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1// SPDX-License-Identifier: GPL-2.0
2#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
3
4#include <linux/export.h>
5#include <linux/reboot.h>
6#include <linux/init.h>
7#include <linux/pm.h>
8#include <linux/efi.h>
9#include <linux/dmi.h>
10#include <linux/sched.h>
11#include <linux/tboot.h>
12#include <linux/delay.h>
13#include <linux/frame.h>
14#include <acpi/reboot.h>
15#include <asm/io.h>
16#include <asm/apic.h>
17#include <asm/io_apic.h>
18#include <asm/desc.h>
19#include <asm/hpet.h>
20#include <asm/pgtable.h>
21#include <asm/proto.h>
22#include <asm/reboot_fixups.h>
23#include <asm/reboot.h>
24#include <asm/pci_x86.h>
25#include <asm/virtext.h>
26#include <asm/cpu.h>
27#include <asm/nmi.h>
28#include <asm/smp.h>
29
30#include <linux/ctype.h>
31#include <linux/mc146818rtc.h>
32#include <asm/realmode.h>
33#include <asm/x86_init.h>
34#include <asm/efi.h>
35
36/*
37 * Power off function, if any
38 */
39void (*pm_power_off)(void);
40EXPORT_SYMBOL(pm_power_off);
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 */
47static int reboot_emergency;
48
49/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
50bool 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=a" commandline options
59 */
60static int __init set_acpi_reboot(const struct dmi_system_id *d)
61{
62 if (reboot_type != BOOT_ACPI) {
63 reboot_type = BOOT_ACPI;
64 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
65 d->ident, "ACPI");
66 }
67 return 0;
68}
69
70/*
71 * Some machines require the "reboot=b" or "reboot=k" commandline options,
72 * this quirk makes that automatic.
73 */
74static int __init set_bios_reboot(const struct dmi_system_id *d)
75{
76 if (reboot_type != BOOT_BIOS) {
77 reboot_type = BOOT_BIOS;
78 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
79 d->ident, "BIOS");
80 }
81 return 0;
82}
83
84void __noreturn machine_real_restart(unsigned int type)
85{
86 local_irq_disable();
87
88 /*
89 * Write zero to CMOS register number 0x0f, which the BIOS POST
90 * routine will recognize as telling it to do a proper reboot. (Well
91 * that's what this book in front of me says -- it may only apply to
92 * the Phoenix BIOS though, it's not clear). At the same time,
93 * disable NMIs by setting the top bit in the CMOS address register,
94 * as we're about to do peculiar things to the CPU. I'm not sure if
95 * `outb_p' is needed instead of just `outb'. Use it to be on the
96 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
97 */
98 spin_lock(&rtc_lock);
99 CMOS_WRITE(0x00, 0x8f);
100 spin_unlock(&rtc_lock);
101
102 /*
103 * Switch back to the initial page table.
104 */
105#ifdef CONFIG_X86_32
106 load_cr3(initial_page_table);
107#else
108 write_cr3(real_mode_header->trampoline_pgd);
109
110 /* Exiting long mode will fail if CR4.PCIDE is set. */
111 if (static_cpu_has(X86_FEATURE_PCID))
112 cr4_clear_bits(X86_CR4_PCIDE);
113#endif
114
115 /* Jump to the identity-mapped low memory code */
116#ifdef CONFIG_X86_32
117 asm volatile("jmpl *%0" : :
118 "rm" (real_mode_header->machine_real_restart_asm),
119 "a" (type));
120#else
121 asm volatile("ljmpl *%0" : :
122 "m" (real_mode_header->machine_real_restart_asm),
123 "D" (type));
124#endif
125 unreachable();
126}
127#ifdef CONFIG_APM_MODULE
128EXPORT_SYMBOL(machine_real_restart);
129#endif
130STACK_FRAME_NON_STANDARD(machine_real_restart);
131
132/*
133 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
134 */
135static int __init set_pci_reboot(const struct dmi_system_id *d)
136{
137 if (reboot_type != BOOT_CF9_FORCE) {
138 reboot_type = BOOT_CF9_FORCE;
139 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
140 d->ident, "PCI");
141 }
142 return 0;
143}
144
145static int __init set_kbd_reboot(const struct dmi_system_id *d)
146{
147 if (reboot_type != BOOT_KBD) {
148 reboot_type = BOOT_KBD;
149 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
150 d->ident, "KBD");
151 }
152 return 0;
153}
154
155/*
156 * This is a single dmi_table handling all reboot quirks.
