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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 <linux/pgtable.h>
15#include <acpi/reboot.h>
16#include <asm/io.h>
17#include <asm/apic.h>
18#include <asm/io_apic.h>
19#include <asm/desc.h>
20#include <asm/hpet.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
84/*
85 * Some machines don't handle the default ACPI reboot method and
86 * require the EFI reboot method:
87 */
88static int __init set_efi_reboot(const struct dmi_system_id *d)
89{
90 if (reboot_type != BOOT_EFI && !efi_runtime_disabled()) {
91 reboot_type = BOOT_EFI;
92 pr_info("%s series board detected. Selecting EFI-method for reboot.\n", d->ident);
93 }
94 return 0;
95}
96
97void __noreturn machine_real_restart(unsigned int type)
98{
99 local_irq_disable();
100
101 /*
102 * Write zero to CMOS register number 0x0f, which the BIOS POST
103 * routine will recognize as telling it to do a proper reboot. (Well
104 * that's what this book in front of me says -- it may only apply to
105 * the Phoenix BIOS though, it's not clear). At the same time,
106 * disable NMIs by setting the top bit in the CMOS address register,
107 * as we're about to do peculiar things to the CPU. I'm not sure if
108 * `outb_p' is needed instead of just `outb'. Use it to be on the
109 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
110 */
111 spin_lock(&rtc_lock);
112 CMOS_WRITE(0x00, 0x8f);
113 spin_unlock(&rtc_lock);
114
115 /*
116 * Switch back to the initial page table.
117 */
118#ifdef CONFIG_X86_32
119 load_cr3(initial_page_table);
120#else
121 write_cr3(real_mode_header->trampoline_pgd);
122
123 /* Exiting long mode will fail if CR4.PCIDE is set. */
124 if (boot_cpu_has(X86_FEATURE_PCID))
125 cr4_clear_bits(X86_CR4_PCIDE);
126#endif
127
128 /* Jump to the identity-mapped low memory code */
129#ifdef CONFIG_X86_32
130 asm volatile("jmpl *%0" : :
131 "rm" (real_mode_header->machine_real_restart_asm),
132 "a" (type));
133#else
134 asm volatile("ljmpl *%0" : :
135 "m" (real_mode_header->machine_real_restart_asm),
136 "D" (type));
137#endif
138 unreachable();
139}
140#ifdef CONFIG_APM_MODULE
141EXPORT_SYMBOL(machine_real_restart);
142#endif
143STACK_FRAME_NON_STANDARD(machine_real_restart);
144
145/*
146 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
147 */
148static int __init set_pci_reboot(const struct dmi_system_id *d)
149{
150 if (reboot_type != BOOT_CF9_FORCE) {
151 reboot_type = BOOT_CF9_FORCE;
152 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
153 d->ident, "PCI");
154 }
155 return 0;
156}
157
158static int __init set_kbd_reboot(const struct dmi_system_id *d)
159{
160 if (reboot_type != BOOT_KBD) {
161 reboot_type = BOOT_KBD;
162 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
163 d->ident, "KBD");
164 }
165 return 0;
166}
167
168/*
169 * This is a single dmi_table handling all reboot quirks.
170 */
171static const struct dmi_system_id reboot_dmi_table[] __initconst = {
172
173 /* Acer */
174 { /* Handle reboot issue on Acer Aspire one */
175 .callback = set_kbd_reboot,
176 .ident = "Acer Aspire One A110",
177 .matches = {
178 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
179 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
180 },
181 },
182 { /* Handle reboot issue on Acer TravelMate X514-51T */
183 .callback = set_efi_reboot,
184 .ident = "Acer TravelMate X514-51T",
185 .matches = {
186 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
187 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate X514-51T"),
188 },
189 },
190
191 /* Apple */
192 { /* Handle problems with rebooting on Apple MacBook5 */
193 .callback = set_pci_reboot,
194 .ident = "Apple MacBook5",
195 .matches = {
196 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
197 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
198 },
199 },
200 { /* Handle problems with rebooting on Apple MacBook6,1 */
201 .callback = set_pci_reboot,
202 .ident = "Apple MacBook6,1",
203 .matches = {
204 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
205 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"),
206 },
207 },
208 { /* Handle problems with rebooting on Apple MacBookPro5 */
209 .callback = set_pci_reboot,
210 .ident = "Apple MacBookPro5",
211 .matches = {
212 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
213 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
214 },
215 },
216 { /* Handle problems with rebooting on Apple Macmini3,1 */
217 .callback = set_pci_reboot,
218 .ident = "Apple Macmini3,1",
219 .matches = {
220 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
221 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
222 },
223 },
224 { /* Handle problems with rebooting on the iMac9,1. */
225 .callback = set_pci_reboot,
226 .ident = "Apple iMac9,1",
227 .matches = {
228 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
229 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
230 },
231 },
232 { /* Handle problems with rebooting on the iMac10,1. */
233 .callback = set_pci_reboot,
234 .ident = "Apple iMac10,1",
235 .matches = {
236 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
237 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
238 },
239 },
240
241 /* ASRock */
242 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
243 .callback = set_pci_reboot,
244 .ident = "ASRock Q1900DC-ITX",
245 .matches = {
246 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
247 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
248 },
249 },
250
251 /* ASUS */
252 { /* Handle problems with rebooting on ASUS P4S800 */
253 .callback = set_bios_reboot,
254 .ident = "ASUS P4S800",
255 .matches = {
256 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
257 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
258 },
259 },
260 { /* Handle problems with rebooting on ASUS EeeBook X205TA */
261 .callback = set_acpi_reboot,
262 .ident = "ASUS EeeBook X205TA",
263 .matches = {
264 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
265 DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"),
266 },
267 },
268 { /* Handle problems with rebooting on ASUS EeeBook X205TAW */
269 .callback = set_acpi_reboot,
270 .ident = "ASUS EeeBook X205TAW",
271 .matches = {
272 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
273 DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"),
274 },
275 },
276
277 /* Certec */
278 { /* Handle problems with rebooting on Certec BPC600 */
279 .callback = set_pci_reboot,
280 .ident = "Certec BPC600",
281 .matches = {
282 DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
283 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
284 },
285 },
286
287 /* Dell */
288 { /* Handle problems with rebooting on Dell DXP061 */
289 .callback = set_bios_reboot,
290 .ident = "Dell DXP061",
291 .matches = {
292 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
293 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
294 },
295 },
296 { /* Handle problems with rebooting on Dell E520's */
297 .callback = set_bios_reboot,
298 .ident = "Dell E520",
299 .matches = {
300 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
301 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
302 },
303 },
304 { /* Handle problems with rebooting on the Latitude E5410. */
305 .callback = set_pci_reboot,
306 .ident = "Dell Latitude E5410",
307 .matches = {
308 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
309 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
310 },
311 },
312 { /* Handle problems with rebooting on the Latitude E5420. */
313 .callback = set_pci_reboot,
314 .ident = "Dell Latitude E5420",
315 .matches = {
