1/* 2 * Architecture specific (i386/x86_64) functions for kexec based crash dumps. 3 * 4 * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) 5 * 6 * Copyright (C) IBM Corporation, 2004. All rights reserved. 7 * 8 */ 9 10#include <linux/init.h> 11#include <linux/types.h> 12#include <linux/kernel.h> 13#include <linux/smp.h> 14#include <linux/reboot.h> 15#include <linux/kexec.h> 16#include <linux/delay.h> 17#include <linux/elf.h> 18#include <linux/elfcore.h> 19 20#include <asm/processor.h> 21#include <asm/hardirq.h> 22#include <asm/nmi.h> 23#include <asm/hw_irq.h> 24#include <asm/apic.h> 25#include <asm/hpet.h> 26#include <linux/kdebug.h> 27#include <asm/cpu.h> 28#include <asm/reboot.h> 29#include <asm/virtext.h> 30 31int in_crash_kexec; 32 33#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) 34 35static void kdump_nmi_callback(int cpu, struct die_args *args) 36{ 37 struct pt_regs *regs; 38#ifdef CONFIG_X86_32 39 struct pt_regs fixed_regs; 40#endif 41 42 regs = args->regs; 43 44#ifdef CONFIG_X86_32 45 if (!user_mode_vm(regs)) { 46 crash_fixup_ss_esp(&fixed_regs, regs); 47 regs = &fixed_regs; 48 } 49#endif 50 crash_save_cpu(regs, cpu); 51 52 /* Disable VMX or SVM if needed. 53 * 54 * We need to disable virtualization on all CPUs. 55 * Having VMX or SVM enabled on any CPU may break rebooting 56 * after the kdump kernel has finished its task. 57 */ 58 cpu_emergency_vmxoff(); 59 cpu_emergency_svm_disable(); 60 61 disable_local_APIC(); 62} 63 64static void kdump_nmi_shootdown_cpus(void) 65{ 66 in_crash_kexec = 1; 67 nmi_shootdown_cpus(kdump_nmi_callback); 68 69 disable_local_APIC(); 70} 71 72#else 73static void kdump_nmi_shootdown_cpus(void) 74{ 75 /* There are no cpus to shootdown */ 76} 77#endif 78 79void native_machine_crash_shutdown(struct pt_regs *regs) 80{ 81 /* This function is only called after the system 82 * has panicked or is otherwise in a critical state. 83 * The minimum amount of code to allow a kexec'd kernel 84 * to run successfully needs to happen here. 85 * 86 * In practice this means shooting down the other cpus in 87 * an SMP system. 88 */ 89 /* The kernel is broken so disable interrupts */ 90 local_irq_disable(); 91 92 kdump_nmi_shootdown_cpus(); 93 94 /* Booting kdump kernel with VMX or SVM enabled won't work, 95 * because (among other limitations) we can't disable paging 96 * with the virt flags. 97 */ 98 cpu_emergency_vmxoff(); 99 cpu_emergency_svm_disable(); 100 101 lapic_shutdown(); 102#if defined(CONFIG_X86_IO_APIC) 103 disable_IO_APIC(); 104#endif 105#ifdef CONFIG_HPET_TIMER 106 hpet_disable(); 107#endif 108 crash_save_cpu(regs, safe_smp_processor_id()); 109} 110