157 */
158static const struct dmi_system_id reboot_dmi_table[] __initconst = {
159
160 /* Acer */
161 { /* Handle reboot issue on Acer Aspire one */
162 .callback = set_kbd_reboot,
163 .ident = "Acer Aspire One A110",
164 .matches = {
165 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
166 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
167 },
168 },
169
170 /* Apple */
171 { /* Handle problems with rebooting on Apple MacBook5 */
172 .callback = set_pci_reboot,
173 .ident = "Apple MacBook5",
174 .matches = {
175 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
176 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
177 },
178 },
179 { /* Handle problems with rebooting on Apple MacBookPro5 */
180 .callback = set_pci_reboot,
181 .ident = "Apple MacBookPro5",
182 .matches = {
183 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
184 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
185 },
186 },
187 { /* Handle problems with rebooting on Apple Macmini3,1 */
188 .callback = set_pci_reboot,
189 .ident = "Apple Macmini3,1",
190 .matches = {
191 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
192 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
193 },
194 },
195 { /* Handle problems with rebooting on the iMac9,1. */
196 .callback = set_pci_reboot,
197 .ident = "Apple iMac9,1",
198 .matches = {
199 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
200 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
201 },
202 },
203 { /* Handle problems with rebooting on the iMac10,1. */
204 .callback = set_pci_reboot,
205 .ident = "Apple iMac10,1",
206 .matches = {
207 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
208 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
209 },
210 },
211
212 /* ASRock */
213 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
214 .callback = set_pci_reboot,
215 .ident = "ASRock Q1900DC-ITX",
216 .matches = {
217 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
218 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
219 },
220 },
221
222 /* ASUS */
223 { /* Handle problems with rebooting on ASUS P4S800 */
224 .callback = set_bios_reboot,
225 .ident = "ASUS P4S800",
226 .matches = {
227 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
228 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
229 },
230 },
231 { /* Handle problems with rebooting on ASUS EeeBook X205TA */
232 .callback = set_acpi_reboot,
233 .ident = "ASUS EeeBook X205TA",
234 .matches = {
235 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
236 DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"),
237 },
238 },
239 { /* Handle problems with rebooting on ASUS EeeBook X205TAW */
240 .callback = set_acpi_reboot,
241 .ident = "ASUS EeeBook X205TAW",
242 .matches = {
243 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
244 DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"),
245 },
246 },
247
248 /* Certec */
249 { /* Handle problems with rebooting on Certec BPC600 */
250 .callback = set_pci_reboot,
251 .ident = "Certec BPC600",
252 .matches = {
253 DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
254 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
255 },
256 },
257
258 /* Dell */
259 { /* Handle problems with rebooting on Dell DXP061 */
260 .callback = set_bios_reboot,
261 .ident = "Dell DXP061",
262 .matches = {
263 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
264 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
265 },
266 },
267 { /* Handle problems with rebooting on Dell E520's */
268 .callback = set_bios_reboot,
269 .ident = "Dell E520",
270 .matches = {
271 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
272 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
273 },
274 },
275 { /* Handle problems with rebooting on the Latitude E5410. */
276 .callback = set_pci_reboot,
277 .ident = "Dell Latitude E5410",
278 .matches = {
279 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
280 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
281 },
282 },
283 { /* Handle problems with rebooting on the Latitude E5420. */
284 .callback = set_pci_reboot,
285 .ident = "Dell Latitude E5420",
286 .matches = {
287 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
288 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
289 },
290 },
291 { /* Handle problems with rebooting on the Latitude E6320. */
292 .callback = set_pci_reboot,
293 .ident = "Dell Latitude E6320",
294 .matches = {
295 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
296 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
297 },
298 },
299 { /* Handle problems with rebooting on the Latitude E6420. */
300 .callback = set_pci_reboot,
301 .ident = "Dell Latitude E6420",
302 .matches = {
303 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
304 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
305 },
306 },
307 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
308 .callback = set_bios_reboot,
309 .ident = "Dell OptiPlex 330",
310 .matches = {
311 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
312 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
313 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
314 },
315 },
316 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
317 .callback = set_bios_reboot,
318 .ident = "Dell OptiPlex 360",
319 .matches = {
320 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
321 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
322 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
323 },
324 },
325 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
326 .callback = set_bios_reboot,
327 .ident = "Dell OptiPlex 745",
328 .matches = {
329 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
330 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
331 },
332 },
333 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
334 .callback = set_bios_reboot,
335 .ident = "Dell OptiPlex 745",
336 .matches = {
337 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
338 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
339 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
340 },
341 },
342 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
343 .callback = set_bios_reboot,
344 .ident = "Dell OptiPlex 745",
345 .matches = {
346 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
347 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
348 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
349 },
350 },
351 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
352 .callback = set_bios_reboot,
353 .ident = "Dell OptiPlex 760",
354 .matches = {
355 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
356 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
357 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
358 },
359 },
360 { /* Handle problems with rebooting on the OptiPlex 990. */
361 .callback = set_pci_reboot,
362 .ident = "Dell OptiPlex 990",
363 .matches = {
364 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
365 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
366 },
367 },
368 { /* Handle problems with rebooting on Dell 300's */
369 .callback = set_bios_reboot,
370 .ident = "Dell PowerEdge 300",
371 .matches = {
372 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
373 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
374 },
375 },
376 { /* Handle problems with rebooting on Dell 1300's */
377 .callback = set_bios_reboot,
378 .ident = "Dell PowerEdge 1300",
379 .matches = {
380 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
381 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
382 },
383 },
384 { /* Handle problems with rebooting on Dell 2400's */
385 .callback = set_bios_reboot,
386 .ident = "Dell PowerEdge 2400",
387 .matches = {
388 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
389 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
390 },
391 },
392 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
393 .callback = set_pci_reboot,
394 .ident = "Dell PowerEdge C6100",
395 .matches = {
396 DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
397 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
398 },
399 },
400 { /* Handle problems with rebooting on the Precision M6600. */
401 .callback = set_pci_reboot,
402 .ident = "Dell Precision M6600",
403 .matches = {
404 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
405 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
406 },
407 },
408 { /* Handle problems with rebooting on Dell T5400's */
409 .callback = set_bios_reboot,
410 .ident = "Dell Precision T5400",
411 .matches = {
412 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
413 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
414 },
415 },
416 { /* Handle problems with rebooting on Dell T7400's */
417 .callback = set_bios_reboot,
418 .ident = "Dell Precision T7400",
419 .matches = {
420 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
421 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
422 },
423 },
424 { /* Handle problems with rebooting on Dell XPS710 */
425 .callback = set_bios_reboot,
426 .ident = "Dell XPS710",
427 .matches = {
428 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
429 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
430 },
431 },
432 { /* Handle problems with rebooting on Dell Optiplex 7450 AIO */
433 .callback = set_acpi_reboot,
434 .ident = "Dell OptiPlex 7450 AIO",
435 .matches = {
436 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
437 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"),
438 },
439 },
440
441 /* Hewlett-Packard */
442 { /* Handle problems with rebooting on HP laptops */
443 .callback = set_bios_reboot,
444 .ident = "HP Compaq Laptop",
445 .matches = {
446 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
447 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
448 },
449 },
450
451 /* Sony */
452 { /* Handle problems with rebooting on Sony VGN-Z540N */
453 .callback = set_bios_reboot,
454 .ident = "Sony VGN-Z540N",
455 .matches = {
456 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
457 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
458 },
459 },
460
461 { }
462};
463
464static int __init reboot_init(void)
465{
466 int rv;
467
468 /*
469 * Only do the DMI check if reboot_type hasn't been overridden
470 * on the command line
471 */
472 if (!reboot_default)
473 return 0;
474
475 /*
476 * The DMI quirks table takes precedence. If no quirks entry
477 * matches and the ACPI Hardware Reduced bit is set and EFI
478 * runtime services are enabled, force EFI reboot.
