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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
v4.10.11
 
  1#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  2
  3#include <linux/export.h>
  4#include <linux/reboot.h>
  5#include <linux/init.h>
  6#include <linux/pm.h>
  7#include <linux/efi.h>
  8#include <linux/dmi.h>
  9#include <linux/sched.h>
 10#include <linux/tboot.h>
 11#include <linux/delay.h>
 
 
 12#include <acpi/reboot.h>
 13#include <asm/io.h>
 14#include <asm/apic.h>
 15#include <asm/io_apic.h>
 16#include <asm/desc.h>
 17#include <asm/hpet.h>
 18#include <asm/pgtable.h>
 19#include <asm/proto.h>
 20#include <asm/reboot_fixups.h>
 21#include <asm/reboot.h>
 22#include <asm/pci_x86.h>
 23#include <asm/virtext.h>
 24#include <asm/cpu.h>
 25#include <asm/nmi.h>
 26#include <asm/smp.h>
 27
 28#include <linux/ctype.h>
 29#include <linux/mc146818rtc.h>
 30#include <asm/realmode.h>
 31#include <asm/x86_init.h>
 32#include <asm/efi.h>
 33
 34/*
 35 * Power off function, if any
 36 */
 37void (*pm_power_off)(void);
 38EXPORT_SYMBOL(pm_power_off);
 39
 40static const struct desc_ptr no_idt = {};
 41
 42/*
 43 * This is set if we need to go through the 'emergency' path.
 44 * When machine_emergency_restart() is called, we may be on
 45 * an inconsistent state and won't be able to do a clean cleanup
 46 */
 47static int reboot_emergency;
 48
 49/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 50bool port_cf9_safe = false;
 51
 52/*
 53 * Reboot options and system auto-detection code provided by
 54 * Dell Inc. so their systems "just work". :-)
 55 */
 56
 57/*
 58 * Some machines require the "reboot=a" commandline options
 59 */
 60static int __init set_acpi_reboot(const struct dmi_system_id *d)
 61{
 62	if (reboot_type != BOOT_ACPI) {
 63		reboot_type = BOOT_ACPI;
 64		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
 65			d->ident, "ACPI");
 66	}
 67	return 0;
 68}
 69
 70/*
 71 * Some machines require the "reboot=b" or "reboot=k"  commandline options,
 72 * this quirk makes that automatic.
 73 */
 74static int __init set_bios_reboot(const struct dmi_system_id *d)
 75{
 76	if (reboot_type != BOOT_BIOS) {
 77		reboot_type = BOOT_BIOS;
 78		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
 79			d->ident, "BIOS");
 80	}
 81	return 0;
 82}
 83
 
 
 
 
 
 
 
 
 
 
 
 
 
 84void __noreturn machine_real_restart(unsigned int type)
 85{
 86	local_irq_disable();
 87
 88	/*
 89	 * Write zero to CMOS register number 0x0f, which the BIOS POST
 90	 * routine will recognize as telling it to do a proper reboot.  (Well
 91	 * that's what this book in front of me says -- it may only apply to
 92	 * the Phoenix BIOS though, it's not clear).  At the same time,
 93	 * disable NMIs by setting the top bit in the CMOS address register,
 94	 * as we're about to do peculiar things to the CPU.  I'm not sure if
 95	 * `outb_p' is needed instead of just `outb'.  Use it to be on the
 96	 * safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 97	 */
 98	spin_lock(&rtc_lock);
 99	CMOS_WRITE(0x00, 0x8f);
100	spin_unlock(&rtc_lock);
101
102	/*
103	 * Switch back to the initial page table.
104	 */
105#ifdef CONFIG_X86_32
106	load_cr3(initial_page_table);
107#else
108	write_cr3(real_mode_header->trampoline_pgd);
 
 
 
 
109#endif
110
111	/* Jump to the identity-mapped low memory code */
112#ifdef CONFIG_X86_32
113	asm volatile("jmpl *%0" : :
114		     "rm" (real_mode_header->machine_real_restart_asm),
115		     "a" (type));
116#else
117	asm volatile("ljmpl *%0" : :
118		     "m" (real_mode_header->machine_real_restart_asm),
119		     "D" (type));
120#endif
121	unreachable();
122}
123#ifdef CONFIG_APM_MODULE
124EXPORT_SYMBOL(machine_real_restart);
125#endif
 
