1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
3 #include <linux/module.h>
4 #include <linux/reboot.h>
5 #include <linux/init.h>
9 #include <linux/sched.h>
10 #include <linux/tboot.h>
11 #include <linux/delay.h>
12 #include <acpi/reboot.h>
15 #include <asm/io_apic.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>
28 #include <linux/ctype.h>
29 #include <linux/mc146818rtc.h>
30 #include <asm/realmode.h>
31 #include <asm/x86_init.h>
35 * Power off function, if any
37 void (*pm_power_off)(void);
38 EXPORT_SYMBOL(pm_power_off);
40 static const struct desc_ptr no_idt = {};
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
47 static int reboot_emergency;
49 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
50 bool port_cf9_safe = false;
53 * Reboot options and system auto-detection code provided by
54 * Dell Inc. so their systems "just work". :-)
58 * Some machines require the "reboot=b" or "reboot=k" commandline options,
59 * this quirk makes that automatic.
61 static int __init set_bios_reboot(const struct dmi_system_id *d)
63 if (reboot_type != BOOT_BIOS) {
64 reboot_type = BOOT_BIOS;
65 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
71 void __noreturn machine_real_restart(unsigned int type)
76 * Write zero to CMOS register number 0x0f, which the BIOS POST
77 * routine will recognize as telling it to do a proper reboot. (Well
78 * that's what this book in front of me says -- it may only apply to
79 * the Phoenix BIOS though, it's not clear). At the same time,
80 * disable NMIs by setting the top bit in the CMOS address register,
81 * as we're about to do peculiar things to the CPU. I'm not sure if
82 * `outb_p' is needed instead of just `outb'. Use it to be on the
83 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
86 CMOS_WRITE(0x00, 0x8f);
87 spin_unlock(&rtc_lock);
90 * Switch back to the initial page table.
93 load_cr3(initial_page_table);
95 write_cr3(real_mode_header->trampoline_pgd);
98 /* Jump to the identity-mapped low memory code */
100 asm volatile("jmpl *%0" : :
101 "rm" (real_mode_header->machine_real_restart_asm),
104 asm volatile("ljmpl *%0" : :
105 "m" (real_mode_header->machine_real_restart_asm),
110 #ifdef CONFIG_APM_MODULE
111 EXPORT_SYMBOL(machine_real_restart);
115 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
117 static int __init set_pci_reboot(const struct dmi_system_id *d)
119 if (reboot_type != BOOT_CF9_FORCE) {
120 reboot_type = BOOT_CF9_FORCE;
121 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
127 static int __init set_kbd_reboot(const struct dmi_system_id *d)
129 if (reboot_type != BOOT_KBD) {
130 reboot_type = BOOT_KBD;
131 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
138 * This is a single dmi_table handling all reboot quirks.
140 static struct dmi_system_id __initdata reboot_dmi_table[] = {
143 { /* Handle reboot issue on Acer Aspire one */
144 .callback = set_kbd_reboot,
145 .ident = "Acer Aspire One A110",
147 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
148 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
153 { /* Handle problems with rebooting on Apple MacBook5 */
154 .callback = set_pci_reboot,
155 .ident = "Apple MacBook5",
157 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
158 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
161 { /* Handle problems with rebooting on Apple MacBookPro5 */
162 .callback = set_pci_reboot,
163 .ident = "Apple MacBookPro5",
165 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
166 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
169 { /* Handle problems with rebooting on Apple Macmini3,1 */
170 .callback = set_pci_reboot,
171 .ident = "Apple Macmini3,1",
173 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
174 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
177 { /* Handle problems with rebooting on the iMac9,1. */
178 .callback = set_pci_reboot,
179 .ident = "Apple iMac9,1",
181 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
182 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
185 { /* Handle problems with rebooting on the iMac10,1. */
186 .callback = set_pci_reboot,
187 .ident = "Apple iMac10,1",
189 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
190 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"),
195 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
196 .callback = set_pci_reboot,
197 .ident = "ASRock Q1900DC-ITX",
199 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"),
200 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
205 { /* Handle problems with rebooting on ASUS P4S800 */
206 .callback = set_bios_reboot,
207 .ident = "ASUS P4S800",
209 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
210 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
215 { /* Handle problems with rebooting on Certec BPC600 */
216 .callback = set_pci_reboot,
217 .ident = "Certec BPC600",
219 DMI_MATCH(DMI_SYS_VENDOR, "Certec"),
220 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"),
225 { /* Handle problems with rebooting on Dell DXP061 */
226 .callback = set_bios_reboot,
227 .ident = "Dell DXP061",
229 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
230 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
233 { /* Handle problems with rebooting on Dell E520's */
234 .callback = set_bios_reboot,
235 .ident = "Dell E520",
237 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
238 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
241 { /* Handle problems with rebooting on the Latitude E5410. */
242 .callback = set_pci_reboot,
243 .ident = "Dell Latitude E5410",
245 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
246 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"),
249 { /* Handle problems with rebooting on the Latitude E5420. */
250 .callback = set_pci_reboot,
251 .ident = "Dell Latitude E5420",
253 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
