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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/crash_core.h>
9#include <linux/init.h>
10#include <linux/utsname.h>
11#include <linux/vmalloc.h>
12#include <linux/sizes.h>
13
14#include <asm/page.h>
15#include <asm/sections.h>
16
17#include <crypto/sha1.h>
18
19#include "kallsyms_internal.h"
20
21/* vmcoreinfo stuff */
22unsigned char *vmcoreinfo_data;
23size_t vmcoreinfo_size;
24u32 *vmcoreinfo_note;
25
26/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
27static unsigned char *vmcoreinfo_data_safecopy;
28
29/*
30 * parsing the "crashkernel" commandline
31 *
32 * this code is intended to be called from architecture specific code
33 */
34
35
36/*
37 * This function parses command lines in the format
38 *
39 * crashkernel=ramsize-range:size[,...][@offset]
40 *
41 * The function returns 0 on success and -EINVAL on failure.
42 */
43static int __init parse_crashkernel_mem(char *cmdline,
44 unsigned long long system_ram,
45 unsigned long long *crash_size,
46 unsigned long long *crash_base)
47{
48 char *cur = cmdline, *tmp;
49 unsigned long long total_mem = system_ram;
50
51 /*
52 * Firmware sometimes reserves some memory regions for its own use,
53 * so the system memory size is less than the actual physical memory
54 * size. Work around this by rounding up the total size to 128M,
55 * which is enough for most test cases.
56 */
57 total_mem = roundup(total_mem, SZ_128M);
58
59 /* for each entry of the comma-separated list */
60 do {
61 unsigned long long start, end = ULLONG_MAX, size;
62
63 /* get the start of the range */
64 start = memparse(cur, &tmp);
65 if (cur == tmp) {
66 pr_warn("crashkernel: Memory value expected\n");
67 return -EINVAL;
68 }
69 cur = tmp;
70 if (*cur != '-') {
71 pr_warn("crashkernel: '-' expected\n");
72 return -EINVAL;
73 }
74 cur++;
75
76 /* if no ':' is here, than we read the end */
77 if (*cur != ':') {
78 end = memparse(cur, &tmp);
79 if (cur == tmp) {
80 pr_warn("crashkernel: Memory value expected\n");
81 return -EINVAL;
82 }
83 cur = tmp;
84 if (end <= start) {
85 pr_warn("crashkernel: end <= start\n");
86 return -EINVAL;
87 }
88 }
89
90 if (*cur != ':') {
91 pr_warn("crashkernel: ':' expected\n");
92 return -EINVAL;
93 }
94 cur++;
95
96 size = memparse(cur, &tmp);
97 if (cur == tmp) {
98 pr_warn("Memory value expected\n");
99 return -EINVAL;
100 }
101 cur = tmp;
102 if (size >= total_mem) {
103 pr_warn("crashkernel: invalid size\n");
104 return -EINVAL;
105 }
106
107 /* match ? */
108 if (total_mem >= start && total_mem < end) {
109 *crash_size = size;
110 break;
111 }
112 } while (*cur++ == ',');
113
114 if (*crash_size > 0) {
115 while (*cur && *cur != ' ' && *cur != '@')
116 cur++;
117 if (*cur == '@') {
118 cur++;
119 *crash_base = memparse(cur, &tmp);
120 if (cur == tmp) {
121 pr_warn("Memory value expected after '@'\n");
122 return -EINVAL;
123 }
124 }
125 } else
126 pr_info("crashkernel size resulted in zero bytes\n");
127
128 return 0;
129}
130
131/*
132 * That function parses "simple" (old) crashkernel command lines like
133 *
134 * crashkernel=size[@offset]
135 *
136 * It returns 0 on success and -EINVAL on failure.
