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>
17 #include <asm/pgtable.h>
18 #include <asm/proto.h>
19 #include <asm/reboot_fixups.h>
20 #include <asm/reboot.h>
21 #include <asm/pci_x86.h>
22 #include <asm/virtext.h>
27 #include <linux/ctype.h>
28 #include <linux/mc146818rtc.h>
29 #include <asm/realmode.h>
30 #include <asm/x86_init.h>
33 * Power off function, if any
35 void (*pm_power_off)(void);
36 EXPORT_SYMBOL(pm_power_off);
38 static const struct desc_ptr no_idt = {};
39 static enum reboot_mode reboot_mode;
40 enum reboot_type reboot_type = BOOT_ACPI;
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.
50 static int reboot_default = 1;
53 static int reboot_cpu = -1;
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
61 static int reboot_emergency;
63 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
64 bool port_cf9_safe = false;
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
71 * smp Reboot by executing reset on BSP or other CPU
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.
79 static int __init reboot_setup(char *str)
83 * Having anything passed on the command line via
84 * reboot= will cause us to disable DMI checking
91 reboot_mode = REBOOT_WARM;
95 reboot_mode = REBOOT_COLD;
100 if (isdigit(*(str+1))) {
101 reboot_cpu = (int) (*(str+1) - '0');
102 if (isdigit(*(str+2)))
103 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
106 * We will leave sorting out the final value
107 * when we are ready to reboot, since we might not
108 * have detected BSP APIC ID or smp_num_cpu
111 #endif /* CONFIG_SMP */
127 str = strchr(str, ',');
136 __setup("reboot=", reboot_setup);
140 * Reboot options and system auto-detection code provided by
141 * Dell Inc. so their systems "just work". :-)
145 * Some machines require the "reboot=b" or "reboot=k" commandline options,
146 * this quirk makes that automatic.
148 static int __init set_bios_reboot(const struct dmi_system_id *d)
150 if (reboot_type != BOOT_BIOS) {
151 reboot_type = BOOT_BIOS;
152 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
158 void __noreturn machine_real_restart(unsigned int type)
163 * Write zero to CMOS register number 0x0f, which the BIOS POST
164 * routine will recognize as telling it to do a proper reboot. (Well
165 * that's what this book in front of me says -- it may only apply to
166 * the Phoenix BIOS though, it's not clear). At the same time,
167 * disable NMIs by setting the top bit in the CMOS address register,
168 * as we're about to do peculiar things to the CPU. I'm not sure if
169 * `outb_p' is needed instead of just `outb'. Use it to be on the
170 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
172 spin_lock(&rtc_lock);
173 CMOS_WRITE(0x00, 0x8f);
174 spin_unlock(&rtc_lock);
177 * Switch back to the initial page table.
180 load_cr3(initial_page_table);
182 write_cr3(real_mode_header->trampoline_pgd);
185 /* Jump to the identity-mapped low memory code */
187 asm volatile("jmpl *%0" : :
188 "rm" (real_mode_header->machine_real_restart_asm),
191 asm volatile("ljmpl *%0" : :
192 "m" (real_mode_header->machine_real_restart_asm),
197 #ifdef CONFIG_APM_MODULE
198 EXPORT_SYMBOL(machine_real_restart);
202 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
204 static int __init set_pci_reboot(const struct dmi_system_id *d)
206 if (reboot_type != BOOT_CF9) {
207 reboot_type = BOOT_CF9;
208 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
214 static int __init set_kbd_reboot(const struct dmi_system_id *d)
216 if (reboot_type != BOOT_KBD) {
217 reboot_type = BOOT_KBD;
218 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
225 * This is a single dmi_table handling all reboot quirks.
