1 // SPDX-License-Identifier: GPL-2.0
3 * arch/ia64/kernel/crash.c
5 * Architecture specific (ia64) functions for kexec based crash dumps.
7 * Created by: Khalid Aziz <khalid.aziz@hp.com>
8 * Copyright (C) 2005 Hewlett-Packard Development Company, L.P.
9 * Copyright (C) 2005 Intel Corp Zou Nan hai <nanhai.zou@intel.com>
12 #include <linux/smp.h>
13 #include <linux/delay.h>
14 #include <linux/crash_dump.h>
15 #include <linux/memblock.h>
16 #include <linux/kexec.h>
17 #include <linux/elfcore.h>
18 #include <linux/reboot.h>
19 #include <linux/sysctl.h>
20 #include <linux/init.h>
21 #include <linux/kdebug.h>
25 int kdump_status
[NR_CPUS
];
26 static atomic_t kdump_cpu_frozen
;
27 atomic_t kdump_in_progress
;
28 static int kdump_freeze_monarch
;
29 static int kdump_on_init
= 1;
30 static int kdump_on_fatal_mca
= 1;
32 extern void ia64_dump_cpu_regs(void *);
34 static DEFINE_PER_CPU(struct elf_prstatus
, elf_prstatus
);
37 crash_save_this_cpu(void)
40 unsigned long cfm
, sof
, sol
;
42 int cpu
= smp_processor_id();
43 struct elf_prstatus
*prstatus
= &per_cpu(elf_prstatus
, cpu
);
45 elf_greg_t
*dst
= (elf_greg_t
*)&(prstatus
->pr_reg
);
46 memset(prstatus
, 0, sizeof(*prstatus
));
47 prstatus
->pr_pid
= current
->pid
;
49 ia64_dump_cpu_regs(dst
);
51 sol
= (cfm
>> 7) & 0x7f;
53 dst
[46] = (unsigned long)ia64_rse_skip_regs((unsigned long *)dst
[46],
56 buf
= (u64
*) per_cpu_ptr(crash_notes
, cpu
);
59 buf
= append_elf_note(buf
, KEXEC_CORE_NOTE_NAME
, NT_PRSTATUS
, prstatus
,
66 kdump_wait_cpu_freeze(void)
68 int cpu_num
= num_online_cpus() - 1;
70 while(timeout
-- > 0) {
71 if (atomic_read(&kdump_cpu_frozen
) == cpu_num
)
80 machine_crash_shutdown(struct pt_regs
*pt
)
82 /* This function is only called after the system
83 * has paniced or is otherwise in a critical state.
84 * The minimum amount of code to allow a kexec'd kernel
85 * to run successfully needs to happen here.
87 * In practice this means shooting down the other cpus in
90 kexec_disable_iosapic();
93 * If kdump_on_init is set and an INIT is asserted here, kdump will
94 * be started again via INIT monarch.
97 ia64_set_psr_mc(); /* mask MCA/INIT */
98 if (atomic_inc_return(&kdump_in_progress
) != 1)
99 unw_init_running(kdump_cpu_freeze
, NULL
);
102 * Now this cpu is ready for kdump.
103 * Stop all others by IPI or INIT. They could receive INIT from
104 * outside and might be INIT monarch, but only thing they have to
105 * do is falling into kdump_cpu_freeze().
107 * If an INIT is asserted here:
108 * - All receivers might be slaves, since some of cpus could already
109 * be frozen and INIT might be masked on monarch. In this case,
110 * all slaves will be frozen soon since kdump_in_progress will let
111 * them into DIE_INIT_SLAVE_LEAVE.
112 * - One might be a monarch, but INIT rendezvous will fail since
113 * at least this cpu already have INIT masked so it never join
114 * to the rendezvous. In this case, all slaves and monarch will
115 * be frozen soon with no wait since the INIT rendezvous is skipped
116 * by kdump_in_progress.