316 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
317 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
318 },
319 },
320 { /* Handle problems with rebooting on the Latitude E6320. */
321 .callback = set_pci_reboot,
322 .ident = "Dell Latitude E6320",
323 .matches = {
324 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
325 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
326 },
327 },
328 { /* Handle problems with rebooting on the Latitude E6420. */
329 .callback = set_pci_reboot,
330 .ident = "Dell Latitude E6420",
331 .matches = {
332 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
333 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
334 },
335 },
336 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
337 .callback = set_bios_reboot,
338 .ident = "Dell OptiPlex 330",
339 .matches = {
340 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
341 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
342 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
343 },
344 },
345 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
346 .callback = set_bios_reboot,
347 .ident = "Dell OptiPlex 360",
348 .matches = {
349 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
350 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
351 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
352 },
353 },
354 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
355 .callback = set_bios_reboot,
356 .ident = "Dell OptiPlex 745",
357 .matches = {
358 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
359 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
360 },
361 },
362 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
363 .callback = set_bios_reboot,
364 .ident = "Dell OptiPlex 745",
365 .matches = {
366 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
367 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
368 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
369 },
370 },
371 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
372 .callback = set_bios_reboot,
373 .ident = "Dell OptiPlex 745",
374 .matches = {
375 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
376 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
377 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
378 },
379 },
380 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
381 .callback = set_bios_reboot,
382 .ident = "Dell OptiPlex 760",
383 .matches = {
384 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
385 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
386 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
387 },
388 },
389 { /* Handle problems with rebooting on the OptiPlex 990. */
390 .callback = set_pci_reboot,
391 .ident = "Dell OptiPlex 990",
392 .matches = {
393 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
394 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
395 },
396 },
397 { /* Handle problems with rebooting on Dell 300's */
398 .callback = set_bios_reboot,
399 .ident = "Dell PowerEdge 300",
400 .matches = {
401 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
402 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
403 },
404 },
405 { /* Handle problems with rebooting on Dell 1300's */
406 .callback = set_bios_reboot,
407 .ident = "Dell PowerEdge 1300",
408 .matches = {
409 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
410 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
411 },
412 },
413 { /* Handle problems with rebooting on Dell 2400's */
414 .callback = set_bios_reboot,
415 .ident = "Dell PowerEdge 2400",
416 .matches = {
417 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
418 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
419 },
420 },
421 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
422 .callback = set_pci_reboot,
423 .ident = "Dell PowerEdge C6100",
424 .matches = {
425 DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
426 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
427 },
428 },
429 { /* Handle problems with rebooting on the Precision M6600. */
430 .callback = set_pci_reboot,
431 .ident = "Dell Precision M6600",
432 .matches = {
433 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
434 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
435 },
436 },
437 { /* Handle problems with rebooting on Dell T5400's */
438 .callback = set_bios_reboot,
439 .ident = "Dell Precision T5400",
440 .matches = {
441 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
442 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
443 },
444 },
445 { /* Handle problems with rebooting on Dell T7400's */
446 .callback = set_bios_reboot,
447 .ident = "Dell Precision T7400",
448 .matches = {
449 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
450 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
451 },
452 },
453 { /* Handle problems with rebooting on Dell XPS710 */
454 .callback = set_bios_reboot,
455 .ident = "Dell XPS710",
456 .matches = {
457 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
458 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
459 },
460 },
461 { /* Handle problems with rebooting on Dell Optiplex 7450 AIO */
462 .callback = set_acpi_reboot,
463 .ident = "Dell OptiPlex 7450 AIO",
464 .matches = {
465 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
466 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"),
467 },
468 },
469
470 /* Hewlett-Packard */
471 { /* Handle problems with rebooting on HP laptops */
472 .callback = set_bios_reboot,
473 .ident = "HP Compaq Laptop",
474 .matches = {
475 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
476 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
477 },
478 },
479
480 /* Sony */
481 { /* Handle problems with rebooting on Sony VGN-Z540N */
482 .callback = set_bios_reboot,
483 .ident = "Sony VGN-Z540N",
484 .matches = {
485 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
486 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
487 },
488 },
489
490 { }
491};
492
493static int __init reboot_init(void)
494{
495 int rv;
496
497 /*
498 * Only do the DMI check if reboot_type hasn't been overridden
499 * on the command line
500 */
501 if (!reboot_default)
502 return 0;
503
504 /*
505 * The DMI quirks table takes precedence. If no quirks entry
506 * matches and the ACPI Hardware Reduced bit is set and EFI
507 * runtime services are enabled, force EFI reboot.
508 */
509 rv = dmi_check_system(reboot_dmi_table);
510
511 if (!rv && efi_reboot_required() && !efi_runtime_disabled())
512 reboot_type = BOOT_EFI;
513
514 return 0;
515}
516core_initcall(reboot_init);
517
518static inline void kb_wait(void)
519{
520 int i;
521
522 for (i = 0; i < 0x10000; i++) {
523 if ((inb(0x64) & 0x02) == 0)
524 break;
525 udelay(2);
526 }
527}
528
529static void vmxoff_nmi(int cpu, struct pt_regs *regs)
530{
531 cpu_emergency_vmxoff();
532}
533
534/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
535static void emergency_vmx_disable_all(void)
536{
537 /* Just make sure we won't change CPUs while doing this */
538 local_irq_disable();
539
540 /*
541 * We need to disable VMX on all CPUs before rebooting, otherwise
542 * we risk hanging up the machine, because the CPU ignores INIT
543 * signals when VMX is enabled.
544 *
545 * We can't take any locks and we may be on an inconsistent
546 * state, so we use NMIs as IPIs to tell the other CPUs to disable
547 * VMX and halt.
548 *
549 * For safety, we will avoid running the nmi_shootdown_cpus()
550 * stuff unnecessarily, but we don't have a way to check
551 * if other CPUs have VMX enabled. So we will call it only if the
552 * CPU we are running on has VMX enabled.