479 */
480 rv = dmi_check_system(reboot_dmi_table);
481
482 if (!rv && efi_reboot_required() && !efi_runtime_disabled())
483 reboot_type = BOOT_EFI;
484
485 return 0;
486}
487core_initcall(reboot_init);
488
489static inline void kb_wait(void)
490{
491 int i;
492
493 for (i = 0; i < 0x10000; i++) {
494 if ((inb(0x64) & 0x02) == 0)
495 break;
496 udelay(2);
497 }
498}
499
500static void vmxoff_nmi(int cpu, struct pt_regs *regs)
501{
502 cpu_emergency_vmxoff();
503}
504
505/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
506static void emergency_vmx_disable_all(void)
507{
508 /* Just make sure we won't change CPUs while doing this */
509 local_irq_disable();
510
511 /*
512 * We need to disable VMX on all CPUs before rebooting, otherwise
513 * we risk hanging up the machine, because the CPU ignore INIT
514 * signals when VMX is enabled.
515 *
516 * We can't take any locks and we may be on an inconsistent
517 * state, so we use NMIs as IPIs to tell the other CPUs to disable
518 * VMX and halt.
519 *
520 * For safety, we will avoid running the nmi_shootdown_cpus()
521 * stuff unnecessarily, but we don't have a way to check
522 * if other CPUs have VMX enabled. So we will call it only if the
523 * CPU we are running on has VMX enabled.
524 *
525 * We will miss cases where VMX is not enabled on all CPUs. This
526 * shouldn't do much harm because KVM always enable VMX on all
527 * CPUs anyway. But we can miss it on the small window where KVM
528 * is still enabling VMX.
529 */
530 if (cpu_has_vmx() && cpu_vmx_enabled()) {
531 /* Disable VMX on this CPU. */
532 cpu_vmxoff();
533
534 /* Halt and disable VMX on the other CPUs */
535 nmi_shootdown_cpus(vmxoff_nmi);
536
537 }
538}
539
540
541void __attribute__((weak)) mach_reboot_fixups(void)
542{
543}
544
545/*
546 * To the best of our knowledge Windows compatible x86 hardware expects
547 * the following on reboot:
548 *
549 * 1) If the FADT has the ACPI reboot register flag set, try it
550 * 2) If still alive, write to the keyboard controller
551 * 3) If still alive, write to the ACPI reboot register again
552 * 4) If still alive, write to the keyboard controller again
553 * 5) If still alive, call the EFI runtime service to reboot
554 * 6) If no EFI runtime service, call the BIOS to do a reboot
555 *
556 * We default to following the same pattern. We also have
557 * two other reboot methods: 'triple fault' and 'PCI', which
558 * can be triggered via the reboot= kernel boot option or
559 * via quirks.
560 *
561 * This means that this function can never return, it can misbehave
562 * by not rebooting properly and hanging.
563 */
564static void native_machine_emergency_restart(void)
565{
566 int i;
567 int attempt = 0;
568 int orig_reboot_type = reboot_type;
569 unsigned short mode;
570
571 if (reboot_emergency)
572 emergency_vmx_disable_all();
573
574 tboot_shutdown(TB_SHUTDOWN_REBOOT);
575
576 /* Tell the BIOS if we want cold or warm reboot */
577 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
578 *((unsigned short *)__va(0x472)) = mode;
579
580 /*
581 * If an EFI capsule has been registered with the firmware then
582 * override the reboot= parameter.
583 */
584 if (efi_capsule_pending(NULL)) {
585 pr_info("EFI capsule is pending, forcing EFI reboot.\n");
586 reboot_type = BOOT_EFI;
587 }
588
589 for (;;) {
590 /* Could also try the reset bit in the Hammer NB */
591 switch (reboot_type) {
592 case BOOT_ACPI:
593 acpi_reboot();
594 reboot_type = BOOT_KBD;
595 break;
596
597 case BOOT_KBD:
598 mach_reboot_fixups(); /* For board specific fixups */
599
600 for (i = 0; i < 10; i++) {
601 kb_wait();
602 udelay(50);
603 outb(0xfe, 0x64); /* Pulse reset low */
604 udelay(50);
605 }
606 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
607 attempt = 1;
608 reboot_type = BOOT_ACPI;
609 } else {
610 reboot_type = BOOT_EFI;
611 }
612 break;
613
614 case BOOT_EFI:
615 efi_reboot(reboot_mode, NULL);
616 reboot_type = BOOT_BIOS;
617 break;
618
619 case BOOT_BIOS:
620 machine_real_restart(MRR_BIOS);
621
622 /* We're probably dead after this, but... */
623 reboot_type = BOOT_CF9_SAFE;
624 break;
625
626 case BOOT_CF9_FORCE:
627 port_cf9_safe = true;
628 /* Fall through */
629
630 case BOOT_CF9_SAFE:
631 if (port_cf9_safe) {
632 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E;
633 u8 cf9 = inb(0xcf9) & ~reboot_code;
634 outb(cf9|2, 0xcf9); /* Request hard reset */
635 udelay(50);
636 /* Actually do the reset */
637 outb(cf9|reboot_code, 0xcf9);
638 udelay(50);
639 }
640 reboot_type = BOOT_TRIPLE;
641 break;
642
643 case BOOT_TRIPLE:
644 idt_invalidate(NULL);
645 __asm__ __volatile__("int3");
646
647 /* We're probably dead after this, but... */
648 reboot_type = BOOT_KBD;
649 break;
650 }
651 }
652}
653
654void native_machine_shutdown(void)
655{
656 /* Stop the cpus and apics */
657#ifdef CONFIG_X86_IO_APIC
658 /*
659 * Disabling IO APIC before local APIC is a workaround for
660 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
661 * Specification Update". In this situation, interrupts that target
662 * a Logical Processor whose Local APIC is either in the process of
663 * being hardware disabled or software disabled are neither delivered
664 * nor discarded. When this erratum occurs, the processor may hang.