126
127/*
128 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
129 */
130static int __init set_pci_reboot(const struct dmi_system_id *d)
131{
132	if (reboot_type != BOOT_CF9_FORCE) {
133		reboot_type = BOOT_CF9_FORCE;
134		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
135			d->ident, "PCI");
136	}
137	return 0;
138}
139
140static int __init set_kbd_reboot(const struct dmi_system_id *d)
141{
142	if (reboot_type != BOOT_KBD) {
143		reboot_type = BOOT_KBD;
144		pr_info("%s series board detected. Selecting %s-method for reboot.\n",
145			d->ident, "KBD");
146	}
147	return 0;
148}
149
150/*
151 * This is a single dmi_table handling all reboot quirks.
152 */
153static struct dmi_system_id __initdata reboot_dmi_table[] = {
154
155	/* Acer */
156	{	/* Handle reboot issue on Acer Aspire one */
157		.callback = set_kbd_reboot,
158		.ident = "Acer Aspire One A110",
159		.matches = {
160			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
161			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
162		},
163	},
 
 
 
 
 
 
 
 
164
165	/* Apple */
166	{	/* Handle problems with rebooting on Apple MacBook5 */
167		.callback = set_pci_reboot,
168		.ident = "Apple MacBook5",
169		.matches = {
170			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
171			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
172		},
173	},
 
 
 
 
 
 
 
