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v5.4
  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
 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 MacBookPro5 */
201		.callback = set_pci_reboot,
202		.ident = "Apple MacBookPro5",
203		.matches = {
204			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
205			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
206		},
207	},
208	{	/* Handle problems with rebooting on Apple Macmini3,1 */
209		.callback = set_pci_reboot,
210		.ident = "Apple Macmini3,1",
211		.matches = {
212			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
213			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
214		},
215	},
216	{	/* Handle problems with rebooting on the iMac9,1. */
217		.callback = set_pci_reboot,
218		.ident = "Apple iMac9,1",
219		.matches = {
220			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
221			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
222		},
223	},
224	{	/* Handle problems with rebooting on the iMac10,1. */
225		.callback = set_pci_reboot,
226		.ident = "Apple iMac10,1",
227		.matches = {
228		    DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
229		    DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
230		},
231	},
232
233	/* ASRock */
234	{	/* Handle problems with rebooting on ASRock Q1900DC-ITX */
235		.callback = set_pci_reboot,
236		.ident = "ASRock Q1900DC-ITX",
237		.matches = {
238			DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
239			DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
240		},
241	},
242
243	/* ASUS */
244	{	/* Handle problems with rebooting on ASUS P4S800 */
245		.callback = set_bios_reboot,
246		.ident = "ASUS P4S800",
247		.matches = {
248			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
249			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
250		},
251	},
252	{	/* Handle problems with rebooting on ASUS EeeBook X205TA */
253		.callback = set_acpi_reboot,
254		.ident = "ASUS EeeBook X205TA",
255		.matches = {
256			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
257			DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"),
258		},
259	},
260	{	/* Handle problems with rebooting on ASUS EeeBook X205TAW */
261		.callback = set_acpi_reboot,
262		.ident = "ASUS EeeBook X205TAW",
263		.matches = {
264			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
265			DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"),
266		},
267	},
268
269	/* Certec */
270	{       /* Handle problems with rebooting on Certec BPC600 */
271		.callback = set_pci_reboot,
272		.ident = "Certec BPC600",
273		.matches = {
274			DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
275			DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
276		},
277	},
278
279	/* Dell */
280	{	/* Handle problems with rebooting on Dell DXP061 */
281		.callback = set_bios_reboot,
282		.ident = "Dell DXP061",
283		.matches = {
284			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
285			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
286		},
287	},
288	{	/* Handle problems with rebooting on Dell E520's */
289		.callback = set_bios_reboot,
290		.ident = "Dell E520",
291		.matches = {
292			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
293			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
294		},
295	},
296	{	/* Handle problems with rebooting on the Latitude E5410. */
297		.callback = set_pci_reboot,
298		.ident = "Dell Latitude E5410",
299		.matches = {
300			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
301			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
302		},
303	},
304	{	/* Handle problems with rebooting on the Latitude E5420. */
305		.callback = set_pci_reboot,
306		.ident = "Dell Latitude E5420",
307		.matches = {
308			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
309			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
310		},
311	},
312	{	/* Handle problems with rebooting on the Latitude E6320. */
313		.callback = set_pci_reboot,
314		.ident = "Dell Latitude E6320",
315		.matches = {
316			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
317			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
318		},
319	},
320	{	/* Handle problems with rebooting on the Latitude E6420. */
321		.callback = set_pci_reboot,
322		.ident = "Dell Latitude E6420",
323		.matches = {
324			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
325			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
326		},
327	},
328	{	/* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
329		.callback = set_bios_reboot,
330		.ident = "Dell OptiPlex 330",
331		.matches = {
332			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
333			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
334			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
335		},
336	},
337	{	/* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
338		.callback = set_bios_reboot,
339		.ident = "Dell OptiPlex 360",
340		.matches = {
341			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
342			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
343			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
344		},
345	},
346	{	/* Handle problems with rebooting on Dell Optiplex 745's SFF */
347		.callback = set_bios_reboot,
348		.ident = "Dell OptiPlex 745",
349		.matches = {
350			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
351			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
352		},
353	},
354	{	/* Handle problems with rebooting on Dell Optiplex 745's DFF */
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			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
361		},
362	},
363	{	/* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
364		.callback = set_bios_reboot,
365		.ident = "Dell OptiPlex 745",
366		.matches = {
367			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
368			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
369			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
370		},
371	},
372	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
373		.callback = set_bios_reboot,
374		.ident = "Dell OptiPlex 760",
375		.matches = {
376			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
377			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
378			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
379		},
380	},
381	{	/* Handle problems with rebooting on the OptiPlex 990. */
382		.callback = set_pci_reboot,
383		.ident = "Dell OptiPlex 990",
384		.matches = {
385			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
386			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
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	/* Sony */
473	{	/* Handle problems with rebooting on Sony VGN-Z540N */
474		.callback = set_bios_reboot,
475		.ident = "Sony VGN-Z540N",
476		.matches = {
477			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
478			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
479		},
480	},
481
482	{ }
483};
484
485static int __init reboot_init(void)
486{
487	int rv;
488
489	/*
490	 * Only do the DMI check if reboot_type hasn't been overridden
491	 * on the command line
492	 */
493	if (!reboot_default)
494		return 0;
495
496	/*
497	 * The DMI quirks table takes precedence. If no quirks entry
498	 * matches and the ACPI Hardware Reduced bit is set and EFI
499	 * runtime services are enabled, force EFI reboot.