553 *
554 * We will miss cases where VMX is not enabled on all CPUs. This
555 * shouldn't do much harm because KVM always enable VMX on all
556 * CPUs anyway. But we can miss it on the small window where KVM
557 * is still enabling VMX.
558 */
559 if (cpu_has_vmx() && cpu_vmx_enabled()) {
560 /* Disable VMX on this CPU. */
561 cpu_vmxoff();
562
563 /* Halt and disable VMX on the other CPUs */
564 nmi_shootdown_cpus(vmxoff_nmi);
565
566 }
567}
568
569
570void __attribute__((weak)) mach_reboot_fixups(void)
571{
572}
573
574/*
575 * To the best of our knowledge Windows compatible x86 hardware expects
576 * the following on reboot:
577 *
578 * 1) If the FADT has the ACPI reboot register flag set, try it
579 * 2) If still alive, write to the keyboard controller
580 * 3) If still alive, write to the ACPI reboot register again
581 * 4) If still alive, write to the keyboard controller again
582 * 5) If still alive, call the EFI runtime service to reboot
583 * 6) If no EFI runtime service, call the BIOS to do a reboot
584 *
585 * We default to following the same pattern. We also have
586 * two other reboot methods: 'triple fault' and 'PCI', which
587 * can be triggered via the reboot= kernel boot option or
588 * via quirks.
589 *
590 * This means that this function can never return, it can misbehave
591 * by not rebooting properly and hanging.
592 */
593static void native_machine_emergency_restart(void)
594{
595 int i;
596 int attempt = 0;
597 int orig_reboot_type = reboot_type;
598 unsigned short mode;
599
600 if (reboot_emergency)
601 emergency_vmx_disable_all();
602
603 tboot_shutdown(TB_SHUTDOWN_REBOOT);
604
605 /* Tell the BIOS if we want cold or warm reboot */
606 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
607 *((unsigned short *)__va(0x472)) = mode;
608
609 /*
610 * If an EFI capsule has been registered with the firmware then
611 * override the reboot= parameter.
612 */
613 if (efi_capsule_pending(NULL)) {
614 pr_info("EFI capsule is pending, forcing EFI reboot.\n");
615 reboot_type = BOOT_EFI;
616 }
617
618 for (;;) {
619 /* Could also try the reset bit in the Hammer NB */
620 switch (reboot_type) {
621 case BOOT_ACPI:
622 acpi_reboot();
623 reboot_type = BOOT_KBD;
624 break;
625
626 case BOOT_KBD:
627 mach_reboot_fixups(); /* For board specific fixups */
628
629 for (i = 0; i < 10; i++) {
630 kb_wait();
631 udelay(50);
632 outb(0xfe, 0x64); /* Pulse reset low */
633 udelay(50);
634 }
635 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
636 attempt = 1;
637 reboot_type = BOOT_ACPI;
638 } else {
639 reboot_type = BOOT_EFI;
640 }
641 break;
642
643 case BOOT_EFI:
644 efi_reboot(reboot_mode, NULL);
645 reboot_type = BOOT_BIOS;
646 break;
647
648 case BOOT_BIOS:
649 machine_real_restart(MRR_BIOS);
650
651 /* We're probably dead after this, but... */
652 reboot_type = BOOT_CF9_SAFE;
653 break;
654
655 case BOOT_CF9_FORCE:
656 port_cf9_safe = true;
657 fallthrough;
658
659 case BOOT_CF9_SAFE:
660 if (port_cf9_safe) {
661 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E;
662 u8 cf9 = inb(0xcf9) & ~reboot_code;
663 outb(cf9|2, 0xcf9); /* Request hard reset */
664 udelay(50);
665 /* Actually do the reset */
666 outb(cf9|reboot_code, 0xcf9);
667 udelay(50);
668 }
669 reboot_type = BOOT_TRIPLE;
670 break;
671
672 case BOOT_TRIPLE:
673 idt_invalidate(NULL);
674 __asm__ __volatile__("int3");
675
676 /* We're probably dead after this, but... */
677 reboot_type = BOOT_KBD;
678 break;
679 }
680 }
681}
682
683void native_machine_shutdown(void)
684{
685 /* Stop the cpus and apics */
686#ifdef CONFIG_X86_IO_APIC
687 /*
688 * Disabling IO APIC before local APIC is a workaround for
689 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
690 * Specification Update". In this situation, interrupts that target
691 * a Logical Processor whose Local APIC is either in the process of
692 * being hardware disabled or software disabled are neither delivered
693 * nor discarded. When this erratum occurs, the processor may hang.
694 *
695 * Even without the erratum, it still makes sense to quiet IO APIC
696 * before disabling Local APIC.
697 */
698 clear_IO_APIC();
699#endif
700
701#ifdef CONFIG_SMP
702 /*
703 * Stop all of the others. Also disable the local irq to
704 * not receive the per-cpu timer interrupt which may trigger
705 * scheduler's load balance.