137 */
138static int __init parse_crashkernel_simple(char *cmdline,
139 unsigned long long *crash_size,
140 unsigned long long *crash_base)
141{
142 char *cur = cmdline;
143
144 *crash_size = memparse(cmdline, &cur);
145 if (cmdline == cur) {
146 pr_warn("crashkernel: memory value expected\n");
147 return -EINVAL;
148 }
149
150 if (*cur == '@')
151 *crash_base = memparse(cur+1, &cur);
152 else if (*cur != ' ' && *cur != '\0') {
153 pr_warn("crashkernel: unrecognized char: %c\n", *cur);
154 return -EINVAL;
155 }
156
157 return 0;
158}
159
160#define SUFFIX_HIGH 0
161#define SUFFIX_LOW 1
162#define SUFFIX_NULL 2
163static __initdata char *suffix_tbl[] = {
164 [SUFFIX_HIGH] = ",high",
165 [SUFFIX_LOW] = ",low",
166 [SUFFIX_NULL] = NULL,
167};
168
169/*
170 * That function parses "suffix" crashkernel command lines like
171 *
172 * crashkernel=size,[high|low]
173 *
174 * It returns 0 on success and -EINVAL on failure.
175 */
176static int __init parse_crashkernel_suffix(char *cmdline,
177 unsigned long long *crash_size,
178 const char *suffix)
179{
180 char *cur = cmdline;
181
182 *crash_size = memparse(cmdline, &cur);
183 if (cmdline == cur) {
184 pr_warn("crashkernel: memory value expected\n");
185 return -EINVAL;
186 }
187
188 /* check with suffix */
189 if (strncmp(cur, suffix, strlen(suffix))) {
190 pr_warn("crashkernel: unrecognized char: %c\n", *cur);
191 return -EINVAL;
192 }
193 cur += strlen(suffix);
194 if (*cur != ' ' && *cur != '\0') {
195 pr_warn("crashkernel: unrecognized char: %c\n", *cur);
196 return -EINVAL;
197 }
198
199 return 0;
200}
201
202static __init char *get_last_crashkernel(char *cmdline,
203 const char *name,
204 const char *suffix)
205{
206 char *p = cmdline, *ck_cmdline = NULL;
207
208 /* find crashkernel and use the last one if there are more */
209 p = strstr(p, name);
210 while (p) {
211 char *end_p = strchr(p, ' ');
212 char *q;
213
214 if (!end_p)
215 end_p = p + strlen(p);
216
217 if (!suffix) {
218 int i;
219
220 /* skip the one with any known suffix */
221 for (i = 0; suffix_tbl[i]; i++) {
222 q = end_p - strlen(suffix_tbl[i]);
223 if (!strncmp(q, suffix_tbl[i],
224 strlen(suffix_tbl[i])))
225 goto next;
226 }
227 ck_cmdline = p;
228 } else {
229 q = end_p - strlen(suffix);
230 if (!strncmp(q, suffix, strlen(suffix)))
231 ck_cmdline = p;
232 }
233next:
234 p = strstr(p+1, name);
235 }
236
237 return ck_cmdline;
238}
239
240static int __init __parse_crashkernel(char *cmdline,
241 unsigned long long system_ram,
242 unsigned long long *crash_size,
243 unsigned long long *crash_base,
244 const char *name,
245 const char *suffix)
246{
247 char *first_colon, *first_space;
248 char *ck_cmdline;
249
250 BUG_ON(!crash_size || !crash_base);
251 *crash_size = 0;
252 *crash_base = 0;
253
254 ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
255 if (!ck_cmdline)
256 return -ENOENT;
257
258 ck_cmdline += strlen(name);
259
260 if (suffix)
261 return parse_crashkernel_suffix(ck_cmdline, crash_size,
262 suffix);
263 /*
264 * if the commandline contains a ':', then that's the extended
265 * syntax -- if not, it must be the classic syntax
266 */
267 first_colon = strchr(ck_cmdline, ':');
268 first_space = strchr(ck_cmdline, ' ');
269 if (first_colon && (!first_space || first_colon < first_space))
270 return parse_crashkernel_mem(ck_cmdline, system_ram,
271 crash_size, crash_base);
272
273 return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
274}
275
276/*
277 * That function is the entry point for command line parsing and should be
278 * called from the arch-specific code.