665 *
666 * Even without the erratum, it still makes sense to quiet IO APIC
667 * before disabling Local APIC.
668 */
669 clear_IO_APIC();
670#endif
671
672#ifdef CONFIG_SMP
673 /*
674 * Stop all of the others. Also disable the local irq to
675 * not receive the per-cpu timer interrupt which may trigger
676 * scheduler's load balance.
677 */
678 local_irq_disable();
679 stop_other_cpus();
680#endif
681
682 lapic_shutdown();
683 restore_boot_irq_mode();
684
685#ifdef CONFIG_HPET_TIMER
686 hpet_disable();
687#endif
688
689#ifdef CONFIG_X86_64
690 x86_platform.iommu_shutdown();
691#endif
692}
693
694static void __machine_emergency_restart(int emergency)
695{
696 reboot_emergency = emergency;
697 machine_ops.emergency_restart();
698}
699
700static void native_machine_restart(char *__unused)
701{
702 pr_notice("machine restart\n");
703
704 if (!reboot_force)
705 machine_shutdown();
706 __machine_emergency_restart(0);
707}
708
709static void native_machine_halt(void)
710{
711 /* Stop other cpus and apics */
712 machine_shutdown();
713
714 tboot_shutdown(TB_SHUTDOWN_HALT);
715
716 stop_this_cpu(NULL);
717}
718
719static void native_machine_power_off(void)
720{
721 if (pm_power_off) {
722 if (!reboot_force)
723 machine_shutdown();
724 pm_power_off();
725 }
726 /* A fallback in case there is no PM info available */
727 tboot_shutdown(TB_SHUTDOWN_HALT);
728}
729
730struct machine_ops machine_ops __ro_after_init = {
731 .power_off = native_machine_power_off,
732 .shutdown = native_machine_shutdown,
733 .emergency_restart = native_machine_emergency_restart,
734 .restart = native_machine_restart,
735 .halt = native_machine_halt,
736#ifdef CONFIG_KEXEC_CORE
737 .crash_shutdown = native_machine_crash_shutdown,
738#endif
739};
740
741void machine_power_off(void)
742{
743 machine_ops.power_off();
744}
745
746void machine_shutdown(void)
747{
748 machine_ops.shutdown();
749}
750
751void machine_emergency_restart(void)
752{
753 __machine_emergency_restart(1);
754}
755
756void machine_restart(char *cmd)
757{
758 machine_ops.restart(cmd);
759}
760
761void machine_halt(void)
762{
763 machine_ops.halt();
764}
765
766#ifdef CONFIG_KEXEC_CORE
767void machine_crash_shutdown(struct pt_regs *regs)
768{
769 machine_ops.crash_shutdown(regs);
770}
771#endif
772
773
774/* This is the CPU performing the emergency shutdown work. */
775int crashing_cpu = -1;
776
777#if defined(CONFIG_SMP)
778
779static nmi_shootdown_cb shootdown_callback;
780
781static atomic_t waiting_for_crash_ipi;
782static int crash_ipi_issued;
783
784static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
785{
786 int cpu;
787
788 cpu = raw_smp_processor_id();
789
790 /*
791 * Don't do anything if this handler is invoked on crashing cpu.
792 * Otherwise, system will completely hang. Crashing cpu can get
793 * an NMI if system was initially booted with nmi_watchdog parameter.
794 */
795 if (cpu == crashing_cpu)
796 return NMI_HANDLED;
797 local_irq_disable();
798
799 shootdown_callback(cpu, regs);
800
801 atomic_dec(&waiting_for_crash_ipi);
802 /* Assume hlt works */
803 halt();
804 for (;;)
805 cpu_relax();
806
807 return NMI_HANDLED;
808}
809
810static void smp_send_nmi_allbutself(void)
811{
812 apic->send_IPI_allbutself(NMI_VECTOR);
813}
814
815/*
816 * Halt all other CPUs, calling the specified function on each of them
817 *
818 * This function can be used to halt all other CPUs on crash
819 * or emergency reboot time. The function passed as parameter
820 * will be called inside a NMI handler on all CPUs.