706 */
707 local_irq_disable();
708 stop_other_cpus();
709#endif
710
711 lapic_shutdown();
712 restore_boot_irq_mode();
713
714#ifdef CONFIG_HPET_TIMER
715 hpet_disable();
716#endif
717
718#ifdef CONFIG_X86_64
719 x86_platform.iommu_shutdown();
720#endif
721}
722
723static void __machine_emergency_restart(int emergency)
724{
725 reboot_emergency = emergency;
726 machine_ops.emergency_restart();
727}
728
729static void native_machine_restart(char *__unused)
730{
731 pr_notice("machine restart\n");
732
733 if (!reboot_force)
734 machine_shutdown();
735 __machine_emergency_restart(0);
736}
737
738static void native_machine_halt(void)
739{
740 /* Stop other cpus and apics */
741 machine_shutdown();
742
743 tboot_shutdown(TB_SHUTDOWN_HALT);
744
745 stop_this_cpu(NULL);
746}
747
748static void native_machine_power_off(void)
749{
750 if (pm_power_off) {
751 if (!reboot_force)
752 machine_shutdown();
753 pm_power_off();
754 }
755 /* A fallback in case there is no PM info available */
756 tboot_shutdown(TB_SHUTDOWN_HALT);
757}
758
759struct machine_ops machine_ops __ro_after_init = {
760 .power_off = native_machine_power_off,
761 .shutdown = native_machine_shutdown,
762 .emergency_restart = native_machine_emergency_restart,
763 .restart = native_machine_restart,
764 .halt = native_machine_halt,
765#ifdef CONFIG_KEXEC_CORE
766 .crash_shutdown = native_machine_crash_shutdown,
767#endif
768};
769
770void machine_power_off(void)
771{
772 machine_ops.power_off();
773}
774
775void machine_shutdown(void)
776{
777 machine_ops.shutdown();
778}
779
780void machine_emergency_restart(void)
781{
782 __machine_emergency_restart(1);
783}
784
785void machine_restart(char *cmd)
786{
787 machine_ops.restart(cmd);
788}
789
790void machine_halt(void)
791{
792 machine_ops.halt();
793}
794
795#ifdef CONFIG_KEXEC_CORE
796void machine_crash_shutdown(struct pt_regs *regs)
797{
798 machine_ops.crash_shutdown(regs);
799}
800#endif
801
802
803/* This is the CPU performing the emergency shutdown work. */
804int crashing_cpu = -1;
805
806#if defined(CONFIG_SMP)
807
808static nmi_shootdown_cb shootdown_callback;
809
810static atomic_t waiting_for_crash_ipi;
811static int crash_ipi_issued;
812
813static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
814{
815 int cpu;
816
817 cpu = raw_smp_processor_id();
818
819 /*
820 * Don't do anything if this handler is invoked on crashing cpu.
821 * Otherwise, system will completely hang. Crashing cpu can get
822 * an NMI if system was initially booted with nmi_watchdog parameter.
823 */
824 if (cpu == crashing_cpu)
825 return NMI_HANDLED;
826 local_irq_disable();
827
828 shootdown_callback(cpu, regs);
829
830 atomic_dec(&waiting_for_crash_ipi);
831 /* Assume hlt works */
832 halt();
833 for (;;)
834 cpu_relax();
835
836 return NMI_HANDLED;
837}
838
839/*
840 * Halt all other CPUs, calling the specified function on each of them
841 *
842 * This function can be used to halt all other CPUs on crash
843 * or emergency reboot time. The function passed as parameter
844 * will be called inside a NMI handler on all CPUs.
845 */
846void nmi_shootdown_cpus(nmi_shootdown_cb callback)
847{
848 unsigned long msecs;
849 local_irq_disable();
850
851 /* Make a note of crashing cpu. Will be used in NMI callback. */
852 crashing_cpu = safe_smp_processor_id();
853
854 shootdown_callback = callback;
855
856 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
857 /* Would it be better to replace the trap vector here? */
858 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
859 NMI_FLAG_FIRST, "crash"))
860 return; /* Return what? */
861 /*
862 * Ensure the new callback function is set before sending
863 * out the NMI
864 */
865 wmb();
866
867 apic_send_IPI_allbutself(NMI_VECTOR);
868
869 /* Kick CPUs looping in NMI context. */
870 WRITE_ONCE(crash_ipi_issued, 1);
871
872 msecs = 1000; /* Wait at most a second for the other cpus to stop */
873 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
874 mdelay(1);
875 msecs--;
876 }
877
878 /* Leave the nmi callback set */
879}
880
881/*
882 * Check if the crash dumping IPI got issued and if so, call its callback
883 * directly. This function is used when we have already been in NMI handler.
884 * It doesn't return.
885 */
886void run_crash_ipi_callback(struct pt_regs *regs)
887{
888 if (crash_ipi_issued)
889 crash_nmi_callback(0, regs);
890}
891
892/* Override the weak function in kernel/panic.c */
893void nmi_panic_self_stop(struct pt_regs *regs)
894{
895 while (1) {
896 /* If no CPU is preparing crash dump, we simply loop here. */
897 run_crash_ipi_callback(regs);
898 cpu_relax();
899 }
900}
901
902#else /* !CONFIG_SMP */
903void nmi_shootdown_cpus(nmi_shootdown_cb callback)
904{
905 /* No other CPUs to shoot down */
906}
907
908void run_crash_ipi_callback(struct pt_regs *regs)
909{
910}
911#endif
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/objtool.h>
14#include <linux/pgtable.h>
15#include <acpi/reboot.h>
16#include <asm/io.h>
17#include <asm/apic.h>
18#include <asm/io_apic.h>
19#include <asm/desc.h>
20#include <asm/hpet.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/cpu.h>
26#include <asm/nmi.h>
27#include <asm/smp.h>
28
29#include <linux/ctype.h>
30#include <linux/mc146818rtc.h>
31#include <asm/realmode.h>
32#include <asm/x86_init.h>
33#include <asm/efi.h>
34
35/*
36 * Power off function, if any
37 */
38void (*pm_power_off)(void);
39EXPORT_SYMBOL(pm_power_off);
40
41/*
42 * This is set if we need to go through the 'emergency' path.
43 * When machine_emergency_restart() is called, we may be on
44 * an inconsistent state and won't be able to do a clean cleanup
45 */
46static int reboot_emergency;
47
48/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
49bool port_cf9_safe = false;
50
51/*
52 * Reboot options and system auto-detection code provided by
53 * Dell Inc. so their systems "just work". :-)
54 */
55
56/*
57 * Some machines require the "reboot=a" commandline options
58 */
59static int __init set_acpi_reboot(const struct dmi_system_id *d)
60{
61 if (reboot_type != BOOT_ACPI) {
62 reboot_type = BOOT_ACPI;
63 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
64 d->ident, "ACPI");
65 }
66 return 0;
67}
68
69/*
70 * Some machines require the "reboot=b" or "reboot=k" commandline options,
71 * this quirk makes that automatic.
72 */
73static int __init set_bios_reboot(const struct dmi_system_id *d)
74{
75 if (reboot_type != BOOT_BIOS) {
76 reboot_type = BOOT_BIOS;
77 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
78 d->ident, "BIOS");
79 }
80 return 0;
81}
82
83/*
84 * Some machines don't handle the default ACPI reboot method and
85 * require the EFI reboot method:
86 */
87static int __init set_efi_reboot(const struct dmi_system_id *d)
88{
89 if (reboot_type != BOOT_EFI && !efi_runtime_disabled()) {
90 reboot_type = BOOT_EFI;
91 pr_info("%s series board detected. Selecting EFI-method for reboot.\n", d->ident);
92 }
93 return 0;
94}
95
96void __noreturn machine_real_restart(unsigned int type)
97{
98 local_irq_disable();
99
100 /*
101 * Write zero to CMOS register number 0x0f, which the BIOS POST
102 * routine will recognize as telling it to do a proper reboot. (Well
103 * that's what this book in front of me says -- it may only apply to
104 * the Phoenix BIOS though, it's not clear). At the same time,
105 * disable NMIs by setting the top bit in the CMOS address register,
106 * as we're about to do peculiar things to the CPU. I'm not sure if
107 * `outb_p' is needed instead of just `outb'. Use it to be on the
108 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
109 */
110 spin_lock(&rtc_lock);
111 CMOS_WRITE(0x00, 0x8f);
112 spin_unlock(&rtc_lock);
113
114 /*
115 * Switch to the trampoline page table.
