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>
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 = {};
41 static int reboot_mode;
42 enum reboot_type reboot_type = BOOT_ACPI;
46 * This variable is used privately to keep track of whether or not
47 * reboot_type is still set to its default value (i.e., reboot= hasn't
48 * been set on the command line). This is needed so that we can
49 * suppress DMI scanning for reboot quirks. Without it, it's
50 * impossible to override a faulty reboot quirk without recompiling.
52 static int reboot_default = 1;
54 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
55 static int reboot_cpu = -1;
59 * This is set if we need to go through the 'emergency' path.
60 * When machine_emergency_restart() is called, we may be on
61 * an inconsistent state and won't be able to do a clean cleanup
63 static int reboot_emergency;
65 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
66 bool port_cf9_safe = false;
69 * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
70 * warm Don't set the cold reboot flag
71 * cold Set the cold reboot flag
72 * bios Reboot by jumping through the BIOS (only for X86_32)
73 * smp Reboot by executing reset on BSP or other CPU (only for X86_32)
74 * triple Force a triple fault (init)
75 * kbd Use the keyboard controller. cold reset (default)
76 * acpi Use the RESET_REG in the FADT
77 * efi Use efi reset_system runtime service
78 * pci Use the so-called "PCI reset register", CF9
79 * force Avoid anything that could hang.
81 static int __init reboot_setup(char *str)
85 * Having anything passed on the command line via
86 * reboot= will cause us to disable DMI checking
103 if (isdigit(*(str+1))) {
104 reboot_cpu = (int) (*(str+1) - '0');
105 if (isdigit(*(str+2)))
106 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
109 * We will leave sorting out the final value
110 * when we are ready to reboot, since we might not
111 * have detected BSP APIC ID or smp_num_cpu
114 #endif /* CONFIG_SMP */
131 str = strchr(str, ',');
140 __setup("reboot=", reboot_setup);
145 * Reboot options and system auto-detection code provided by
146 * Dell Inc. so their systems "just work". :-)
150 * Some machines require the "reboot=b" or "reboot=k" commandline options,
151 * this quirk makes that automatic.
153 static int __init set_bios_reboot(const struct dmi_system_id *d)
155 if (reboot_type != BOOT_BIOS) {
156 reboot_type = BOOT_BIOS;
157 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
163 void machine_real_restart(unsigned int type)
165 void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
166 real_mode_header->machine_real_restart_asm;
171 * Write zero to CMOS register number 0x0f, which the BIOS POST
172 * routine will recognize as telling it to do a proper reboot. (Well
173 * that's what this book in front of me says -- it may only apply to
174 * the Phoenix BIOS though, it's not clear). At the same time,
175 * disable NMIs by setting the top bit in the CMOS address register,
176 * as we're about to do peculiar things to the CPU. I'm not sure if
177 * `outb_p' is needed instead of just `outb'. Use it to be on the
178 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
180 spin_lock(&rtc_lock);
181 CMOS_WRITE(0x00, 0x8f);
182 spin_unlock(&rtc_lock);
185 * Switch back to the initial page table.
