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v3.5.6
  1#include <linux/module.h>
  2#include <linux/reboot.h>
  3#include <linux/init.h>
  4#include <linux/pm.h>
  5#include <linux/efi.h>
  6#include <linux/dmi.h>
  7#include <linux/sched.h>
  8#include <linux/tboot.h>
  9#include <linux/delay.h>
 10#include <acpi/reboot.h>
 11#include <asm/io.h>
 12#include <asm/apic.h>
 13#include <asm/desc.h>
 14#include <asm/hpet.h>
 15#include <asm/pgtable.h>
 16#include <asm/proto.h>
 17#include <asm/reboot_fixups.h>
 18#include <asm/reboot.h>
 19#include <asm/pci_x86.h>
 20#include <asm/virtext.h>
 21#include <asm/cpu.h>
 22#include <asm/nmi.h>
 23
 24#ifdef CONFIG_X86_32
 25# include <linux/ctype.h>
 26# include <linux/mc146818rtc.h>
 27# include <asm/realmode.h>
 28#else
 29# include <asm/x86_init.h>
 30#endif
 31
 32/*
 33 * Power off function, if any
 34 */
 35void (*pm_power_off)(void);
 36EXPORT_SYMBOL(pm_power_off);
 37
 38static const struct desc_ptr no_idt = {};
 39static int reboot_mode;
 40enum reboot_type reboot_type = BOOT_ACPI;
 41int reboot_force;
 42
 43/*
 44 * This variable is used privately to keep track of whether or not
 45 * reboot_type is still set to its default value (i.e., reboot= hasn't
 46 * been set on the command line).  This is needed so that we can
 47 * suppress DMI scanning for reboot quirks.  Without it, it's
 48 * impossible to override a faulty reboot quirk without recompiling.
 49 */
 50static int reboot_default = 1;
 51
 52#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
 53static int reboot_cpu = -1;
 54#endif
 55
 56/*
 57 * This is set if we need to go through the 'emergency' path.
 58 * When machine_emergency_restart() is called, we may be on
 59 * an inconsistent state and won't be able to do a clean cleanup
 60 */
 61static int reboot_emergency;
 62
 63/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 64bool port_cf9_safe = false;
 65
 66/*
 67 * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
 68 * warm   Don't set the cold reboot flag
 69 * cold   Set the cold reboot flag
 70 * bios   Reboot by jumping through the BIOS (only for X86_32)
 71 * smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
 72 * triple Force a triple fault (init)
 73 * kbd    Use the keyboard controller. cold reset (default)
 74 * acpi   Use the RESET_REG in the FADT
 75 * efi    Use efi reset_system runtime service
 76 * pci    Use the so-called "PCI reset register", CF9
 77 * force  Avoid anything that could hang.
 78 */
 79static int __init reboot_setup(char *str)
 80{
 81	for (;;) {
 82		/*
 83		 * Having anything passed on the command line via
 84		 * reboot= will cause us to disable DMI checking
 85		 * below.
 86		 */
 87		reboot_default = 0;
 88
 89		switch (*str) {
 90		case 'w':
 91			reboot_mode = 0x1234;
 92			break;
 93
 94		case 'c':
 95			reboot_mode = 0;
 96			break;
 97
 98#ifdef CONFIG_X86_32
 99#ifdef CONFIG_SMP
100		case 's':
101			if (isdigit(*(str+1))) {
102				reboot_cpu = (int) (*(str+1) - '0');
103				if (isdigit(*(str+2)))
104					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
105			}
106			/*
107			 * We will leave sorting out the final value
108			 * when we are ready to reboot, since we might not
109			 * have detected BSP APIC ID or smp_num_cpu
110			 */
111			break;
112#endif /* CONFIG_SMP */
113
114		case 'b':
115#endif
116		case 'a':
117		case 'k':
118		case 't':
119		case 'e':
120		case 'p':
121			reboot_type = *str;
122			break;
123
124		case 'f':
125			reboot_force = 1;
126			break;
127		}
128
129		str = strchr(str, ',');
130		if (str)
131			str++;
132		else
133			break;
134	}
135	return 1;
136}
137
138__setup("reboot=", reboot_setup);
139
140
141#ifdef CONFIG_X86_32
142/*
143 * Reboot options and system auto-detection code provided by
144 * Dell Inc. so their systems "just work". :-)
145 */
146
147/*
148 * Some machines require the "reboot=b" or "reboot=k"  commandline options,
149 * this quirk makes that automatic.
150 */
151static int __init set_bios_reboot(const struct dmi_system_id *d)
152{
153	if (reboot_type != BOOT_BIOS) {
154		reboot_type = BOOT_BIOS;
155		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
156	}
157	return 0;
158}
159
160void machine_real_restart(unsigned int type)
161{
162	void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
163		real_mode_header->machine_real_restart_asm;
164
165	local_irq_disable();
166
167	/*
168	 * Write zero to CMOS register number 0x0f, which the BIOS POST
169	 * routine will recognize as telling it to do a proper reboot.  (Well
170	 * that's what this book in front of me says -- it may only apply to
171	 * the Phoenix BIOS though, it's not clear).  At the same time,
172	 * disable NMIs by setting the top bit in the CMOS address register,
173	 * as we're about to do peculiar things to the CPU.  I'm not sure if
174	 * `outb_p' is needed instead of just `outb'.  Use it to be on the
175	 * safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
176	 */
177	spin_lock(&rtc_lock);
178	CMOS_WRITE(0x00, 0x8f);
179	spin_unlock(&rtc_lock);
180
181	/*
182	 * Switch back to the initial page table.
183	 */
184	load_cr3(initial_page_table);
185
186	/*
187	 * Write 0x1234 to absolute memory location 0x472.  The BIOS reads
188	 * this on booting to tell it to "Bypass memory test (also warm
189	 * boot)".  This seems like a fairly standard thing that gets set by
190	 * REBOOT.COM programs, and the previous reset routine did this
191	 * too. */
192	*((unsigned short *)0x472) = reboot_mode;
193
194	/* Jump to the identity-mapped low memory code */
195	restart_lowmem(type);
196}
197#ifdef CONFIG_APM_MODULE
198EXPORT_SYMBOL(machine_real_restart);
199#endif
200
201#endif /* CONFIG_X86_32 */
202
203/*
204 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
205 */
206static int __init set_pci_reboot(const struct dmi_system_id *d)
207{
208	if (reboot_type != BOOT_CF9) {
209		reboot_type = BOOT_CF9;
210		printk(KERN_INFO "%s series board detected. "