116 */
117 load_trampoline_pgtable();
118
119 /* Jump to the identity-mapped low memory code */
120#ifdef CONFIG_X86_32
121 asm volatile("jmpl *%0" : :
122 "rm" (real_mode_header->machine_real_restart_asm),
123 "a" (type));
124#else
125 asm volatile("ljmpl *%0" : :
126 "m" (real_mode_header->machine_real_restart_asm),
127 "D" (type));
128#endif
129 unreachable();
130}
131#ifdef CONFIG_APM_MODULE
132EXPORT_SYMBOL(machine_real_restart);
133#endif
134STACK_FRAME_NON_STANDARD(machine_real_restart);
135
136/*
137 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
138 */
139static int __init set_pci_reboot(const struct dmi_system_id *d)
140{
141 if (reboot_type != BOOT_CF9_FORCE) {
142 reboot_type = BOOT_CF9_FORCE;
143 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
144 d->ident, "PCI");
145 }
146 return 0;
147}
148
149static int __init set_kbd_reboot(const struct dmi_system_id *d)
150{
151 if (reboot_type != BOOT_KBD) {
152 reboot_type = BOOT_KBD;
153 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
154 d->ident, "KBD");
155 }
156 return 0;
157}
158
159/*
160 * This is a single dmi_table handling all reboot quirks.
161 */
162static const struct dmi_system_id reboot_dmi_table[] __initconst = {
163
164 /* Acer */
165 { /* Handle reboot issue on Acer Aspire one */
166 .callback = set_kbd_reboot,
167 .ident = "Acer Aspire One A110",
168 .matches = {
169 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
170 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
171 },
172 },
173 { /* Handle reboot issue on Acer TravelMate X514-51T */
174 .callback = set_efi_reboot,
175 .ident = "Acer TravelMate X514-51T",
176 .matches = {
177 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
178 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate X514-51T"),
179 },
180 },
181
182 /* Apple */
183 { /* Handle problems with rebooting on Apple MacBook5 */
184 .callback = set_pci_reboot,
185 .ident = "Apple MacBook5",
186 .matches = {
187 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
188 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
189 },
190 },
191 { /* Handle problems with rebooting on Apple MacBook6,1 */
192 .callback = set_pci_reboot,
193 .ident = "Apple MacBook6,1",
194 .matches = {
195 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
196 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"),
197 },
198 },
199 { /* Handle problems with rebooting on Apple MacBookPro5 */
200 .callback = set_pci_reboot,
201 .ident = "Apple MacBookPro5",
202 .matches = {
203 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
204 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
205 },
206 },
207 { /* Handle problems with rebooting on Apple Macmini3,1 */
208 .callback = set_pci_reboot,
209 .ident = "Apple Macmini3,1",
210 .matches = {
211 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
212 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
213 },
214 },
215 { /* Handle problems with rebooting on the iMac9,1. */
216 .callback = set_pci_reboot,
217 .ident = "Apple iMac9,1",
218 .matches = {
219 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
220 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
221 },
222 },
223 { /* Handle problems with rebooting on the iMac10,1. */
224 .callback = set_pci_reboot,
225 .ident = "Apple iMac10,1",
226 .matches = {
227 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
228 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
229 },
230 },
231
232 /* ASRock */
233 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
234 .callback = set_pci_reboot,
235 .ident = "ASRock Q1900DC-ITX",
236 .matches = {
237 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
238 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
239 },
240 },
241
242 /* ASUS */
243 { /* Handle problems with rebooting on ASUS P4S800 */
244 .callback = set_bios_reboot,
245 .ident = "ASUS P4S800",
246 .matches = {
247 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
248 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
249 },
250 },
251 { /* Handle problems with rebooting on ASUS EeeBook X205TA */
252 .callback = set_acpi_reboot,
253 .ident = "ASUS EeeBook X205TA",
254 .matches = {
255 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
256 DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"),
257 },
258 },
259 { /* Handle problems with rebooting on ASUS EeeBook X205TAW */
260 .callback = set_acpi_reboot,
261 .ident = "ASUS EeeBook X205TAW",
262 .matches = {
263 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
264 DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"),
265 },
266 },
267
268 /* Certec */
269 { /* Handle problems with rebooting on Certec BPC600 */
270 .callback = set_pci_reboot,
271 .ident = "Certec BPC600",
272 .matches = {
273 DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
274 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
275 },
276 },
277
278 /* Dell */
279 { /* Handle problems with rebooting on Dell DXP061 */
280 .callback = set_bios_reboot,
281 .ident = "Dell DXP061",
282 .matches = {
283 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
284 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
285 },
286 },
287 { /* Handle problems with rebooting on Dell E520's */
288 .callback = set_bios_reboot,
289 .ident = "Dell E520",
290 .matches = {
291 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
292 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
293 },
294 },
295 { /* Handle problems with rebooting on the Latitude E5410. */
296 .callback = set_pci_reboot,
297 .ident = "Dell Latitude E5410",
298 .matches = {
299 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
300 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
301 },
302 },
303 { /* Handle problems with rebooting on the Latitude E5420. */
304 .callback = set_pci_reboot,
305 .ident = "Dell Latitude E5420",
306 .matches = {
307 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
308 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
309 },
310 },
311 { /* Handle problems with rebooting on the Latitude E6320. */
312 .callback = set_pci_reboot,
313 .ident = "Dell Latitude E6320",
314 .matches = {
315 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
316 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
317 },
318 },
319 { /* Handle problems with rebooting on the Latitude E6420. */
320 .callback = set_pci_reboot,
321 .ident = "Dell Latitude E6420",
322 .matches = {
323 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
324 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
325 },
326 },
327 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
328 .callback = set_bios_reboot,
329 .ident = "Dell OptiPlex 330",
330 .matches = {
331 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
332 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
333 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
334 },
335 },
336 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
337 .callback = set_bios_reboot,
338 .ident = "Dell OptiPlex 360",
339 .matches = {