254 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
257 { /* Handle problems with rebooting on the Latitude E6320. */
258 .callback = set_pci_reboot,
259 .ident = "Dell Latitude E6320",
261 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
262 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
265 { /* Handle problems with rebooting on the Latitude E6420. */
266 .callback = set_pci_reboot,
267 .ident = "Dell Latitude E6420",
269 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
270 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
273 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
274 .callback = set_bios_reboot,
275 .ident = "Dell OptiPlex 330",
277 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
278 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
279 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
282 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
283 .callback = set_bios_reboot,
284 .ident = "Dell OptiPlex 360",
286 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
287 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
288 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
291 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
292 .callback = set_bios_reboot,
293 .ident = "Dell OptiPlex 745",
295 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
296 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
299 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
300 .callback = set_bios_reboot,
301 .ident = "Dell OptiPlex 745",
303 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
304 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
305 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
308 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
309 .callback = set_bios_reboot,
310 .ident = "Dell OptiPlex 745",
312 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
313 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
314 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
317 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
318 .callback = set_bios_reboot,
319 .ident = "Dell OptiPlex 760",
321 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
322 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
323 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
326 { /* Handle problems with rebooting on the OptiPlex 990. */
327 .callback = set_pci_reboot,
328 .ident = "Dell OptiPlex 990",
330 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
331 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
334 { /* Handle problems with rebooting on Dell 300's */
335 .callback = set_bios_reboot,
336 .ident = "Dell PowerEdge 300",
338 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
339 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
342 { /* Handle problems with rebooting on Dell 1300's */
343 .callback = set_bios_reboot,
344 .ident = "Dell PowerEdge 1300",
346 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
347 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
350 { /* Handle problems with rebooting on Dell 2400's */
351 .callback = set_bios_reboot,
352 .ident = "Dell PowerEdge 2400",
354 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
355 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
358 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
359 .callback = set_pci_reboot,
360 .ident = "Dell PowerEdge C6100",
362 DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
363 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"),
366 { /* Handle problems with rebooting on the Precision M6600. */
367 .callback = set_pci_reboot,
368 .ident = "Dell Precision M6600",
370 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
371 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
374 { /* Handle problems with rebooting on Dell T5400's */
375 .callback = set_bios_reboot,
376 .ident = "Dell Precision T5400",
378 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
379 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
382 { /* Handle problems with rebooting on Dell T7400's */
383 .callback = set_bios_reboot,
384 .ident = "Dell Precision T7400",
386 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
387 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
390 { /* Handle problems with rebooting on Dell XPS710 */
391 .callback = set_bios_reboot,
392 .ident = "Dell XPS710",
394 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
395 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
399 /* Hewlett-Packard */
400 { /* Handle problems with rebooting on HP laptops */
401 .callback = set_bios_reboot,
402 .ident = "HP Compaq Laptop",
404 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
405 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
410 { /* Handle problems with rebooting on Sony VGN-Z540N */
411 .callback = set_bios_reboot,
412 .ident = "Sony VGN-Z540N",
414 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
415 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
422 static int __init reboot_init(void)
427 * Only do the DMI check if reboot_type hasn't been overridden
428 * on the command line
434 * The DMI quirks table takes precedence. If no quirks entry
435 * matches and the ACPI Hardware Reduced bit is set, force EFI
438 rv = dmi_check_system(reboot_dmi_table);
440 if (!rv && efi_reboot_required())
441 reboot_type = BOOT_EFI;
445 core_initcall(reboot_init);
447 static inline void kb_wait(void)
451 for (i = 0; i < 0x10000; i++) {
452 if ((inb(0x64) & 0x02) == 0)
458 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
460 cpu_emergency_vmxoff();
463 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
464 static void emergency_vmx_disable_all(void)
466 /* Just make sure we won't change CPUs while doing this */
470 * We need to disable VMX on all CPUs before rebooting, otherwise
471 * we risk hanging up the machine, because the CPU ignore INIT
472 * signals when VMX is enabled.
