104 строки
2.4 KiB
C
104 строки
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/kernel.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/kexec.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/crash_dump.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/types.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/task_stack.h>
|
|
|
|
/* This keeps a track of which one is crashing cpu. */
|
|
static int crashing_cpu = -1;
|
|
static cpumask_t cpus_in_crash = CPU_MASK_NONE;
|
|
|
|
#ifdef CONFIG_SMP
|
|
static void crash_shutdown_secondary(void *passed_regs)
|
|
{
|
|
struct pt_regs *regs = passed_regs;
|
|
int cpu = smp_processor_id();
|
|
|
|
/*
|
|
* If we are passed registers, use those. Otherwise get the
|
|
* regs from the last interrupt, which should be correct, as
|
|
* we are in an interrupt. But if the regs are not there,
|
|
* pull them from the top of the stack. They are probably
|
|
* wrong, but we need something to keep from crashing again.
|
|
*/
|
|
if (!regs)
|
|
regs = get_irq_regs();
|
|
if (!regs)
|
|
regs = task_pt_regs(current);
|
|
|
|
if (!cpu_online(cpu))
|
|
return;
|
|
|
|
/* We won't be sent IPIs any more. */
|
|
set_cpu_online(cpu, false);
|
|
|
|
local_irq_disable();
|
|
if (!cpumask_test_cpu(cpu, &cpus_in_crash))
|
|
crash_save_cpu(regs, cpu);
|
|
cpumask_set_cpu(cpu, &cpus_in_crash);
|
|
|
|
while (!atomic_read(&kexec_ready_to_reboot))
|
|
cpu_relax();
|
|
|
|
kexec_reboot();
|
|
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
static void crash_kexec_prepare_cpus(void)
|
|
{
|
|
static int cpus_stopped;
|
|
unsigned int msecs;
|
|
unsigned int ncpus;
|
|
|
|
if (cpus_stopped)
|
|
return;
|
|
|
|
ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */
|
|
|
|
smp_call_function(crash_shutdown_secondary, NULL, 0);
|
|
smp_wmb();
|
|
|
|
/*
|
|
* The crash CPU sends an IPI and wait for other CPUs to
|
|
* respond. Delay of at least 10 seconds.
|
|
*/
|
|
pr_emerg("Sending IPI to other cpus...\n");
|
|
msecs = 10000;
|
|
while ((cpumask_weight(&cpus_in_crash) < ncpus) && (--msecs > 0)) {
|
|
cpu_relax();
|
|
mdelay(1);
|
|
}
|
|
|
|
cpus_stopped = 1;
|
|
}
|
|
|
|
/* Override the weak function in kernel/panic.c */
|
|
void crash_smp_send_stop(void)
|
|
{
|
|
if (_crash_smp_send_stop)
|
|
_crash_smp_send_stop();
|
|
|
|
crash_kexec_prepare_cpus();
|
|
}
|
|
|
|
#else /* !defined(CONFIG_SMP) */
|
|
static void crash_kexec_prepare_cpus(void) {}
|
|
#endif /* !defined(CONFIG_SMP) */
|
|
|
|
void default_machine_crash_shutdown(struct pt_regs *regs)
|
|
{
|
|
local_irq_disable();
|
|
crashing_cpu = smp_processor_id();
|
|
crash_save_cpu(regs, crashing_cpu);
|
|
crash_kexec_prepare_cpus();
|
|
cpumask_set_cpu(crashing_cpu, &cpus_in_crash);
|
|
}
|