340 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
341 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
342 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
343 },
344 },
345 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
346 .callback = set_bios_reboot,
347 .ident = "Dell OptiPlex 745",
348 .matches = {
349 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
350 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
351 },
352 },
353 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
354 .callback = set_bios_reboot,
355 .ident = "Dell OptiPlex 745",
356 .matches = {
357 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
358 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
359 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
360 },
361 },
362 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
363 .callback = set_bios_reboot,
364 .ident = "Dell OptiPlex 745",
365 .matches = {
366 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
367 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
368 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
369 },
370 },
371 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
372 .callback = set_bios_reboot,
373 .ident = "Dell OptiPlex 760",
374 .matches = {
375 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
376 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
377 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
378 },
379 },
380 { /* Handle problems with rebooting on the OptiPlex 990. */
381 .callback = set_pci_reboot,
382 .ident = "Dell OptiPlex 990 BIOS A0x",
383 .matches = {
384 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
385 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
386 DMI_MATCH(DMI_BIOS_VERSION, "A0"),
387 },
388 },
389 { /* Handle problems with rebooting on Dell 300's */
390 .callback = set_bios_reboot,
391 .ident = "Dell PowerEdge 300",
392 .matches = {
393 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
394 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
395 },
396 },
397 { /* Handle problems with rebooting on Dell 1300's */
398 .callback = set_bios_reboot,
399 .ident = "Dell PowerEdge 1300",
400 .matches = {
401 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
402 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
403 },
404 },
405 { /* Handle problems with rebooting on Dell 2400's */
406 .callback = set_bios_reboot,
407 .ident = "Dell PowerEdge 2400",
408 .matches = {
409 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
410 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
411 },
412 },
413 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
414 .callback = set_pci_reboot,
415 .ident = "Dell PowerEdge C6100",
416 .matches = {
417 DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
418 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
419 },
420 },
421 { /* Handle problems with rebooting on the Precision M6600. */
422 .callback = set_pci_reboot,
423 .ident = "Dell Precision M6600",
424 .matches = {
425 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
426 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
427 },
428 },
429 { /* Handle problems with rebooting on Dell T5400's */
430 .callback = set_bios_reboot,
431 .ident = "Dell Precision T5400",
432 .matches = {
433 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
434 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
435 },
436 },
437 { /* Handle problems with rebooting on Dell T7400's */
438 .callback = set_bios_reboot,
439 .ident = "Dell Precision T7400",
440 .matches = {
441 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
442 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
443 },
444 },
445 { /* Handle problems with rebooting on Dell XPS710 */
446 .callback = set_bios_reboot,
447 .ident = "Dell XPS710",
448 .matches = {
449 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
450 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
451 },
452 },
453 { /* Handle problems with rebooting on Dell Optiplex 7450 AIO */
454 .callback = set_acpi_reboot,
455 .ident = "Dell OptiPlex 7450 AIO",
456 .matches = {
457 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
458 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"),
459 },
460 },
461
462 /* Hewlett-Packard */
463 { /* Handle problems with rebooting on HP laptops */
464 .callback = set_bios_reboot,
465 .ident = "HP Compaq Laptop",
466 .matches = {
467 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
468 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
469 },
470 },
471
472 { /* PCIe Wifi card isn't detected after reboot otherwise */
473 .callback = set_pci_reboot,
474 .ident = "Zotac ZBOX CI327 nano",
475 .matches = {
476 DMI_MATCH(DMI_SYS_VENDOR, "NA"),
477 DMI_MATCH(DMI_PRODUCT_NAME, "ZBOX-CI327NANO-GS-01"),
478 },
479 },
480
481 /* Sony */
482 { /* Handle problems with rebooting on Sony VGN-Z540N */
483 .callback = set_bios_reboot,
484 .ident = "Sony VGN-Z540N",
485 .matches = {
486 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
487 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
488 },
489 },
490
491 { }
492};
493
494static int __init reboot_init(void)
495{
496 int rv;
497
498 /*
499 * Only do the DMI check if reboot_type hasn't been overridden
500 * on the command line
501 */
502 if (!reboot_default)
503 return 0;
504
505 /*
506 * The DMI quirks table takes precedence. If no quirks entry
507 * matches and the ACPI Hardware Reduced bit is set and EFI
508 * runtime services are enabled, force EFI reboot.
509 */
510 rv = dmi_check_system(reboot_dmi_table);
511
512 if (!rv && efi_reboot_required() && !efi_runtime_disabled())
513 reboot_type = BOOT_EFI;
514
515 return 0;
516}
517core_initcall(reboot_init);
518
519static inline void kb_wait(void)
520{
521 int i;
522
523 for (i = 0; i < 0x10000; i++) {
524 if ((inb(0x64) & 0x02) == 0)
525 break;
526 udelay(2);
527 }
528}
529
530static inline void nmi_shootdown_cpus_on_restart(void);
531
532#if IS_ENABLED(CONFIG_KVM_INTEL) || IS_ENABLED(CONFIG_KVM_AMD)
533/* RCU-protected callback to disable virtualization prior to reboot. */
534static cpu_emergency_virt_cb __rcu *cpu_emergency_virt_callback;
535
536void cpu_emergency_register_virt_callback(cpu_emergency_virt_cb *callback)
537{
538 if (WARN_ON_ONCE(rcu_access_pointer(cpu_emergency_virt_callback)))
539 return;
540
541 rcu_assign_pointer(cpu_emergency_virt_callback, callback);
542}
543EXPORT_SYMBOL_GPL(cpu_emergency_register_virt_callback);
544
545void cpu_emergency_unregister_virt_callback(cpu_emergency_virt_cb *callback)
546{
547 if (WARN_ON_ONCE(rcu_access_pointer(cpu_emergency_virt_callback) != callback))
548 return;
549
550 rcu_assign_pointer(cpu_emergency_virt_callback, NULL);
551 synchronize_rcu();
552}
553EXPORT_SYMBOL_GPL(cpu_emergency_unregister_virt_callback);
554
555/*
556 * Disable virtualization, i.e. VMX or SVM, to ensure INIT is recognized during
557 * reboot. VMX blocks INIT if the CPU is post-VMXON, and SVM blocks INIT if
558 * GIF=0, i.e. if the crash occurred between CLGI and STGI.