279 */
280int __init parse_crashkernel(char *cmdline,
281 unsigned long long system_ram,
282 unsigned long long *crash_size,
283 unsigned long long *crash_base)
284{
285 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
286 "crashkernel=", NULL);
287}
288
289int __init parse_crashkernel_high(char *cmdline,
290 unsigned long long system_ram,
291 unsigned long long *crash_size,
292 unsigned long long *crash_base)
293{
294 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
295 "crashkernel=", suffix_tbl[SUFFIX_HIGH]);
296}
297
298int __init parse_crashkernel_low(char *cmdline,
299 unsigned long long system_ram,
300 unsigned long long *crash_size,
301 unsigned long long *crash_base)
302{
303 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
304 "crashkernel=", suffix_tbl[SUFFIX_LOW]);
305}
306
307/*
308 * Add a dummy early_param handler to mark crashkernel= as a known command line
309 * parameter and suppress incorrect warnings in init/main.c.
310 */
311static int __init parse_crashkernel_dummy(char *arg)
312{
313 return 0;
314}
315early_param("crashkernel", parse_crashkernel_dummy);
316
317Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
318 void *data, size_t data_len)
319{
320 struct elf_note *note = (struct elf_note *)buf;
321
322 note->n_namesz = strlen(name) + 1;
323 note->n_descsz = data_len;
324 note->n_type = type;
325 buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word));
326 memcpy(buf, name, note->n_namesz);
327 buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word));
328 memcpy(buf, data, data_len);
329 buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word));
330
331 return buf;
332}
333
334void final_note(Elf_Word *buf)
335{
336 memset(buf, 0, sizeof(struct elf_note));
337}
338
339static void update_vmcoreinfo_note(void)
340{
341 u32 *buf = vmcoreinfo_note;
342
343 if (!vmcoreinfo_size)
344 return;
345 buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
346 vmcoreinfo_size);
347 final_note(buf);
348}
349
350void crash_update_vmcoreinfo_safecopy(void *ptr)
351{
352 if (ptr)
353 memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size);
354
355 vmcoreinfo_data_safecopy = ptr;
356}
357
358void crash_save_vmcoreinfo(void)
359{
360 if (!vmcoreinfo_note)
361 return;
362
363 /* Use the safe copy to generate vmcoreinfo note if have */
364 if (vmcoreinfo_data_safecopy)
365 vmcoreinfo_data = vmcoreinfo_data_safecopy;
366
367 vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
368 update_vmcoreinfo_note();
369}
370
371void vmcoreinfo_append_str(const char *fmt, ...)
372{
373 va_list args;
374 char buf[0x50];
375 size_t r;
376
377 va_start(args, fmt);
378 r = vscnprintf(buf, sizeof(buf), fmt, args);
379 va_end(args);
380
381 r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
382
383 memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
384
385 vmcoreinfo_size += r;
386
387 WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES,
388 "vmcoreinfo data exceeds allocated size, truncating");
389}
390
391/*
392 * provide an empty default implementation here -- architecture
393 * code may override this
394 */
395void __weak arch_crash_save_vmcoreinfo(void)
396{}
397
398phys_addr_t __weak paddr_vmcoreinfo_note(void)
399{
400 return __pa(vmcoreinfo_note);
401}
402EXPORT_SYMBOL(paddr_vmcoreinfo_note);
403
404static int __init crash_save_vmcoreinfo_init(void)
405{
406 vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL);
407 if (!vmcoreinfo_data) {
408 pr_warn("Memory allocation for vmcoreinfo_data failed\n");
409 return -ENOMEM;
410 }
411
412 vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE,
413 GFP_KERNEL | __GFP_ZERO);
414 if (!vmcoreinfo_note) {