 
174	{	/* Handle problems with rebooting on Apple MacBookPro5 */
175		.callback = set_pci_reboot,
176		.ident = "Apple MacBookPro5",
177		.matches = {
178			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
179			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
180		},
181	},
182	{	/* Handle problems with rebooting on Apple Macmini3,1 */
183		.callback = set_pci_reboot,
184		.ident = "Apple Macmini3,1",
185		.matches = {
186			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
187			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
188		},
189	},
190	{	/* Handle problems with rebooting on the iMac9,1. */
191		.callback = set_pci_reboot,
192		.ident = "Apple iMac9,1",
193		.matches = {
194			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
195			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
196		},
197	},
198	{	/* Handle problems with rebooting on the iMac10,1. */
199		.callback = set_pci_reboot,
200		.ident = "Apple iMac10,1",
201		.matches = {
202		    DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
203		    DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
204		},
205	},
206
207	/* ASRock */
208	{	/* Handle problems with rebooting on ASRock Q1900DC-ITX */
209		.callback = set_pci_reboot,
210		.ident = "ASRock Q1900DC-ITX",
211		.matches = {
212			DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
213			DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
214		},
215	},
216
217	/* ASUS */
218	{	/* Handle problems with rebooting on ASUS P4S800 */
219		.callback = set_bios_reboot,
220		.ident = "ASUS P4S800",
221		.matches = {
222			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
223			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
224		},
225	},
226	{	/* Handle problems with rebooting on ASUS EeeBook X205TA */
227		.callback = set_acpi_reboot,
228		.ident = "ASUS EeeBook X205TA",
229		.matches = {
230			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
231			DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"),
232		},
233	},
234	{	/* Handle problems with rebooting on ASUS EeeBook X205TAW */
235		.callback = set_acpi_reboot,
236		.ident = "ASUS EeeBook X205TAW",
237		.matches = {
238			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
239			DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"),
240		},
241	},
242
243	/* Certec */
244	{       /* Handle problems with rebooting on Certec BPC600 */
245		.callback = set_pci_reboot,
246		.ident = "Certec BPC600",
247		.matches = {
248			DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
249			DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
250		},
251	},
252
253	/* Dell */
254	{	/* Handle problems with rebooting on Dell DXP061 */
255		.callback = set_bios_reboot,
256		.ident = "Dell DXP061",
257		.matches = {
258			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
259			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
260		},
261	},
262	{	/* Handle problems with rebooting on Dell E520's */
263		.callback = set_bios_reboot,
264		.ident = "Dell E520",
265		.matches = {
266			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
267			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
268		},
269	},
270	{	/* Handle problems with rebooting on the Latitude E5410. */
271		.callback = set_pci_reboot,
272		.ident = "Dell Latitude E5410",
273		.matches = {
274			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
275			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
276		},
277	},
278	{	/* Handle problems with rebooting on the Latitude E5420. */
279		.callback = set_pci_reboot,
280		.ident = "Dell Latitude E5420",
281		.matches = {
282			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
283			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
284		},
285	},
286	{	/* Handle problems with rebooting on the Latitude E6320. */
287		.callback = set_pci_reboot,
288		.ident = "Dell Latitude E6320",
289		.matches = {
290			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
291			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
292		},
293	},
294	{	/* Handle problems with rebooting on the Latitude E6420. */
295		.callback = set_pci_reboot,
296		.ident = "Dell Latitude E6420",
297		.matches = {
298			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
299			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
300		},
301	},
302	{	/* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
303		.callback = set_bios_reboot,
304		.ident = "Dell OptiPlex 330",
305		.matches = {
306			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
307			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
308			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
309		},
310	},
311	{	/* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
312		.callback = set_bios_reboot,
313		.ident = "Dell OptiPlex 360",
314		.matches = {
315			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
316			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
317			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
318		},
319	},
320	{	/* Handle problems with rebooting on Dell Optiplex 745's SFF */
321		.callback = set_bios_reboot,
322		.ident = "Dell OptiPlex 745",
323		.matches = {
324			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
325			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
326		},
327	},
328	{	/* Handle problems with rebooting on Dell Optiplex 745's DFF */
329		.callback = set_bios_reboot,
330		.ident = "Dell OptiPlex 745",
331		.matches = {
332			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
333			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
334			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
335		},
336	},
337	{	/* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
338		.callback = set_bios_reboot,
339		.ident = "Dell OptiPlex 745",
340		.matches = {
341			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
342			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
343			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
344		},
345	},
346	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
347		.callback = set_bios_reboot,
348		.ident = "Dell OptiPlex 760",
349		.matches = {
350			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
351			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
352			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
353		},
354	},
355	{	/* Handle problems with rebooting on the OptiPlex 990. */
356		.callback = set_pci_reboot,
357		.ident = "Dell OptiPlex 990",
358		.matches = {
359			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
360			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
361		},
362	},
363	{	/* Handle problems with rebooting on Dell 300's */
364		.callback = set_bios_reboot,
365		.ident = "Dell PowerEdge 300",
366		.matches = {
367			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
368			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
369		},
370	},
371	{	/* Handle problems with rebooting on Dell 1300's */
372		.callback = set_bios_reboot,
373		.ident = "Dell PowerEdge 1300",
374		.matches = {
375			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
376			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
377		},
378	},
379	{	/* Handle problems with rebooting on Dell 2400's */
380		.callback = set_bios_reboot,
381		.ident = "Dell PowerEdge 2400",
382		.matches = {
383			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
384			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
385		},
386	},
387	{	/* Handle problems with rebooting on the Dell PowerEdge C6100. */
388		.callback = set_pci_reboot,
389		.ident = "Dell PowerEdge C6100",
390		.matches = {
391			DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
392			DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
393		},
394	},
395	{	/* Handle problems with rebooting on the Precision M6600. */
396		.callback = set_pci_reboot,
397		.ident = "Dell Precision M6600",
398		.matches = {
399			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