559 */
560void cpu_emergency_disable_virtualization(void)
561{
562 cpu_emergency_virt_cb *callback;
563
564 /*
565 * IRQs must be disabled as KVM enables virtualization in hardware via
566 * function call IPIs, i.e. IRQs need to be disabled to guarantee
567 * virtualization stays disabled.
568 */
569 lockdep_assert_irqs_disabled();
570
571 rcu_read_lock();
572 callback = rcu_dereference(cpu_emergency_virt_callback);
573 if (callback)
574 callback();
575 rcu_read_unlock();
576}
577
578static void emergency_reboot_disable_virtualization(void)
579{
580 local_irq_disable();
581
582 /*
583 * Disable virtualization on all CPUs before rebooting to avoid hanging
584 * the system, as VMX and SVM block INIT when running in the host.
585 *
586 * We can't take any locks and we may be on an inconsistent state, so
587 * use NMIs as IPIs to tell the other CPUs to disable VMX/SVM and halt.
588 *
589 * Do the NMI shootdown even if virtualization is off on _this_ CPU, as
590 * other CPUs may have virtualization enabled.
591 */
592 if (rcu_access_pointer(cpu_emergency_virt_callback)) {
593 /* Safely force _this_ CPU out of VMX/SVM operation. */
594 cpu_emergency_disable_virtualization();
595
596 /* Disable VMX/SVM and halt on other CPUs. */
597 nmi_shootdown_cpus_on_restart();
598 }
599}
600#else
601static void emergency_reboot_disable_virtualization(void) { }
602#endif /* CONFIG_KVM_INTEL || CONFIG_KVM_AMD */
603
604void __attribute__((weak)) mach_reboot_fixups(void)
605{
606}
607
608/*
609 * To the best of our knowledge Windows compatible x86 hardware expects
610 * the following on reboot:
611 *
612 * 1) If the FADT has the ACPI reboot register flag set, try it
613 * 2) If still alive, write to the keyboard controller
614 * 3) If still alive, write to the ACPI reboot register again
615 * 4) If still alive, write to the keyboard controller again
616 * 5) If still alive, call the EFI runtime service to reboot
617 * 6) If no EFI runtime service, call the BIOS to do a reboot
618 *
619 * We default to following the same pattern. We also have
620 * two other reboot methods: 'triple fault' and 'PCI', which
621 * can be triggered via the reboot= kernel boot option or
622 * via quirks.
623 *
624 * This means that this function can never return, it can misbehave
625 * by not rebooting properly and hanging.
626 */
627static void native_machine_emergency_restart(void)
628{
629 int i;
630 int attempt = 0;
631 int orig_reboot_type = reboot_type;
632 unsigned short mode;
633
634 if (reboot_emergency)
635 emergency_reboot_disable_virtualization();
636
637 tboot_shutdown(TB_SHUTDOWN_REBOOT);
638
639 /* Tell the BIOS if we want cold or warm reboot */
640 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
641 *((unsigned short *)__va(0x472)) = mode;
642
643 /*
644 * If an EFI capsule has been registered with the firmware then
645 * override the reboot= parameter.
646 */
647 if (efi_capsule_pending(NULL)) {
648 pr_info("EFI capsule is pending, forcing EFI reboot.\n");
649 reboot_type = BOOT_EFI;
650 }
651
652 for (;;) {
653 /* Could also try the reset bit in the Hammer NB */
654 switch (reboot_type) {
655 case BOOT_ACPI:
656 acpi_reboot();
657 reboot_type = BOOT_KBD;
658 break;
659
660 case BOOT_KBD:
661 mach_reboot_fixups(); /* For board specific fixups */
662
663 for (i = 0; i < 10; i++) {
664 kb_wait();
665 udelay(50);
666 outb(0xfe, 0x64); /* Pulse reset low */
667 udelay(50);
668 }
669 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
670 attempt = 1;
671 reboot_type = BOOT_ACPI;
672 } else {
673 reboot_type = BOOT_EFI;
674 }
675 break;
676
677 case BOOT_EFI:
678 efi_reboot(reboot_mode, NULL);
679 reboot_type = BOOT_BIOS;
680 break;
681
682 case BOOT_BIOS:
683 machine_real_restart(MRR_BIOS);
684
685 /* We're probably dead after this, but... */
686 reboot_type = BOOT_CF9_SAFE;
687 break;
688
689 case BOOT_CF9_FORCE:
690 port_cf9_safe = true;
691 fallthrough;
692
693 case BOOT_CF9_SAFE:
694 if (port_cf9_safe) {
695 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E;
696 u8 cf9 = inb(0xcf9) & ~reboot_code;
697 outb(cf9|2, 0xcf9); /* Request hard reset */
698 udelay(50);
699 /* Actually do the reset */
700 outb(cf9|reboot_code, 0xcf9);
701 udelay(50);
702 }
703 reboot_type = BOOT_TRIPLE;
704 break;
705
706 case BOOT_TRIPLE:
707 idt_invalidate();
708 __asm__ __volatile__("int3");
709
710 /* We're probably dead after this, but... */
711 reboot_type = BOOT_KBD;
712 break;
713 }
714 }
715}
716
717void native_machine_shutdown(void)
718{
719 /* Stop the cpus and apics */
720#ifdef CONFIG_X86_IO_APIC
721 /*
722 * Disabling IO APIC before local APIC is a workaround for
723 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
724 * Specification Update". In this situation, interrupts that target
725 * a Logical Processor whose Local APIC is either in the process of
726 * being hardware disabled or software disabled are neither delivered
727 * nor discarded. When this erratum occurs, the processor may hang.
728 *
729 * Even without the erratum, it still makes sense to quiet IO APIC
730 * before disabling Local APIC.
731 */
732 clear_IO_APIC();
733#endif
734
735#ifdef CONFIG_SMP
736 /*
737 * Stop all of the others. Also disable the local irq to
738 * not receive the per-cpu timer interrupt which may trigger
739 * scheduler's load balance.
