1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * crash.c - kernel crash support code. 4 * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com> 5 */ 6 7 #include <linux/buildid.h> 8 #include <linux/init.h> 9 #include <linux/utsname.h> 10 #include <linux/vmalloc.h> 11 #include <linux/sizes.h> 12 #include <linux/kexec.h> 13 #include <linux/memory.h> 14 #include <linux/cpuhotplug.h> 15 #include <linux/memblock.h> 16 #include <linux/kmemleak.h> 17 18 #include <asm/page.h> 19 #include <asm/sections.h> 20 21 #include <crypto/sha1.h> 22 23 #include "kallsyms_internal.h" 24 #include "kexec_internal.h" 25 26 /* vmcoreinfo stuff */ 27 unsigned char *vmcoreinfo_data; 28 size_t vmcoreinfo_size; 29 u32 *vmcoreinfo_note; 30 31 /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */ 32 static unsigned char *vmcoreinfo_data_safecopy; 33 34 struct hwerr_info { 35 atomic_t count; 36 time64_t timestamp; 37 }; 38 39 static struct hwerr_info hwerr_data[HWERR_RECOV_MAX]; 40 41 Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, 42 void *data, size_t data_len) 43 { 44 struct elf_note *note = (struct elf_note *)buf; 45 46 note->n_namesz = strlen(name) + 1; 47 note->n_descsz = data_len; 48 note->n_type = type; 49 buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word)); 50 memcpy(buf, name, note->n_namesz); 51 buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word)); 52 memcpy(buf, data, data_len); 53 buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word)); 54 55 return buf; 56 } 57 58 void final_note(Elf_Word *buf) 59 { 60 memset(buf, 0, sizeof(struct elf_note)); 61 } 62 63 static void update_vmcoreinfo_note(void) 64 { 65 u32 *buf = vmcoreinfo_note; 66 67 if (!vmcoreinfo_size) 68 return; 69 buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, 70 vmcoreinfo_size); 71 final_note(buf); 72 } 73 74 void crash_update_vmcoreinfo_safecopy(void *ptr) 75 { 76 if (ptr) 77 memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size); 78 79 vmcoreinfo_data_safecopy = ptr; 80 } 81 82 void crash_save_vmcoreinfo(void) 83 { 84 if (!vmcoreinfo_note) 85 return; 86 87 /* Use the safe copy to generate vmcoreinfo note if have */ 88 if (vmcoreinfo_data_safecopy) 89 vmcoreinfo_data = vmcoreinfo_data_safecopy; 90 91 vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds()); 92 update_vmcoreinfo_note(); 93 } 94 95 void vmcoreinfo_append_str(const char *fmt, ...) 96 { 97 va_list args; 98 char buf[0x50]; 99 size_t r; 100 101 va_start(args, fmt); 102 r = vscnprintf(buf, sizeof(buf), fmt, args); 103 va_end(args); 104 105 r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size); 106 107 memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r); 108 109 vmcoreinfo_size += r; 110 111 WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES, 112 "vmcoreinfo data exceeds allocated size, truncating"); 113 } 114 115 /* 116 * provide an empty default implementation here -- architecture 117 * code may override this 118 */ 119 void __weak arch_crash_save_vmcoreinfo(void) 120 {} 121 122 phys_addr_t __weak paddr_vmcoreinfo_note(void) 123 { 124 return __pa(vmcoreinfo_note); 125 } 126 EXPORT_SYMBOL(paddr_vmcoreinfo_note); 127 128 void hwerr_log_error_type(enum hwerr_error_type src) 129 { 130 if (src < 0 || src >= HWERR_RECOV_MAX) 131 return; 132 133 atomic_inc(&hwerr_data[src].count); 134 WRITE_ONCE(hwerr_data[src].timestamp, ktime_get_real_seconds()); 135 } 136 EXPORT_SYMBOL_GPL(hwerr_log_error_type); 137 138 static int __init crash_save_vmcoreinfo_init(void) 139 { 140 vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL); 141 if (!vmcoreinfo_data) { 142 pr_warn("Memory allocation for vmcoreinfo_data failed\n"); 143 return -ENOMEM; 144 } 145 146 vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE, 147 GFP_KERNEL | __GFP_ZERO); 148 if (!vmcoreinfo_note) { 149 free_page((unsigned long)vmcoreinfo_data); 150 vmcoreinfo_data = NULL; 151 pr_warn("Memory allocation for vmcoreinfo_note failed\n"); 152 return -ENOMEM; 153 } 154 155 VMCOREINFO_OSRELEASE(init_uts_ns.name.release); 156 VMCOREINFO_BUILD_ID(); 157 VMCOREINFO_PAGESIZE(PAGE_SIZE); 158 159 VMCOREINFO_SYMBOL(init_uts_ns); 160 VMCOREINFO_OFFSET(uts_namespace, name); 161 VMCOREINFO_SYMBOL(node_online_map); 162 #ifdef CONFIG_MMU 163 VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir); 164 #endif 165 VMCOREINFO_SYMBOL(_stext); 166 vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", (unsigned long) VMALLOC_START); 167 168 #ifndef CONFIG_NUMA 169 VMCOREINFO_SYMBOL(mem_map); 170 VMCOREINFO_SYMBOL(contig_page_data); 171 #endif 172 #ifdef CONFIG_SPARSEMEM_VMEMMAP 173 VMCOREINFO_SYMBOL_ARRAY(vmemmap); 174 #endif 175 #ifdef CONFIG_SPARSEMEM 176 VMCOREINFO_SYMBOL_ARRAY(mem_section); 177 VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS); 178 VMCOREINFO_STRUCT_SIZE(mem_section); 179 VMCOREINFO_OFFSET(mem_section, section_mem_map); 180 VMCOREINFO_NUMBER(SECTION_SIZE_BITS); 181 VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS); 182 #endif 183 VMCOREINFO_STRUCT_SIZE(page); 184 VMCOREINFO_STRUCT_SIZE(pglist_data); 185 VMCOREINFO_STRUCT_SIZE(zone); 186 VMCOREINFO_STRUCT_SIZE(free_area); 187 VMCOREINFO_STRUCT_SIZE(list_head); 188 VMCOREINFO_SIZE(nodemask_t); 189 VMCOREINFO_OFFSET(page, flags); 190 VMCOREINFO_OFFSET(page, _refcount); 191 VMCOREINFO_OFFSET(page, mapping); 192 VMCOREINFO_OFFSET(page, lru); 193 VMCOREINFO_OFFSET(page, _mapcount); 194 VMCOREINFO_OFFSET(page, private); 195 VMCOREINFO_OFFSET(page, compound_head); 196 VMCOREINFO_OFFSET(pglist_data, node_zones); 197 VMCOREINFO_OFFSET(pglist_data, nr_zones); 198 #ifdef CONFIG_FLATMEM 199 VMCOREINFO_OFFSET(pglist_data, node_mem_map); 200 #endif 201 VMCOREINFO_OFFSET(pglist_data, node_start_pfn); 202 VMCOREINFO_OFFSET(pglist_data, node_spanned_pages); 203 VMCOREINFO_OFFSET(pglist_data, node_id); 204 VMCOREINFO_OFFSET(zone, free_area); 205 VMCOREINFO_OFFSET(zone, vm_stat); 206 VMCOREINFO_OFFSET(zone, spanned_pages); 207 VMCOREINFO_OFFSET(free_area, free_list); 208 VMCOREINFO_OFFSET(list_head, next); 209 VMCOREINFO_OFFSET(list_head, prev); 210 VMCOREINFO_LENGTH(zone.free_area, NR_PAGE_ORDERS); 211 log_buf_vmcoreinfo_setup(); 212 VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); 213 VMCOREINFO_NUMBER(NR_FREE_PAGES); 214 VMCOREINFO_NUMBER(PG_lru); 215 VMCOREINFO_NUMBER(PG_private); 216 VMCOREINFO_NUMBER(PG_swapcache); 217 VMCOREINFO_NUMBER(PG_swapbacked); 218 #define PAGE_SLAB_MAPCOUNT_VALUE (PGTY_slab << 24) 219 VMCOREINFO_NUMBER(PAGE_SLAB_MAPCOUNT_VALUE); 220 #ifdef CONFIG_MEMORY_FAILURE 221 VMCOREINFO_NUMBER(PG_hwpoison); 222 #endif 223 VMCOREINFO_NUMBER(PG_head_mask); 224 #define PAGE_BUDDY_MAPCOUNT_VALUE (PGTY_buddy << 24) 225 VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE); 226 #define PAGE_HUGETLB_MAPCOUNT_VALUE (PGTY_hugetlb << 24) 227 VMCOREINFO_NUMBER(PAGE_HUGETLB_MAPCOUNT_VALUE); 228 #define PAGE_OFFLINE_MAPCOUNT_VALUE (PGTY_offline << 24) 229 VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE); 230 #ifdef CONFIG_UNACCEPTED_MEMORY 231 #define PAGE_UNACCEPTED_MAPCOUNT_VALUE (PGTY_unaccepted << 24) 232 VMCOREINFO_NUMBER(PAGE_UNACCEPTED_MAPCOUNT_VALUE); 233 #endif 234 235 #ifdef CONFIG_KALLSYMS 236 VMCOREINFO_SYMBOL(kallsyms_names); 237 VMCOREINFO_SYMBOL(kallsyms_num_syms); 238 VMCOREINFO_SYMBOL(kallsyms_token_table); 239 VMCOREINFO_SYMBOL(kallsyms_token_index); 240 VMCOREINFO_SYMBOL(kallsyms_offsets); 241 VMCOREINFO_SYMBOL(kallsyms_relative_base); 242 #endif /* CONFIG_KALLSYMS */ 243 244 arch_crash_save_vmcoreinfo(); 245 update_vmcoreinfo_note(); 246 247 return 0; 248 } 249 250 subsys_initcall(crash_save_vmcoreinfo_init); 251