reboot= hasn't
46 * been set on the command line). This is needed so that we can
47 * suppress DMI scanning for reboot quirks. Without it, it's
48 * impossible to override a faulty reboot quirk without recompiling.
49 */
50 static int reboot_default = 1;
51
52 #ifdef CONFIG_SMP
53 static int reboot_cpu = -1;
54 #endif
55
56 /*
57 * This is set if we need to go through the 'emergency' path.
58 * When machine_emergency_restart() is called, we may be on
59 * an inconsistent state and won't be able to do a clean cleanup
60 */
61 static int reboot_emergency;
62
63 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
64 bool port_cf9_safe = false;
65
66 /*
67 * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
68 * warm Don't set the cold reboot flag
69 * cold Set the cold reboot flag
70 * bios Reboot by jumping through the BIOS
71 * smp Reboot by executing reset on BSP or other CPU
72 * triple Force a triple fault (init)
73 * kbd Use the keyboard controller. cold reset (default)
74 * acpi Use the RESET_REG in the FADT
75 * efi Use efi reset_system runtime service
76 * pci Use the so-called "PCI reset register", CF9
77 * force Avoid anything that could hang.
78 */
reboot_setup(char * str)79 static int __init reboot_setup(char *str)
80 {
81 for (;;) {
82 /*
83 * Having anything passed on the command line via
84 * reboot= will cause us to disable DMI checking
85 * below.
86 */
87 reboot_default = 0;
88
89 switch (*str) {
90 case 'w':
91 reboot_mode = 0x1234;
92 break;
93
94 case 'c':
95 reboot_mode = 0;
96 break;
97
98 #ifdef CONFIG_SMP
99 case 's':
100 if (isdigit(*(str+1))) {
101 reboot_cpu = (int) (*(str+1) - '0');
102 if (isdigit(*(str+2)))
103 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
104 }
105 /*
106 * We will leave sorting out the final value
107 * when we are ready to reboot, since we might not
108 * have detected BSP APIC ID or smp_num_cpu
109 */
110 break;
111 #endif /* CONFIG_SMP */
112
113 case 'b':
114 case 'a':
115 case 'k':
116 case 't':
117 case 'e':
118 case 'p':
119 reboot_type = *str;
120 break;
121
122 case 'f':
123 reboot_force = 1;
124 break;
125 }
126
127 str = strchr(str, ',');
128 if (str)
129 str++;
130 else
131 break;
132 }
133 return 1;
134 }
135
136 __setup("reboot=", reboot_setup);
137
138
139 /*
140 * Reboot options and system auto-detection code provided by
141 * Dell Inc. so their systems "just work". :-)
142 */
143
144 /*
145 * Some machines require the "reboot=b" or "reboot=k" commandline options,
146 * this quirk makes that automatic.
147 */
set_bios_reboot(const struct dmi_system_id * d)148 static int __init set_bios_reboot(const struct dmi_system_id *d)
149 {
150 if (reboot_type != BOOT_BIOS) {
151 reboot_type = BOOT_BIOS;
152 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
153 "BIOS", d->ident);
154 }
155 return 0;
156 }
157
machine_real_restart(unsigned int type)158 void __noreturn machine_real_restart(unsigned int type)
159 {
160 local_irq_disable();
161
162 /*
163 * Write zero to CMOS register number 0x0f, which the BIOS POST
164 * routine will recognize as telling it to do a proper reboot. (Well
165 * that's what this book in front of me says -- it may only apply to
166 * the Phoenix BIOS though, it's not clear). At the same time,
167 * disable NMIs by setting the top bit in the CMOS address register,
168 * as we're about to do peculiar things to the CPU. I'm not sure if
169 * `outb_p' is needed instead of just `outb'. Use it to be on the
170 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
171 */
172 spin_lock(&rtc_lock);
173 CMOS_WRITE(0x00, 0x8f);
174 spin_unlock(&rtc_lock);
175
176 /*
177 * Switch back to the initial page table.