500	 */
501	rv = dmi_check_system(reboot_dmi_table);
502
503	if (!rv && efi_reboot_required() && !efi_runtime_disabled())
504		reboot_type = BOOT_EFI;
505
506	return 0;
507}
508core_initcall(reboot_init);
509
510static inline void kb_wait(void)
511{
512	int i;
513
514	for (i = 0; i < 0x10000; i++) {
515		if ((inb(0x64) & 0x02) == 0)
516			break;
517		udelay(2);
518	}
519}
520
521static void vmxoff_nmi(int cpu, struct pt_regs *regs)
522{
523	cpu_emergency_vmxoff();
524}
525
526/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
527static void emergency_vmx_disable_all(void)
528{
529	/* Just make sure we won't change CPUs while doing this */
530	local_irq_disable();
531
532	/*
533	 * We need to disable VMX on all CPUs before rebooting, otherwise
534	 * we risk hanging up the machine, because the CPU ignore INIT
535	 * signals when VMX is enabled.
536	 *
537	 * We can't take any locks and we may be on an inconsistent
538	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
539	 * VMX and halt.
540	 *
541	 * For safety, we will avoid running the nmi_shootdown_cpus()
542	 * stuff unnecessarily, but we don't have a way to check
543	 * if other CPUs have VMX enabled. So we will call it only if the
544	 * CPU we are running on has VMX enabled.
545	 *
546	 * We will miss cases where VMX is not enabled on all CPUs. This
547	 * shouldn't do much harm because KVM always enable VMX on all
548	 * CPUs anyway. But we can miss it on the small window where KVM
549	 * is still enabling VMX.
550	 */
551	if (cpu_has_vmx() && cpu_vmx_enabled()) {
552		/* Disable VMX on this CPU. */
553		cpu_vmxoff();
554
555		/* Halt and disable VMX on the other CPUs */
556		nmi_shootdown_cpus(vmxoff_nmi);
557
558	}
559}
560
561
562void __attribute__((weak)) mach_reboot_fixups(void)
563{
564}
565
566/*
567 * To the best of our knowledge Windows compatible x86 hardware expects
568 * the following on reboot:
569 *
570 * 1) If the FADT has the ACPI reboot register flag set, try it
571 * 2) If still alive, write to the keyboard controller
572 * 3) If still alive, write to the ACPI reboot register again
573 * 4) If still alive, write to the keyboard controller again
574 * 5) If still alive, call the EFI runtime service to reboot
575 * 6) If no EFI runtime service, call the BIOS to do a reboot
576 *
577 * We default to following the same pattern. We also have
578 * two other reboot methods: 'triple fault' and 'PCI', which
579 * can be triggered via the reboot= kernel boot option or
580 * via quirks.
581 *
582 * This means that this function can never return, it can misbehave
583 * by not rebooting properly and hanging.
584 */
585static void native_machine_emergency_restart(void)
586{
587	int i;
588	int attempt = 0;
589	int orig_reboot_type = reboot_type;
590	unsigned short mode;
591
592	if (reboot_emergency)
593		emergency_vmx_disable_all();
594
595	tboot_shutdown(TB_SHUTDOWN_REBOOT);
596
597	/* Tell the BIOS if we want cold or warm reboot */
598	mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
599	*((unsigned short *)__va(0x472)) = mode;
600
601	/*
602	 * If an EFI capsule has been registered with the firmware then
603	 * override the reboot= parameter.