211		       "Selecting PCI-method for reboots.\n", d->ident);
212	}
213	return 0;
214}
215
216static int __init set_kbd_reboot(const struct dmi_system_id *d)
217{
218	if (reboot_type != BOOT_KBD) {
219		reboot_type = BOOT_KBD;
220		printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
221	}
222	return 0;
223}
224
225/*
226 * This is a single dmi_table handling all reboot quirks.  Note that
227 * REBOOT_BIOS is only available for 32bit
228 */
229static struct dmi_system_id __initdata reboot_dmi_table[] = {
230#ifdef CONFIG_X86_32
231	{	/* Handle problems with rebooting on Dell E520's */
232		.callback = set_bios_reboot,
233		.ident = "Dell E520",
234		.matches = {
235			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
236			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
237		},
238	},
239	{	/* Handle problems with rebooting on Dell 1300's */
240		.callback = set_bios_reboot,
241		.ident = "Dell PowerEdge 1300",
242		.matches = {
243			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
244			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
245		},
246	},
247	{	/* Handle problems with rebooting on Dell 300's */
248		.callback = set_bios_reboot,
249		.ident = "Dell PowerEdge 300",
250		.matches = {
251			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
252			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
253		},
254	},
255	{	/* Handle problems with rebooting on Dell Optiplex 745's SFF */
256		.callback = set_bios_reboot,
257		.ident = "Dell OptiPlex 745",
258		.matches = {
259			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
260			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
261		},
262	},
263	{	/* Handle problems with rebooting on Dell Optiplex 745's DFF */
264		.callback = set_bios_reboot,
265		.ident = "Dell OptiPlex 745",
266		.matches = {
267			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
268			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
269			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
270		},
271	},
272	{	/* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
273		.callback = set_bios_reboot,
274		.ident = "Dell OptiPlex 745",
275		.matches = {
276			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
277			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
278			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
279		},
280	},
281	{	/* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
282		.callback = set_bios_reboot,
283		.ident = "Dell OptiPlex 330",
284		.matches = {
285			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
286			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
287			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
288		},
289	},
290	{	/* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
291		.callback = set_bios_reboot,
292		.ident = "Dell OptiPlex 360",
293		.matches = {
294			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
295			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
296			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
297		},
298	},
299	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
300		.callback = set_bios_reboot,
301		.ident = "Dell OptiPlex 760",
302		.matches = {
303			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
304			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
305			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
306		},
307	},
308	{	/* Handle problems with rebooting on Dell 2400's */
309		.callback = set_bios_reboot,
310		.ident = "Dell PowerEdge 2400",
311		.matches = {
312			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
313			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
314		},
315	},
316	{	/* Handle problems with rebooting on Dell T5400's */
317		.callback = set_bios_reboot,
318		.ident = "Dell Precision T5400",
319		.matches = {
320			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
321			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
322		},
323	},
324	{	/* Handle problems with rebooting on Dell T7400's */
325		.callback = set_bios_reboot,
326		.ident = "Dell Precision T7400",
327		.matches = {
328			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
329			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
330		},
331	},
332	{	/* Handle problems with rebooting on HP laptops */
333		.callback = set_bios_reboot,
334		.ident = "HP Compaq Laptop",
335		.matches = {
336			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
337			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
338		},
339	},
340	{	/* Handle problems with rebooting on Dell XPS710 */
341		.callback = set_bios_reboot,
342		.ident = "Dell XPS710",
343		.matches = {
344			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
345			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
346		},
347	},
348	{	/* Handle problems with rebooting on Dell DXP061 */
349		.callback = set_bios_reboot,
350		.ident = "Dell DXP061",
351		.matches = {
352			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
353			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
354		},
355	},
356	{	/* Handle problems with rebooting on Sony VGN-Z540N */
357		.callback = set_bios_reboot,
358		.ident = "Sony VGN-Z540N",
359		.matches = {
360			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
361			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
362		},
363	},
364	{	/* Handle problems with rebooting on CompuLab SBC-FITPC2 */
365		.callback = set_bios_reboot,
366		.ident = "CompuLab SBC-FITPC2",
367		.matches = {
368			DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
369			DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
370		},
371	},
372	{	/* Handle problems with rebooting on ASUS P4S800 */
373		.callback = set_bios_reboot,
374		.ident = "ASUS P4S800",
375		.matches = {
376			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
377			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
378		},
379	},
380#endif /* CONFIG_X86_32 */
381
382	{	/* Handle reboot issue on Acer Aspire one */
383		.callback = set_kbd_reboot,
 