400			DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
401		},
402	},
403	{	/* Handle problems with rebooting on Dell T5400's */
404		.callback = set_bios_reboot,
405		.ident = "Dell Precision T5400",
406		.matches = {
407			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
408			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
409		},
410	},
411	{	/* Handle problems with rebooting on Dell T7400's */
412		.callback = set_bios_reboot,
413		.ident = "Dell Precision T7400",
414		.matches = {
415			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
416			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
417		},
418	},
419	{	/* Handle problems with rebooting on Dell XPS710 */
420		.callback = set_bios_reboot,
421		.ident = "Dell XPS710",
422		.matches = {
423			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
424			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
425		},
426	},
427	{	/* Handle problems with rebooting on Dell Optiplex 7450 AIO */
428		.callback = set_acpi_reboot,
429		.ident = "Dell OptiPlex 7450 AIO",
430		.matches = {
431			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
432			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"),
433		},
434	},
435
436	/* Hewlett-Packard */
437	{	/* Handle problems with rebooting on HP laptops */
438		.callback = set_bios_reboot,
439		.ident = "HP Compaq Laptop",
440		.matches = {
441			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
442			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
443		},
444	},
445
446	/* Sony */
447	{	/* Handle problems with rebooting on Sony VGN-Z540N */
448		.callback = set_bios_reboot,
449		.ident = "Sony VGN-Z540N",
450		.matches = {
451			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
452			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
453		},
454	},
455
456	{ }
457};
458
459static int __init reboot_init(void)
460{
461	int rv;
462
463	/*
464	 * Only do the DMI check if reboot_type hasn't been overridden
465	 * on the command line
466	 */
467	if (!reboot_default)
468		return 0;
469
470	/*
471	 * The DMI quirks table takes precedence. If no quirks entry
472	 * matches and the ACPI Hardware Reduced bit is set, force EFI
473	 * reboot.
474	 */
475	rv = dmi_check_system(reboot_dmi_table);
476
477	if (!rv && efi_reboot_required())
478		reboot_type = BOOT_EFI;
479
480	return 0;
481}
482core_initcall(reboot_init);
483
484static inline void kb_wait(void)
485{
486	int i;
487
488	for (i = 0; i < 0x10000; i++) {
489		if ((inb(0x64) & 0x02) == 0)
490			break;
491		udelay(2);
492	}
493}
494
495static void vmxoff_nmi(int cpu, struct pt_regs *regs)
496{
497	cpu_emergency_vmxoff();
498}
499
500/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
501static void emergency_vmx_disable_all(void)
502{
503	/* Just make sure we won't change CPUs while doing this */
504	local_irq_disable();
505
506	/*
507	 * We need to disable VMX on all CPUs before rebooting, otherwise
508	 * we risk hanging up the machine, because the CPU ignore INIT
509	 * signals when VMX is enabled.
510	 *
511	 * We can't take any locks and we may be on an inconsistent
512	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
513	 * VMX and halt.
514	 *
515	 * For safety, we will avoid running the nmi_shootdown_cpus()
516	 * stuff unnecessarily, but we don't have a way to check
517	 * if other CPUs have VMX enabled. So we will call it only if the
518	 * CPU we are running on has VMX enabled.
519	 *
520	 * We will miss cases where VMX is not enabled on all CPUs. This
521	 * shouldn't do much harm because KVM always enable VMX on all
522	 * CPUs anyway. But we can miss it on the small window where KVM
523	 * is still enabling VMX.
524	 */
525	if (cpu_has_vmx() && cpu_vmx_enabled()) {
526		/* Disable VMX on this CPU. */
527		cpu_vmxoff();
528
529		/* Halt and disable VMX on the other CPUs */
530		nmi_shootdown_cpus(vmxoff_nmi);
531
532	}
533}
534
535
536void __attribute__((weak)) mach_reboot_fixups(void)
537{
538}
539
540/*
541 * To the best of our knowledge Windows compatible x86 hardware expects
542 * the following on reboot:
543 *
544 * 1) If the FADT has the ACPI reboot register flag set, try it
545 * 2) If still alive, write to the keyboard controller
546 * 3) If still alive, write to the ACPI reboot register again
547 * 4) If still alive, write to the keyboard controller again
548 * 5) If still alive, call the EFI runtime service to reboot
549 * 6) If no EFI runtime service, call the BIOS to do a reboot
550 *
551 * We default to following the same pattern. We also have
552 * two other reboot methods: 'triple fault' and 'PCI', which
553 * can be triggered via the reboot= kernel boot option or
554 * via quirks.
555 *
556 * This means that this function can never return, it can misbehave
557 * by not rebooting properly and hanging.
558 */
559static void native_machine_emergency_restart(void)
560{
561	int i;
562	int attempt = 0;
563	int orig_reboot_type = reboot_type;
564	unsigned short mode;
565
566	if (reboot_emergency)
567		emergency_vmx_disable_all();
568
569	tboot_shutdown(TB_SHUTDOWN_REBOOT);
570
571	/* Tell the BIOS if we want cold or warm reboot */
572	mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
573	*((unsigned short *)__va(0x472)) = mode;
574
575	/*
576	 * If an EFI capsule has been registered with the firmware then
577	 * override the reboot= parameter.
578	 */
579	if (efi_capsule_pending(NULL)) {
580		pr_info("EFI capsule is pending, forcing EFI reboot.\n");
581		reboot_type = BOOT_EFI;
582	}
583
584	for (;;) {
585		/* Could also try the reset bit in the Hammer NB */
586		switch (reboot_type) {
587		case BOOT_ACPI:
588			acpi_reboot();
589			reboot_type = BOOT_KBD;
590			break;
591
592		case BOOT_KBD:
593			mach_reboot_fixups(); /* For board specific fixups */
594
595			for (i = 0; i < 10; i++) {
596				kb_wait();
597				udelay(50);
598				outb(0xfe, 0x64); /* Pulse reset low */
599				udelay(50);
600			}
601			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
602				attempt = 1;
603				reboot_type = BOOT_ACPI;
604			} else {
605				reboot_type = BOOT_EFI;
606			}
607			break;
608
609		case BOOT_EFI:
610			efi_reboot(reboot_mode, NULL);
611			reboot_type = BOOT_BIOS;
612			break;
613
614		case BOOT_BIOS:
615			machine_real_restart(MRR_BIOS);
616
617			/* We're probably dead after this, but... */
618			reboot_type = BOOT_CF9_SAFE;
619			break;
620
621		case BOOT_CF9_FORCE:
622			port_cf9_safe = true;
623			/* Fall through */
624
625		case BOOT_CF9_SAFE:
626			if (port_cf9_safe) {
627				u8 reboot_code = reboot_mode == REBOOT_WARM ?  0x06 : 0x0E;
628				u8 cf9 = inb(0xcf9) & ~reboot_code;
629				outb(cf9|2, 0xcf9); /* Request hard reset */
630				udelay(50);
631				/* Actually do the reset */
632				outb(cf9|reboot_code, 0xcf9);
633				udelay(50);
634			}
635			reboot_type = BOOT_TRIPLE;
636			break;
637
638		case BOOT_TRIPLE:
639			load_idt(&no_idt);
640			__asm__ __volatile__("int3");
641
642			/* We're probably dead after this, but... */
643			reboot_type = BOOT_KBD;
644			break;
645		}
646	}
647}
648
649void native_machine_shutdown(void)
650{
651	/* Stop the cpus and apics */
652#ifdef CONFIG_X86_IO_APIC
653	/*
654	 * Disabling IO APIC before local APIC is a workaround for
655	 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
656	 * Specification Update". In this situation, interrupts that target
657	 * a Logical Processor whose Local APIC is either in the process of
658	 * being hardware disabled or software disabled are neither delivered
659	 * nor discarded. When this erratum occurs, the processor may hang.
660	 *
661	 * Even without the erratum, it still makes sense to quiet IO APIC
662	 * before disabling Local APIC.
663	 */
664	disable_IO_APIC();
665#endif
666
667#ifdef CONFIG_SMP
668	/*
669	 * Stop all of the others. Also disable the local irq to
670	 * not receive the per-cpu timer interrupt which may trigger
671	 * scheduler's load balance.
672	 */
673	local_irq_disable();
674	stop_other_cpus();
675#endif
676
677	lapic_shutdown();
 
