1 // SPDX-License-Identifier: GPL-2.0-only
3 * crash.c - kernel crash support code.
4 * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
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>
14 #include <asm/sections.h>
16 #include <crypto/sha1.h>
18 /* vmcoreinfo stuff */
19 unsigned char *vmcoreinfo_data
;
20 size_t vmcoreinfo_size
;
23 /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
24 static unsigned char *vmcoreinfo_data_safecopy
;
27 * parsing the "crashkernel" commandline
29 * this code is intended to be called from architecture specific code
34 * This function parses command lines in the format
36 * crashkernel=ramsize-range:size[,...][@offset]
38 * The function returns 0 on success and -EINVAL on failure.
40 static int __init
parse_crashkernel_mem(char *cmdline
,
41 unsigned long long system_ram
,
42 unsigned long long *crash_size
,
43 unsigned long long *crash_base
)
45 char *cur
= cmdline
, *tmp
;
47 /* for each entry of the comma-separated list */
49 unsigned long long start
, end
= ULLONG_MAX
, size
;
51 /* get the start of the range */
52 start
= memparse(cur
, &tmp
);
54 pr_warn("crashkernel: Memory value expected\n");
59 pr_warn("crashkernel: '-' expected\n");
64 /* if no ':' is here, than we read the end */
66 end
= memparse(cur
, &tmp
);
68 pr_warn("crashkernel: Memory value expected\n");
73 pr_warn("crashkernel: end <= start\n");
79 pr_warn("crashkernel: ':' expected\n");
84 size
= memparse(cur
, &tmp
);
86 pr_warn("Memory value expected\n");
90 if (size
>= system_ram
) {
91 pr_warn("crashkernel: invalid size\n");
96 if (system_ram
>= start
&& system_ram
< end
) {
100 } while (*cur
++ == ',');
102 if (*crash_size
> 0) {
103 while (*cur
&& *cur
!= ' ' && *cur
!= '@')
107 *crash_base
= memparse(cur
, &tmp
);
109 pr_warn("Memory value expected after '@'\n");
114 pr_info("crashkernel size resulted in zero bytes\n");
120 * That function parses "simple" (old) crashkernel command lines like
122 * crashkernel=size[@offset]
124 * It returns 0 on success and -EINVAL on failure.
126 static int __init
parse_crashkernel_simple(char *cmdline
,
127 unsigned long long *crash_size
,
128 unsigned long long *crash_base
)
132 *crash_size
= memparse(cmdline
, &cur
);
133 if (cmdline
== cur
) {
134 pr_warn("crashkernel: memory value expected\n");
139 *crash_base
= memparse(cur
+1, &cur
);
140 else if (*cur
!= ' ' && *cur
!= '\0') {
141 pr_warn("crashkernel: unrecognized char: %c\n", *cur
);
148 #define SUFFIX_HIGH 0
150 #define SUFFIX_NULL 2
151 static __initdata
char *suffix_tbl
[] = {
152 [SUFFIX_HIGH
] = ",high",
153 [SUFFIX_LOW
] = ",low",
154 [SUFFIX_NULL
] = NULL
,
158 * That function parses "suffix" crashkernel command lines like
160 * crashkernel=size,[high|low]
162 * It returns 0 on success and -EINVAL on failure.
164 static int __init
parse_crashkernel_suffix(char *cmdline
,
165 unsigned long long *crash_size
,
170 *crash_size
= memparse(cmdline
, &cur
);
171 if (cmdline
== cur
) {
172 pr_warn("crashkernel: memory value expected\n");
176 /* check with suffix */
177 if (strncmp(cur
, suffix
, strlen(suffix
))) {
178 pr_warn("crashkernel: unrecognized char: %c\n", *cur
);
181 cur
+= strlen(suffix
);
182 if (*cur
!= ' ' && *cur
!= '\0') {
183 pr_warn("crashkernel: unrecognized char: %c\n", *cur
);
190 static __init
char *get_last_crashkernel(char *cmdline
,
194 char *p
= cmdline
, *ck_cmdline
= NULL
;
196 /* find crashkernel and use the last one if there are more */
199 char *end_p
= strchr(p
, ' ');
203 end_p
= p
+ strlen(p
);
208 /* skip the one with any known suffix */
209 for (i
= 0; suffix_tbl
[i
]; i
++) {
210 q
= end_p
- strlen(suffix_tbl
[i
]);
211 if (!strncmp(q
, suffix_tbl
[i
],
212 strlen(suffix_tbl
[i
])))
217 q
= end_p
- strlen(suffix
);
218 if (!strncmp(q
, suffix
, strlen(suffix
)))
222 p
= strstr(p
+1, name
);
228 static int __init
__parse_crashkernel(char *cmdline
,
229 unsigned long long system_ram
,
230 unsigned long long *crash_size
,
231 unsigned long long *crash_base
,
235 char *first_colon
, *first_space
;
238 BUG_ON(!crash_size
|| !crash_base
);
242 ck_cmdline
= get_last_crashkernel(cmdline
, name
, suffix
);
246 ck_cmdline
+= strlen(name
);
249 return parse_crashkernel_suffix(ck_cmdline
, crash_size
,
252 * if the commandline contains a ':', then that's the extended
253 * syntax -- if not, it must be the classic syntax
255 first_colon
= strchr(ck_cmdline
, ':');
256 first_space
= strchr(ck_cmdline
, ' ');
257 if (first_colon
&& (!first_space
|| first_colon
< first_space
))
258 return parse_crashkernel_mem(ck_cmdline
, system_ram
,
259 crash_size
, crash_base
);
261 return parse_crashkernel_simple(ck_cmdline
, crash_size
, crash_base
);
265 * That function is the entry point for command line parsing and should be
266 * called from the arch-specific code.
