// 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 "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; struct hwerr_info {	atomic_t count;	time64_t timestamp;}; /* * The hwerr_data[] array is declared with global scope so that it remains * accessible to vmcoreinfo even when Link Time Optimization (LTO) is enabled. */struct hwerr_info hwerr_data[HWERR_RECOV_MAX]; 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); void hwerr_log_error_type(enum hwerr_error_type src){	if (src < 0 || src >= HWERR_RECOV_MAX)		return; 	atomic_inc(&hwerr_data[src].count);	WRITE_ONCE(hwerr_data[src].timestamp, ktime_get_real_seconds());}EXPORT_SYMBOL_GPL(hwerr_log_error_type); static int __init crash_save_vmcoreinfo_init(void){	int order;	order = get_order(VMCOREINFO_BYTES);	vmcoreinfo_data = (unsigned char *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order);	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_pages((unsigned long)vmcoreinfo_data, order);		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_VMEMMAP	VMCOREINFO_SYMBOL_ARRAY(vmemmap);#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_info);	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);#define PAGE_SLAB_MAPCOUNT_VALUE	(PGTY_slab << 24)	VMCOREINFO_NUMBER(PAGE_SLAB_MAPCOUNT_VALUE);#ifdef CONFIG_MEMORY_FAILURE	VMCOREINFO_NUMBER(PG_hwpoison);#endif	VMCOREINFO_NUMBER(PG_head_mask);#define PAGE_BUDDY_MAPCOUNT_VALUE	(PGTY_buddy << 24)	VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);#define PAGE_HUGETLB_MAPCOUNT_VALUE	(PGTY_hugetlb << 24)	VMCOREINFO_NUMBER(PAGE_HUGETLB_MAPCOUNT_VALUE);#define PAGE_OFFLINE_MAPCOUNT_VALUE	(PGTY_offline << 24)	VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);#ifdef CONFIG_UNACCEPTED_MEMORY#define PAGE_UNACCEPTED_MAPCOUNT_VALUE	(PGTY_unaccepted << 24)	VMCOREINFO_NUMBER(PAGE_UNACCEPTED_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);	VMCOREINFO_SYMBOL(kallsyms_offsets);#endif /* CONFIG_KALLSYMS */ 	arch_crash_save_vmcoreinfo();	update_vmcoreinfo_note(); 	return 0;} subsys_initcall(crash_save_vmcoreinfo_init);