1 // SPDX-License-Identifier: GPL-2.0-only 1
2 /*
3 * crash.c - kernel crash support code.
4 * Copyright (C) 2002-2004 Eric Biederman <eb
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 /* Location of the reserved area for the crash
27 struct resource crashk_res = {
28 .name = "Crash kernel",
29 .start = 0,
30 .end = 0,
31 .flags = IORESOURCE_BUSY | IORESOURCE_
32 .desc = IORES_DESC_CRASH_KERNEL
33 };
34 struct resource crashk_low_res = {
35 .name = "Crash kernel",
36 .start = 0,
37 .end = 0,
38 .flags = IORESOURCE_BUSY | IORESOURCE_
39 .desc = IORES_DESC_CRASH_KERNEL
40 };
41
42 /*
43 * parsing the "crashkernel" commandline
44 *
45 * this code is intended to be called from arc
46 */
47
48
49 /*
50 * This function parses command lines in the f
51 *
52 * crashkernel=ramsize-range:size[,...][@off
53 *
54 * The function returns 0 on success and -EINV
55 */
56 static int __init parse_crashkernel_mem(char *
57 unsign
58 unsign
59 unsign
60 {
61 char *cur = cmdline, *tmp;
62 unsigned long long total_mem = system_
63
64 /*
65 * Firmware sometimes reserves some me
66 * so the system memory size is less t
67 * size. Work around this by rounding
68 * which is enough for most test cases
69 */
70 total_mem = roundup(total_mem, SZ_128M
71
72 /* for each entry of the comma-separat
73 do {
74 unsigned long long start, end
75
76 /* get the start of the range
77 start = memparse(cur, &tmp);
78 if (cur == tmp) {
79 pr_warn("crashkernel:
80 return -EINVAL;
81 }
82 cur = tmp;
83 if (*cur != '-') {
84 pr_warn("crashkernel:
85 return -EINVAL;
86 }
87 cur++;
88
89 /* if no ':' is here, than we
90 if (*cur != ':') {
91 end = memparse(cur, &t
92 if (cur == tmp) {
93 pr_warn("crash
94 return -EINVAL
95 }
96 cur = tmp;
97 if (end <= start) {
98 pr_warn("crash
99 return -EINVAL
100 }
101 }
102
103 if (*cur != ':') {
104 pr_warn("crashkernel:
105 return -EINVAL;
106 }
107 cur++;
108
109 size = memparse(cur, &tmp);
110 if (cur == tmp) {
111 pr_warn("crashkernel:
112 return -EINVAL;
113 }
114 cur = tmp;
115 if (size >= total_mem) {
116 pr_warn("crashkernel:
117 return -EINVAL;
118 }
119
120 /* match ? */
121 if (total_mem >= start && tota
122 *crash_size = size;
123 break;
124 }
125 } while (*cur++ == ',');
126
127 if (*crash_size > 0) {
128 while (*cur && *cur != ' ' &&
129 cur++;
130 if (*cur == '@') {
131 cur++;
132 *crash_base = memparse
133 if (cur == tmp) {
134 pr_warn("crahs
135 return -EINVAL
136 }
137 }
138 } else
139 pr_info("crashkernel size resu
140
141 return 0;
142 }
143
144 /*
145 * That function parses "simple" (old) crashke
146 *
147 * crashkernel=size[@offset]
148 *
149 * It returns 0 on success and -EINVAL on fail
150 */
151 static int __init parse_crashkernel_simple(cha
152 uns
153 uns
154 {
155 char *cur = cmdline;
156
157 *crash_size = memparse(cmdline, &cur);
158 if (cmdline == cur) {
159 pr_warn("crashkernel: memory v
160 return -EINVAL;
161 }
162
163 if (*cur == '@')
164 *crash_base = memparse(cur+1,
165 else if (*cur != ' ' && *cur != '\0')
166 pr_warn("crashkernel: unrecogn
167 return -EINVAL;
168 }
169
170 return 0;
171 }
172
173 #define SUFFIX_HIGH 0
174 #define SUFFIX_LOW 1
175 #define SUFFIX_NULL 2