474 * We can't take any locks and we may be on an inconsistent
475 * state, so we use NMIs as IPIs to tell the other CPUs to disable
478 * For safety, we will avoid running the nmi_shootdown_cpus()
479 * stuff unnecessarily, but we don't have a way to check
480 * if other CPUs have VMX enabled. So we will call it only if the
481 * CPU we are running on has VMX enabled.
483 * We will miss cases where VMX is not enabled on all CPUs. This
484 * shouldn't do much harm because KVM always enable VMX on all
485 * CPUs anyway. But we can miss it on the small window where KVM
486 * is still enabling VMX.
488 if (cpu_has_vmx() && cpu_vmx_enabled()) {
489 /* Disable VMX on this CPU. */
492 /* Halt and disable VMX on the other CPUs */
493 nmi_shootdown_cpus(vmxoff_nmi);
499 void __attribute__((weak)) mach_reboot_fixups(void)
504 * To the best of our knowledge Windows compatible x86 hardware expects
505 * the following on reboot:
507 * 1) If the FADT has the ACPI reboot register flag set, try it
508 * 2) If still alive, write to the keyboard controller
509 * 3) If still alive, write to the ACPI reboot register again
510 * 4) If still alive, write to the keyboard controller again
511 * 5) If still alive, call the EFI runtime service to reboot
512 * 6) If no EFI runtime service, call the BIOS to do a reboot
514 * We default to following the same pattern. We also have
515 * two other reboot methods: 'triple fault' and 'PCI', which
516 * can be triggered via the reboot= kernel boot option or
519 * This means that this function can never return, it can misbehave
520 * by not rebooting properly and hanging.
522 static void native_machine_emergency_restart(void)
526 int orig_reboot_type = reboot_type;
529 if (reboot_emergency)
530 emergency_vmx_disable_all();
532 tboot_shutdown(TB_SHUTDOWN_REBOOT);
534 /* Tell the BIOS if we want cold or warm reboot */
535 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
536 *((unsigned short *)__va(0x472)) = mode;
539 * If an EFI capsule has been registered with the firmware then
540 * override the reboot= parameter.
542 if (efi_capsule_pending(NULL)) {
543 pr_info("EFI capsule is pending, forcing EFI reboot.\n");
544 reboot_type = BOOT_EFI;
548 /* Could also try the reset bit in the Hammer NB */
549 switch (reboot_type) {
552 reboot_type = BOOT_KBD;
556 mach_reboot_fixups(); /* For board specific fixups */
558 for (i = 0; i < 10; i++) {
561 outb(0xfe, 0x64); /* Pulse reset low */
564 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
566 reboot_type = BOOT_ACPI;
568 reboot_type = BOOT_EFI;
573 efi_reboot(reboot_mode, NULL);
574 reboot_type = BOOT_BIOS;
578 machine_real_restart(MRR_BIOS);
580 /* We're probably dead after this, but... */
581 reboot_type = BOOT_CF9_SAFE;
585 port_cf9_safe = true;
590 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E;
591 u8 cf9 = inb(0xcf9) & ~reboot_code;
592 outb(cf9|2, 0xcf9); /* Request hard reset */
594 /* Actually do the reset */
595 outb(cf9|reboot_code, 0xcf9);
598 reboot_type = BOOT_TRIPLE;
603 __asm__ __volatile__("int3");
605 /* We're probably dead after this, but... */
606 reboot_type = BOOT_KBD;
612 void native_machine_shutdown(void)
614 /* Stop the cpus and apics */
615 #ifdef CONFIG_X86_IO_APIC
617 * Disabling IO APIC before local APIC is a workaround for
618 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
619 * Specification Update". In this situation, interrupts that target
620 * a Logical Processor whose Local APIC is either in the process of
621 * being hardware disabled or software disabled are neither delivered
622 * nor discarded. When this erratum occurs, the processor may hang.