187 load_cr3(initial_page_table);
190 * Write 0x1234 to absolute memory location 0x472. The BIOS reads
191 * this on booting to tell it to "Bypass memory test (also warm
192 * boot)". This seems like a fairly standard thing that gets set by
193 * REBOOT.COM programs, and the previous reset routine did this
195 *((unsigned short *)0x472) = reboot_mode;
197 /* Jump to the identity-mapped low memory code */
198 restart_lowmem(type);
200 #ifdef CONFIG_APM_MODULE
201 EXPORT_SYMBOL(machine_real_restart);
204 #endif /* CONFIG_X86_32 */
207 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
209 static int __init set_pci_reboot(const struct dmi_system_id *d)
211 if (reboot_type != BOOT_CF9) {
212 reboot_type = BOOT_CF9;
213 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
219 static int __init set_kbd_reboot(const struct dmi_system_id *d)
221 if (reboot_type != BOOT_KBD) {
222 reboot_type = BOOT_KBD;
223 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
230 * This is a single dmi_table handling all reboot quirks. Note that
231 * REBOOT_BIOS is only available for 32bit
233 static struct dmi_system_id __initdata reboot_dmi_table[] = {
235 { /* Handle problems with rebooting on Dell E520's */
236 .callback = set_bios_reboot,
237 .ident = "Dell E520",
239 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
240 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
243 { /* Handle problems with rebooting on Dell 1300's */
244 .callback = set_bios_reboot,
245 .ident = "Dell PowerEdge 1300",
247 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
248 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
251 { /* Handle problems with rebooting on Dell 300's */
252 .callback = set_bios_reboot,
253 .ident = "Dell PowerEdge 300",
255 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
256 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
259 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
260 .callback = set_bios_reboot,
261 .ident = "Dell OptiPlex 745",
263 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
264 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
267 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
268 .callback = set_bios_reboot,
269 .ident = "Dell OptiPlex 745",
271 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
272 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
273 DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
276 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
277 .callback = set_bios_reboot,
278 .ident = "Dell OptiPlex 745",
280 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
281 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
282 DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
285 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
286 .callback = set_bios_reboot,
287 .ident = "Dell OptiPlex 330",
289 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
290 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
291 DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
294 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
295 .callback = set_bios_reboot,
296 .ident = "Dell OptiPlex 360",
298 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
299 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
300 DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
303 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
304 .callback = set_bios_reboot,
305 .ident = "Dell OptiPlex 760",
307 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
308 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
309 DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
312 { /* Handle problems with rebooting on Dell 2400's */
313 .callback = set_bios_reboot,
314 .ident = "Dell PowerEdge 2400",
316 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
317 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
320 { /* Handle problems with rebooting on Dell T5400's */
321 .callback = set_bios_reboot,
322 .ident = "Dell Precision T5400",
324 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
325 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
328 { /* Handle problems with rebooting on Dell T7400's */
329 .callback = set_bios_reboot,
330 .ident = "Dell Precision T7400",
332 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
333 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
336 { /* Handle problems with rebooting on HP laptops */
337 .callback = set_bios_reboot,
338 .ident = "HP Compaq Laptop",
340 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
341 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
344 { /* Handle problems with rebooting on Dell XPS710 */
345 .callback = set_bios_reboot,
346 .ident = "Dell XPS710",
348 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
349 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
352 { /* Handle problems with rebooting on Dell DXP061 */
353 .callback = set_bios_reboot,
354 .ident = "Dell DXP061",
356 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
357 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
360 { /* Handle problems with rebooting on Sony VGN-Z540N */
361 .callback = set_bios_reboot,
362 .ident = "Sony VGN-Z540N",
364 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
365 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
368 { /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
369 .callback = set_bios_reboot,
370 .ident = "CompuLab SBC-FITPC2",
372 DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