176 static __initdata char *suffix_tbl[] = {
177 [SUFFIX_HIGH] = ",high",
178 [SUFFIX_LOW] = ",low",
179 [SUFFIX_NULL] = NULL,
180 };
181
182 /*
183 * That function parses "suffix" crashkernel
184 *
185 * crashkernel=size,[high|low]
186 *
187 * It returns 0 on success and -EINVAL on fail
188 */
189 static int __init parse_crashkernel_suffix(cha
190 uns
191 con
192 {
193 char *cur = cmdline;
194
195 *crash_size = memparse(cmdline, &cur);
196 if (cmdline == cur) {
197 pr_warn("crashkernel: memory v
198 return -EINVAL;
199 }
200
201 /* check with suffix */
202 if (strncmp(cur, suffix, strlen(suffix
203 pr_warn("crashkernel: unrecogn
204 return -EINVAL;
205 }
206 cur += strlen(suffix);
207 if (*cur != ' ' && *cur != '\0') {
208 pr_warn("crashkernel: unrecogn
209 return -EINVAL;
210 }
211
212 return 0;
213 }
214
215 static __init char *get_last_crashkernel(char
216 const char *name,
217 const char *suffi
218 {
219 char *p = cmdline, *ck_cmdline = NULL;
220
221 /* find crashkernel and use the last o
222 p = strstr(p, name);
223 while (p) {
224 char *end_p = strchr(p, ' ');
225 char *q;
226
227 if (!end_p)
228 end_p = p + strlen(p);
229
230 if (!suffix) {
231 int i;
232
233 /* skip the one with a
234 for (i = 0; suffix_tbl
235 q = end_p - st
236 if (!strncmp(q
237 s
238 goto n
239 }
240 ck_cmdline = p;
241 } else {
242 q = end_p - strlen(suf
243 if (!strncmp(q, suffix
244 ck_cmdline = p
245 }
246 next:
247 p = strstr(p+1, name);
248 }
249
250 return ck_cmdline;
251 }
252
253 static int __init __parse_crashkernel(char *cm
254 unsigned long lon
255 unsigned long lon
256 unsigned long lon
257 const char *suffi
258 {
259 char *first_colon, *first_space;
260 char *ck_cmdline;
261 char *name = "crashkernel=";
262
263 BUG_ON(!crash_size || !crash_base);
264 *crash_size = 0;
265 *crash_base = 0;
266
267 ck_cmdline = get_last_crashkernel(cmdl
268 if (!ck_cmdline)
269 return -ENOENT;
270
271 ck_cmdline += strlen(name);
272
273 if (suffix)
274 return parse_crashkernel_suffi
275 suffix);
276 /*
277 * if the commandline contains a ':',
278 * syntax -- if not, it must be the cl
279 */
280 first_colon = strchr(ck_cmdline, ':');
281 first_space = strchr(ck_cmdline, ' ');
282 if (first_colon && (!first_space || fi
283 return parse_crashkernel_mem(c
284 crash_size, cr
285
286 return parse_crashkernel_simple(ck_cmd
287 }
288
289 /*
290 * That function is the entry point for comman
291 * called from the arch-specific code.
292 *
293 * If crashkernel=,high|low is supported on ar
294 * should be passed to parameters 'low_size' a
295 */
296 int __init parse_crashkernel(char *cmdline,
297 unsigned long lon
298 unsigned long lon
299 unsigned long lon
300 unsigned long lon
301 bool *high)
302 {
303 int ret;
304
305 /* crashkernel=X[@offset] */
306 ret = __parse_crashkernel(cmdline, sys
307 crash_base, NU
308 #ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RES
309 /*
310 * If non-NULL 'high' passed in and no
311 * setting detected, try parsing crash
312 */
313 if (high && ret == -ENOENT) {
314 ret = __parse_crashkernel(cmdl
315 crash_base, su
316 if (ret || !*crash_size)
317 return -EINVAL;
318
319 /*
320 * crashkernel=Y,low can be sp
321 * is not allowed.