821 */
822void nmi_shootdown_cpus(nmi_shootdown_cb callback)
823{
824 unsigned long msecs;
825 local_irq_disable();
826
827 /* Make a note of crashing cpu. Will be used in NMI callback. */
828 crashing_cpu = safe_smp_processor_id();
829
830 shootdown_callback = callback;
831
832 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
833 /* Would it be better to replace the trap vector here? */
834 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
835 NMI_FLAG_FIRST, "crash"))
836 return; /* Return what? */
837 /*
838 * Ensure the new callback function is set before sending
839 * out the NMI
840 */
841 wmb();
842
843 smp_send_nmi_allbutself();
844
845 /* Kick CPUs looping in NMI context. */
846 WRITE_ONCE(crash_ipi_issued, 1);
847
848 msecs = 1000; /* Wait at most a second for the other cpus to stop */
849 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
850 mdelay(1);
851 msecs--;
852 }
853
854 /* Leave the nmi callback set */
855}
856
857/*
858 * Check if the crash dumping IPI got issued and if so, call its callback
859 * directly. This function is used when we have already been in NMI handler.
860 * It doesn't return.
861 */
862void run_crash_ipi_callback(struct pt_regs *regs)
863{
864 if (crash_ipi_issued)
865 crash_nmi_callback(0, regs);
866}
867
868/* Override the weak function in kernel/panic.c */
869void nmi_panic_self_stop(struct pt_regs *regs)
870{
871 while (1) {
872 /* If no CPU is preparing crash dump, we simply loop here. */
873 run_crash_ipi_callback(regs);
874 cpu_relax();
875 }
876}
877
878#else /* !CONFIG_SMP */
879void nmi_shootdown_cpus(nmi_shootdown_cb callback)
880{
881 /* No other CPUs to shoot down */
882}
883
884void run_crash_ipi_callback(struct pt_regs *regs)
885{
886}
887#endif
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 <linux/delay.h>
10#include <acpi/reboot.h>
11#include <asm/io.h>
12#include <asm/apic.h>
13#include <asm/desc.h>
14#include <asm/hpet.h>
15#include <asm/pgtable.h>
16#include <asm/proto.h>
17#include <asm/reboot_fixups.h>
18#include <asm/reboot.h>
19#include <asm/pci_x86.h>
20#include <asm/virtext.h>
21#include <asm/cpu.h>
22#include <asm/nmi.h>
23
24#ifdef CONFIG_X86_32
25# include <linux/ctype.h>
26# include <linux/mc146818rtc.h>
27# include <asm/realmode.h>
28#else
29# include <asm/x86_init.h>
30#endif
31
32/*
33 * Power off function, if any
34 */
35void (*pm_power_off)(void);
36EXPORT_SYMBOL(pm_power_off);
37
38static const struct desc_ptr no_idt = {};
39static int reboot_mode;
40enum reboot_type reboot_type = BOOT_ACPI;
41int 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 */
50static int reboot_default = 1;
51
52#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
53static 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 */
61static int reboot_emergency;
62
63/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
64bool 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 (only for X86_32)
71 * smp Reboot by executing reset on BSP or other CPU (only for X86_32)
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 */
79static 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_X86_32
99#ifdef CONFIG_SMP
100 case 's':
101 if (isdigit(*(str+1))) {
102 reboot_cpu = (int) (*(str+1) - '0');
103 if (isdigit(*(str+2)))
104 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
105 }
106 /*
107 * We will leave sorting out the final value
108 * when we are ready to reboot, since we might not
109 * have detected BSP APIC ID or smp_num_cpu
110 */
111 break;
112#endif /* CONFIG_SMP */
113
114 case 'b':
115#endif
116 case 'a':
117 case 'k':
118 case 't':
119 case 'e':
120 case 'p':
121 reboot_type = *str;
122 break;
123
124 case 'f':
125 reboot_force = 1;
126 break;
127 }
128
129 str = strchr(str, ',');
130 if (str)
131 str++;
132 else
133 break;
134 }
135 return 1;
136}
137
138__setup("reboot=", reboot_setup);
139
140
141#ifdef CONFIG_X86_32
142/*
143 * Reboot options and system auto-detection code provided by
144 * Dell Inc. so their systems "just work". :-)
145 */
146
147/*
148 * Some machines require the "reboot=b" or "reboot=k" commandline options,
149 * this quirk makes that automatic.
150 */
151static int __init set_bios_reboot(const struct dmi_system_id *d)
152{
153 if (reboot_type != BOOT_BIOS) {
154 reboot_type = BOOT_BIOS;
155 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
156 }
157 return 0;
158}
159
160void machine_real_restart(unsigned int type)
161{
162 void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
163 real_mode_header->machine_real_restart_asm;
164
165 local_irq_disable();
166
167 /*
168 * Write zero to CMOS register number 0x0f, which the BIOS POST
169 * routine will recognize as telling it to do a proper reboot. (Well
170 * that's what this book in front of me says -- it may only apply to
171 * the Phoenix BIOS though, it's not clear). At the same time,
172 * disable NMIs by setting the top bit in the CMOS address register,
173 * as we're about to do peculiar things to the CPU. I'm not sure if
174 * `outb_p' is needed instead of just `outb'. Use it to be on the
175 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
176 */
177 spin_lock(&rtc_lock);
178 CMOS_WRITE(0x00, 0x8f);
179 spin_unlock(&rtc_lock);
180
181 /*
182 * Switch back to the initial page table.