415 free_page((unsigned long)vmcoreinfo_data);
416 vmcoreinfo_data = NULL;
417 pr_warn("Memory allocation for vmcoreinfo_note failed\n");
418 return -ENOMEM;
419 }
420
421 VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
422 VMCOREINFO_BUILD_ID();
423 VMCOREINFO_PAGESIZE(PAGE_SIZE);
424
425 VMCOREINFO_SYMBOL(init_uts_ns);
426 VMCOREINFO_OFFSET(uts_namespace, name);
427 VMCOREINFO_SYMBOL(node_online_map);
428#ifdef CONFIG_MMU
429 VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
430#endif
431 VMCOREINFO_SYMBOL(_stext);
432 VMCOREINFO_SYMBOL(vmap_area_list);
433
434#ifndef CONFIG_NUMA
435 VMCOREINFO_SYMBOL(mem_map);
436 VMCOREINFO_SYMBOL(contig_page_data);
437#endif
438#ifdef CONFIG_SPARSEMEM
439 VMCOREINFO_SYMBOL_ARRAY(mem_section);
440 VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
441 VMCOREINFO_STRUCT_SIZE(mem_section);
442 VMCOREINFO_OFFSET(mem_section, section_mem_map);
443 VMCOREINFO_NUMBER(SECTION_SIZE_BITS);
444 VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS);
445#endif
446 VMCOREINFO_STRUCT_SIZE(page);
447 VMCOREINFO_STRUCT_SIZE(pglist_data);
448 VMCOREINFO_STRUCT_SIZE(zone);
449 VMCOREINFO_STRUCT_SIZE(free_area);
450 VMCOREINFO_STRUCT_SIZE(list_head);
451 VMCOREINFO_SIZE(nodemask_t);
452 VMCOREINFO_OFFSET(page, flags);
453 VMCOREINFO_OFFSET(page, _refcount);
454 VMCOREINFO_OFFSET(page, mapping);
455 VMCOREINFO_OFFSET(page, lru);
456 VMCOREINFO_OFFSET(page, _mapcount);
457 VMCOREINFO_OFFSET(page, private);
458 VMCOREINFO_OFFSET(page, compound_dtor);
459 VMCOREINFO_OFFSET(page, compound_order);
460 VMCOREINFO_OFFSET(page, compound_head);
461 VMCOREINFO_OFFSET(pglist_data, node_zones);
462 VMCOREINFO_OFFSET(pglist_data, nr_zones);
463#ifdef CONFIG_FLATMEM
464 VMCOREINFO_OFFSET(pglist_data, node_mem_map);
465#endif
466 VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
467 VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
468 VMCOREINFO_OFFSET(pglist_data, node_id);
469 VMCOREINFO_OFFSET(zone, free_area);
470 VMCOREINFO_OFFSET(zone, vm_stat);
471 VMCOREINFO_OFFSET(zone, spanned_pages);
472 VMCOREINFO_OFFSET(free_area, free_list);
473 VMCOREINFO_OFFSET(list_head, next);
474 VMCOREINFO_OFFSET(list_head, prev);
475 VMCOREINFO_OFFSET(vmap_area, va_start);
476 VMCOREINFO_OFFSET(vmap_area, list);
477 VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
478 log_buf_vmcoreinfo_setup();
479 VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
480 VMCOREINFO_NUMBER(NR_FREE_PAGES);
481 VMCOREINFO_NUMBER(PG_lru);
482 VMCOREINFO_NUMBER(PG_private);
483 VMCOREINFO_NUMBER(PG_swapcache);
484 VMCOREINFO_NUMBER(PG_swapbacked);
485 VMCOREINFO_NUMBER(PG_slab);
486#ifdef CONFIG_MEMORY_FAILURE
487 VMCOREINFO_NUMBER(PG_hwpoison);
488#endif
489 VMCOREINFO_NUMBER(PG_head_mask);
490#define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy)
491 VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
492#ifdef CONFIG_HUGETLB_PAGE
493 VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR);
494#define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline)
495 VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);
496#endif
497
498#ifdef CONFIG_KALLSYMS
499 VMCOREINFO_SYMBOL(kallsyms_names);
500 VMCOREINFO_SYMBOL(kallsyms_num_syms);
501 VMCOREINFO_SYMBOL(kallsyms_token_table);
502 VMCOREINFO_SYMBOL(kallsyms_token_index);
503#ifdef CONFIG_KALLSYMS_BASE_RELATIVE
504 VMCOREINFO_SYMBOL(kallsyms_offsets);
505 VMCOREINFO_SYMBOL(kallsyms_relative_base);
506#else
507 VMCOREINFO_SYMBOL(kallsyms_addresses);
508#endif /* CONFIG_KALLSYMS_BASE_RELATIVE */
509#endif /* CONFIG_KALLSYMS */
510
511 arch_crash_save_vmcoreinfo();
512 update_vmcoreinfo_note();
513
514 return 0;
515}
516
517subsys_initcall(crash_save_vmcoreinfo_init);