// SPDX-License-Identifier: GPL-2.0-only/* * crash.c - kernel crash support code. * Copyright (C) 2002-2004 Eric Biederman  <ebiederm@xmission.com> */ #include <linux/crash_core.h>#include <linux/utsname.h>#include <linux/vmalloc.h> #include <asm/page.h>#include <asm/sections.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; /* * parsing the "crashkernel" commandline * * this code is intended to be called from architecture specific code */  /* * This function parses command lines in the format * *   crashkernel=ramsize-range:size[,...][@offset] * * The function returns 0 on success and -EINVAL on failure. */static int __init parse_crashkernel_mem(char *cmdline,					unsigned long long system_ram,					unsigned long long *crash_size,					unsigned long long *crash_base){	char *cur = cmdline, *tmp; 	/* for each entry of the comma-separated list */	do {		unsigned long long start, end = ULLONG_MAX, size; 		/* get the start of the range */		start = memparse(cur, &tmp);		if (cur == tmp) {			pr_warn("crashkernel: Memory value expected\n");			return -EINVAL;		}		cur = tmp;		if (*cur != '-') {			pr_warn("crashkernel: '-' expected\n");			return -EINVAL;		}		cur++; 		/* if no ':' is here, than we read the end */		if (*cur != ':') {			end = memparse(cur, &tmp);			if (cur == tmp) {				pr_warn("crashkernel: Memory value expected\n");				return -EINVAL;			}			cur = tmp;			if (end <= start) {				pr_warn("crashkernel: end <= start\n");				return -EINVAL;			}		} 		if (*cur != ':') {			pr_warn("crashkernel: ':' expected\n");			return -EINVAL;		}		cur++; 		size = memparse(cur, &tmp);		if (cur == tmp) {			pr_warn("Memory value expected\n");			return -EINVAL;		}		cur = tmp;		if (size >= system_ram) {			pr_warn("crashkernel: invalid size\n");			return -EINVAL;		} 		/* match ? */		if (system_ram >= start && system_ram < end) {			*crash_size = size;			break;		}	} while (*cur++ == ','); 	if (*crash_size > 0) {		while (*cur && *cur != ' ' && *cur != '@')			cur++;		if (*cur == '@') {			cur++;			*crash_base = memparse(cur, &tmp);			if (cur == tmp) {				pr_warn("Memory value expected after '@'\n");				return -EINVAL;			}		}	} else		pr_info("crashkernel size resulted in zero bytes\n"); 	return 0;} /* * That function parses "simple" (old) crashkernel command lines like * *	crashkernel=size[@offset] * * It returns 0 on success and -EINVAL on failure. */static int __init parse_crashkernel_simple(char *cmdline,					   unsigned long long *crash_size,					   unsigned long long *crash_base){	char *cur = cmdline; 	*crash_size = memparse(cmdline, &cur);	if (cmdline == cur) {		pr_warn("crashkernel: memory value expected\n");		return -EINVAL;	} 	if (*cur == '@')		*crash_base = memparse(cur+1, &cur);	else if (*cur != ' ' && *cur != '\0') {		pr_warn("crashkernel: unrecognized char: %c\n", *cur);		return -EINVAL;	} 	return 0;} #define SUFFIX_HIGH 0#define SUFFIX_LOW  1#define SUFFIX_NULL 2static __initdata char *suffix_tbl[] = {	[SUFFIX_HIGH] = ",high",	[SUFFIX_LOW]  = ",low",	[SUFFIX_NULL] = NULL,}; /* * That function parses "suffix"  crashkernel command lines like * *	crashkernel=size,[high|low] * * It returns 0 on success and -EINVAL on failure. */static int __init parse_crashkernel_suffix(char *cmdline,					   unsigned long long	*crash_size,					   const char *suffix){	char *cur = cmdline; 	*crash_size = memparse(cmdline, &cur);	if (cmdline == cur) {		pr_warn("crashkernel: memory value expected\n");		return -EINVAL;	} 	/* check with suffix */	if (strncmp(cur, suffix, strlen(suffix))) {		pr_warn("crashkernel: unrecognized char: %c\n", *cur);		return -EINVAL;	}	cur += strlen(suffix);	if (*cur != ' ' && *cur != '\0') {		pr_warn("crashkernel: unrecognized char: %c\n", *cur);		return -EINVAL;	} 	return 0;} static __init char *get_last_crashkernel(char *cmdline,			     const char *name,			     const char *suffix){	char *p = cmdline, *ck_cmdline = NULL; 	/* find crashkernel and use the last one if there are more */	p = strstr(p, name);	while (p) {		char *end_p = strchr(p, ' ');		char *q; 		if (!end_p)			end_p = p + strlen(p); 		if (!suffix) {			int i; 			/* skip the one with any known suffix */			for (i = 0; suffix_tbl[i]; i++) {				q = end_p - strlen(suffix_tbl[i]);				if (!strncmp(q, suffix_tbl[i],					     strlen(suffix_tbl[i])))					goto next;			}			ck_cmdline = p;		} else {			q = end_p - strlen(suffix);			if (!strncmp(q, suffix, strlen(suffix)))				ck_cmdline = p;		}next:		p = strstr(p+1, name);	} 	if (!ck_cmdline)		return NULL; 	return ck_cmdline;} static int __init __parse_crashkernel(char *cmdline,			     unsigned long long system_ram,			     unsigned long long *crash_size,			     unsigned long long *crash_base,			     const char *name,			     const char *suffix){	char	*first_colon, *first_space;	char	*ck_cmdline; 	BUG_ON(!crash_size || !crash_base);	*crash_size = 0;	*crash_base = 0; 	ck_cmdline = get_last_crashkernel(cmdline, name, suffix); 	if (!ck_cmdline)		return -EINVAL; 	ck_cmdline += strlen(name); 	if (suffix)		return parse_crashkernel_suffix(ck_cmdline, crash_size,				suffix);	/*	 * if the commandline contains a ':', then that's the extended	 * syntax -- if not, it must be the classic syntax	 */	first_colon = strchr(ck_cmdline, ':');	first_space = strchr(ck_cmdline, ' ');	if (first_colon && (!first_space || first_colon < first_space))		return parse_crashkernel_mem(ck_cmdline, system_ram,				crash_size, crash_base); 	return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);} /* * That function is the entry point for command line parsing and should be * called from the arch-specific code. */int __init parse_crashkernel(char *cmdline,			     unsigned long long system_ram,			     unsigned long long *crash_size,			     unsigned long long *crash_base){	return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,					"crashkernel=", NULL);} int __init parse_crashkernel_high(char *cmdline,			     unsigned long long system_ram,			     unsigned long long *crash_size,			     unsigned long long *crash_base){	return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,				"crashkernel=", suffix_tbl[SUFFIX_HIGH]);} int __init parse_crashkernel_low(char *cmdline,			     unsigned long long system_ram,			     unsigned long long *crash_size,			     unsigned long long *crash_base){	return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,				"crashkernel=", suffix_tbl[SUFFIX_LOW]);} 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;} /* * 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_PAGESIZE(PAGE_SIZE); 	VMCOREINFO_SYMBOL(init_uts_ns);	VMCOREINFO_SYMBOL(node_online_map);#ifdef CONFIG_MMU	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);#endif	VMCOREINFO_SYMBOL(_stext);	VMCOREINFO_SYMBOL(vmap_area_list); #ifndef CONFIG_NEED_MULTIPLE_NODES	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);#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_dtor);	VMCOREINFO_OFFSET(page, compound_order);	VMCOREINFO_OFFSET(page, compound_head);	VMCOREINFO_OFFSET(pglist_data, node_zones);	VMCOREINFO_OFFSET(pglist_data, nr_zones);#ifdef CONFIG_FLAT_NODE_MEM_MAP	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_OFFSET(vmap_area, va_start);	VMCOREINFO_OFFSET(vmap_area, list);	VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);	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(HUGETLB_PAGE_DTOR);#define PAGE_OFFLINE_MAPCOUNT_VALUE	(~PG_offline)	VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);#endif 	arch_crash_save_vmcoreinfo();	update_vmcoreinfo_note(); 	return 0;} subsys_initcall(crash_save_vmcoreinfo_init);