183 */
184 load_cr3(initial_page_table);
185
186 /*
187 * Write 0x1234 to absolute memory location 0x472. The BIOS reads
188 * this on booting to tell it to "Bypass memory test (also warm
189 * boot)". This seems like a fairly standard thing that gets set by
190 * REBOOT.COM programs, and the previous reset routine did this
191 * too. */
192 *((unsigned short *)0x472) = reboot_mode;
193
194 /* Jump to the identity-mapped low memory code */
195 restart_lowmem(type);
196}
197#ifdef CONFIG_APM_MODULE
198EXPORT_SYMBOL(machine_real_restart);
199#endif
200
201#endif /* CONFIG_X86_32 */
202
203/*
204 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
205 */
206static int __init set_pci_reboot(const struct dmi_system_id *d)
207{
208 if (reboot_type != BOOT_CF9) {
209 reboot_type = BOOT_CF9;
210 printk(KERN_INFO "%s series board detected. "
211 "Selecting PCI-method for reboots.\n", d->ident);
212 }
213 return 0;
214}
215
216static int __init set_kbd_reboot(const struct dmi_system_id *d)
217{
218 if (reboot_type != BOOT_KBD) {
219 reboot_type = BOOT_KBD;
220 printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
221 }
222 return 0;
223}
224
225/*
226 * This is a single dmi_table handling all reboot quirks. Note that
227 * REBOOT_BIOS is only available for 32bit
228 */
229static struct dmi_system_id __initdata reboot_dmi_table[] = {
230#ifdef CONFIG_X86_32
231 { /* Handle problems with rebooting on Dell E520's */
232 .callback = set_bios_reboot,
233 .ident = "Dell E520",
234 .matches = {
235 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
236 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
237 },
238 },
239 { /* Handle problems with rebooting on Dell 1300's */
240 .callback = set_bios_reboot,
241 .ident = "Dell PowerEdge 1300",
242 .matches = {
243 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
244 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
245 },
246 },
247 { /* Handle problems with rebooting on Dell 300's */
248 .callback = set_bios_reboot,
249 .ident = "Dell PowerEdge 300",
250 .matches = {
251 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
252 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
253 },
254 },
255 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
256 .callback = set_bios_reboot,
257 .ident = "Dell OptiPlex 745",
258 .matches = {
259 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
260 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
261 },
262 },
263 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
264 .callback = set_bios_reboot,
265 .ident = "Dell OptiPlex 745",
266 .matches = {
267 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
268 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
269 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
270 },
271 },
272 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
273 .callback = set_bios_reboot,
274 .ident = "Dell OptiPlex 745",
275 .matches = {
276 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
277 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
278 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
279 },
280 },
281 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
282 .callback = set_bios_reboot,
283 .ident = "Dell OptiPlex 330",
284 .matches = {
285 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
286 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
287 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
288 },
289 },
290 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
291 .callback = set_bios_reboot,
292 .ident = "Dell OptiPlex 360",
293 .matches = {
294 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
295 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
296 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
297 },
298 },
299 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
300 .callback = set_bios_reboot,
301 .ident = "Dell OptiPlex 760",
302 .matches = {
303 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
304 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
305 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
306 },
307 },
308 { /* Handle problems with rebooting on Dell 2400's */
309 .callback = set_bios_reboot,
310 .ident = "Dell PowerEdge 2400",
311 .matches = {
312 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
313 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
314 },
315 },
316 { /* Handle problems with rebooting on Dell T5400's */
317 .callback = set_bios_reboot,
318 .ident = "Dell Precision T5400",
319 .matches = {
320 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
321 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
322 },
323 },
324 { /* Handle problems with rebooting on Dell T7400's */
325 .callback = set_bios_reboot,
326 .ident = "Dell Precision T7400",
327 .matches = {
328 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
329 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
330 },
331 },
332 { /* Handle problems with rebooting on HP laptops */
333 .callback = set_bios_reboot,
334 .ident = "HP Compaq Laptop",
335 .matches = {
336 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
337 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
338 },
339 },
340 { /* Handle problems with rebooting on Dell XPS710 */
341 .callback = set_bios_reboot,
342 .ident = "Dell XPS710",
343 .matches = {
344 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
345 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
346 },
347 },
348 { /* Handle problems with rebooting on Dell DXP061 */
349 .callback = set_bios_reboot,
350 .ident = "Dell DXP061",
351 .matches = {
352 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
353 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
354 },
355 },
356 { /* Handle problems with rebooting on Sony VGN-Z540N */
357 .callback = set_bios_reboot,
358 .ident = "Sony VGN-Z540N",
359 .matches = {
360 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
361 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
362 },
363 },
364 { /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
365 .callback = set_bios_reboot,
366 .ident = "CompuLab SBC-FITPC2",
367 .matches = {
368 DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
369 DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
370 },
371 },
372 { /* Handle problems with rebooting on ASUS P4S800 */
373 .callback = set_bios_reboot,
374 .ident = "ASUS P4S800",
375 .matches = {
376 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
377 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