 
 
 
 
 
384		.ident = "Acer Aspire One A110",
385		.matches = {
386			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
387			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
388		},
389	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
390	{	/* Handle problems with rebooting on Apple MacBook5 */
391		.callback = set_pci_reboot,
392		.ident = "Apple MacBook5",
393		.matches = {
394			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
395			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
396		},
397	},
398	{	/* Handle problems with rebooting on Apple MacBookPro5 */
399		.callback = set_pci_reboot,
400		.ident = "Apple MacBookPro5",
401		.matches = {
402			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
403			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
404		},
405	},
406	{	/* Handle problems with rebooting on Apple Macmini3,1 */
407		.callback = set_pci_reboot,
408		.ident = "Apple Macmini3,1",
409		.matches = {
410			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
411			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
412		},
413	},
414	{	/* Handle problems with rebooting on the iMac9,1. */
415		.callback = set_pci_reboot,
416		.ident = "Apple iMac9,1",
417		.matches = {
418			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
419			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
420		},
421	},
422	{	/* Handle problems with rebooting on the Latitude E6320. */
423		.callback = set_pci_reboot,
424		.ident = "Dell Latitude E6320",
425		.matches = {
426			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
427			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
428		},
429	},
430	{	/* Handle problems with rebooting on the Latitude E5420. */
431		.callback = set_pci_reboot,
432		.ident = "Dell Latitude E5420",
433		.matches = {
434			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
435			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
436		},
437	},
438	{	/* Handle problems with rebooting on the Latitude E6420. */
439		.callback = set_pci_reboot,
440		.ident = "Dell Latitude E6420",
441		.matches = {
442			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
443			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
444		},
445	},
446	{	/* Handle problems with rebooting on the OptiPlex 990. */
447		.callback = set_pci_reboot,
448		.ident = "Dell OptiPlex 990",
449		.matches = {
450			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
451			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
452		},
453	},
454	{	/* Handle problems with rebooting on the Precision M6600. */
455		.callback = set_pci_reboot,
456		.ident = "Dell OptiPlex 990",
457		.matches = {
458			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
459			DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
460		},
461	},
462	{ }
463};
464
465static int __init reboot_init(void)
466{
467	/*
468	 * Only do the DMI check if reboot_type hasn't been overridden
469	 * on the command line
470	 */
471	if (reboot_default)
472		dmi_check_system(reboot_dmi_table);
473	return 0;
474}
475core_initcall(reboot_init);
476
477static inline void kb_wait(void)
478{
479	int i;
480
481	for (i = 0; i < 0x10000; i++) {
482		if ((inb(0x64) & 0x02) == 0)
483			break;
484		udelay(2);
485	}
486}
487
488static void vmxoff_nmi(int cpu, struct pt_regs *regs)
489{
490	cpu_emergency_vmxoff();
491}
492
493/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
 
494static void emergency_vmx_disable_all(void)
495{
496	/* Just make sure we won't change CPUs while doing this */
497	local_irq_disable();
498
499	/*
500	 * We need to disable VMX on all CPUs before rebooting, otherwise
501	 * we risk hanging up the machine, because the CPU ignore INIT
502	 * signals when VMX is enabled.
503	 *
504	 * We can't take any locks and we may be on an inconsistent
505	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
506	 * VMX and halt.
507	 *
508	 * For safety, we will avoid running the nmi_shootdown_cpus()
509	 * stuff unnecessarily, but we don't have a way to check
510	 * if other CPUs have VMX enabled. So we will call it only if the
511	 * CPU we are running on has VMX enabled.
512	 *
513	 * We will miss cases where VMX is not enabled on all CPUs. This
514	 * shouldn't do much harm because KVM always enable VMX on all
515	 * CPUs anyway. But we can miss it on the small window where KVM
516	 * is still enabling VMX.
517	 */
518	if (cpu_has_vmx() && cpu_vmx_enabled()) {
519		/* Disable VMX on this CPU. */
 
520		cpu_vmxoff();
521
522		/* Halt and disable VMX on the other CPUs */
523		nmi_shootdown_cpus(vmxoff_nmi);
524
525	}
526}
527
528
529void __attribute__((weak)) mach_reboot_fixups(void)
530{
531}
532
533/*
534 * Windows compatible x86 hardware expects the following on reboot:
535 *
536 * 1) If the FADT has the ACPI reboot register flag set, try it
537 * 2) If still alive, write to the keyboard controller
538 * 3) If still alive, write to the ACPI reboot register again
539 * 4) If still alive, write to the keyboard controller again
540 *
541 * If the machine is still alive at this stage, it gives up. We default to
542 * following the same pattern, except that if we're still alive after (4) we'll
543 * try to force a triple fault and then cycle between hitting the keyboard
544 * controller and doing that
545 */
546static void native_machine_emergency_restart(void)
547{
548	int i;
549	int attempt = 0;
550	int orig_reboot_type = reboot_type;
551
552	if (reboot_emergency)
553		emergency_vmx_disable_all();
554
555	tboot_shutdown(TB_SHUTDOWN_REBOOT);
556
557	/* Tell the BIOS if we want cold or warm reboot */
558	*((unsigned short *)__va(0x472)) = reboot_mode;
559
560	for (;;) {
561		/* Could also try the reset bit in the Hammer NB */
562		switch (reboot_type) {
563		case BOOT_KBD:
564			mach_reboot_fixups(); /* For board specific fixups */
565
566			for (i = 0; i < 10; i++) {
567				kb_wait();
568				udelay(50);
569				outb(0xfe, 0x64); /* Pulse reset low */
570				udelay(50);
571			}
572			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
573				attempt = 1;
574				reboot_type = BOOT_ACPI;
575			} else {
576				reboot_type = BOOT_TRIPLE;
577			}
578			break;
579
580		case BOOT_TRIPLE:
581			load_idt(&no_idt);
582			__asm__ __volatile__("int3");
583
584			reboot_type = BOOT_KBD;
585			break;
586
587#ifdef CONFIG_X86_32
588		case BOOT_BIOS:
589			machine_real_restart(MRR_BIOS);
590
591			reboot_type = BOOT_KBD;
592			break;
593#endif
594
595		case BOOT_ACPI:
596			acpi_reboot();
597			reboot_type = BOOT_KBD;
598			break;
599
600		case BOOT_EFI:
601			if (efi_enabled)
602				efi.reset_system(reboot_mode ?
603						 EFI_RESET_WARM :
604						 EFI_RESET_COLD,
605						 EFI_SUCCESS, 0, NULL);
606			reboot_type = BOOT_KBD;
607			break;
608
609		case BOOT_CF9:
610			port_cf9_safe = true;
611			/* Fall through */
612
613		case BOOT_CF9_COND:
614			if (port_cf9_safe) {
615				u8 cf9 = inb(0xcf9) & ~6;
616				outb(cf9|2, 0xcf9); /* Request hard reset */
617				udelay(50);
618				outb(cf9|6, 0xcf9); /* Actually do the reset */
619				udelay(50);
620			}
621			reboot_type = BOOT_KBD;
622			break;
623		}
624	}
625}
626
627void native_machine_shutdown(void)
628{
629	/* Stop the cpus and apics */
630#ifdef CONFIG_SMP
631
632	/* The boot cpu is always logical cpu 0 */
633	int reboot_cpu_id = 0;
634
635#ifdef CONFIG_X86_32
636	/* See if there has been given a command line override */
637	if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
638		cpu_online(reboot_cpu))
639		reboot_cpu_id = reboot_cpu;
640#endif
641
642	/* Make certain the cpu I'm about to reboot on is online */
643	if (!cpu_online(reboot_cpu_id))
644		reboot_cpu_id = smp_processor_id();
645
646	/* Make certain I only run on the appropriate processor */
647	set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
648
649	/*
650	 * O.K Now that I'm on the appropriate processor, stop all of the
651	 * others. Also disable the local irq to not receive the per-cpu
652	 * timer interrupt which may trigger scheduler's load balance.
653	 */
654	local_irq_disable();
655	stop_other_cpus();
656#endif
657
658	lapic_shutdown();
659
660#ifdef CONFIG_X86_IO_APIC
661	disable_IO_APIC();
662#endif
663
664#ifdef CONFIG_HPET_TIMER
665	hpet_disable();
666#endif
667
668#ifdef CONFIG_X86_64
669	x86_platform.iommu_shutdown();
670#endif
671}
672
673static void __machine_emergency_restart(int emergency)
674{
675	reboot_emergency = emergency;
676	machine_ops.emergency_restart();
677}
678
679static void native_machine_restart(char *__unused)
680{
681	printk("machine restart\n");
682
683	if (!reboot_force)
684		machine_shutdown();
685	__machine_emergency_restart(0);
686}
687
688static void native_machine_halt(void)
689{
690	/* Stop other cpus and apics */
691	machine_shutdown();
692
693	tboot_shutdown(TB_SHUTDOWN_HALT);
694
 