178 */
179 #ifdef CONFIG_X86_32
180 load_cr3(initial_page_table);
181 #else
182 write_cr3(real_mode_header->trampoline_pgd);
183 #endif
184
185 /* Jump to the identity-mapped low memory code */
186 #ifdef CONFIG_X86_32
187 asm volatile("jmpl *%0" : :
188 "rm" (real_mode_header->machine_real_restart_asm),
189 "a" (type));
190 #else
191 asm volatile("ljmpl *%0" : :
192 "m" (real_mode_header->machine_real_restart_asm),
193 "D" (type));
194 #endif
195 unreachable();
196 }
197 #ifdef CONFIG_APM_MODULE
198 EXPORT_SYMBOL(machine_real_restart);
199 #endif
200
201 /*
202 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
203 */
set_pci_reboot(const struct dmi_system_id * d)204 static int __init set_pci_reboot(const struct dmi_system_id *d)
205 {
206 if (reboot_type != BOOT_CF9) {
207 reboot_type = BOOT_CF9;
208 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
209 "PCI", d->ident);
210 }
211 return 0;
212 }
213
set_kbd_reboot(const struct dmi_system_id * d)214 static int __init set_kbd_reboot(const struct dmi_system_id *d)
215 {
216 if (reboot_type != BOOT_KBD) {
217 reboot_type = BOOT_KBD;
218 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
219 "KBD", d->ident);
220 }
221 return 0;
222 }
223
224 /*
225 * This is a single dmi_table handling all reboot quirks.
226 */
227 static struct dmi_system_id __initdata reboot_dmi_table[] = {
228 { /* Handle problems with rebooting on Dell E520's */
229 .callback = set_bios_reboot,
230 .ident = "Dell E520",
231 .matches = {
232 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
233 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
234 },
235 },
236 { /* Handle problems with rebooting on Dell 1300's */
237 .callback = set_bios_reboot,
238 .ident = "Dell PowerEdge 1300",
239 .matches = {
240 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
241 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
242 },
243 },
244 { /* Handle problems with rebooting on Dell 300's */
245 .callback = set_bios_reboot,
246 .ident = "Dell PowerEdge 300",
247 .matches = {
248 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
249 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
250 },
251 },
252 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
253 .callback = set_bios_reboot,
254 .ident = "Dell OptiPlex 745",
255 .matches = {
256 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
257 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
258 },
259 },
260 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
261 .callback = set_bios_reboot,
262 .ident = "Dell OptiPlex 745",
263 .matches = {
264 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
265 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
266 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
267 },
268 },
269 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
270 .callback = set_bios_reboot,
271 .ident = "Dell OptiPlex 745",
272 .matches = {
273 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
274 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
275 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
276 },
277 },
278 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
279 .callback = set_bios_reboot,
280 .ident = "Dell OptiPlex 330",
281 .matches = {
282 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
283 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
284 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
285 },
286 },
287 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
288 .callback = set_bios_reboot,
289 .ident = "Dell OptiPlex 360",
290 .matches = {
291 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
292 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
293 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
294 },
295 },
296 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
297 .callback = set_bios_reboot,
298 .ident = "Dell OptiPlex 760",
299 .matches = {
300 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
301 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
302 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
303 },
304 },
305 { /* Handle problems with rebooting on Dell 2400's */
306 .callback = set_bios_reboot,
307 .ident = "Dell PowerEdge 2400",
308 .matches = {
309 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
310 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
311 },
312 },
313 { /* Handle problems with rebooting on Dell T5400's */
314 .callback = set_bios_reboot,
315 .ident = "Dell Precision T5400",
316 .matches = {
317 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
318 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
319 },
320 },
321 { /* Handle problems with rebooting on Dell T7400's */
322 .callback = set_bios_reboot,
323 .ident = "Dell Precision T7400",
324 .matches = {
325 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
326 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
327 },
328 },
329 { /* Handle problems with rebooting on HP laptops */
330 .callback = set_bios_reboot,
331 .ident = "HP Compaq Laptop",
332 .matches = {
333 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
334 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
335 },
336 },
337 { /* Handle problems with rebooting on Dell XPS710 */
338 .callback = set_bios_reboot,
339 .ident = "Dell XPS710",
340 .matches = {
341 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