378 },
379 },
380#endif /* CONFIG_X86_32 */
381
382 { /* Handle reboot issue on Acer Aspire one */
383 .callback = set_kbd_reboot,
384 .ident = "Acer Aspire One A110",
385 .matches = {
386 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
387 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
388 },
389 },
390 { /* Handle problems with rebooting on Apple MacBook5 */
391 .callback = set_pci_reboot,
392 .ident = "Apple MacBook5",
393 .matches = {
394 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
395 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
396 },
397 },
398 { /* Handle problems with rebooting on Apple MacBookPro5 */
399 .callback = set_pci_reboot,
400 .ident = "Apple MacBookPro5",
401 .matches = {
402 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
403 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
404 },
405 },
406 { /* Handle problems with rebooting on Apple Macmini3,1 */
407 .callback = set_pci_reboot,
408 .ident = "Apple Macmini3,1",
409 .matches = {
410 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
411 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
412 },
413 },
414 { /* Handle problems with rebooting on the iMac9,1. */
415 .callback = set_pci_reboot,
416 .ident = "Apple iMac9,1",
417 .matches = {
418 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
419 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
420 },
421 },
422 { /* Handle problems with rebooting on the Latitude E6320. */
423 .callback = set_pci_reboot,
424 .ident = "Dell Latitude E6320",
425 .matches = {
426 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
427 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
428 },
429 },
430 { /* Handle problems with rebooting on the Latitude E5420. */
431 .callback = set_pci_reboot,
432 .ident = "Dell Latitude E5420",
433 .matches = {
434 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
435 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
436 },
437 },
438 { /* Handle problems with rebooting on the Latitude E6420. */
439 .callback = set_pci_reboot,
440 .ident = "Dell Latitude E6420",
441 .matches = {
442 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
443 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
444 },
445 },
446 { /* Handle problems with rebooting on the OptiPlex 990. */
447 .callback = set_pci_reboot,
448 .ident = "Dell OptiPlex 990",
449 .matches = {
450 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
451 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
452 },
453 },
454 { /* Handle problems with rebooting on the Precision M6600. */
455 .callback = set_pci_reboot,
456 .ident = "Dell OptiPlex 990",
457 .matches = {
458 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
459 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
460 },
461 },
462 { }
463};
464
465static int __init reboot_init(void)
466{
467 /*
468 * Only do the DMI check if reboot_type hasn't been overridden
469 * on the command line
470 */
471 if (reboot_default)
472 dmi_check_system(reboot_dmi_table);
473 return 0;
474}
475core_initcall(reboot_init);
476
477static inline void kb_wait(void)
478{
479 int i;
480
481 for (i = 0; i < 0x10000; i++) {
482 if ((inb(0x64) & 0x02) == 0)
483 break;
484 udelay(2);
485 }
486}
487
488static void vmxoff_nmi(int cpu, struct pt_regs *regs)
489{
490 cpu_emergency_vmxoff();
491}
492
493/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
494static void emergency_vmx_disable_all(void)
495{
496 /* Just make sure we won't change CPUs while doing this */
497 local_irq_disable();
498
499 /*
500 * We need to disable VMX on all CPUs before rebooting, otherwise
501 * we risk hanging up the machine, because the CPU ignore INIT
502 * signals when VMX is enabled.
503 *
504 * We can't take any locks and we may be on an inconsistent
505 * state, so we use NMIs as IPIs to tell the other CPUs to disable
506 * VMX and halt.
507 *
508 * For safety, we will avoid running the nmi_shootdown_cpus()
509 * stuff unnecessarily, but we don't have a way to check
510 * if other CPUs have VMX enabled. So we will call it only if the
511 * CPU we are running on has VMX enabled.
512 *
513 * We will miss cases where VMX is not enabled on all CPUs. This
514 * shouldn't do much harm because KVM always enable VMX on all
515 * CPUs anyway. But we can miss it on the small window where KVM
516 * is still enabling VMX.
517 */
518 if (cpu_has_vmx() && cpu_vmx_enabled()) {
519 /* Disable VMX on this CPU. */
520 cpu_vmxoff();
521
522 /* Halt and disable VMX on the other CPUs */
523 nmi_shootdown_cpus(vmxoff_nmi);
524
525 }
526}
527
528
529void __attribute__((weak)) mach_reboot_fixups(void)
530{
531}
532
533/*
534 * Windows compatible x86 hardware expects the following on reboot:
535 *
536 * 1) If the FADT has the ACPI reboot register flag set, try it
537 * 2) If still alive, write to the keyboard controller
538 * 3) If still alive, write to the ACPI reboot register again
539 * 4) If still alive, write to the keyboard controller again
540 *
541 * If the machine is still alive at this stage, it gives up. We default to
542 * following the same pattern, except that if we're still alive after (4) we'll
543 * try to force a triple fault and then cycle between hitting the keyboard
544 * controller and doing that
545 */
546static void native_machine_emergency_restart(void)
547{
548 int i;
549 int attempt = 0;
550 int orig_reboot_type = reboot_type;
551
552 if (reboot_emergency)
553 emergency_vmx_disable_all();
554
555 tboot_shutdown(TB_SHUTDOWN_REBOOT);
556
557 /* Tell the BIOS if we want cold or warm reboot */
558 *((unsigned short *)__va(0x472)) = reboot_mode;
559
560 for (;;) {
561 /* Could also try the reset bit in the Hammer NB */
562 switch (reboot_type) {
563 case BOOT_KBD:
564 mach_reboot_fixups(); /* For board specific fixups */
565
566 for (i = 0; i < 10; i++) {
567 kb_wait();
568 udelay(50);
569 outb(0xfe, 0x64); /* Pulse reset low */
570 udelay(50);
571 }
572 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
573 attempt = 1;
574 reboot_type = BOOT_ACPI;
575 } else {
576 reboot_type = BOOT_TRIPLE;
577 }
578 break;
579
580 case BOOT_TRIPLE:
581 load_idt(&no_idt);
582 __asm__ __volatile__("int3");
583
584 reboot_type = BOOT_KBD;
585 break;
586
587#ifdef CONFIG_X86_32
588 case BOOT_BIOS:
589 machine_real_restart(MRR_BIOS);
590
591 reboot_type = BOOT_KBD;
592 break;
593#endif
594
595 case BOOT_ACPI:
596 acpi_reboot();
597 reboot_type = BOOT_KBD;
598 break;
599
600 case BOOT_EFI:
601 if (efi_enabled)
602 efi.reset_system(reboot_mode ?
