// SPDX-License-Identifier: GPL-2.0-only
/*
* crash.c - kernel crash support code.
* Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
*/
#include <linux/buildid.h>
#include <linux/init.h>
#include <linux/utsname.h>
#include <linux/vmalloc.h>
#include <linux/sizes.h>
#include <linux/kexec.h>
#include <linux/memory.h>
#include <linux/cpuhotplug.h>
#include <linux/memblock.h>
#include <linux/kmemleak.h>
#include <asm/page.h>
#include <asm/sections.h>
#include <crypto/sha1.h>
#include "kallsyms_internal.h"
#include "kexec_internal.h"
/* vmcoreinfo stuff */
unsigned char *vmcoreinfo_data;
size_t vmcoreinfo_size;
u32 *vmcoreinfo_note;
/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
static unsigned char *vmcoreinfo_data_safecopy;
Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
void *data, size_t data_len)
{
struct elf_note *note = (struct elf_note *)buf;
note->n_namesz = strlen(name) + 1;
note->n_descsz = data_len;
note->n_type = type;
buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word));
memcpy(buf, name, note->n_namesz);
buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word));
memcpy(buf, data, data_len);
buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word));
return buf;
}
void final_note(Elf_Word *buf)
{
memset(buf, 0, sizeof(struct elf_note));
}
static void update_vmcoreinfo_note(void)
{
u32 *buf = vmcoreinfo_note;
if (!vmcoreinfo_size)
return;
buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
vmcoreinfo_size);
final_note(buf);
}
void crash_update_vmcoreinfo_safecopy(void *ptr)
{
if (ptr)
memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size);
vmcoreinfo_data_safecopy = ptr;
}
void crash_save_vmcoreinfo(void)
{
if (!vmcoreinfo_note)
return;
/* Use the safe copy to generate vmcoreinfo note if have */
if (vmcoreinfo_data_safecopy)
vmcoreinfo_data = vmcoreinfo_data_safecopy;
vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
update_vmcoreinfo_note();
}
void vmcoreinfo_append_str(const char *fmt, ...)
{
va_list args;
char buf[0x50];
size_t r;
va_start(args, fmt);
r = vscnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
vmcoreinfo_size += r;
WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES,
"vmcoreinfo data exceeds allocated size, truncating");
}
/*
* provide an empty default implementation here -- architecture
* code may override this
*/
void __weak arch_crash_save_vmcoreinfo(void)
{}
phys_addr_t __weak paddr_vmcoreinfo_note(void)
{
return __pa(vmcoreinfo_note);
}
EXPORT_SYMBOL(paddr_vmcoreinfo_note);
static int __init crash_save_vmcoreinfo_init(void)
{
vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL);
if (!vmcoreinfo_data) {
pr_warn("Memory allocation for vmcoreinfo_data failed\n");
return -ENOMEM;
}
vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE,
GFP_KERNEL | __GFP_ZERO);
if (!vmcoreinfo_note) {
free_page((unsigned long)vmcoreinfo_data);
vmcoreinfo_data = NULL;
pr_warn("Memory allocation for vmcoreinfo_note failed\n");
return -ENOMEM;
}
VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
VMCOREINFO_BUILD_ID();
VMCOREINFO_PAGESIZE(PAGE_SIZE);
VMCOREINFO_SYMBOL(init_uts_ns);
VMCOREINFO_OFFSET(uts_namespace, name);
VMCOREINFO_SYMBOL(node_online_map);
#ifdef CONFIG_MMU
VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
#endif
VMCOREINFO_SYMBOL(_stext);
vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", (unsigned long) VMALLOC_START);
#ifndef CONFIG_NUMA
VMCOREINFO_SYMBOL(mem_map);
VMCOREINFO_SYMBOL(contig_page_data);
#endif
#ifdef CONFIG_SPARSEMEM
VMCOREINFO_SYMBOL_ARRAY(mem_section);
VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
VMCOREINFO_STRUCT_SIZE(mem_section);
VMCOREINFO_OFFSET(mem_section, section_mem_map);
VMCOREINFO_NUMBER(SECTION_SIZE_BITS);
VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS);
#endif
VMCOREINFO_STRUCT_SIZE(page);
VMCOREINFO_STRUCT_SIZE(pglist_data);
VMCOREINFO_STRUCT_SIZE(zone);
VMCOREINFO_STRUCT_SIZE(free_area);
VMCOREINFO_STRUCT_SIZE(list_head);
VMCOREINFO_SIZE(nodemask_t);
VMCOREINFO_OFFSET(page, flags);
VMCOREINFO_OFFSET(page, _refcount);
VMCOREINFO_OFFSET(page, mapping);
VMCOREINFO_OFFSET(page, lru);
VMCOREINFO_OFFSET(page, _mapcount);
VMCOREINFO_OFFSET(page, private);
VMCOREINFO_OFFSET(page, compound_head);
VMCOREINFO_OFFSET(pglist_data, node_zones);
VMCOREINFO_OFFSET(pglist_data, nr_zones);
#ifdef CONFIG_FLATMEM
VMCOREINFO_OFFSET(pglist_data, node_mem_map);
#endif
VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
VMCOREINFO_OFFSET(pglist_data, node_id);
VMCOREINFO_OFFSET(zone, free_area);
VMCOREINFO_OFFSET(zone, vm_stat);
VMCOREINFO_OFFSET(zone, spanned_pages);
VMCOREINFO_OFFSET(free_area, free_list);
VMCOREINFO_OFFSET(list_head, next);
VMCOREINFO_OFFSET(list_head, prev);
VMCOREINFO_LENGTH(zone.free_area, NR_PAGE_ORDERS);
log_buf_vmcoreinfo_setup();
VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
VMCOREINFO_NUMBER(NR_FREE_PAGES);
VMCOREINFO_NUMBER(PG_lru);
VMCOREINFO_NUMBER(PG_private);
VMCOREINFO_NUMBER(PG_swapcache);
VMCOREINFO_NUMBER(PG_swapbacked);
VMCOREINFO_NUMBER(PG_slab);
#ifdef CONFIG_MEMORY_FAILURE
VMCOREINFO_NUMBER(PG_hwpoison);
#endif
VMCOREINFO_NUMBER(PG_head_mask);
#define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy)
VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
#ifdef CONFIG_HUGETLB_PAGE
VMCOREINFO_NUMBER(PG_hugetlb);
#define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline)
VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);
#endif
#ifdef CONFIG_KALLSYMS
VMCOREINFO_SYMBOL(kallsyms_names);
VMCOREINFO_SYMBOL(kallsyms_num_syms);
VMCOREINFO_SYMBOL(kallsyms_token_table);
VMCOREINFO_SYMBOL(kallsyms_token_index);
#ifdef CONFIG_KALLSYMS_BASE_RELATIVE
VMCOREINFO_SYMBOL(kallsyms_offsets);
VMCOREINFO_SYMBOL(kallsyms_relative_base);
#else
VMCOREINFO_SYMBOL(kallsyms_addresses);
#endif /* CONFIG_KALLSYMS_BASE_RELATIVE */
#endif /* CONFIG_KALLSYMS */
arch_crash_save_vmcoreinfo();
update_vmcoreinfo_note();
return 0;
}
subsys_initcall(crash_save_vmcoreinfo_init);