227 static struct dmi_system_id __initdata reboot_dmi_table[] = {
228 { /* Handle problems with rebooting on Dell E520's */
229 .callback = set_bios_reboot,
230 .ident = "Dell E520",
232 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
233 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
236 { /* Handle problems with rebooting on Dell 1300's */
237 .callback = set_bios_reboot,
238 .ident = "Dell PowerEdge 1300",
240 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
241 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
244 { /* Handle problems with rebooting on Dell 300's */
245 .callback = set_bios_reboot,
246 .ident = "Dell PowerEdge 300",
248 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
249 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
252 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
253 .callback = set_bios_reboot,
254 .ident = "Dell OptiPlex 745",
256 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
257 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
260 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
261 .callback = set_bios_reboot,
262 .ident = "Dell OptiPlex 745",
264 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
265 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
266 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
269 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
270 .callback = set_bios_reboot,
271 .ident = "Dell OptiPlex 745",
273 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
274 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
275 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
278 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
279 .callback = set_bios_reboot,
280 .ident = "Dell OptiPlex 330",
282 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
283 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
284 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
287 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
288 .callback = set_bios_reboot,
289 .ident = "Dell OptiPlex 360",
291 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
292 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
293 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
296 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
297 .callback = set_bios_reboot,
298 .ident = "Dell OptiPlex 760",
300 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
301 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
302 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
305 { /* Handle problems with rebooting on Dell 2400's */
306 .callback = set_bios_reboot,
307 .ident = "Dell PowerEdge 2400",
309 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
310 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
313 { /* Handle problems with rebooting on Dell T5400's */
314 .callback = set_bios_reboot,
315 .ident = "Dell Precision T5400",
317 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
318 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
321 { /* Handle problems with rebooting on Dell T7400's */
322 .callback = set_bios_reboot,
323 .ident = "Dell Precision T7400",
325 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
326 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
329 { /* Handle problems with rebooting on HP laptops */
330 .callback = set_bios_reboot,
331 .ident = "HP Compaq Laptop",
333 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
334 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
337 { /* Handle problems with rebooting on Dell XPS710 */
338 .callback = set_bios_reboot,
339 .ident = "Dell XPS710",
341 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
342 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
345 { /* Handle problems with rebooting on Dell DXP061 */
346 .callback = set_bios_reboot,
347 .ident = "Dell DXP061",
349 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
350 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
353 { /* Handle problems with rebooting on Sony VGN-Z540N */
354 .callback = set_bios_reboot,
355 .ident = "Sony VGN-Z540N",
357 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
358 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
361 { /* Handle problems with rebooting on ASUS P4S800 */
362 .callback = set_bios_reboot,
363 .ident = "ASUS P4S800",
365 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
366 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
370 { /* Handle reboot issue on Acer Aspire one */
371 .callback = set_kbd_reboot,
372 .ident = "Acer Aspire One A110",
374 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
375 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
378 { /* Handle problems with rebooting on Apple MacBook5 */
379 .callback = set_pci_reboot,
380 .ident = "Apple MacBook5",
382 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
383 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
386 { /* Handle problems with rebooting on Apple MacBookPro5 */
387 .callback = set_pci_reboot,
388 .ident = "Apple MacBookPro5",
390 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
391 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
394 { /* Handle problems with rebooting on Apple Macmini3,1 */
395 .callback = set_pci_reboot,
396 .ident = "Apple Macmini3,1",
398 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
399 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
402 { /* Handle problems with rebooting on the iMac9,1. */
403 .callback = set_pci_reboot,
404 .ident = "Apple iMac9,1",
406 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
407 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
410 { /* Handle problems with rebooting on the Latitude E6320. */
411 .callback = set_pci_reboot,
412 .ident = "Dell Latitude E6320",
414 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
415 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
418 { /* Handle problems with rebooting on the Latitude E5420. */
419 .callback = set_pci_reboot,
420 .ident = "Dell Latitude E5420",
422 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
423 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
426 { /* Handle problems with rebooting on the Latitude E6420. */
427 .callback = set_pci_reboot,
428 .ident = "Dell Latitude E6420",
430 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
431 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
434 { /* Handle problems with rebooting on the OptiPlex 990. */
435 .callback = set_pci_reboot,
436 .ident = "Dell OptiPlex 990",
438 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
439 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
442 { /* Handle problems with rebooting on the Precision M6600. */
443 .callback = set_pci_reboot,
444 .ident = "Dell OptiPlex 990",
446 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
447 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"),
453 static int __init reboot_init(void)
456 * Only do the DMI check if reboot_type hasn't been overridden
457 * on the command line
460 dmi_check_system(reboot_dmi_table);
463 core_initcall(reboot_init);
465 static inline void kb_wait(void)
469 for (i = 0; i < 0x10000; i++) {
470 if ((inb(0x64) & 0x02) == 0)
476 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
478 cpu_emergency_vmxoff();
481 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
482 static void emergency_vmx_disable_all(void)
484 /* Just make sure we won't change CPUs while doing this */
488 * We need to disable VMX on all CPUs before rebooting, otherwise
489 * we risk hanging up the machine, because the CPU ignore INIT
490 * signals when VMX is enabled.
