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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}
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/types.h>
11#include <linux/kernel.h>
12#include <linux/smp.h>
13#include <linux/reboot.h>
14#include <linux/kexec.h>
15#include <linux/delay.h>
16#include <linux/elf.h>
17#include <linux/elfcore.h>
18#include <linux/module.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/*
34 * This is used to VMCLEAR all VMCSs loaded on the
35 * processor. And when loading kvm_intel module, the
36 * callback function pointer will be assigned.
37 *
38 * protected by rcu.
39 */
40crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss = NULL;
41EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
42
43static inline void cpu_crash_vmclear_loaded_vmcss(void)
44{
45 crash_vmclear_fn *do_vmclear_operation = NULL;
46
47 rcu_read_lock();
48 do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);
49 if (do_vmclear_operation)
50 do_vmclear_operation();
51 rcu_read_unlock();
52}
53
54#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
55
56static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
57{
58#ifdef CONFIG_X86_32
59 struct pt_regs fixed_regs;
60
61 if (!user_mode_vm(regs)) {
62 crash_fixup_ss_esp(&fixed_regs, regs);
63 regs = &fixed_regs;
64 }
65#endif
66 crash_save_cpu(regs, cpu);
67
68 /*
69 * VMCLEAR VMCSs loaded on all cpus if needed.
70 */
71 cpu_crash_vmclear_loaded_vmcss();
72
73 /* Disable VMX or SVM if needed.
74 *
75 * We need to disable virtualization on all CPUs.
76 * Having VMX or SVM enabled on any CPU may break rebooting
77 * after the kdump kernel has finished its task.
78 */
79 cpu_emergency_vmxoff();
80 cpu_emergency_svm_disable();
81
82 disable_local_APIC();
83}
84
85static void kdump_nmi_shootdown_cpus(void)
86{
87 in_crash_kexec = 1;
88 nmi_shootdown_cpus(kdump_nmi_callback);
89
90 disable_local_APIC();
91}
92
93#else
94static void kdump_nmi_shootdown_cpus(void)
95{
96 /* There are no cpus to shootdown */
97}
98#endif
99
100void native_machine_crash_shutdown(struct pt_regs *regs)
101{
102 /* This function is only called after the system
103 * has panicked or is otherwise in a critical state.
104 * The minimum amount of code to allow a kexec'd kernel
105 * to run successfully needs to happen here.
106 *
107 * In practice this means shooting down the other cpus in
108 * an SMP system.
109 */
110 /* The kernel is broken so disable interrupts */
111 local_irq_disable();
112
113 kdump_nmi_shootdown_cpus();
114
115 /*
116 * VMCLEAR VMCSs loaded on this cpu if needed.
117 */
118 cpu_crash_vmclear_loaded_vmcss();
119
120 /* Booting kdump kernel with VMX or SVM enabled won't work,
121 * because (among other limitations) we can't disable paging
122 * with the virt flags.
123 */
124 cpu_emergency_vmxoff();
125 cpu_emergency_svm_disable();
126
127#ifdef CONFIG_X86_IO_APIC
128 /* Prevent crash_kexec() from deadlocking on ioapic_lock. */
129 ioapic_zap_locks();
130 disable_IO_APIC();
131#endif
132 lapic_shutdown();
133#ifdef CONFIG_HPET_TIMER
134 hpet_disable();
135#endif
136 crash_save_cpu(regs, safe_smp_processor_id());
137}