373 DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
376 { /* Handle problems with rebooting on ASUS P4S800 */
377 .callback = set_bios_reboot,
378 .ident = "ASUS P4S800",
380 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
381 DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
384 #endif /* CONFIG_X86_32 */
386 { /* Handle reboot issue on Acer Aspire one */
387 .callback = set_kbd_reboot,
388 .ident = "Acer Aspire One A110",
390 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
391 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
394 { /* Handle problems with rebooting on Apple MacBook5 */
395 .callback = set_pci_reboot,
396 .ident = "Apple MacBook5",
398 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
399 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
402 { /* Handle problems with rebooting on Apple MacBookPro5 */
403 .callback = set_pci_reboot,
404 .ident = "Apple MacBookPro5",
406 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
407 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
410 { /* Handle problems with rebooting on Apple Macmini3,1 */
411 .callback = set_pci_reboot,
412 .ident = "Apple Macmini3,1",
414 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
415 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
418 { /* Handle problems with rebooting on the iMac9,1. */
419 .callback = set_pci_reboot,
420 .ident = "Apple iMac9,1",
422 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
423 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
426 { /* Handle problems with rebooting on the Latitude E6320. */
427 .callback = set_pci_reboot,
428 .ident = "Dell Latitude E6320",
430 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
431 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
434 { /* Handle problems with rebooting on the Latitude E5420. */
435 .callback = set_pci_reboot,
436 .ident = "Dell Latitude E5420",
438 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
439 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
442 { /* Handle problems with rebooting on the Latitude E6420. */
443 .callback = set_pci_reboot,
444 .ident = "Dell Latitude E6420",
446 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
447 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
450 { /* Handle problems with rebooting on the OptiPlex 990. */
451 .callback = set_pci_reboot,
452 .ident = "Dell OptiPlex 990",
454 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
455 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
461 static int __init reboot_init(void)
464 * Only do the DMI check if reboot_type hasn't been overridden
465 * on the command line
468 dmi_check_system(reboot_dmi_table);
471 core_initcall(reboot_init);
473 static inline void kb_wait(void)
477 for (i = 0; i < 0x10000; i++) {
478 if ((inb(0x64) & 0x02) == 0)
484 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
486 cpu_emergency_vmxoff();
489 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
490 static void emergency_vmx_disable_all(void)
492 /* Just make sure we won't change CPUs while doing this */
496 * We need to disable VMX on all CPUs before rebooting, otherwise
497 * we risk hanging up the machine, because the CPU ignore INIT
498 * signals when VMX is enabled.
500 * We can't take any locks and we may be on an inconsistent
501 * state, so we use NMIs as IPIs to tell the other CPUs to disable
504 * For safety, we will avoid running the nmi_shootdown_cpus()
505 * stuff unnecessarily, but we don't have a way to check
506 * if other CPUs have VMX enabled. So we will call it only if the
507 * CPU we are running on has VMX enabled.
509 * We will miss cases where VMX is not enabled on all CPUs. This
510 * shouldn't do much harm because KVM always enable VMX on all
511 * CPUs anyway. But we can miss it on the small window where KVM
512 * is still enabling VMX.
514 if (cpu_has_vmx() && cpu_vmx_enabled()) {
515 /* Disable VMX on this CPU. */
518 /* Halt and disable VMX on the other CPUs */
519 nmi_shootdown_cpus(vmxoff_nmi);
525 void __attribute__((weak)) mach_reboot_fixups(void)
530 * Windows compatible x86 hardware expects the following on reboot:
532 * 1) If the FADT has the ACPI reboot register flag set, try it
533 * 2) If still alive, write to the keyboard controller
534 * 3) If still alive, write to the ACPI reboot register again
535 * 4) If still alive, write to the keyboard controller again
537 * If the machine is still alive at this stage, it gives up. We default to
538 * following the same pattern, except that if we're still alive after (4) we'll
539 * try to force a triple fault and then cycle between hitting the keyboard
540 * controller and doing that
542 static void native_machine_emergency_restart(void)
546 int orig_reboot_type = reboot_type;
548 if (reboot_emergency)
549 emergency_vmx_disable_all();
551 tboot_shutdown(TB_SHUTDOWN_REBOOT);
553 /* Tell the BIOS if we want cold or warm reboot */
554 *((unsigned short *)__va(0x472)) = reboot_mode;
557 /* Could also try the reset bit in the Hammer NB */
558 switch (reboot_type) {
560 mach_reboot_fixups(); /* For board specific fixups */
562 for (i = 0; i < 10; i++) {
565 outb(0xfe, 0x64); /* Pulse reset low */
568 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
570 reboot_type = BOOT_ACPI;
572 reboot_type = BOOT_TRIPLE;
578 __asm__ __volatile__("int3");
580 reboot_type = BOOT_KBD;
585 machine_real_restart(MRR_BIOS);
587 reboot_type = BOOT_KBD;
593 reboot_type = BOOT_KBD;
598 efi.reset_system(reboot_mode ?