740 */
741 local_irq_disable();
742 stop_other_cpus();
743#endif
744
745 lapic_shutdown();
746 restore_boot_irq_mode();
747
748#ifdef CONFIG_HPET_TIMER
749 hpet_disable();
750#endif
751
752#ifdef CONFIG_X86_64
753 x86_platform.iommu_shutdown();
754#endif
755}
756
757static void __machine_emergency_restart(int emergency)
758{
759 reboot_emergency = emergency;
760 machine_ops.emergency_restart();
761}
762
763static void native_machine_restart(char *__unused)
764{
765 pr_notice("machine restart\n");
766
767 if (!reboot_force)
768 machine_shutdown();
769 __machine_emergency_restart(0);
770}
771
772static void native_machine_halt(void)
773{
774 /* Stop other cpus and apics */
775 machine_shutdown();
776
777 tboot_shutdown(TB_SHUTDOWN_HALT);
778
779 stop_this_cpu(NULL);
780}
781
782static void native_machine_power_off(void)
783{
784 if (kernel_can_power_off()) {
785 if (!reboot_force)
786 machine_shutdown();
787 do_kernel_power_off();
788 }
789 /* A fallback in case there is no PM info available */
790 tboot_shutdown(TB_SHUTDOWN_HALT);
791}
792
793struct machine_ops machine_ops __ro_after_init = {
794 .power_off = native_machine_power_off,
795 .shutdown = native_machine_shutdown,
796 .emergency_restart = native_machine_emergency_restart,
797 .restart = native_machine_restart,
798 .halt = native_machine_halt,
799#ifdef CONFIG_KEXEC_CORE
800 .crash_shutdown = native_machine_crash_shutdown,
801#endif
802};
803
804void machine_power_off(void)
805{
806 machine_ops.power_off();
807}
808
809void machine_shutdown(void)
810{
811 machine_ops.shutdown();
812}
813
814void machine_emergency_restart(void)
815{
816 __machine_emergency_restart(1);
817}
818
819void machine_restart(char *cmd)
820{
821 machine_ops.restart(cmd);
822}
823
824void machine_halt(void)
825{
826 machine_ops.halt();
827}
828
829#ifdef CONFIG_KEXEC_CORE
830void machine_crash_shutdown(struct pt_regs *regs)
831{
832 machine_ops.crash_shutdown(regs);
833}
834#endif
835
836/* This is the CPU performing the emergency shutdown work. */
837int crashing_cpu = -1;
838
839#if defined(CONFIG_SMP)
840
841static nmi_shootdown_cb shootdown_callback;
842
843static atomic_t waiting_for_crash_ipi;
844static int crash_ipi_issued;
845
846static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
847{
848 int cpu;
849
850 cpu = raw_smp_processor_id();
851
852 /*
853 * Don't do anything if this handler is invoked on crashing cpu.
854 * Otherwise, system will completely hang. Crashing cpu can get
855 * an NMI if system was initially booted with nmi_watchdog parameter.
856 */
857 if (cpu == crashing_cpu)
858 return NMI_HANDLED;
859 local_irq_disable();
860
861 if (shootdown_callback)
862 shootdown_callback(cpu, regs);
863
864 /*
865 * Prepare the CPU for reboot _after_ invoking the callback so that the
866 * callback can safely use virtualization instructions, e.g. VMCLEAR.
867 */
868 cpu_emergency_disable_virtualization();
869
870 atomic_dec(&waiting_for_crash_ipi);
871 /* Assume hlt works */
872 halt();
873 for (;;)
874 cpu_relax();
875
876 return NMI_HANDLED;
877}
878
879/**
880 * nmi_shootdown_cpus - Stop other CPUs via NMI
881 * @callback: Optional callback to be invoked from the NMI handler
882 *
883 * The NMI handler on the remote CPUs invokes @callback, if not
884 * NULL, first and then disables virtualization to ensure that
885 * INIT is recognized during reboot.
886 *
887 * nmi_shootdown_cpus() can only be invoked once. After the first
888 * invocation all other CPUs are stuck in crash_nmi_callback() and
889 * cannot respond to a second NMI.
890 */
891void nmi_shootdown_cpus(nmi_shootdown_cb callback)
892{
893 unsigned long msecs;
894
895 local_irq_disable();
896
897 /*
898 * Avoid certain doom if a shootdown already occurred; re-registering
899 * the NMI handler will cause list corruption, modifying the callback
900 * will do who knows what, etc...
901 */
902 if (WARN_ON_ONCE(crash_ipi_issued))
903 return;
904
905 /* Make a note of crashing cpu. Will be used in NMI callback. */
906 crashing_cpu = safe_smp_processor_id();
907
908 shootdown_callback = callback;
909
910 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
911 /* Would it be better to replace the trap vector here? */
912 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
913 NMI_FLAG_FIRST, "crash"))
914 return; /* Return what? */
915 /*
916 * Ensure the new callback function is set before sending
917 * out the NMI
918 */
919 wmb();
920
921 apic_send_IPI_allbutself(NMI_VECTOR);
922
923 /* Kick CPUs looping in NMI context. */
924 WRITE_ONCE(crash_ipi_issued, 1);
925
926 msecs = 1000; /* Wait at most a second for the other cpus to stop */
927 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
928 mdelay(1);
929 msecs--;
930 }
931
932 /*
933 * Leave the nmi callback set, shootdown is a one-time thing. Clearing
934 * the callback could result in a NULL pointer dereference if a CPU
935 * (finally) responds after the timeout expires.
936 */
937}
938
939static inline void nmi_shootdown_cpus_on_restart(void)
940{
941 if (!crash_ipi_issued)
942 nmi_shootdown_cpus(NULL);
943}
944
945/*
946 * Check if the crash dumping IPI got issued and if so, call its callback
947 * directly. This function is used when we have already been in NMI handler.
948 * It doesn't return.
949 */
950void run_crash_ipi_callback(struct pt_regs *regs)
951{
952 if (crash_ipi_issued)
953 crash_nmi_callback(0, regs);
954}
955
956/* Override the weak function in kernel/panic.c */
957void __noreturn nmi_panic_self_stop(struct pt_regs *regs)
958{
959 while (1) {
960 /* If no CPU is preparing crash dump, we simply loop here. */
961 run_crash_ipi_callback(regs);
962 cpu_relax();
963 }
964}
965
966#else /* !CONFIG_SMP */
967void nmi_shootdown_cpus(nmi_shootdown_cb callback)
968{
969 /* No other CPUs to shoot down */
970}
971
972static inline void nmi_shootdown_cpus_on_restart(void) { }
973
974void run_crash_ipi_callback(struct pt_regs *regs)
975{
976}
977#endif