322 */
323 ret = __parse_crashkernel(cmdl
324 crash_base, su
325 if (ret == -ENOENT) {
326 *low_size = DEFAULT_CR
327 ret = 0;
328 } else if (ret) {
329 return ret;
330 }
331
332 *high = true;
333 }
334 #endif
335 if (!*crash_size)
336 ret = -EINVAL;
337
338 if (*crash_size >= system_ram)
339 ret = -EINVAL;
340
341 return ret;
342 }
343
344 /*
345 * Add a dummy early_param handler to mark cra
346 * parameter and suppress incorrect warnings i
347 */
348 static int __init parse_crashkernel_dummy(char
349 {
350 return 0;
351 }
352 early_param("crashkernel", parse_crashkernel_d
353
354 #ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RES
355 static int __init reserve_crashkernel_low(unsi
356 {
357 #ifdef CONFIG_64BIT
358 unsigned long long low_base;
359
360 low_base = memblock_phys_alloc_range(l
361 if (!low_base) {
362 pr_err("cannot allocate crashk
363 return -ENOMEM;
364 }
365
366 pr_info("crashkernel low memory reserv
367 low_base, low_base + low_size,
368
369 crashk_low_res.start = low_base;
370 crashk_low_res.end = low_base + low_
371 #ifdef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
372 insert_resource(&iomem_resource, &cras
373 #endif
374 #endif
375 return 0;
376 }
377
378 void __init reserve_crashkernel_generic(char *
379 unsigned long lon
380 unsigned long lon
381 unsigned long lon
382 bool high)
383 {
384 unsigned long long search_end = CRASH_
385 bool fixed_base = false;
386
387 /* User specifies base address explici
388 if (crash_base) {
389 fixed_base = true;
390 search_base = crash_base;
391 search_end = crash_base + cras
392 } else if (high) {
393 search_base = CRASH_ADDR_LOW_M
394 search_end = CRASH_ADDR_HIGH_M
395 }
396
397 retry:
398 crash_base = memblock_phys_alloc_range
399
400 if (!crash_base) {
401 /*
402 * For crashkernel=size[KMG]@o
403 * message if can't reserve th
404 */
405 if (fixed_base) {
406 pr_warn("crashkernel r
407 return;
408 }
409
410 /*
411 * For crashkernel=size[KMG],
412 * low memory, fall back to hi
413 * low memory will be reserved
414 */
415 if (!high && search_end == CRA
416 search_end = CRASH_ADD
417 search_base = CRASH_AD
418 crash_low_size = DEFAU
419 goto retry;
420 }
421
422 /*
423 * For crashkernel=size[KMG],h
424 * for high memory, fall back
425 */
426 if (high && search_end == CRAS
427 search_end = CRASH_ADD
428 search_base = 0;
429 if (search_end != CRAS
430 goto retry;
431 }
432 pr_warn("cannot allocate crash
433 crash_size);
434 return;
435 }
436
437 if ((crash_base >= CRASH_ADDR_LOW_MAX)
438 crash_low_size && reserve_crashke
439 memblock_phys_free(crash_base,
440 return;
441 }
442
443 pr_info("crashkernel reserved: 0x%016l
444 crash_base, crash_base + crash
445
446 /*
447 * The crashkernel memory will be remo
448 * map. Inform kmemleak so that it won
449 */
450 kmemleak_ignore_phys(crash_base);
451 if (crashk_low_res.end)
452 kmemleak_ignore_phys(crashk_lo
453
454 crashk_res.start = crash_base;
455 crashk_res.end = crash_base + crash_si
456 #ifdef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
457 insert_resource(&iomem_resource, &cras
458 #endif
459 }
460
461 #ifndef HAVE_ARCH_ADD_CRASH_RES_TO_IOMEM_EARLY
462 static __init int insert_crashkernel_resources
463 {
464 if (crashk_res.start < crashk_res.end)
465 insert_resource(&iomem_resourc
466
467 if (crashk_low_res.start < crashk_low_
468 insert_resource(&iomem_resourc
469
470 return 0;
471 }
472 early_initcall(insert_crashkernel_resources);
473 #endif
474 #endif
475
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