492 * We can't take any locks and we may be on an inconsistent
493 * state, so we use NMIs as IPIs to tell the other CPUs to disable
496 * For safety, we will avoid running the nmi_shootdown_cpus()
497 * stuff unnecessarily, but we don't have a way to check
498 * if other CPUs have VMX enabled. So we will call it only if the
499 * CPU we are running on has VMX enabled.
501 * We will miss cases where VMX is not enabled on all CPUs. This
502 * shouldn't do much harm because KVM always enable VMX on all
503 * CPUs anyway. But we can miss it on the small window where KVM
504 * is still enabling VMX.
506 if (cpu_has_vmx() && cpu_vmx_enabled()) {
507 /* Disable VMX on this CPU. */
510 /* Halt and disable VMX on the other CPUs */
511 nmi_shootdown_cpus(vmxoff_nmi);
517 void __attribute__((weak)) mach_reboot_fixups(void)
522 * Windows compatible x86 hardware expects the following on reboot:
524 * 1) If the FADT has the ACPI reboot register flag set, try it
525 * 2) If still alive, write to the keyboard controller
526 * 3) If still alive, write to the ACPI reboot register again
527 * 4) If still alive, write to the keyboard controller again
529 * If the machine is still alive at this stage, it gives up. We default to
530 * following the same pattern, except that if we're still alive after (4) we'll
531 * try to force a triple fault and then cycle between hitting the keyboard
532 * controller and doing that
534 static void native_machine_emergency_restart(void)
538 int orig_reboot_type = reboot_type;
541 if (reboot_emergency)
542 emergency_vmx_disable_all();
544 tboot_shutdown(TB_SHUTDOWN_REBOOT);
546 /* Tell the BIOS if we want cold or warm reboot */
547 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;
548 *((unsigned short *)__va(0x472)) = mode;
551 /* Could also try the reset bit in the Hammer NB */
552 switch (reboot_type) {
554 mach_reboot_fixups(); /* For board specific fixups */
556 for (i = 0; i < 10; i++) {
559 outb(0xfe, 0x64); /* Pulse reset low */
562 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
564 reboot_type = BOOT_ACPI;
566 reboot_type = BOOT_TRIPLE;
572 __asm__ __volatile__("int3");
574 reboot_type = BOOT_KBD;
578 machine_real_restart(MRR_BIOS);
580 reboot_type = BOOT_KBD;
585 reboot_type = BOOT_KBD;
589 if (efi_enabled(EFI_RUNTIME_SERVICES))
590 efi.reset_system(reboot_mode == REBOOT_WARM ?