342 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
343 },
344 },
345 { /* Handle problems with rebooting on Dell DXP061 */
346 .callback = set_bios_reboot,
347 .ident = "Dell DXP061",
348 .matches = {
349 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
350 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
351 },
352 },
353 { /* Handle problems with rebooting on Sony VGN-Z540N */
354 .callback = set_bios_reboot,
355 .ident = "Sony VGN-Z540N",
356 .matches = {
357 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
358 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
359 },
360 },
361 { /* Handle problems with rebooting on ASUS P4S800 */
362 .callback = set_bios_reboot,
363 .ident = "ASUS P4S800",
364 .matches = {
365 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
366 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
367 },
368 },
369
370 { /* Handle reboot issue on Acer Aspire one */
371 .callback = set_kbd_reboot,
372 .ident = "Acer Aspire One A110",
373 .matches = {
374 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
375 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
376 },
377 },
378 { /* Handle problems with rebooting on Apple MacBook5 */
379 .callback = set_pci_reboot,
380 .ident = "Apple MacBook5",
381 .matches = {
382 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
383 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
384 },
385 },
386 { /* Handle problems with rebooting on Apple MacBookPro5 */
387 .callback = set_pci_reboot,
388 .ident = "Apple MacBookPro5",
389 .matches = {
390 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
391 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
392 },
393 },
394 { /* Handle problems with rebooting on Apple Macmini3,1 */
395 .callback = set_pci_reboot,
396 .ident = "Apple Macmini3,1",
397 .matches = {
398 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
399 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
400 },
401 },
402 { /* Handle problems with rebooting on the iMac9,1. */
403 .callback = set_pci_reboot,
404 .ident = "Apple iMac9,1",
405 .matches = {
406 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
407 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
408 },
409 },
410 { /* Handle problems with rebooting on the Latitude E6320. */
411 .callback = set_pci_reboot,
412 .ident = "Dell Latitude E6320",
413 .matches = {
414 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
415 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
416 },
417 },
418 { /* Handle problems with rebooting on the Latitude E5420. */
419 .callback = set_pci_reboot,
420 .ident = "Dell Latitude E5420",
421 .matches = {
422 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
423 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
424 },
425 },
426 { /* Handle problems with rebooting on the Latitude E6420. */
427 .callback = set_pci_reboot,
428 .ident = "Dell Latitude E6420",
429 .matches = {
430 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
431 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
432 },
433 },
434 { /* Handle problems with rebooting on the OptiPlex 990. */
435 .callback = set_pci_reboot,
436 .ident = "Dell OptiPlex 990",
437 .matches = {
438 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
439 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
440 },
441 },
442 { /* Handle problems with rebooting on the Precision M6600. */
443 .callback = set_pci_reboot,
444 .ident = "Dell OptiPlex 990",
445 .matches = {
446 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
447 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
448 },
449 },
450 { }
451 };
452
reboot_init(void)453 static int __init reboot_init(void)
454 {
455 /*
456 * Only do the DMI check if reboot_type hasn't been overridden
457 * on the command line
458 */
459 if (reboot_default)
460 dmi_check_system(reboot_dmi_table);
461 return 0;
462 }
463 core_initcall(reboot_init);
464
kb_wait(void)465 static inline void kb_wait(void)
466 {
467 int i;
468
469 for (i = 0; i < 0x10000; i++) {
470 if ((inb(0x64) & 0x02) == 0)
471 break;
472 udelay(2);
473 }
474 }
475
vmxoff_nmi(int cpu,struct pt_regs * regs)476 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
477 {
478 cpu_emergency_vmxoff();
479 }
480
481 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
emergency_vmx_disable_all(void)482 static void emergency_vmx_disable_all(void)
483 {
484 /* Just make sure we won't change CPUs while doing this */
485 local_irq_disable();
486
487 /*
488 * We need to disable VMX on all CPUs before rebooting, otherwise
489 * we risk hanging up the machine, because the CPU ignore INIT
490 * signals when VMX is enabled.
491 *
492 * We can't take any locks and we may be on an inconsistent
493 * state, so we use NMIs as IPIs to tell the other CPUs to disable
494 * VMX and halt.
495 *
496 * For safety, we will avoid running the nmi_shootdown_cpus()
497 * stuff unnecessarily, but we don't have a way to check
498 * if other CPUs have VMX enabled. So we will call it only if the
499 * CPU we are running on has VMX enabled.
500 *
501 * We will miss cases where VMX is not enabled on all CPUs. This
502 * shouldn't do much harm because KVM always enable VMX on all
503 * CPUs anyway. But we can miss it on the small window where KVM
504 * is still enabling VMX.