695	stop_this_cpu(NULL);
696}
697
698static void native_machine_power_off(void)
699{
700	if (pm_power_off) {
701		if (!reboot_force)
702			machine_shutdown();
703		pm_power_off();
704	}
705	/* A fallback in case there is no PM info available */
706	tboot_shutdown(TB_SHUTDOWN_HALT);
707}
708
709struct machine_ops machine_ops = {
710	.power_off = native_machine_power_off,
711	.shutdown = native_machine_shutdown,
712	.emergency_restart = native_machine_emergency_restart,
713	.restart = native_machine_restart,
714	.halt = native_machine_halt,
715#ifdef CONFIG_KEXEC
716	.crash_shutdown = native_machine_crash_shutdown,
717#endif
718};
719
720void machine_power_off(void)
721{
722	machine_ops.power_off();
723}
724
725void machine_shutdown(void)
726{
727	machine_ops.shutdown();
728}
729
730void machine_emergency_restart(void)
731{
732	__machine_emergency_restart(1);
733}
734
735void machine_restart(char *cmd)
736{
737	machine_ops.restart(cmd);
738}
739
740void machine_halt(void)
741{
742	machine_ops.halt();
743}
744
745#ifdef CONFIG_KEXEC
746void machine_crash_shutdown(struct pt_regs *regs)
747{
748	machine_ops.crash_shutdown(regs);
749}
750#endif
751
752
753#if defined(CONFIG_SMP)
754
755/* This keeps a track of which one is crashing cpu. */
756static int crashing_cpu;
757static nmi_shootdown_cb shootdown_callback;
758
759static atomic_t waiting_for_crash_ipi;
760
761static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
 
762{
763	int cpu;
764
 
 
 
765	cpu = raw_smp_processor_id();
766
767	/*
768	 * Don't do anything if this handler is invoked on crashing cpu.
769	 * Otherwise, system will completely hang. Crashing cpu can get
770	 * an NMI if system was initially booted with nmi_watchdog parameter.
771	 */
772	if (cpu == crashing_cpu)
773		return NMI_HANDLED;
774	local_irq_disable();
775
776	shootdown_callback(cpu, regs);
777
778	atomic_dec(&waiting_for_crash_ipi);
779	/* Assume hlt works */
780	halt();
781	for (;;)
782		cpu_relax();
783
784	return NMI_HANDLED;
785}
786
787static void smp_send_nmi_allbutself(void)
788{
789	apic->send_IPI_allbutself(NMI_VECTOR);
790}
791
792/*
793 * Halt all other CPUs, calling the specified function on each of them
 
 
 
 
 
794 *
795 * This function can be used to halt all other CPUs on crash
796 * or emergency reboot time. The function passed as parameter
797 * will be called inside a NMI handler on all CPUs.
798 */
799void nmi_shootdown_cpus(nmi_shootdown_cb callback)
800{
801	unsigned long msecs;
802	local_irq_disable();
803
804	/* Make a note of crashing cpu. Will be used in NMI callback. */
805	crashing_cpu = safe_smp_processor_id();
806
807	shootdown_callback = callback;
808
809	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
810	/* Would it be better to replace the trap vector here? */
811	if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
812				 NMI_FLAG_FIRST, "crash"))
813		return;		/* Return what? */
814	/*
815	 * Ensure the new callback function is set before sending
816	 * out the NMI
817	 */
818	wmb();
819
820	smp_send_nmi_allbutself();
821
822	msecs = 1000; /* Wait at most a second for the other cpus to stop */
823	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
824		mdelay(1);
825		msecs--;
826	}
827
828	/* Leave the nmi callback set */
829}
830#else /* !CONFIG_SMP */
831void nmi_shootdown_cpus(nmi_shootdown_cb callback)
832{
833	/* No other CPUs to shoot down */
834}
835#endif
v3.1
  1#include <linux/module.h>
  2#include <linux/reboot.h>
  3#include <linux/init.h>
  4#include <linux/pm.h>
  5#include <linux/efi.h>
  6#include <linux/dmi.h>
  7#include <linux/sched.h>
  8#include <linux/tboot.h>
  9#include <linux/delay.h>
 10#include <acpi/reboot.h>
 11#include <asm/io.h>
 12#include <asm/apic.h>
 13#include <asm/desc.h>
 14#include <asm/hpet.h>
 15#include <asm/pgtable.h>
 16#include <asm/proto.h>
 17#include <asm/reboot_fixups.h>
 18#include <asm/reboot.h>
 19#include <asm/pci_x86.h>
 20#include <asm/virtext.h>
 21#include <asm/cpu.h>
 22#include <asm/nmi.h>
 23
 24#ifdef CONFIG_X86_32
 25# include <linux/ctype.h>
 26# include <linux/mc146818rtc.h>
 
