Commit | Line | Data |
---|---|---|
5033cba0 | 1 | /* |
62a31a03 | 2 | * Architecture specific (i386/x86_64) functions for kexec based crash dumps. |
5033cba0 EB |
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> | |
5033cba0 EB |
14 | #include <linux/reboot.h> |
15 | #include <linux/kexec.h> | |
5033cba0 EB |
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> | |
19842d67 | 24 | #include <asm/apic.h> |
0c1b2724 | 25 | #include <asm/hpet.h> |
1eeb66a1 | 26 | #include <linux/kdebug.h> |
ce53af94 | 27 | #include <asm/smp.h> |
ed23dc6f | 28 | #include <asm/reboot.h> |
2fbe7b25 | 29 | |
c4ac4263 | 30 | #include <mach_ipi.h> |
5033cba0 | 31 | |
b2bbe71b EH |
32 | #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) |
33 | ||
a3ea8ac8 VG |
34 | /* This keeps a track of which one is crashing cpu. */ |
35 | static int crashing_cpu; | |
5033cba0 | 36 | |
c4ac4263 EB |
37 | static atomic_t waiting_for_crash_ipi; |
38 | ||
a7d41820 | 39 | static void kdump_nmi_callback(int cpu, struct die_args *args) |
c4ac4263 | 40 | { |
2fbe7b25 | 41 | struct pt_regs *regs; |
1fb473d8 | 42 | #ifdef CONFIG_X86_32 |
4d55476c | 43 | struct pt_regs fixed_regs; |
62a31a03 | 44 | #endif |
a7d41820 EH |
45 | |
46 | regs = args->regs; | |
47 | ||
48 | #ifdef CONFIG_X86_32 | |
49 | if (!user_mode_vm(regs)) { | |
50 | crash_fixup_ss_esp(&fixed_regs, regs); | |
51 | regs = &fixed_regs; | |
52 | } | |
53 | #endif | |
54 | crash_save_cpu(regs, cpu); | |
55 | ||
56 | disable_local_APIC(); | |
57 | } | |
58 | ||
59 | static int crash_nmi_callback(struct notifier_block *self, | |
60 | unsigned long val, void *data) | |
61 | { | |
2fbe7b25 DZ |
62 | int cpu; |
63 | ||
260d6790 | 64 | if (val != DIE_NMI_IPI) |
2fbe7b25 DZ |
65 | return NOTIFY_OK; |
66 | ||
2fbe7b25 | 67 | cpu = raw_smp_processor_id(); |
a3ea8ac8 VG |
68 | |
69 | /* Don't do anything if this handler is invoked on crashing cpu. | |
70 | * Otherwise, system will completely hang. Crashing cpu can get | |
71 | * an NMI if system was initially booted with nmi_watchdog parameter. | |
72 | */ | |
73 | if (cpu == crashing_cpu) | |
260d6790 | 74 | return NOTIFY_STOP; |
c4ac4263 | 75 | local_irq_disable(); |
4d55476c | 76 | |
a7d41820 EH |
77 | kdump_nmi_callback(cpu, (struct die_args *)data); |
78 | ||
c4ac4263 EB |
79 | atomic_dec(&waiting_for_crash_ipi); |
80 | /* Assume hlt works */ | |
f2ab4461 | 81 | halt(); |
caad3c2a CE |
82 | for (;;) |
83 | cpu_relax(); | |
72414d3f | 84 | |
c4ac4263 EB |
85 | return 1; |
86 | } | |
87 | ||
c4ac4263 EB |
88 | static void smp_send_nmi_allbutself(void) |
89 | { | |
bc03613d FV |
90 | cpumask_t mask = cpu_online_map; |
91 | cpu_clear(safe_smp_processor_id(), mask); | |
92 | if (!cpus_empty(mask)) | |
93 | send_IPI_mask(mask, NMI_VECTOR); | |
c4ac4263 EB |
94 | } |
95 | ||
2fbe7b25 DZ |
96 | static struct notifier_block crash_nmi_nb = { |
97 | .notifier_call = crash_nmi_callback, | |
98 | }; | |
99 | ||
c4ac4263 EB |
100 | static void nmi_shootdown_cpus(void) |
101 | { | |
102 | unsigned long msecs; | |
c4ac4263 | 103 | |
b2bbe71b EH |
104 | /* Make a note of crashing cpu. Will be used in NMI callback.*/ |
105 | crashing_cpu = safe_smp_processor_id(); | |
106 | ||
72414d3f | 107 | atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); |
c4ac4263 | 108 | /* Would it be better to replace the trap vector here? */ |
2fbe7b25 DZ |
109 | if (register_die_notifier(&crash_nmi_nb)) |
110 | return; /* return what? */ | |
c4ac4263 EB |
111 | /* Ensure the new callback function is set before sending |
112 | * out the NMI | |
113 | */ | |
114 | wmb(); | |
115 | ||
116 | smp_send_nmi_allbutself(); | |
117 | ||
118 | msecs = 1000; /* Wait at most a second for the other cpus to stop */ | |
119 | while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { | |
120 | mdelay(1); | |
121 | msecs--; | |
122 | } | |
123 | ||
124 | /* Leave the nmi callback set */ | |
d1e7b91c EH |
125 | } |
126 | ||
127 | static void kdump_nmi_shootdown_cpus(void) | |
128 | { | |
129 | nmi_shootdown_cpus(); | |
130 | ||
19842d67 | 131 | disable_local_APIC(); |
c4ac4263 | 132 | } |
d1e7b91c | 133 | |
c4ac4263 | 134 | #else |
d1e7b91c | 135 | static void kdump_nmi_shootdown_cpus(void) |
c4ac4263 EB |
136 | { |
137 | /* There are no cpus to shootdown */ | |
138 | } | |
139 | #endif | |
140 | ||
ed23dc6f | 141 | void native_machine_crash_shutdown(struct pt_regs *regs) |
5033cba0 EB |
142 | { |
143 | /* This function is only called after the system | |
f18190bd | 144 | * has panicked or is otherwise in a critical state. |
5033cba0 EB |
145 | * The minimum amount of code to allow a kexec'd kernel |
146 | * to run successfully needs to happen here. | |
147 | * | |
148 | * In practice this means shooting down the other cpus in | |
149 | * an SMP system. | |
150 | */ | |
c4ac4263 EB |
151 | /* The kernel is broken so disable interrupts */ |
152 | local_irq_disable(); | |
a3ea8ac8 | 153 | |
d1e7b91c | 154 | kdump_nmi_shootdown_cpus(); |
19842d67 VG |
155 | lapic_shutdown(); |
156 | #if defined(CONFIG_X86_IO_APIC) | |
157 | disable_IO_APIC(); | |
0c1b2724 OH |
158 | #endif |
159 | #ifdef CONFIG_HPET_TIMER | |
160 | hpet_disable(); | |
19842d67 | 161 | #endif |
85916f81 | 162 | crash_save_cpu(regs, safe_smp_processor_id()); |
5033cba0 | 163 | } |