268 int __init
parse_crashkernel(char *cmdline
,
269 unsigned long long system_ram
,
270 unsigned long long *crash_size
,
271 unsigned long long *crash_base
)
273 return __parse_crashkernel(cmdline
, system_ram
, crash_size
, crash_base
,
274 "crashkernel=", NULL
);
277 int __init
parse_crashkernel_high(char *cmdline
,
278 unsigned long long system_ram
,
279 unsigned long long *crash_size
,
280 unsigned long long *crash_base
)
282 return __parse_crashkernel(cmdline
, system_ram
, crash_size
, crash_base
,
283 "crashkernel=", suffix_tbl
[SUFFIX_HIGH
]);
286 int __init
parse_crashkernel_low(char *cmdline
,
287 unsigned long long system_ram
,
288 unsigned long long *crash_size
,
289 unsigned long long *crash_base
)
291 return __parse_crashkernel(cmdline
, system_ram
, crash_size
, crash_base
,
292 "crashkernel=", suffix_tbl
[SUFFIX_LOW
]);
296 * Add a dummy early_param handler to mark crashkernel= as a known command line
297 * parameter and suppress incorrect warnings in init/main.c.
299 static int __init
parse_crashkernel_dummy(char *arg
)
303 early_param("crashkernel", parse_crashkernel_dummy
);
305 Elf_Word
*append_elf_note(Elf_Word
*buf
, char *name
, unsigned int type
,
306 void *data
, size_t data_len
)
308 struct elf_note
*note
= (struct elf_note
*)buf
;
310 note
->n_namesz
= strlen(name
) + 1;
311 note
->n_descsz
= data_len
;
313 buf
+= DIV_ROUND_UP(sizeof(*note
), sizeof(Elf_Word
));
314 memcpy(buf
, name
, note
->n_namesz
);
315 buf
+= DIV_ROUND_UP(note
->n_namesz
, sizeof(Elf_Word
));
316 memcpy(buf
, data
, data_len
);
317 buf
+= DIV_ROUND_UP(data_len
, sizeof(Elf_Word
));
322 void final_note(Elf_Word
*buf
)
324 memset(buf
, 0, sizeof(struct elf_note
));
327 static void update_vmcoreinfo_note(void)
329 u32
*buf
= vmcoreinfo_note
;
331 if (!vmcoreinfo_size
)
333 buf
= append_elf_note(buf
, VMCOREINFO_NOTE_NAME
, 0, vmcoreinfo_data
,
338 void crash_update_vmcoreinfo_safecopy(void *ptr
)
341 memcpy(ptr
, vmcoreinfo_data
, vmcoreinfo_size
);
343 vmcoreinfo_data_safecopy
= ptr
;
346 void crash_save_vmcoreinfo(void)
348 if (!vmcoreinfo_note
)
351 /* Use the safe copy to generate vmcoreinfo note if have */
352 if (vmcoreinfo_data_safecopy
)
353 vmcoreinfo_data
= vmcoreinfo_data_safecopy
;
355 vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
356 update_vmcoreinfo_note();
359 void vmcoreinfo_append_str(const char *fmt
, ...)