 27#else
 28# include <asm/x86_init.h>
 29#endif
 30
 31/*
 32 * Power off function, if any
 33 */
 34void (*pm_power_off)(void);
 35EXPORT_SYMBOL(pm_power_off);
 36
 37static const struct desc_ptr no_idt = {};
 38static int reboot_mode;
 39enum reboot_type reboot_type = BOOT_ACPI;
 40int reboot_force;
 41
 
 
 
 
 
 
 
 
 
 42#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
 43static int reboot_cpu = -1;
 44#endif
 45
 46/* This is set if we need to go through the 'emergency' path.
 
 47 * When machine_emergency_restart() is called, we may be on
 48 * an inconsistent state and won't be able to do a clean cleanup
 49 */
 50static int reboot_emergency;
 51
 52/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
 53bool port_cf9_safe = false;
 54
 55/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
 56   warm   Don't set the cold reboot flag
 57   cold   Set the cold reboot flag
 58   bios   Reboot by jumping through the BIOS (only for X86_32)
 59   smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
 60   triple Force a triple fault (init)
 61   kbd    Use the keyboard controller. cold reset (default)
 62   acpi   Use the RESET_REG in the FADT
 63   efi    Use efi reset_system runtime service
 64   pci    Use the so-called "PCI reset register", CF9
 65   force  Avoid anything that could hang.
 
 66 */
 67static int __init reboot_setup(char *str)
 68{
 69	for (;;) {
 
 
 
 
 
 
 
 70		switch (*str) {
 71		case 'w':
 72			reboot_mode = 0x1234;
 73			break;
 74
 75		case 'c':
 76			reboot_mode = 0;
 77			break;
 78
 79#ifdef CONFIG_X86_32
 80#ifdef CONFIG_SMP
 81		case 's':
 82			if (isdigit(*(str+1))) {
 83				reboot_cpu = (int) (*(str+1) - '0');
 84				if (isdigit(*(str+2)))
 85					reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
 86			}
 87				/* we will leave sorting out the final value
 88				   when we are ready to reboot, since we might not
 89				   have detected BSP APIC ID or smp_num_cpu */
 
 
 90			break;
 91#endif /* CONFIG_SMP */
 92
 93		case 'b':
 94#endif
 95		case 'a':
 96		case 'k':
 97		case 't':
 98		case 'e':
 99		case 'p':
100			reboot_type = *str;
101			break;
102
103		case 'f':
104			reboot_force = 1;
105			break;
106		}
107
108		str = strchr(str, ',');
109		if (str)
110			str++;
111		else
112			break;
113	}
114	return 1;
115}
116
117__setup("reboot=", reboot_setup);
118
119
120#ifdef CONFIG_X86_32
121/*
122 * Reboot options and system auto-detection code provided by
123 * Dell Inc. so their systems "just work". :-)
124 */
125
126/*
127 * Some machines require the "reboot=b"  commandline option,
128 * this quirk makes that automatic.
129 */
130static int __init set_bios_reboot(const struct dmi_system_id *d)
131{
132	if (reboot_type != BOOT_BIOS) {
133		reboot_type = BOOT_BIOS;
134		printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
135	}
136	return 0;
137}
138
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
139static struct dmi_system_id __initdata reboot_dmi_table[] = {
 
