projects / linux-block.git / blame
| 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> | |
| 6 | #include <linux/bootmem.h> | |
| 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 | ||
| 39 | local_irq_disable(); | |
| 8dd92891 | 40 | if (!cpumask_test_cpu(cpu, &cpus_in_crash)) |
| 7aa1c8f4 | 41 | crash_save_cpu(regs, cpu); |
| 8dd92891 | 42 | cpumask_set_cpu(cpu, &cpus_in_crash); |
| 7aa1c8f4 RB |
43 | |
| 44 | while (!atomic_read(&kexec_ready_to_reboot)) | |
| 45 | cpu_relax(); | |
| 46 | relocated_kexec_smp_wait(NULL); | |
| 47 | /* NOTREACHED */ | |
| 48 | } | |
| 49 | ||
| 50 | static void crash_kexec_prepare_cpus(void) | |
| 51 | { | |
| 54c721b8 | 52 | static int cpus_stopped; |
| 7aa1c8f4 | 53 | unsigned int msecs; |
| 54c721b8 | 54 | unsigned int ncpus; |
| 7aa1c8f4 | 55 | |
| 54c721b8 HK |
56 | if (cpus_stopped) |
| 57 | return; | |
| 58 | ||
| 59 | ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ | |
| 7aa1c8f4 | 60 | |
| c83c2eed | 61 | smp_call_function(crash_shutdown_secondary, NULL, 0); |
| 7aa1c8f4 RB |
62 | smp_wmb(); |
| 63 | ||
| 64 | /* | |
| 65 | * The crash CPU sends an IPI and wait for other CPUs to | |
| 66 | * respond. Delay of at least 10 seconds. | |
| 67 | */ | |
| 68 | pr_emerg("Sending IPI to other cpus...\n"); | |
| 69 | msecs = 10000; | |
| 8dd92891 | 70 | while ((cpumask_weight(&cpus_in_crash) < ncpus) && (--msecs > 0)) { |
| 7aa1c8f4 RB |
71 | cpu_relax(); |
| 72 | mdelay(1); | |
| 73 | } | |
| 54c721b8 HK |
74 | |
| 75 | cpus_stopped = 1; | |
| 76 | } | |
| 77 | ||
| 78 | /* Override the weak function in kernel/panic.c */ | |
| 79 | void crash_smp_send_stop(void) | |
| 80 | { | |
| 81 | if (_crash_smp_send_stop) | |
| 82 | _crash_smp_send_stop(); | |
| 83 | ||
| 84 | crash_kexec_prepare_cpus(); | |
| 7aa1c8f4 RB |
85 | } |
| 86 | ||
| 87 | #else /* !defined(CONFIG_SMP) */ | |
| 88 | static void crash_kexec_prepare_cpus(void) {} | |
| 70342287 | 89 | #endif /* !defined(CONFIG_SMP) */ |
| 7aa1c8f4 RB |
90 | |
| 91 | void default_machine_crash_shutdown(struct pt_regs *regs) | |
| 92 | { | |
| 93 | local_irq_disable(); | |
| 94 | crashing_cpu = smp_processor_id(); | |
| 95 | crash_save_cpu(regs, crashing_cpu); | |
| 96 | crash_kexec_prepare_cpus(); | |
| 8dd92891 | 97 | cpumask_set_cpu(crashing_cpu, &cpus_in_crash); |
| 7aa1c8f4 | 98 | } |