366 r
= vscnprintf(buf
, sizeof(buf
), fmt
, args
);
369 r
= min(r
, (size_t)VMCOREINFO_BYTES
- vmcoreinfo_size
);
371 memcpy(&vmcoreinfo_data
[vmcoreinfo_size
], buf
, r
);
373 vmcoreinfo_size
+= r
;
377 * provide an empty default implementation here -- architecture
378 * code may override this
380 void __weak
arch_crash_save_vmcoreinfo(void)
383 phys_addr_t __weak
paddr_vmcoreinfo_note(void)
385 return __pa(vmcoreinfo_note
);
387 EXPORT_SYMBOL(paddr_vmcoreinfo_note
);
389 static int __init
crash_save_vmcoreinfo_init(void)
391 vmcoreinfo_data
= (unsigned char *)get_zeroed_page(GFP_KERNEL
);
392 if (!vmcoreinfo_data
) {
393 pr_warn("Memory allocation for vmcoreinfo_data failed\n");
397 vmcoreinfo_note
= alloc_pages_exact(VMCOREINFO_NOTE_SIZE
,
398 GFP_KERNEL
| __GFP_ZERO
);
399 if (!vmcoreinfo_note
) {
400 free_page((unsigned long)vmcoreinfo_data
);
401 vmcoreinfo_data
= NULL
;
402 pr_warn("Memory allocation for vmcoreinfo_note failed\n");
406 VMCOREINFO_OSRELEASE(init_uts_ns
.name
.release
);
407 VMCOREINFO_BUILD_ID();
408 VMCOREINFO_PAGESIZE(PAGE_SIZE
);
410 VMCOREINFO_SYMBOL(init_uts_ns
);
411 VMCOREINFO_OFFSET(uts_namespace
, name
);
412 VMCOREINFO_SYMBOL(node_online_map
);
414 VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir
);
416 VMCOREINFO_SYMBOL(_stext
);
417 VMCOREINFO_SYMBOL(vmap_area_list
);
420 VMCOREINFO_SYMBOL(mem_map
);
421 VMCOREINFO_SYMBOL(contig_page_data
);
423 #ifdef CONFIG_SPARSEMEM
424 VMCOREINFO_SYMBOL_ARRAY(mem_section
);
425 VMCOREINFO_LENGTH(mem_section
, NR_SECTION_ROOTS
);
426 VMCOREINFO_STRUCT_SIZE(mem_section
);
427 VMCOREINFO_OFFSET(mem_section
, section_mem_map
);
428 VMCOREINFO_NUMBER(SECTION_SIZE_BITS
);
429 VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS
);
431 VMCOREINFO_STRUCT_SIZE(page
);
432 VMCOREINFO_STRUCT_SIZE(pglist_data
);
433 VMCOREINFO_STRUCT_SIZE(zone
);
434 VMCOREINFO_STRUCT_SIZE(free_area
);
435 VMCOREINFO_STRUCT_SIZE(list_head
);
436 VMCOREINFO_SIZE(nodemask_t
);
437 VMCOREINFO_OFFSET(page
, flags
);
438 VMCOREINFO_OFFSET(page
, _refcount
);
439 VMCOREINFO_OFFSET(page
, mapping
);
440 VMCOREINFO_OFFSET(page
, lru
);
441 VMCOREINFO_OFFSET(page
, _mapcount
);
442 VMCOREINFO_OFFSET(page
, private);
443 VMCOREINFO_OFFSET(page
, compound_dtor
);
444 VMCOREINFO_OFFSET(page
, compound_order
);
445 VMCOREINFO_OFFSET(page
, compound_head
);
446 VMCOREINFO_OFFSET(pglist_data
, node_zones
);
447 VMCOREINFO_OFFSET(pglist_data
, nr_zones
);
448 #ifdef CONFIG_FLATMEM
449 VMCOREINFO_OFFSET(pglist_data
, node_mem_map
);
451 VMCOREINFO_OFFSET(pglist_data
, node_start_pfn
);
452 VMCOREINFO_OFFSET(pglist_data
, node_spanned_pages
);
453 VMCOREINFO_OFFSET(pglist_data
, node_id
);
454 VMCOREINFO_OFFSET(zone
, free_area
);
455 VMCOREINFO_OFFSET(zone
, vm_stat
);
456 VMCOREINFO_OFFSET(zone
, spanned_pages
);
457 VMCOREINFO_OFFSET(free_area
, free_list
);
458 VMCOREINFO_OFFSET(list_head
, next
);
459 VMCOREINFO_OFFSET(list_head
, prev
);
460 VMCOREINFO_OFFSET(vmap_area
, va_start
);
461 VMCOREINFO_OFFSET(vmap_area
, list
);
462 VMCOREINFO_LENGTH(zone
.free_area
, MAX_ORDER
);
463 log_buf_vmcoreinfo_setup();
464 VMCOREINFO_LENGTH(free_area
.free_list
, MIGRATE_TYPES
);
465 VMCOREINFO_NUMBER(NR_FREE_PAGES
);
466 VMCOREINFO_NUMBER(PG_lru
);
467 VMCOREINFO_NUMBER(PG_private
);
468 VMCOREINFO_NUMBER(PG_swapcache
);
469 VMCOREINFO_NUMBER(PG_swapbacked
);
470 VMCOREINFO_NUMBER(PG_slab
);
471 #ifdef CONFIG_MEMORY_FAILURE
472 VMCOREINFO_NUMBER(PG_hwpoison
);
474 VMCOREINFO_NUMBER(PG_head_mask
);
475 #define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy)
476 VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE
);
477 #ifdef CONFIG_HUGETLB_PAGE
478 VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR
);
479 #define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline)
480 VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE
);
483 arch_crash_save_vmcoreinfo();
484 update_vmcoreinfo_note();
489 subsys_initcall(crash_save_vmcoreinfo_init
);