505 */
506 if (cpu_has_vmx() && cpu_vmx_enabled()) {
507 /* Disable VMX on this CPU. */
508 cpu_vmxoff();
509
510 /* Halt and disable VMX on the other CPUs */
511 nmi_shootdown_cpus(vmxoff_nmi);
512
513 }
514 }
515
516
mach_reboot_fixups(void)517 void __attribute__((weak)) mach_reboot_fixups(void)
518 {
519 }
520
521 /*
522 * Windows compatible x86 hardware expects the following on reboot:
523 *
524 * 1) If the FADT has the ACPI reboot register flag set, try it
525 * 2) If still alive, write to the keyboard controller
526 * 3) If still alive, write to the ACPI reboot register again
527 * 4) If still alive, write to the keyboard controller again
528 *
529 * If the machine is still alive at this stage, it gives up. We default to
530 * following the same pattern, except that if we're still alive after (4) we'll
531 * try to force a triple fault and then cycle between hitting the keyboard
532 * controller and doing that
533 */
native_machine_emergency_restart(void)534 static void native_machine_emergency_restart(void)
535 {
536 int i;
537 int attempt = 0;
538 int orig_reboot_type = reboot_type;
539
540 if (reboot_emergency)
541 emergency_vmx_disable_all();
542
543 tboot_shutdown(TB_SHUTDOWN_REBOOT);
544
545 /* Tell the BIOS if we want cold or warm reboot */
546 *((unsigned short *)__va(0x472)) = reboot_mode;
547
548 for (;;) {
549 /* Could also try the reset bit in the Hammer NB */
550 switch (reboot_type) {
551 case BOOT_KBD:
552 mach_reboot_fixups(); /* For board specific fixups */
553
554 for (i = 0; i < 10; i++) {
555 kb_wait();
556 udelay(50);
557 outb(0xfe, 0x64); /* Pulse reset low */
558 udelay(50);
559 }
560 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
561 attempt = 1;
562 reboot_type = BOOT_ACPI;
563 } else {
564 reboot_type = BOOT_TRIPLE;
565 }
566 break;
567
568 case BOOT_TRIPLE:
569 load_idt(&no_idt);
570 __asm__ __volatile__("int3");
571
572 reboot_type = BOOT_KBD;
573 break;
574
575 case BOOT_BIOS:
576 machine_real_restart(MRR_BIOS);
577
578 reboot_type = BOOT_KBD;
579 break;
580
581 case BOOT_ACPI:
582 acpi_reboot();
583 reboot_type = BOOT_KBD;
584 break;
585
586 case BOOT_EFI:
587 if (efi_enabled(EFI_RUNTIME_SERVICES))
588 efi.reset_system(reboot_mode ?
589 EFI_RESET_WARM :
590 EFI_RESET_COLD,
591 EFI_SUCCESS, 0, NULL);
592 reboot_type = BOOT_KBD;
593 break;
594
595 case BOOT_CF9:
596 port_cf9_safe = true;
597 /* Fall through */
598
599 case BOOT_CF9_COND:
600 if (port_cf9_safe) {
601 u8 cf9 = inb(0xcf9) & ~6;
602 outb(cf9|2, 0xcf9); /* Request hard reset */
603 udelay(50);
604 outb(cf9|6, 0xcf9); /* Actually do the reset */
605 udelay(50);
606 }
607 reboot_type = BOOT_KBD;
608 break;
609 }
610 }
611 }
612
native_machine_shutdown(void)613 void native_machine_shutdown(void)
614 {
615 /* Stop the cpus and apics */
616 #ifdef CONFIG_SMP
617
618 /* The boot cpu is always logical cpu 0 */
619 int reboot_cpu_id = 0;
620
621 /* See if there has been given a command line override */
622 if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
623 cpu_online(reboot_cpu))
624 reboot_cpu_id = reboot_cpu;
625
626 /* Make certain the cpu I'm about to reboot on is online */
627 if (!cpu_online(reboot_cpu_id))
628 reboot_cpu_id = smp_processor_id();
629
630 /* Make certain I only run on the appropriate processor */
631 set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
632
633 /*
634 * O.K Now that I'm on the appropriate processor, stop all of the
635 * others. Also disable the local irq to not receive the per-cpu
636 * timer interrupt which may trigger scheduler's load balance.
