summaryrefslogtreecommitdiffstats
path: root/arch/ia64/kernel/crash.c
blob: 90ef338cf46fd93e1aacedc10c8bc5a7d18a226c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
/*
 * arch/ia64/kernel/crash.c
 *
 * Architecture specific (ia64) functions for kexec based crash dumps.
 *
 * Created by: Khalid Aziz <khalid.aziz@hp.com>
 * Copyright (C) 2005 Hewlett-Packard Development Company, L.P.
 * Copyright (C) 2005 Intel Corp	Zou Nan hai <nanhai.zou@intel.com>
 *
 */
#include <linux/smp.h>
#include <linux/delay.h>
#include <linux/crash_dump.h>
#include <linux/bootmem.h>
#include <linux/kexec.h>
#include <linux/elfcore.h>
#include <linux/sysctl.h>
#include <linux/init.h>
#include <linux/kdebug.h>

#include <asm/mca.h>

int kdump_status[NR_CPUS];
static atomic_t kdump_cpu_frozen;
atomic_t kdump_in_progress;
static int kdump_on_init = 1;
static int kdump_on_fatal_mca = 1;

static inline Elf64_Word
*append_elf_note(Elf64_Word *buf, char *name, unsigned type, void *data,
		size_t data_len)
{
	struct elf_note *note = (struct elf_note *)buf;
	note->n_namesz = strlen(name) + 1;
	note->n_descsz = data_len;
	note->n_type   = type;
	buf += (sizeof(*note) + 3)/4;
	memcpy(buf, name, note->n_namesz);
	buf += (note->n_namesz + 3)/4;
	memcpy(buf, data, data_len);
	buf += (data_len + 3)/4;
	return buf;
}

static void
final_note(void *buf)
{
	memset(buf, 0, sizeof(struct elf_note));
}

extern void ia64_dump_cpu_regs(void *);

static DEFINE_PER_CPU(struct elf_prstatus, elf_prstatus);

void
crash_save_this_cpu(void)
{
	void *buf;
	unsigned long cfm, sof, sol;

	int cpu = smp_processor_id();
	struct elf_prstatus *prstatus = &per_cpu(elf_prstatus, cpu);

	elf_greg_t *dst = (elf_greg_t *)&(prstatus->pr_reg);
	memset(prstatus, 0, sizeof(*prstatus));
	prstatus->pr_pid = current->pid;

	ia64_dump_cpu_regs(dst);
	cfm = dst[43];
	sol = (cfm >> 7) & 0x7f;
	sof = cfm & 0x7f;
	dst[46] = (unsigned long)ia64_rse_skip_regs((unsigned long *)dst[46],
			sof - sol);

	buf = (u64 *) per_cpu_ptr(crash_notes, cpu);
	if (!buf)
		return;
	buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS, prstatus,
			sizeof(*prstatus));
	final_note(buf);
}

#ifdef CONFIG_SMP
static int
kdump_wait_cpu_freeze(void)
{
	int cpu_num = num_online_cpus() - 1;
	int timeout = 1000;
	while(timeout-- > 0) {
		if (atomic_read(&kdump_cpu_frozen) == cpu_num)
			return 0;
		udelay(1000);
	}
	return 1;
}
#endif

void
machine_crash_shutdown(struct pt_regs *pt)
{
	/* This function is only called after the system
	 * has paniced or is otherwise in a critical state.
	 * The minimum amount of code to allow a kexec'd kernel
	 * to run successfully needs to happen here.
	 *
	 * In practice this means shooting down the other cpus in
	 * an SMP system.
	 */
	kexec_disable_iosapic();
#ifdef CONFIG_SMP
	kdump_smp_send_stop();
	/* not all cpu response to IPI, send INIT to freeze them */
	if (kdump_wait_cpu_freeze() && kdump_on_init) 	{
		kdump_smp_send_init();
	}
#endif
}

static void
machine_kdump_on_init(void)
{
	crash_save_vmcoreinfo();
	local_irq_disable();
	kexec_disable_iosapic();
	machine_kexec(ia64_kimage);
}