593 EFI_SUCCESS, 0, NULL);
594 reboot_type = BOOT_KBD;
598 port_cf9_safe = true;
603 u8 cf9 = inb(0xcf9) & ~6;
604 outb(cf9|2, 0xcf9); /* Request hard reset */
606 outb(cf9|6, 0xcf9); /* Actually do the reset */
609 reboot_type = BOOT_KBD;
615 void native_machine_shutdown(void)
617 /* Stop the cpus and apics */
620 /* The boot cpu is always logical cpu 0 */
621 int reboot_cpu_id = 0;
623 /* See if there has been given a command line override */
624 if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
625 cpu_online(reboot_cpu))
626 reboot_cpu_id = reboot_cpu;
628 /* Make certain the cpu I'm about to reboot on is online */
629 if (!cpu_online(reboot_cpu_id))
630 reboot_cpu_id = smp_processor_id();
632 /* Make certain I only run on the appropriate processor */
633 set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
636 * O.K Now that I'm on the appropriate processor, stop all of the
637 * others. Also disable the local irq to not receive the per-cpu
638 * timer interrupt which may trigger scheduler's load balance.
646 #ifdef CONFIG_X86_IO_APIC
650 #ifdef CONFIG_HPET_TIMER
655 x86_platform.iommu_shutdown();
659 static void __machine_emergency_restart(int emergency)
661 reboot_emergency = emergency;
662 machine_ops.emergency_restart();
665 static void native_machine_restart(char *__unused)
667 pr_notice("machine restart\n");
671 __machine_emergency_restart(0);
674 static void native_machine_halt(void)
676 /* Stop other cpus and apics */
679 tboot_shutdown(TB_SHUTDOWN_HALT);
684 static void native_machine_power_off(void)
691 /* A fallback in case there is no PM info available */
692 tboot_shutdown(TB_SHUTDOWN_HALT);
695 struct machine_ops machine_ops = {
696 .power_off = native_machine_power_off,
697 .shutdown = native_machine_shutdown,
698 .emergency_restart = native_machine_emergency_restart,
699 .restart = native_machine_restart,
700 .halt = native_machine_halt,
702 .crash_shutdown = native_machine_crash_shutdown,
706 void machine_power_off(void)
708 machine_ops.power_off();
711 void machine_shutdown(void)
713 machine_ops.shutdown();
716 void machine_emergency_restart(void)
718 __machine_emergency_restart(1);
721 void machine_restart(char *cmd)
723 machine_ops.restart(cmd);
726 void machine_halt(void)
732 void machine_crash_shutdown(struct pt_regs *regs)
734 machine_ops.crash_shutdown(regs);
739 #if defined(CONFIG_SMP)
741 /* This keeps a track of which one is crashing cpu. */
742 static int crashing_cpu;
743 static nmi_shootdown_cb shootdown_callback;
745 static atomic_t waiting_for_crash_ipi;
747 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
751 cpu = raw_smp_processor_id();
754 * Don't do anything if this handler is invoked on crashing cpu.
755 * Otherwise, system will completely hang. Crashing cpu can get
756 * an NMI if system was initially booted with nmi_watchdog parameter.
758 if (cpu == crashing_cpu)
762 shootdown_callback(cpu, regs);
764 atomic_dec(&waiting_for_crash_ipi);
765 /* Assume hlt works */
773 static void smp_send_nmi_allbutself(void)
775 apic->send_IPI_allbutself(NMI_VECTOR);
779 * Halt all other CPUs, calling the specified function on each of them
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.
785 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
790 /* Make a note of crashing cpu. Will be used in NMI callback. */
791 crashing_cpu = safe_smp_processor_id();
793 shootdown_callback = callback;
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_nmi_handler(NMI_LOCAL, crash_nmi_callback,
798 NMI_FLAG_FIRST, "crash"))
799 return; /* Return what? */
801 * Ensure the new callback function is set before sending
806 smp_send_nmi_allbutself();
808 msecs = 1000; /* Wait at most a second for the other cpus to stop */
809 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
814 /* Leave the nmi callback set */
816 #else /* !CONFIG_SMP */
817 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
819 /* No other CPUs to shoot down */