601 EFI_SUCCESS, 0, NULL);
602 reboot_type = BOOT_KBD;
606 port_cf9_safe = true;
611 u8 cf9 = inb(0xcf9) & ~6;
612 outb(cf9|2, 0xcf9); /* Request hard reset */
614 outb(cf9|6, 0xcf9); /* Actually do the reset */
617 reboot_type = BOOT_KBD;
623 void native_machine_shutdown(void)
625 /* Stop the cpus and apics */
628 /* The boot cpu is always logical cpu 0 */
629 int reboot_cpu_id = 0;
632 /* See if there has been given a command line override */
633 if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
634 cpu_online(reboot_cpu))
635 reboot_cpu_id = reboot_cpu;
638 /* Make certain the cpu I'm about to reboot on is online */
639 if (!cpu_online(reboot_cpu_id))
640 reboot_cpu_id = smp_processor_id();
642 /* Make certain I only run on the appropriate processor */
643 set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
646 * O.K Now that I'm on the appropriate processor, stop all of the
647 * others. Also disable the local irq to not receive the per-cpu
648 * timer interrupt which may trigger scheduler's load balance.
656 #ifdef CONFIG_X86_IO_APIC
660 #ifdef CONFIG_HPET_TIMER
665 x86_platform.iommu_shutdown();
669 static void __machine_emergency_restart(int emergency)
671 reboot_emergency = emergency;
672 machine_ops.emergency_restart();
675 static void native_machine_restart(char *__unused)
677 pr_notice("machine restart\n");
681 __machine_emergency_restart(0);
684 static void native_machine_halt(void)
686 /* Stop other cpus and apics */
689 tboot_shutdown(TB_SHUTDOWN_HALT);
694 static void native_machine_power_off(void)
701 /* A fallback in case there is no PM info available */
702 tboot_shutdown(TB_SHUTDOWN_HALT);
705 struct machine_ops machine_ops = {
706 .power_off = native_machine_power_off,
707 .shutdown = native_machine_shutdown,
708 .emergency_restart = native_machine_emergency_restart,
709 .restart = native_machine_restart,
710 .halt = native_machine_halt,
712 .crash_shutdown = native_machine_crash_shutdown,
716 void machine_power_off(void)
718 machine_ops.power_off();
721 void machine_shutdown(void)
723 machine_ops.shutdown();
726 void machine_emergency_restart(void)
728 __machine_emergency_restart(1);
731 void machine_restart(char *cmd)
733 machine_ops.restart(cmd);
736 void machine_halt(void)
742 void machine_crash_shutdown(struct pt_regs *regs)
744 machine_ops.crash_shutdown(regs);
749 #if defined(CONFIG_SMP)
751 /* This keeps a track of which one is crashing cpu. */
752 static int crashing_cpu;
753 static nmi_shootdown_cb shootdown_callback;
755 static atomic_t waiting_for_crash_ipi;
757 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
761 cpu = raw_smp_processor_id();
764 * Don't do anything if this handler is invoked on crashing cpu.
765 * Otherwise, system will completely hang. Crashing cpu can get
766 * an NMI if system was initially booted with nmi_watchdog parameter.
768 if (cpu == crashing_cpu)
772 shootdown_callback(cpu, regs);
774 atomic_dec(&waiting_for_crash_ipi);
775 /* Assume hlt works */
783 static void smp_send_nmi_allbutself(void)
785 apic->send_IPI_allbutself(NMI_VECTOR);
789 * Halt all other CPUs, calling the specified function on each of them
791 * This function can be used to halt all other CPUs on crash
792 * or emergency reboot time. The function passed as parameter
793 * will be called inside a NMI handler on all CPUs.
795 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
800 /* Make a note of crashing cpu. Will be used in NMI callback. */
801 crashing_cpu = safe_smp_processor_id();
803 shootdown_callback = callback;
805 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
806 /* Would it be better to replace the trap vector here? */
807 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
808 NMI_FLAG_FIRST, "crash"))
809 return; /* Return what? */
811 * Ensure the new callback function is set before sending
816 smp_send_nmi_allbutself();
818 msecs = 1000; /* Wait at most a second for the other cpus to stop */
819 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
824 /* Leave the nmi callback set */
826 #else /* !CONFIG_SMP */
827 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
829 /* No other CPUs to shoot down */