604	 */
605	if (efi_capsule_pending(NULL)) {
606		pr_info("EFI capsule is pending, forcing EFI reboot.\n");
607		reboot_type = BOOT_EFI;
608	}
609
610	for (;;) {
611		/* Could also try the reset bit in the Hammer NB */
612		switch (reboot_type) {
613		case BOOT_ACPI:
614			acpi_reboot();
615			reboot_type = BOOT_KBD;
616			break;
617
618		case BOOT_KBD:
619			mach_reboot_fixups(); /* For board specific fixups */
620
621			for (i = 0; i < 10; i++) {
622				kb_wait();
623				udelay(50);
624				outb(0xfe, 0x64); /* Pulse reset low */
625				udelay(50);
626			}
627			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
628				attempt = 1;
629				reboot_type = BOOT_ACPI;
630			} else {
631				reboot_type = BOOT_EFI;
632			}
633			break;
634
635		case BOOT_EFI:
636			efi_reboot(reboot_mode, NULL);
637			reboot_type = BOOT_BIOS;
638			break;
639
640		case BOOT_BIOS:
641			machine_real_restart(MRR_BIOS);
642
643			/* We're probably dead after this, but... */
644			reboot_type = BOOT_CF9_SAFE;
645			break;
646
647		case BOOT_CF9_FORCE:
648			port_cf9_safe = true;
649			/* Fall through */
650
651		case BOOT_CF9_SAFE:
652			if (port_cf9_safe) {
653				u8 reboot_code = reboot_mode == REBOOT_WARM ?  0x06 : 0x0E;
654				u8 cf9 = inb(0xcf9) & ~reboot_code;
655				outb(cf9|2, 0xcf9); /* Request hard reset */
656				udelay(50);
657				/* Actually do the reset */
658				outb(cf9|reboot_code, 0xcf9);
659				udelay(50);
660			}
661			reboot_type = BOOT_TRIPLE;
662			break;
663
664		case BOOT_TRIPLE:
665			idt_invalidate(NULL);
666			__asm__ __volatile__("int3");
667
668			/* We're probably dead after this, but... */
669			reboot_type = BOOT_KBD;
670			break;
671		}
672	}
673}
674
675void native_machine_shutdown(void)
676{
677	/* Stop the cpus and apics */
678#ifdef CONFIG_X86_IO_APIC
679	/*
680	 * Disabling IO APIC before local APIC is a workaround for
681	 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
682	 * Specification Update". In this situation, interrupts that target
683	 * a Logical Processor whose Local APIC is either in the process of
684	 * being hardware disabled or software disabled are neither delivered
685	 * nor discarded. When this erratum occurs, the processor may hang.
686	 *
687	 * Even without the erratum, it still makes sense to quiet IO APIC
688	 * before disabling Local APIC.
689	 */
690	clear_IO_APIC();
691#endif
692
693#ifdef CONFIG_SMP
694	/*
695	 * Stop all of the others. Also disable the local irq to
696	 * not receive the per-cpu timer interrupt which may trigger
697	 * scheduler's load balance.