624 * Even without the erratum, it still makes sense to quiet IO APIC
625 * before disabling Local APIC.
632 * Stop all of the others. Also disable the local irq to
633 * not receive the per-cpu timer interrupt which may trigger
634 * scheduler's load balance.
642 #ifdef CONFIG_HPET_TIMER
647 x86_platform.iommu_shutdown();
651 static void __machine_emergency_restart(int emergency)
653 reboot_emergency = emergency;
654 machine_ops.emergency_restart();
657 static void native_machine_restart(char *__unused)
659 pr_notice("machine restart\n");
663 __machine_emergency_restart(0);
666 static void native_machine_halt(void)
668 /* Stop other cpus and apics */
671 tboot_shutdown(TB_SHUTDOWN_HALT);
676 static void native_machine_power_off(void)
683 /* A fallback in case there is no PM info available */
684 tboot_shutdown(TB_SHUTDOWN_HALT);
687 struct 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_CORE
694 .crash_shutdown = native_machine_crash_shutdown,
698 void machine_power_off(void)
700 machine_ops.power_off();
703 void machine_shutdown(void)
705 machine_ops.shutdown();
708 void machine_emergency_restart(void)
710 __machine_emergency_restart(1);
713 void machine_restart(char *cmd)
715 machine_ops.restart(cmd);
718 void machine_halt(void)
723 #ifdef CONFIG_KEXEC_CORE
724 void machine_crash_shutdown(struct pt_regs *regs)
726 machine_ops.crash_shutdown(regs);
731 #if defined(CONFIG_SMP)
733 /* This keeps a track of which one is crashing cpu. */
734 static int crashing_cpu;
735 static nmi_shootdown_cb shootdown_callback;
737 static atomic_t waiting_for_crash_ipi;
738 static int crash_ipi_issued;
740 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
744 cpu = raw_smp_processor_id();
747 * Don't do anything if this handler is invoked on crashing cpu.
748 * Otherwise, system will completely hang. Crashing cpu can get
749 * an NMI if system was initially booted with nmi_watchdog parameter.
751 if (cpu == crashing_cpu)
755 shootdown_callback(cpu, regs);
757 atomic_dec(&waiting_for_crash_ipi);
758 /* Assume hlt works */
766 static void smp_send_nmi_allbutself(void)
768 apic->send_IPI_allbutself(NMI_VECTOR);
772 * Halt all other CPUs, calling the specified function on each of them
774 * This function can be used to halt all other CPUs on crash
775 * or emergency reboot time. The function passed as parameter
776 * will be called inside a NMI handler on all CPUs.
778 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
783 /* Make a note of crashing cpu. Will be used in NMI callback. */
784 crashing_cpu = safe_smp_processor_id();
786 shootdown_callback = callback;
788 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
789 /* Would it be better to replace the trap vector here? */
790 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
791 NMI_FLAG_FIRST, "crash"))
792 return; /* Return what? */
794 * Ensure the new callback function is set before sending
799 smp_send_nmi_allbutself();
801 /* Kick CPUs looping in NMI context. */
802 WRITE_ONCE(crash_ipi_issued, 1);
804 msecs = 1000; /* Wait at most a second for the other cpus to stop */
805 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
810 /* Leave the nmi callback set */
814 * Check if the crash dumping IPI got issued and if so, call its callback
815 * directly. This function is used when we have already been in NMI handler.
818 void run_crash_ipi_callback(struct pt_regs *regs)
820 if (crash_ipi_issued)
821 crash_nmi_callback(0, regs);
824 /* Override the weak function in kernel/panic.c */
825 void nmi_panic_self_stop(struct pt_regs *regs)
828 /* If no CPU is preparing crash dump, we simply loop here. */
829 run_crash_ipi_callback(regs);
834 #else /* !CONFIG_SMP */
835 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
837 /* No other CPUs to shoot down */
840 void run_crash_ipi_callback(struct pt_regs *regs)