140	{	/* Handle problems with rebooting on Dell E520's */
141		.callback = set_bios_reboot,
142		.ident = "Dell E520",
143		.matches = {
144			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
145			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
146		},
147	},
148	{	/* Handle problems with rebooting on Dell 1300's */
149		.callback = set_bios_reboot,
150		.ident = "Dell PowerEdge 1300",
151		.matches = {
152			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
153			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
154		},
155	},
156	{	/* Handle problems with rebooting on Dell 300's */
157		.callback = set_bios_reboot,
158		.ident = "Dell PowerEdge 300",
159		.matches = {
160			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
161			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
162		},
163	},
164	{       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
165		.callback = set_bios_reboot,
166		.ident = "Dell OptiPlex 745",
167		.matches = {
168			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
169			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
170		},
171	},
172	{       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
173		.callback = set_bios_reboot,
174		.ident = "Dell OptiPlex 745",
175		.matches = {
176			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
177			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
178			DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
179		},
180	},
181	{       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
182		.callback = set_bios_reboot,
183		.ident = "Dell OptiPlex 745",
184		.matches = {
185			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
186			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
187			DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
188		},
189	},
190	{   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
191		.callback = set_bios_reboot,
192		.ident = "Dell OptiPlex 330",
193		.matches = {
194			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
195			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
196			DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
197		},
198	},
199	{   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
200		.callback = set_bios_reboot,
201		.ident = "Dell OptiPlex 360",
202		.matches = {
203			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
204			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
205			DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
206		},
207	},
208	{	/* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
209		.callback = set_bios_reboot,
210		.ident = "Dell OptiPlex 760",
211		.matches = {
212			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
213			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
214			DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
215		},
216	},
217	{	/* Handle problems with rebooting on Dell 2400's */
218		.callback = set_bios_reboot,
219		.ident = "Dell PowerEdge 2400",
220		.matches = {
221			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
222			DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
223		},
224	},
225	{	/* Handle problems with rebooting on Dell T5400's */
226		.callback = set_bios_reboot,
227		.ident = "Dell Precision T5400",
228		.matches = {
229			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
230			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
231		},
232	},
233	{	/* Handle problems with rebooting on Dell T7400's */
234		.callback = set_bios_reboot,
235		.ident = "Dell Precision T7400",
236		.matches = {
237			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
238			DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
239		},
240	},
241	{	/* Handle problems with rebooting on HP laptops */
242		.callback = set_bios_reboot,
243		.ident = "HP Compaq Laptop",
244		.matches = {
245			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
246			DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
247		},
248	},
249	{	/* Handle problems with rebooting on Dell XPS710 */
250		.callback = set_bios_reboot,
251		.ident = "Dell XPS710",
252		.matches = {
253			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
254			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
255		},
256	},
257	{	/* Handle problems with rebooting on Dell DXP061 */
258		.callback = set_bios_reboot,
259		.ident = "Dell DXP061",
260		.matches = {
261			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
262			DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
263		},
264	},
265	{	/* Handle problems with rebooting on Sony VGN-Z540N */
266		.callback = set_bios_reboot,
267		.ident = "Sony VGN-Z540N",
268		.matches = {
269			DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
270			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
271		},
272	},
273	{	/* Handle problems with rebooting on CompuLab SBC-FITPC2 */
274		.callback = set_bios_reboot,
275		.ident = "CompuLab SBC-FITPC2",
276		.matches = {
277			DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
278			DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
279		},
280	},
281	{       /* Handle problems with rebooting on ASUS P4S800 */
282		.callback = set_bios_reboot,
283		.ident = "ASUS P4S800",
284		.matches = {
285			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
286			DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
287		},
288	},
289	{	/* Handle problems with rebooting on VersaLogic Menlow boards */
290		.callback = set_bios_reboot,
291		.ident = "VersaLogic Menlow based board",
292		.matches = {
293			DMI_MATCH(DMI_BOARD_VENDOR, "VersaLogic Corporation"),
294			DMI_MATCH(DMI_BOARD_NAME, "VersaLogic Menlow board"),
295		},
296	},
297	{ /* Handle reboot issue on Acer Aspire one */
298		.callback = set_bios_reboot,
299		.ident = "Acer Aspire One A110",
300		.matches = {
301			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
302			DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
303		},
304	},
305	{ }
306};
307
308static int __init reboot_init(void)
309{
310	dmi_check_system(reboot_dmi_table);
311	return 0;
312}
313core_initcall(reboot_init);
314
315extern const unsigned char machine_real_restart_asm[];
316extern const u64 machine_real_restart_gdt[3];
317
318void machine_real_restart(unsigned int type)
319{
320	void *restart_va;
321	unsigned long restart_pa;
322	void (*restart_lowmem)(unsigned int);
323	u64 *lowmem_gdt;
324
325	local_irq_disable();
326
327	/* Write zero to CMOS register number 0x0f, which the BIOS POST
328	   routine will recognize as telling it to do a proper reboot.  (Well
329	   that's what this book in front of me says -- it may only apply to
330	   the Phoenix BIOS though, it's not clear).  At the same time,
331	   disable NMIs by setting the top bit in the CMOS address register,
332	   as we're about to do peculiar things to the CPU.  I'm not sure if
333	   `outb_p' is needed instead of just `outb'.  Use it to be on the
334	   safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
335	 */
336	spin_lock(&rtc_lock);
337	CMOS_WRITE(0x00, 0x8f);
338	spin_unlock(&rtc_lock);
339
340	/*
341	 * Switch back to the initial page table.
342	 */
343	load_cr3(initial_page_table);
344
345	/* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
346	   this on booting to tell it to "Bypass memory test (also warm
347	   boot)".  This seems like a fairly standard thing that gets set by
348	   REBOOT.COM programs, and the previous reset routine did this
349	   too. */
350	*((unsigned short *)0x472) = reboot_mode;
351
352	/* Patch the GDT in the low memory trampoline */
353	lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
354
355	restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
356	restart_pa = virt_to_phys(restart_va);
357	restart_lowmem = (void (*)(unsigned int))restart_pa;
358
359	/* GDT[0]: GDT self-pointer */
360	lowmem_gdt[0] =
361		(u64)(sizeof(machine_real_restart_gdt) - 1) +
362		((u64)virt_to_phys(lowmem_gdt) << 16);
363	/* GDT[1]: 64K real mode code segment */
364	lowmem_gdt[1] =
365		GDT_ENTRY(0x009b, restart_pa, 0xffff);
366
367	/* Jump to the identity-mapped low memory code */
368	restart_lowmem(type);
369}
370#ifdef CONFIG_APM_MODULE
371EXPORT_SYMBOL(machine_real_restart);
372#endif
373
374#endif /* CONFIG_X86_32 */
375
376/*
377 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
378 */
379static int __init set_pci_reboot(const struct dmi_system_id *d)
380{
381	if (reboot_type != BOOT_CF9) {
382		reboot_type = BOOT_CF9;
383		printk(KERN_INFO "%s series board detected. "
384		       "Selecting PCI-method for reboots.\n", d->ident);
385	}
386	return 0;
387}
388
389static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
390	{	/* Handle problems with rebooting on Apple MacBook5 */
391		.callback = set_pci_reboot,
392		.ident = "Apple MacBook5",
393		.matches = {
394			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
395			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
396		},
397	},
398	{	/* Handle problems with rebooting on Apple MacBookPro5 */
399		.callback = set_pci_reboot,
400		.ident = "Apple MacBookPro5",
401		.matches = {
402			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
403			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
404		},
405	},
406	{	/* Handle problems with rebooting on Apple Macmini3,1 */
407		.callback = set_pci_reboot,
408		.ident = "Apple Macmini3,1",
409		.matches = {
410			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
411			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
412		},
413	},
414	{	/* Handle problems with rebooting on the iMac9,1. */
415		.callback = set_pci_reboot,
416		.ident = "Apple iMac9,1",
417		.matches = {
418			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
419			DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
420		},
421	},
422	{	/* Handle problems with rebooting on the Latitude E6320. */
423		.callback = set_pci_reboot,
424		.ident = "Dell Latitude E6320",
425		.matches = {
426			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
427			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
428		},
429	},
430	{	/* Handle problems with rebooting on the Latitude E5420. */
431		.callback = set_pci_reboot,
432		.ident = "Dell Latitude E5420",
433		.matches = {
434			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
435			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
436		},
437	},
438	{	/* Handle problems with rebooting on the Latitude E6420. */
439		.callback = set_pci_reboot,
440		.ident = "Dell Latitude E6420",
441		.matches = {
442			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
443			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
444		},
445	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
446	{ }
447};
448
449static int __init pci_reboot_init(void)
450{
451	dmi_check_system(pci_reboot_dmi_table);
 
