linux/arch/x86/kernel/crash.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Architecture specific (i386/x86_64) functions for kexec based crash dumps.
 *
 * Created by: Hariprasad Nellitheertha ([email protected])
 *
 * Copyright (C) IBM Corporation, 2004. All rights reserved.
 * Copyright (C) Red Hat Inc., 2014. All rights reserved.
 * Authors:
 *      Vivek Goyal <[email protected]>
 *
 */

#define pr_fmt(fmt) …

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/memblock.h>

#include <asm/bootparam.h>
#include <asm/processor.h>
#include <asm/hardirq.h>
#include <asm/nmi.h>
#include <asm/hw_irq.h>
#include <asm/apic.h>
#include <asm/e820/types.h>
#include <asm/io_apic.h>
#include <asm/hpet.h>
#include <linux/kdebug.h>
#include <asm/cpu.h>
#include <asm/reboot.h>
#include <asm/intel_pt.h>
#include <asm/crash.h>
#include <asm/cmdline.h>
#include <asm/sev.h>

/* Used while preparing memory map entries for second kernel */
struct crash_memmap_data { … };

#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)

static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
{ … }

void kdump_nmi_shootdown_cpus(void)
{ … }

/* Override the weak function in kernel/panic.c */
void crash_smp_send_stop(void)
{ … }

#else
void crash_smp_send_stop(void)
{
	/* There are no cpus to shootdown */
}
#endif

void native_machine_crash_shutdown(struct pt_regs *regs)
{ … }

#if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_HOTPLUG)
static int get_nr_ram_ranges_callback(struct resource *res, void *arg)
{ … }

/* Gather all the required information to prepare elf headers for ram regions */
static struct crash_mem *fill_up_crash_elf_data(void)
{ … }

/*
 * Look for any unwanted ranges between mstart, mend and remove them. This
 * might lead to split and split ranges are put in cmem->ranges[] array
 */
static int elf_header_exclude_ranges(struct crash_mem *cmem)
{ … }

static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)
{ … }

/* Prepare elf headers. Return addr and size */
static int prepare_elf_headers(void **addr, unsigned long *sz,
			       unsigned long *nr_mem_ranges)
{ … }
#endif

#ifdef CONFIG_KEXEC_FILE
static int add_e820_entry(struct boot_params *params, struct e820_entry *entry)
{ … }

static int memmap_entry_callback(struct resource *res, void *arg)
{ … }

static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem,
				 unsigned long long mstart,
				 unsigned long long mend)
{ … }

/* Prepare memory map for crash dump kernel */
int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
{ … }

int crash_load_segments(struct kimage *image)
{ … }
#endif /* CONFIG_KEXEC_FILE */

#ifdef CONFIG_CRASH_HOTPLUG

#undef pr_fmt
#define pr_fmt(fmt) …

int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags)
{ … }

unsigned int arch_crash_get_elfcorehdr_size(void)
{ … }

/**
 * arch_crash_handle_hotplug_event() - Handle hotplug elfcorehdr changes
 * @image: a pointer to kexec_crash_image
 * @arg: struct memory_notify handler for memory hotplug case and
 *       NULL for CPU hotplug case.
 *
 * Prepare the new elfcorehdr and replace the existing elfcorehdr.
 */
void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
{ … }
#endif