678
679#ifdef CONFIG_HPET_TIMER
680	hpet_disable();
681#endif
682
683#ifdef CONFIG_X86_64
684	x86_platform.iommu_shutdown();
685#endif
686}
687
688static void __machine_emergency_restart(int emergency)
689{
690	reboot_emergency = emergency;
691	machine_ops.emergency_restart();
692}
693
694static void native_machine_restart(char *__unused)
695{
696	pr_notice("machine restart\n");
697
698	if (!reboot_force)
699		machine_shutdown();
700	__machine_emergency_restart(0);
701}
702
703static void native_machine_halt(void)
704{
705	/* Stop other cpus and apics */
706	machine_shutdown();
707
708	tboot_shutdown(TB_SHUTDOWN_HALT);
709
710	stop_this_cpu(NULL);
711}
712
713static void native_machine_power_off(void)
714{
715	if (pm_power_off) {
716		if (!reboot_force)
717			machine_shutdown();
718		pm_power_off();
719	}
720	/* A fallback in case there is no PM info available */
721	tboot_shutdown(TB_SHUTDOWN_HALT);
722}
723
724struct machine_ops machine_ops __ro_after_init = {
725	.power_off = native_machine_power_off,
726	.shutdown = native_machine_shutdown,
727	.emergency_restart = native_machine_emergency_restart,
728	.restart = native_machine_restart,
729	.halt = native_machine_halt,
730#ifdef CONFIG_KEXEC_CORE
731	.crash_shutdown = native_machine_crash_shutdown,
732#endif
733};
734
735void machine_power_off(void)
736{
737	machine_ops.power_off();
738}
739
740void machine_shutdown(void)
741{
742	machine_ops.shutdown();
743}
744
745void machine_emergency_restart(void)
746{
747	__machine_emergency_restart(1);
748}
749
750void machine_restart(char *cmd)
751{
752	machine_ops.restart(cmd);
753}
754
755void machine_halt(void)
756{
757	machine_ops.halt();
758}
759
760#ifdef CONFIG_KEXEC_CORE
761void machine_crash_shutdown(struct pt_regs *regs)
762{
763	machine_ops.crash_shutdown(regs);
764}
765#endif
766
767
 