118 kdump_smp_send_stop();
119 /* not all cpu response to IPI, send INIT to freeze them */
120 if (kdump_wait_cpu_freeze()) {
121 kdump_smp_send_init();
122 /* wait again, don't go ahead if possible */
123 kdump_wait_cpu_freeze();
129 machine_kdump_on_init(void)
131 crash_save_vmcoreinfo();
133 kexec_disable_iosapic();
134 machine_kexec(ia64_kimage
);
138 kdump_cpu_freeze(struct unw_frame_info
*info
, void *arg
)
143 cpuid
= smp_processor_id();
144 crash_save_this_cpu();
145 current
->thread
.ksp
= (__u64
)info
->sw
- 16;
147 ia64_set_psr_mc(); /* mask MCA/INIT and stop reentrance */
149 atomic_inc(&kdump_cpu_frozen
);
150 kdump_status
[cpuid
] = 1;
157 kdump_init_notifier(struct notifier_block
*self
, unsigned long val
, void *data
)
159 struct ia64_mca_notify_die
*nd
;
160 struct die_args
*args
= data
;
162 if (atomic_read(&kdump_in_progress
)) {
164 case DIE_INIT_MONARCH_LEAVE
:
165 if (!kdump_freeze_monarch
)
168 case DIE_INIT_SLAVE_LEAVE
:
169 case DIE_INIT_MONARCH_ENTER
:
170 case DIE_MCA_RENDZVOUS_LEAVE
:
171 unw_init_running(kdump_cpu_freeze
, NULL
);
176 if (!kdump_on_init
&& !kdump_on_fatal_mca
)
180 if (val
== DIE_INIT_MONARCH_LEAVE
)
181 ia64_mca_printk(KERN_NOTICE
182 "%s: kdump not configured\n",
187 if (val
!= DIE_INIT_MONARCH_LEAVE
&&
188 val
!= DIE_INIT_MONARCH_PROCESS
&&
189 val
!= DIE_MCA_MONARCH_LEAVE
)
192 nd
= (struct ia64_mca_notify_die
*)args
->err
;
195 case DIE_INIT_MONARCH_PROCESS
:
196 /* Reason code 1 means machine check rendezvous*/
197 if (kdump_on_init
&& (nd
->sos
->rv_rc
!= 1)) {
198 if (atomic_inc_return(&kdump_in_progress
) != 1)
199 kdump_freeze_monarch
= 1;
202 case DIE_INIT_MONARCH_LEAVE
:
203 /* Reason code 1 means machine check rendezvous*/
204 if (kdump_on_init
&& (nd
->sos
->rv_rc
!= 1))
205 machine_kdump_on_init();
207 case DIE_MCA_MONARCH_LEAVE
:
208 /* *(nd->data) indicate if MCA is recoverable */
209 if (kdump_on_fatal_mca
&& !(*(nd
->data
))) {
210 if (atomic_inc_return(&kdump_in_progress
) == 1)
211 machine_kdump_on_init();
212 /* We got fatal MCA while kdump!? No way!! */
220 static struct ctl_table kdump_ctl_table
[] = {
222 .procname
= "kdump_on_init",
223 .data
= &kdump_on_init
,
224 .maxlen
= sizeof(int),
226 .proc_handler
= proc_dointvec
,
229 .procname
= "kdump_on_fatal_mca",
230 .data
= &kdump_on_fatal_mca
,
231 .maxlen
= sizeof(int),
233 .proc_handler
= proc_dointvec
,
238 static struct ctl_table sys_table
[] = {
240 .procname
= "kernel",
242 .child
= kdump_ctl_table
,
249 machine_crash_setup(void)
251 /* be notified before default_monarch_init_process */
252 static struct notifier_block kdump_init_notifier_nb
= {
253 .notifier_call
= kdump_init_notifier
,
257 if((ret
= register_die_notifier(&kdump_init_notifier_nb
)) != 0)
260 register_sysctl_table(sys_table
);
265 __initcall(machine_crash_setup
);