603 EFI_RESET_WARM :
604 EFI_RESET_COLD,
605 EFI_SUCCESS, 0, NULL);
606 reboot_type = BOOT_KBD;
607 break;
608
609 case BOOT_CF9:
610 port_cf9_safe = true;
611 /* Fall through */
612
613 case BOOT_CF9_COND:
614 if (port_cf9_safe) {
615 u8 cf9 = inb(0xcf9) & ~6;
616 outb(cf9|2, 0xcf9); /* Request hard reset */
617 udelay(50);
618 outb(cf9|6, 0xcf9); /* Actually do the reset */
619 udelay(50);
620 }
621 reboot_type = BOOT_KBD;
622 break;
623 }
624 }
625}
626
627void native_machine_shutdown(void)
628{
629 /* Stop the cpus and apics */
630#ifdef CONFIG_SMP
631
632 /* The boot cpu is always logical cpu 0 */
633 int reboot_cpu_id = 0;
634
635#ifdef CONFIG_X86_32
636 /* See if there has been given a command line override */
637 if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
638 cpu_online(reboot_cpu))
639 reboot_cpu_id = reboot_cpu;
640#endif
641
642 /* Make certain the cpu I'm about to reboot on is online */
643 if (!cpu_online(reboot_cpu_id))
644 reboot_cpu_id = smp_processor_id();
645
646 /* Make certain I only run on the appropriate processor */
647 set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
648
649 /*
650 * O.K Now that I'm on the appropriate processor, stop all of the
651 * others. Also disable the local irq to not receive the per-cpu
652 * timer interrupt which may trigger scheduler's load balance.
653 */
654 local_irq_disable();
655 stop_other_cpus();
656#endif
657
658 lapic_shutdown();
659
660#ifdef CONFIG_X86_IO_APIC
661 disable_IO_APIC();
662#endif
663
664#ifdef CONFIG_HPET_TIMER
665 hpet_disable();
666#endif
667
668#ifdef CONFIG_X86_64
669 x86_platform.iommu_shutdown();
670#endif
671}
672
673static void __machine_emergency_restart(int emergency)
674{
675 reboot_emergency = emergency;
676 machine_ops.emergency_restart();
677}
678
679static void native_machine_restart(char *__unused)
680{
681 printk("machine restart\n");
682
683 if (!reboot_force)
684 machine_shutdown();
685 __machine_emergency_restart(0);
686}
687
688static void native_machine_halt(void)
689{
690 /* Stop other cpus and apics */
691 machine_shutdown();
692
693 tboot_shutdown(TB_SHUTDOWN_HALT);
694
695 stop_this_cpu(NULL);
696}
697
698static void native_machine_power_off(void)
699{
700 if (pm_power_off) {
701 if (!reboot_force)
702 machine_shutdown();
703 pm_power_off();
704 }
705 /* A fallback in case there is no PM info available */
706 tboot_shutdown(TB_SHUTDOWN_HALT);
707}
708
709struct machine_ops machine_ops = {
710 .power_off = native_machine_power_off,
711 .shutdown = native_machine_shutdown,
712 .emergency_restart = native_machine_emergency_restart,
713 .restart = native_machine_restart,
714 .halt = native_machine_halt,
715#ifdef CONFIG_KEXEC
716 .crash_shutdown = native_machine_crash_shutdown,
717#endif
718};
719
720void machine_power_off(void)
721{
722 machine_ops.power_off();
723}
724
725void machine_shutdown(void)
726{
727 machine_ops.shutdown();
728}
729
730void machine_emergency_restart(void)
731{
732 __machine_emergency_restart(1);
733}
734
735void machine_restart(char *cmd)
736{
737 machine_ops.restart(cmd);
738}
739
740void machine_halt(void)
741{
742 machine_ops.halt();
743}
744
745#ifdef CONFIG_KEXEC
746void machine_crash_shutdown(struct pt_regs *regs)
747{
748 machine_ops.crash_shutdown(regs);
749}
750#endif
751
752
753#if defined(CONFIG_SMP)
754
755/* This keeps a track of which one is crashing cpu. */
756static int crashing_cpu;
757static nmi_shootdown_cb shootdown_callback;
758
759static atomic_t waiting_for_crash_ipi;
760
761static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
762{
763 int cpu;
764
765 cpu = raw_smp_processor_id();
766
767 /*
768 * Don't do anything if this handler is invoked on crashing cpu.
769 * Otherwise, system will completely hang. Crashing cpu can get
770 * an NMI if system was initially booted with nmi_watchdog parameter.
771 */
772 if (cpu == crashing_cpu)
773 return NMI_HANDLED;
774 local_irq_disable();
775
776 shootdown_callback(cpu, regs);
777
778 atomic_dec(&waiting_for_crash_ipi);
779 /* Assume hlt works */
780 halt();
781 for (;;)
782 cpu_relax();
783
784 return NMI_HANDLED;
785}
786
787static void smp_send_nmi_allbutself(void)
788{
789 apic->send_IPI_allbutself(NMI_VECTOR);
790}
791
792/*
793 * Halt all other CPUs, calling the specified function on each of them
794 *
795 * This function can be used to halt all other CPUs on crash
796 * or emergency reboot time. The function passed as parameter
797 * will be called inside a NMI handler on all CPUs.
798 */
799void nmi_shootdown_cpus(nmi_shootdown_cb callback)
800{
801 unsigned long msecs;
802 local_irq_disable();
803
804 /* Make a note of crashing cpu. Will be used in NMI callback. */
805 crashing_cpu = safe_smp_processor_id();
806
807 shootdown_callback = callback;
808
809 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
810 /* Would it be better to replace the trap vector here? */
811 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
812 NMI_FLAG_FIRST, "crash"))
813 return; /* Return what? */
814 /*
815 * Ensure the new callback function is set before sending
816 * out the NMI
817 */
818 wmb();
819
820 smp_send_nmi_allbutself();
821
822 msecs = 1000; /* Wait at most a second for the other cpus to stop */
823 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
824 mdelay(1);
825 msecs--;
826 }
827
828 /* Leave the nmi callback set */
829}
830#else /* !CONFIG_SMP */
831void nmi_shootdown_cpus(nmi_shootdown_cb callback)
832{
833 /* No other CPUs to shoot down */
834}
835#endif