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/smp.h> 28 #include <asm/reboot.h> 29 #include <asm/virtext.h> 30 31 #include <mach_ipi.h> 32 33 34 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) 35 36 static void kdump_nmi_callback(int cpu, struct die_args *args) 37 { 38 struct pt_regs *regs; 39 #ifdef CONFIG_X86_32 40 struct pt_regs fixed_regs; 41 #endif 42 43 regs = args->regs; 44 45 #ifdef CONFIG_X86_32 46 if (!user_mode_vm(regs)) { 47 crash_fixup_ss_esp(&fixed_regs, regs); 48 regs = &fixed_regs; 49 } 50 #endif 51 crash_save_cpu(regs, cpu); 52 53 /* Disable VMX or SVM if needed. 54 * 55 * We need to disable virtualization on all CPUs. 56 * Having VMX or SVM enabled on any CPU may break rebooting 57 * after the kdump kernel has finished its task. 58 */ 59 cpu_emergency_vmxoff(); 60 cpu_emergency_svm_disable(); 61 62 disable_local_APIC(); 63 } 64 65 static void kdump_nmi_shootdown_cpus(void) 66 { 67 nmi_shootdown_cpus(kdump_nmi_callback); 68 69 disable_local_APIC(); 70 } 71 72 #else 73 static void kdump_nmi_shootdown_cpus(void) 74 { 75 /* There are no cpus to shootdown */ 76 } 77 #endif 78 79 void 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