 
 
 
 
452	return 0;
453}
454core_initcall(pci_reboot_init);
455
456static inline void kb_wait(void)
457{
458	int i;
459
460	for (i = 0; i < 0x10000; i++) {
461		if ((inb(0x64) & 0x02) == 0)
462			break;
463		udelay(2);
464	}
465}
466
467static void vmxoff_nmi(int cpu, struct die_args *args)
468{
469	cpu_emergency_vmxoff();
470}
471
472/* Use NMIs as IPIs to tell all CPUs to disable virtualization
473 */
474static void emergency_vmx_disable_all(void)
475{
476	/* Just make sure we won't change CPUs while doing this */
477	local_irq_disable();
478
479	/* We need to disable VMX on all CPUs before rebooting, otherwise
 
480	 * we risk hanging up the machine, because the CPU ignore INIT
481	 * signals when VMX is enabled.
482	 *
483	 * We can't take any locks and we may be on an inconsistent
484	 * state, so we use NMIs as IPIs to tell the other CPUs to disable
485	 * VMX and halt.
486	 *
487	 * For safety, we will avoid running the nmi_shootdown_cpus()
488	 * stuff unnecessarily, but we don't have a way to check
489	 * if other CPUs have VMX enabled. So we will call it only if the
490	 * CPU we are running on has VMX enabled.
491	 *
492	 * We will miss cases where VMX is not enabled on all CPUs. This
493	 * shouldn't do much harm because KVM always enable VMX on all
494	 * CPUs anyway. But we can miss it on the small window where KVM
495	 * is still enabling VMX.
496	 */
497	if (cpu_has_vmx() && cpu_vmx_enabled()) {
498		/* Disable VMX on this CPU.
499		 */
500		cpu_vmxoff();
501
502		/* Halt and disable VMX on the other CPUs */
503		nmi_shootdown_cpus(vmxoff_nmi);
504
505	}
506}
507
508
509void __attribute__((weak)) mach_reboot_fixups(void)
510{
511}
512
513/*
514 * Windows compatible x86 hardware expects the following on reboot:
515 *
516 * 1) If the FADT has the ACPI reboot register flag set, try it
517 * 2) If still alive, write to the keyboard controller
518 * 3) If still alive, write to the ACPI reboot register again
519 * 4) If still alive, write to the keyboard controller again
520 *
521 * If the machine is still alive at this stage, it gives up. We default to
522 * following the same pattern, except that if we're still alive after (4) we'll
523 * try to force a triple fault and then cycle between hitting the keyboard
524 * controller and doing that
525 */
526static void native_machine_emergency_restart(void)
527{
528	int i;
529	int attempt = 0;
530	int orig_reboot_type = reboot_type;
531
532	if (reboot_emergency)
533		emergency_vmx_disable_all();
534
535	tboot_shutdown(TB_SHUTDOWN_REBOOT);
536
537	/* Tell the BIOS if we want cold or warm reboot */
538	*((unsigned short *)__va(0x472)) = reboot_mode;
539
540	for (;;) {
541		/* Could also try the reset bit in the Hammer NB */
542		switch (reboot_type) {
543		case BOOT_KBD:
544			mach_reboot_fixups(); /* for board specific fixups */
545
546			for (i = 0; i < 10; i++) {
547				kb_wait();
548				udelay(50);
549				outb(0xfe, 0x64); /* pulse reset low */
550				udelay(50);
551			}
552			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
553				attempt = 1;
554				reboot_type = BOOT_ACPI;
555			} else {
556				reboot_type = BOOT_TRIPLE;
557			}
558			break;
559
560		case BOOT_TRIPLE:
561			load_idt(&no_idt);
562			__asm__ __volatile__("int3");
563
564			reboot_type = BOOT_KBD;
565			break;
566
567#ifdef CONFIG_X86_32
568		case BOOT_BIOS:
569			machine_real_restart(MRR_BIOS);
570
571			reboot_type = BOOT_KBD;
572			break;
573#endif
574
575		case BOOT_ACPI:
576			acpi_reboot();
577			reboot_type = BOOT_KBD;
578			break;
579
580		case BOOT_EFI:
581			if (efi_enabled)
582				efi.reset_system(reboot_mode ?
583						 EFI_RESET_WARM :
584						 EFI_RESET_COLD,
585						 EFI_SUCCESS, 0, NULL);
586			reboot_type = BOOT_KBD;
587			break;
588
589		case BOOT_CF9:
590			port_cf9_safe = true;
591			/* fall through */
592
593		case BOOT_CF9_COND:
594			if (port_cf9_safe) {
595				u8 cf9 = inb(0xcf9) & ~6;
596				outb(cf9|2, 0xcf9); /* Request hard reset */
597				udelay(50);
598				outb(cf9|6, 0xcf9); /* Actually do the reset */
599				udelay(50);
600			}
601			reboot_type = BOOT_KBD;
602			break;
603		}
604	}
605}
606
607void native_machine_shutdown(void)
608{
609	/* Stop the cpus and apics */
610#ifdef CONFIG_SMP
611
612	/* The boot cpu is always logical cpu 0 */
613	int reboot_cpu_id = 0;
614
615#ifdef CONFIG_X86_32
616	/* See if there has been given a command line override */
617	if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
618		cpu_online(reboot_cpu))
619		reboot_cpu_id = reboot_cpu;
620#endif
621
622	/* Make certain the cpu I'm about to reboot on is online */
623	if (!cpu_online(reboot_cpu_id))
624		reboot_cpu_id = smp_processor_id();
625
626	/* Make certain I only run on the appropriate processor */
627	set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
628
629	/* O.K Now that I'm on the appropriate processor,
630	 * stop all of the others.
 
