1 // SPDX-License-Identifier: GPL-2.0
5 #include <linux/reboot.h>
16 #include <acpi/reboot.h>
24 #include <asm/reboot.h>
53  * Reboot options and system auto-detection code provided by
54  * Dell Inc. so their systems "just work". :-)
58  * Some machines require the "reboot=a" commandline options
64 		pr_info("%s series board detected. Selecting %s-method for reboots.\n",  in set_acpi_reboot()
65 			d->ident, "ACPI");  in set_acpi_reboot()
71  * Some machines require the "reboot=b" or "reboot=k"  commandline options,
78 		pr_info("%s series board detected. Selecting %s-method for reboots.\n",  in set_bios_reboot()
79 			d->ident, "BIOS");  in set_bios_reboot()
85  * Some machines don't handle the default ACPI reboot method and
86  * require the EFI reboot method:
92 		pr_info("%s series board detected. Selecting EFI-method for reboot.\n", d->ident);  in set_efi_reboot()
103 	 * routine will recognize as telling it to do a proper reboot.  (Well  in machine_real_restart()
104 	 * that's what this book in front of me says -- it may only apply to  in machine_real_restart()
109 	 * safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)  in machine_real_restart()
120 	/* Jump to the identity-mapped low memory code */  in machine_real_restart()
123 		     "rm" (real_mode_header->machine_real_restart_asm),  in machine_real_restart()
127 		     "m" (real_mode_header->machine_real_restart_asm),  in machine_real_restart()
138  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
144 		pr_info("%s series board detected. Selecting %s-method for reboots.\n",  in set_pci_reboot()
145 			d->ident, "PCI");  in set_pci_reboot()
154 		pr_info("%s series board detected. Selecting %s-method for reboot.\n",  in set_kbd_reboot()
155 			d->ident, "KBD");  in set_kbd_reboot()
161  * This is a single dmi_table handling all reboot quirks.
166 	{	/* Handle reboot issue on Acer Aspire one */
174 	{	/* Handle reboot issue on Acer TravelMate X514-51T */
176 		.ident = "Acer TravelMate X514-51T",
179 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate X514-51T"),
234 	{	/* Handle problems with rebooting on ASRock Q1900DC-ITX */
236 		.ident = "ASRock Q1900DC-ITX",
239 			DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"),
463 	/* Hewlett-Packard */
468 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
473 	{	/* PCIe Wifi card isn't detected after reboot otherwise */
478 			DMI_MATCH(DMI_PRODUCT_NAME, "ZBOX-CI327NANO-GS-01"),
483 	{	/* Handle problems with rebooting on Sony VGN-Z540N */
485 		.ident = "Sony VGN-Z540N",
488 			DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
509 	 * runtime services are enabled, force EFI reboot.  in reboot_init()
534 /* RCU-protected callback to disable virtualization prior to reboot. */
558  * reboot.  VMX blocks INIT if the CPU is post-VMXON, and SVM blocks INIT if
611  * the following on reboot:
613  * 1) If the FADT has the ACPI reboot register flag set, try it
615  * 3) If still alive, write to the ACPI reboot register again
617  * 5) If still alive, call the EFI runtime service to reboot
618  * 6) If no EFI runtime service, call the BIOS to do a reboot
621  * two other reboot methods: 'triple fault' and 'PCI', which
622  * can be triggered via the reboot= kernel boot option or
633 	unsigned short mode;  in native_machine_emergency_restart()  local
640 	/* Tell the BIOS if we want cold or warm reboot */  in native_machine_emergency_restart()
641 	mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0;  in native_machine_emergency_restart()
642 	*((unsigned short *)__va(0x472)) = mode;  in native_machine_emergency_restart()
646 	 * override the reboot= parameter.  in native_machine_emergency_restart()
649 		pr_info("EFI capsule is pending, forcing EFI reboot.\n");  in native_machine_emergency_restart()
722 	 * interrupts are enabled. This will allow all in-flight memory  in native_machine_shutdown()
747 	 * not receive the per-cpu timer interrupt which may trigger  in native_machine_shutdown()
849 int crashing_cpu = -1;
877 	 * Prepare the CPU for reboot _after_ invoking the callback so that the  in crash_nmi_callback()
898  * nmi_shootdown_cpus - Stop other CPUs via NMI
903  * INIT is recognized during reboot.
916 	 * Avoid certain doom if a shootdown already occurred; re-registering  in nmi_shootdown_cpus()
928 	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);  in nmi_shootdown_cpus()
947 		msecs--;  in nmi_shootdown_cpus()
951 	 * Leave the nmi callback set, shootdown is a one-time thing.  Clearing  in nmi_shootdown_cpus()