 
 
768#if defined(CONFIG_SMP)
769
770/* This keeps a track of which one is crashing cpu. */
771static int crashing_cpu;
772static nmi_shootdown_cb shootdown_callback;
773
774static atomic_t waiting_for_crash_ipi;
775static int crash_ipi_issued;
776
777static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
778{
779	int cpu;
780
781	cpu = raw_smp_processor_id();
782
783	/*
784	 * Don't do anything if this handler is invoked on crashing cpu.
785	 * Otherwise, system will completely hang. Crashing cpu can get
786	 * an NMI if system was initially booted with nmi_watchdog parameter.
787	 */
788	if (cpu == crashing_cpu)
789		return NMI_HANDLED;
790	local_irq_disable();
791
792	shootdown_callback(cpu, regs);
793
794	atomic_dec(&waiting_for_crash_ipi);
795	/* Assume hlt works */
796	halt();
797	for (;;)
798		cpu_relax();
799
800	return NMI_HANDLED;
801}
802
803static void smp_send_nmi_allbutself(void)
804{
805	apic->send_IPI_allbutself(NMI_VECTOR);
806}
807
808/*
809 * Halt all other CPUs, calling the specified function on each of them
810 *
811 * This function can be used to halt all other CPUs on crash
812 * or emergency reboot time. The function passed as parameter
813 * will be called inside a NMI handler on all CPUs.
814 */
815void nmi_shootdown_cpus(nmi_shootdown_cb callback)
816{
817	unsigned long msecs;
818	local_irq_disable();
819
820	/* Make a note of crashing cpu. Will be used in NMI callback. */
821	crashing_cpu = safe_smp_processor_id();
822
823	shootdown_callback = callback;
824
825	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
826	/* Would it be better to replace the trap vector here? */
827	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
828				 NMI_FLAG_FIRST, "crash"))
829		return;		/* Return what? */
830	/*
831	 * Ensure the new callback function is set before sending
832	 * out the NMI
833	 */
834	wmb();
835
836	smp_send_nmi_allbutself();
837
838	/* Kick CPUs looping in NMI context. */
839	WRITE_ONCE(crash_ipi_issued, 1);
840
841	msecs = 1000; /* Wait at most a second for the other cpus to stop */
842	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
843		mdelay(1);
844		msecs--;
845	}
846
847	/* Leave the nmi callback set */
848}
849
850/*
851 * Check if the crash dumping IPI got issued and if so, call its callback
852 * directly. This function is used when we have already been in NMI handler.
853 * It doesn't return.
854 */
855void run_crash_ipi_callback(struct pt_regs *regs)
856{
857	if (crash_ipi_issued)
858		crash_nmi_callback(0, regs);
859}
860
861/* Override the weak function in kernel/panic.c */
862void nmi_panic_self_stop(struct pt_regs *regs)
863{
864	while (1) {
865		/* If no CPU is preparing crash dump, we simply loop here. */
866		run_crash_ipi_callback(regs);
867		cpu_relax();
868	}
869}
870
871#else /* !CONFIG_SMP */
872void nmi_shootdown_cpus(nmi_shootdown_cb callback)
873{
874	/* No other CPUs to shoot down */
875}
876
877void run_crash_ipi_callback(struct pt_regs *regs)
878{
879}
880#endif