 
631	 */
 
632	stop_other_cpus();
633#endif
634
635	lapic_shutdown();
636
637#ifdef CONFIG_X86_IO_APIC
638	disable_IO_APIC();
639#endif
640
641#ifdef CONFIG_HPET_TIMER
642	hpet_disable();
643#endif
644
645#ifdef CONFIG_X86_64
646	x86_platform.iommu_shutdown();
647#endif
648}
649
650static void __machine_emergency_restart(int emergency)
651{
652	reboot_emergency = emergency;
653	machine_ops.emergency_restart();
654}
655
656static void native_machine_restart(char *__unused)
657{
658	printk("machine restart\n");
659
660	if (!reboot_force)
661		machine_shutdown();
662	__machine_emergency_restart(0);
663}
664
665static void native_machine_halt(void)
666{
667	/* stop other cpus and apics */
668	machine_shutdown();
669
670	tboot_shutdown(TB_SHUTDOWN_HALT);
671
672	/* stop this cpu */
673	stop_this_cpu(NULL);
674}
675
676static void native_machine_power_off(void)
677{
678	if (pm_power_off) {
679		if (!reboot_force)
680			machine_shutdown();
681		pm_power_off();
682	}
683	/* a fallback in case there is no PM info available */
684	tboot_shutdown(TB_SHUTDOWN_HALT);
685}
686
687struct machine_ops machine_ops = {
688	.power_off = native_machine_power_off,
689	.shutdown = native_machine_shutdown,
690	.emergency_restart = native_machine_emergency_restart,
691	.restart = native_machine_restart,
692	.halt = native_machine_halt,
693#ifdef CONFIG_KEXEC
694	.crash_shutdown = native_machine_crash_shutdown,
695#endif
696};
697
698void machine_power_off(void)
699{
700	machine_ops.power_off();
701}
702
703void machine_shutdown(void)
704{
705	machine_ops.shutdown();
706}
707
708void machine_emergency_restart(void)
709{
710	__machine_emergency_restart(1);
711}
712
713void machine_restart(char *cmd)
714{
715	machine_ops.restart(cmd);
716}
717
718void machine_halt(void)
719{
720	machine_ops.halt();
721}
722
723#ifdef CONFIG_KEXEC
724void machine_crash_shutdown(struct pt_regs *regs)
725{
726	machine_ops.crash_shutdown(regs);
727}
728#endif
729
730
731#if defined(CONFIG_SMP)
732
733/* This keeps a track of which one is crashing cpu. */
734static int crashing_cpu;
735static nmi_shootdown_cb shootdown_callback;
736
737static atomic_t waiting_for_crash_ipi;
738
739static int crash_nmi_callback(struct notifier_block *self,
740			unsigned long val, void *data)
741{
742	int cpu;
743
744	if (val != DIE_NMI)
745		return NOTIFY_OK;
746
747	cpu = raw_smp_processor_id();
748
749	/* Don't do anything if this handler is invoked on crashing cpu.
 
750	 * Otherwise, system will completely hang. Crashing cpu can get
751	 * an NMI if system was initially booted with nmi_watchdog parameter.
752	 */
753	if (cpu == crashing_cpu)
754		return NOTIFY_STOP;
755	local_irq_disable();
756
757	shootdown_callback(cpu, (struct die_args *)data);
758
759	atomic_dec(&waiting_for_crash_ipi);
760	/* Assume hlt works */
761	halt();
762	for (;;)
763		cpu_relax();
764
765	return 1;
766}
767
768static void smp_send_nmi_allbutself(void)
769{
770	apic->send_IPI_allbutself(NMI_VECTOR);
771}
772
773static struct notifier_block crash_nmi_nb = {
774	.notifier_call = crash_nmi_callback,
775	/* we want to be the first one called */
776	.priority = NMI_LOCAL_HIGH_PRIOR+1,
777};
778
779/* Halt all other CPUs, calling the specified function on each of them
780 *
781 * This function can be used to halt all other CPUs on crash
782 * or emergency reboot time. The function passed as parameter
783 * will be called inside a NMI handler on all CPUs.
784 */
785void nmi_shootdown_cpus(nmi_shootdown_cb callback)
786{
787	unsigned long msecs;
788	local_irq_disable();
789
790	/* Make a note of crashing cpu. Will be used in NMI callback.*/
791	crashing_cpu = safe_smp_processor_id();
792
793	shootdown_callback = callback;
794
795	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
796	/* Would it be better to replace the trap vector here? */
797	if (register_die_notifier(&crash_nmi_nb))
798		return;		/* return what? */
799	/* Ensure the new callback function is set before sending
 
 
800	 * out the NMI
801	 */
802	wmb();
803
804	smp_send_nmi_allbutself();
805
806	msecs = 1000; /* Wait at most a second for the other cpus to stop */
807	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
808		mdelay(1);
809		msecs--;
810	}
811
812	/* Leave the nmi callback set */
813}
814#else /* !CONFIG_SMP */
815void nmi_shootdown_cpus(nmi_shootdown_cb callback)
816{
817	/* No other CPUs to shoot down */
818}
819#endif