Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
7aa1c8f4 RB |
2 | #include <linux/kernel.h> |
3 | #include <linux/smp.h> | |
4 | #include <linux/reboot.h> | |
5 | #include <linux/kexec.h> | |
57c8a661 | 6 | #include <linux/memblock.h> |
7aa1c8f4 RB |
7 | #include <linux/crash_dump.h> |
8 | #include <linux/delay.h> | |
7aa1c8f4 RB |
9 | #include <linux/irq.h> |
10 | #include <linux/types.h> | |
11 | #include <linux/sched.h> | |
68db0cf1 | 12 | #include <linux/sched/task_stack.h> |
7aa1c8f4 RB |
13 | |
14 | /* This keeps a track of which one is crashing cpu. */ | |
15 | static int crashing_cpu = -1; | |
16 | static cpumask_t cpus_in_crash = CPU_MASK_NONE; | |
17 | ||
18 | #ifdef CONFIG_SMP | |
c80e1b62 | 19 | static void crash_shutdown_secondary(void *passed_regs) |
7aa1c8f4 | 20 | { |
c80e1b62 | 21 | struct pt_regs *regs = passed_regs; |
7aa1c8f4 RB |
22 | int cpu = smp_processor_id(); |
23 | ||
c80e1b62 CM |
24 | /* |
25 | * If we are passed registers, use those. Otherwise get the | |
26 | * regs from the last interrupt, which should be correct, as | |
27 | * we are in an interrupt. But if the regs are not there, | |
28 | * pull them from the top of the stack. They are probably | |
29 | * wrong, but we need something to keep from crashing again. | |
30 | */ | |
31 | if (!regs) | |
32 | regs = get_irq_regs(); | |
33 | if (!regs) | |
34 | regs = task_pt_regs(current); | |
7aa1c8f4 RB |
35 | |
36 | if (!cpu_online(cpu)) | |
37 | return; | |
38 | ||
dc57aaf9 DZ |
39 | /* We won't be sent IPIs any more. */ |
40 | set_cpu_online(cpu, false); | |
41 | ||
7aa1c8f4 | 42 | local_irq_disable(); |
8dd92891 | 43 | if (!cpumask_test_cpu(cpu, &cpus_in_crash)) |
7aa1c8f4 | 44 | crash_save_cpu(regs, cpu); |
8dd92891 | 45 | cpumask_set_cpu(cpu, &cpus_in_crash); |
7aa1c8f4 RB |
46 | |
47 | while (!atomic_read(&kexec_ready_to_reboot)) | |
48 | cpu_relax(); | |
62cac480 DZ |
49 | |
50 | kexec_reboot(); | |
51 | ||
7aa1c8f4 RB |
52 | /* NOTREACHED */ |
53 | } | |
54 | ||
55 | static void crash_kexec_prepare_cpus(void) | |
56 | { | |
54c721b8 | 57 | static int cpus_stopped; |
7aa1c8f4 | 58 | unsigned int msecs; |
54c721b8 | 59 | unsigned int ncpus; |
7aa1c8f4 | 60 | |
54c721b8 HK |
61 | if (cpus_stopped) |
62 | return; | |
63 | ||
64 | ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ | |
7aa1c8f4 | 65 | |
c83c2eed | 66 | smp_call_function(crash_shutdown_secondary, NULL, 0); |
7aa1c8f4 RB |
67 | smp_wmb(); |
68 | ||
69 | /* | |
70 | * The crash CPU sends an IPI and wait for other CPUs to | |
71 | * respond. Delay of at least 10 seconds. | |
72 | */ | |
73 | pr_emerg("Sending IPI to other cpus...\n"); | |
74 | msecs = 10000; | |
8dd92891 | 75 | while ((cpumask_weight(&cpus_in_crash) < ncpus) && (--msecs > 0)) { |
7aa1c8f4 RB |
76 | cpu_relax(); |
77 | mdelay(1); | |
78 | } | |
54c721b8 HK |
79 | |
80 | cpus_stopped = 1; | |
81 | } | |
82 | ||
83 | /* Override the weak function in kernel/panic.c */ | |
84 | void crash_smp_send_stop(void) | |
85 | { | |
86 | if (_crash_smp_send_stop) | |
87 | _crash_smp_send_stop(); | |
88 | ||
89 | crash_kexec_prepare_cpus(); | |
7aa1c8f4 RB |
90 | } |
91 | ||
92 | #else /* !defined(CONFIG_SMP) */ | |
93 | static void crash_kexec_prepare_cpus(void) {} | |
70342287 | 94 | #endif /* !defined(CONFIG_SMP) */ |
7aa1c8f4 RB |
95 | |
96 | void default_machine_crash_shutdown(struct pt_regs *regs) | |
97 | { | |
98 | local_irq_disable(); | |
99 | crashing_cpu = smp_processor_id(); | |
100 | crash_save_cpu(regs, crashing_cpu); | |
101 | crash_kexec_prepare_cpus(); | |
8dd92891 | 102 | cpumask_set_cpu(crashing_cpu, &cpus_in_crash); |
7aa1c8f4 | 103 | } |