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
append_elf_note(Elf_Word * buf,char * name,unsigned int type,void * data,size_t data_len)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
final_note(Elf_Word * buf)58 void final_note(Elf_Word *buf)
59 {
60 memset(buf, 0, sizeof(struct elf_note));
61 }
62
update_vmcoreinfo_note(void)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
crash_update_vmcoreinfo_safecopy(void * ptr)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
crash_save_vmcoreinfo(void)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
vmcoreinfo_append_str(const char * fmt,...)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 */
arch_crash_save_vmcoreinfo(void)119 void __weak arch_crash_save_vmcoreinfo(void)
120 {}
121
paddr_vmcoreinfo_note(void)122 phys_addr_t __weak paddr_vmcoreinfo_note(void)
123 {
124 return __pa(vmcoreinfo_note);
125 }
126 EXPORT_SYMBOL(paddr_vmcoreinfo_note);
127
hwerr_log_error_type(enum hwerr_error_type src)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
crash_save_vmcoreinfo_init(void)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