void
kdump_cpu_freeze(struct unw_frame_info *info, void *arg)
{
	int cpuid;
	local_irq_disable();
	cpuid = smp_processor_id();
	crash_save_this_cpu();
	current->thread.ksp = (__u64)info->sw - 16;
	atomic_inc(&kdump_cpu_frozen);
	kdump_status[cpuid] = 1;
	mb();
#ifdef CONFIG_HOTPLUG_CPU
	if (cpuid != 0)
		ia64_jump_to_sal(&sal_boot_rendez_state[cpuid]);
#endif
	for (;;)
		cpu_relax();
}

static int
kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data)
{
	struct ia64_mca_notify_die *nd;
	struct die_args *args = data;

	if (!kdump_on_init && !kdump_on_fatal_mca)
		return NOTIFY_DONE;

	if (!ia64_kimage) {
		if (val == DIE_INIT_MONARCH_LEAVE)
			ia64_mca_printk(KERN_NOTICE
					"%s: kdump not configured\n",
					__func__);
		return NOTIFY_DONE;
	}

	if (val != DIE_INIT_MONARCH_LEAVE &&
	    val != DIE_INIT_SLAVE_LEAVE &&
	    val != DIE_INIT_MONARCH_PROCESS &&
	    val != DIE_MCA_RENDZVOUS_LEAVE &&
	    val != DIE_MCA_MONARCH_LEAVE)
		return NOTIFY_DONE;

	nd = (struct ia64_mca_notify_die *)args->err;
	/* Reason code 1 means machine check rendezvous*/
	if ((val == DIE_INIT_MONARCH_LEAVE || val == DIE_INIT_SLAVE_LEAVE
	    || val == DIE_INIT_MONARCH_PROCESS) && nd->sos->rv_rc == 1)
		return NOTIFY_DONE;

	switch (val) {
	case DIE_INIT_MONARCH_PROCESS:
		if (kdump_on_init) {
			atomic_set(&kdump_in_progress, 1);
			*(nd->monarch_cpu) = -1;
		}
		break;
	case DIE_INIT_MONARCH_LEAVE:
		if (kdump_on_init)
			machine_kdump_on_init();
		break;
	case DIE_INIT_SLAVE_LEAVE:
		if (atomic_read(&kdump_in_progress))
			unw_init_running(kdump_cpu_freeze, NULL);
		break;
	case DIE_MCA_RENDZVOUS_LEAVE:
		if (atomic_read(&kdump_in_progress))
			unw_init_running(kdump_cpu_freeze, NULL);
		break;
	case DIE_MCA_MONARCH_LEAVE:
		/* die_register->signr indicate if MCA is recoverable */
		if (kdump_on_fatal_mca && !args->signr) {
			atomic_set(&kdump_in_progress, 1);
			*(nd->monarch_cpu) = -1;
			machine_kdump_on_init();
		}
		break;
	}
	return NOTIFY_DONE;
}

#ifdef CONFIG_SYSCTL
static ctl_table kdump_ctl_table[] = {
	{
		.ctl_name = CTL_UNNUMBERED,
		.procname = "kdump_on_init",
		.data = &kdump_on_init,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = &proc_dointvec,
	},
	{
		.ctl_name = CTL_UNNUMBERED,
		.procname = "kdump_on_fatal_mca",
		.data = &kdump_on_fatal_mca,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = &proc_dointvec,
	},
	{ .ctl_name = 0 }
};

static ctl_table sys_table[] = {
	{
	  .ctl_name = CTL_KERN,
	  .procname = "kernel",
	  .mode = 0555,
	  .child = kdump_ctl_table,
	},
	{ .ctl_name = 0 }
};
#endif

static int
machine_crash_setup(void)
{
	/* be notified before default_monarch_init_process */
	static struct notifier_block kdump_init_notifier_nb = {
		.notifier_call = kdump_init_notifier,
		.priority = 1,
	};
	int ret;
	if((ret = register_die_notifier(&kdump_init_notifier_nb)) != 0)
		return ret;
#ifdef CONFIG_SYSCTL
	register_sysctl_table(sys_table);
#endif
	return 0;
}

__initcall(machine_crash_setup);

OpenPOWER on IntegriCloud