637 */
638 local_irq_disable();
639 stop_other_cpus();
640 #endif
641
642 lapic_shutdown();
643
644 #ifdef CONFIG_X86_IO_APIC
645 disable_IO_APIC();
646 #endif
647
648 #ifdef CONFIG_HPET_TIMER
649 hpet_disable();
650 #endif
651
652 #ifdef CONFIG_X86_64
653 x86_platform.iommu_shutdown();
654 #endif
655 }
656
__machine_emergency_restart(int emergency)657 static void __machine_emergency_restart(int emergency)
658 {
659 reboot_emergency = emergency;
660 machine_ops.emergency_restart();
661 }
662
native_machine_restart(char * __unused)663 static void native_machine_restart(char *__unused)
664 {
665 pr_notice("machine restart\n");
666
667 if (!reboot_force)
668 machine_shutdown();
669 __machine_emergency_restart(0);
670 }
671
native_machine_halt(void)672 static void native_machine_halt(void)
673 {
674 /* Stop other cpus and apics */
675 machine_shutdown();
676
677 tboot_shutdown(TB_SHUTDOWN_HALT);
678
679 stop_this_cpu(NULL);
680 }
681
native_machine_power_off(void)682 static void native_machine_power_off(void)
683 {
684 if (pm_power_off) {
685 if (!reboot_force)
686 machine_shutdown();
687 pm_power_off();
688 }
689 /* A fallback in case there is no PM info available */
690 tboot_shutdown(TB_SHUTDOWN_HALT);
691 }
692
693 struct machine_ops machine_ops = {
694 .power_off = native_machine_power_off,
695 .shutdown = native_machine_shutdown,
696 .emergency_restart = native_machine_emergency_restart,
697 .restart = native_machine_restart,
698 .halt = native_machine_halt,
699 #ifdef CONFIG_KEXEC
700 .crash_shutdown = native_machine_crash_shutdown,
701 #endif
702 };
703
machine_power_off(void)704 void machine_power_off(void)
705 {
706 machine_ops.power_off();
707 }
708
machine_shutdown(void)709 void machine_shutdown(void)
710 {
711 machine_ops.shutdown();
712 }
713
machine_emergency_restart(void)714 void machine_emergency_restart(void)
715 {
716 __machine_emergency_restart(1);
717 }
718
machine_restart(char * cmd)719 void machine_restart(char *cmd)
720 {
721 machine_ops.restart(cmd);
722 }
723
machine_halt(void)724 void machine_halt(void)
725 {
726 machine_ops.halt();
727 }
728
729 #ifdef CONFIG_KEXEC
machine_crash_shutdown(struct pt_regs * regs)730 void machine_crash_shutdown(struct pt_regs *regs)
731 {
732 machine_ops.crash_shutdown(regs);
733 }
734 #endif
735
736
737 #if defined(CONFIG_SMP)
738
739 /* This keeps a track of which one is crashing cpu. */
740 static int crashing_cpu;
741 static nmi_shootdown_cb shootdown_callback;
742
743 static atomic_t waiting_for_crash_ipi;
744
crash_nmi_callback(unsigned int val,struct pt_regs * regs)745 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
746 {
747 int cpu;
748
749 cpu = raw_smp_processor_id();
750
751 /*
752 * Don't do anything if this handler is invoked on crashing cpu.
753 * Otherwise, system will completely hang. Crashing cpu can get
754 * an NMI if system was initially booted with nmi_watchdog parameter.
755 */
756 if (cpu == crashing_cpu)
757 return NMI_HANDLED;
758 local_irq_disable();
759
760 shootdown_callback(cpu, regs);
761
762 atomic_dec(&waiting_for_crash_ipi);
763 /* Assume hlt works */
764 halt();
765 for (;;)
766 cpu_relax();
767
768 return NMI_HANDLED;
769 }
770
smp_send_nmi_allbutself(void)771 static void smp_send_nmi_allbutself(void)
772 {
773 apic->send_IPI_allbutself(NMI_VECTOR);
774 }
775
776 /*
777 * Halt all other CPUs, calling the specified function on each of them
778 *
779 * This function can be used to halt all other CPUs on crash
780 * or emergency reboot time. The function passed as parameter
781 * will be called inside a NMI handler on all CPUs.
782 */
nmi_shootdown_cpus(nmi_shootdown_cb callback)783 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
784 {
785 unsigned long msecs;
786 local_irq_disable();
787
788 /* Make a note of crashing cpu. Will be used in NMI callback. */
789 crashing_cpu = safe_smp_processor_id();
790
791 shootdown_callback = callback;
792
793 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
794 /* Would it be better to replace the trap vector here? */
795 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
796 NMI_FLAG_FIRST, "crash"))
797 return; /* Return what? */
798 /*
799 * Ensure the new callback function is set before sending
800 * out the NMI
801 */
802 wmb();
803
804 smp_send_nmi_allbutself();
805
806 msecs = 1000; /* Wait at most a second for the other cpus to stop */
807 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
808 mdelay(1);
809 msecs--;
810 }
811
812 /* Leave the nmi callback set */
813 }
814 #else /* !CONFIG_SMP */
nmi_shootdown_cpus(nmi_shootdown_cb callback)815 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
816 {
817 /* No other CPUs to shoot down */
818 }
819 #endif
820