698	 */
699	local_irq_disable();
700	stop_other_cpus();
701#endif
702
703	lapic_shutdown();
704	restore_boot_irq_mode();
705
706#ifdef CONFIG_HPET_TIMER
707	hpet_disable();
708#endif
709
710#ifdef CONFIG_X86_64
711	x86_platform.iommu_shutdown();
712#endif
713}
714
715static void __machine_emergency_restart(int emergency)
716{
717	reboot_emergency = emergency;
718	machine_ops.emergency_restart();
719}
720
721static void native_machine_restart(char *__unused)
722{
723	pr_notice("machine restart\n");
724
725	if (!reboot_force)
726		machine_shutdown();
727	__machine_emergency_restart(0);
728}
729
730static void native_machine_halt(void)
731{
732	/* Stop other cpus and apics */
733	machine_shutdown();
734
735	tboot_shutdown(TB_SHUTDOWN_HALT);
736
737	stop_this_cpu(NULL);
738}
739
740static void native_machine_power_off(void)
741{
742	if (pm_power_off) {
743		if (!reboot_force)
744			machine_shutdown();
745		pm_power_off();
746	}
747	/* A fallback in case there is no PM info available */
748	tboot_shutdown(TB_SHUTDOWN_HALT);
749}
750
751struct machine_ops machine_ops __ro_after_init = {
752	.power_off = native_machine_power_off,
753	.shutdown = native_machine_shutdown,
754	.emergency_restart = native_machine_emergency_restart,
755	.restart = native_machine_restart,
756	.halt = native_machine_halt,
757#ifdef CONFIG_KEXEC_CORE
758	.crash_shutdown = native_machine_crash_shutdown,
759#endif
760};
761
762void machine_power_off(void)
763{
764	machine_ops.power_off();
765}
766
767void machine_shutdown(void)
768{
769	machine_ops.shutdown();
770}
771
772void machine_emergency_restart(void)
773{
774	__machine_emergency_restart(1);
775}
776
777void machine_restart(char *cmd)
778{
779	machine_ops.restart(cmd);
780}
781
782void machine_halt(void)
783{
784	machine_ops.halt();
785}
786
787#ifdef CONFIG_KEXEC_CORE
788void machine_crash_shutdown(struct pt_regs *regs)
789{
790	machine_ops.crash_shutdown(regs);
791}
792#endif
793
794
795/* This is the CPU performing the emergency shutdown work. */
796int crashing_cpu = -1;
797
798#if defined(CONFIG_SMP)
799
800static nmi_shootdown_cb shootdown_callback;
801
802static atomic_t waiting_for_crash_ipi;
803static int crash_ipi_issued;
804
805static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
806{
807	int cpu;
808
809	cpu = raw_smp_processor_id();
810
811	/*
812	 * Don't do anything if this handler is invoked on crashing cpu.
813	 * Otherwise, system will completely hang. Crashing cpu can get
814	 * an NMI if system was initially booted with nmi_watchdog parameter.
815	 */
816	if (cpu == crashing_cpu)
817		return NMI_HANDLED;
818	local_irq_disable();
819
820	shootdown_callback(cpu, regs);
821
822	atomic_dec(&waiting_for_crash_ipi);
823	/* Assume hlt works */
824	halt();
825	for (;;)
826		cpu_relax();
827
828	return NMI_HANDLED;
829}
830
831/*
832 * Halt all other CPUs, calling the specified function on each of them
833 *
834 * This function can be used to halt all other CPUs on crash
835 * or emergency reboot time. The function passed as parameter
836 * will be called inside a NMI handler on all CPUs.
837 */
838void nmi_shootdown_cpus(nmi_shootdown_cb callback)
839{
840	unsigned long msecs;
841	local_irq_disable();
842
843	/* Make a note of crashing cpu. Will be used in NMI callback. */
844	crashing_cpu = safe_smp_processor_id();
845
846	shootdown_callback = callback;
847
848	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
849	/* Would it be better to replace the trap vector here? */
850	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
851				 NMI_FLAG_FIRST, "crash"))
852		return;		/* Return what? */
853	/*
854	 * Ensure the new callback function is set before sending
855	 * out the NMI
856	 */
857	wmb();
858
859	apic_send_IPI_allbutself(NMI_VECTOR);
860
861	/* Kick CPUs looping in NMI context. */
862	WRITE_ONCE(crash_ipi_issued, 1);
863
864	msecs = 1000; /* Wait at most a second for the other cpus to stop */
865	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
866		mdelay(1);
867		msecs--;
868	}
869
870	/* Leave the nmi callback set */
871}
872
873/*
874 * Check if the crash dumping IPI got issued and if so, call its callback
875 * directly. This function is used when we have already been in NMI handler.
876 * It doesn't return.
877 */
878void run_crash_ipi_callback(struct pt_regs *regs)
879{
880	if (crash_ipi_issued)
881		crash_nmi_callback(0, regs);
882}
883
884/* Override the weak function in kernel/panic.c */
885void nmi_panic_self_stop(struct pt_regs *regs)
886{
887	while (1) {
888		/* If no CPU is preparing crash dump, we simply loop here. */
889		run_crash_ipi_callback(regs);
890		cpu_relax();
891	}
892}
893
894#else /* !CONFIG_SMP */
895void nmi_shootdown_cpus(nmi_shootdown_cb callback)
896{
897	/* No other CPUs to shoot down */
898}
899
900void run_crash_ipi_callback(struct pt_regs *regs)
901{
902}
903#endif
v5.9
  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