ram.c 15.2 KB
Newer Older
1
2
3
4
/*
 * RAM Oops/Panic logger
 *
 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
Kees Cook's avatar
Kees Cook committed
5
 * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

23
24
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

25
#include <linux/kernel.h>
26
#include <linux/err.h>
27
#include <linux/module.h>
28
#include <linux/version.h>
Kees Cook's avatar
Kees Cook committed
29
#include <linux/pstore.h>
30
31
32
#include <linux/time.h>
#include <linux/io.h>
#include <linux/ioport.h>
33
#include <linux/platform_device.h>
34
#include <linux/slab.h>
35
#include <linux/compiler.h>
36
#include <linux/pstore_ram.h>
37
38

#define RAMOOPS_KERNMSG_HDR "===="
39
#define MIN_MEM_SIZE 4096UL
40

41
42
43
44
static ulong record_size = MIN_MEM_SIZE;
module_param(record_size, ulong, 0400);
MODULE_PARM_DESC(record_size,
		"size of each dump done on oops/panic");
45

46
47
48
49
static ulong ramoops_console_size = MIN_MEM_SIZE;
module_param_named(console_size, ramoops_console_size, ulong, 0400);
MODULE_PARM_DESC(console_size, "size of kernel console log");

50
51
52
53
static ulong ramoops_ftrace_size = MIN_MEM_SIZE;
module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400);
MODULE_PARM_DESC(ftrace_size, "size of ftrace log");

54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
static ulong mem_address;
module_param(mem_address, ulong, 0400);
MODULE_PARM_DESC(mem_address,
		"start of reserved RAM used to store oops/panic logs");

static ulong mem_size;
module_param(mem_size, ulong, 0400);
MODULE_PARM_DESC(mem_size,
		"size of reserved RAM used to store oops/panic logs");

static int dump_oops = 1;
module_param(dump_oops, int, 0600);
MODULE_PARM_DESC(dump_oops,
		"set to 1 to dump oopses, 0 to only dump panics (default 1)");

Anton Vorontsov's avatar
Anton Vorontsov committed
69
70
71
static int ramoops_ecc;
module_param_named(ecc, ramoops_ecc, int, 0600);
MODULE_PARM_DESC(ramoops_ecc,
72
73
74
		"if non-zero, the option enables ECC support and specifies "
		"ECC buffer size in bytes (1 is a special value, means 16 "
		"bytes ECC)");
Anton Vorontsov's avatar
Anton Vorontsov committed
75

Kees Cook's avatar
Kees Cook committed
76
struct ramoops_context {
77
	struct persistent_ram_zone **przs;
78
	struct persistent_ram_zone *cprz;
79
	struct persistent_ram_zone *fprz;
80
81
	phys_addr_t phys_addr;
	unsigned long size;
Kees Cook's avatar
Kees Cook committed
82
	size_t record_size;
83
	size_t console_size;
84
	size_t ftrace_size;
85
	int dump_oops;
86
	struct persistent_ram_ecc_info ecc_info;
87
88
	unsigned int max_dump_cnt;
	unsigned int dump_write_cnt;
89
	/* _read_cnt need clear on ramoops_pstore_open */
90
	unsigned int dump_read_cnt;
91
	unsigned int console_read_cnt;
92
	unsigned int ftrace_read_cnt;
Kees Cook's avatar
Kees Cook committed
93
94
	struct pstore_info pstore;
};
95

96
97
98
static struct platform_device *dummy;
static struct ramoops_platform_data *dummy_data;

Kees Cook's avatar
Kees Cook committed
99
100
101
102
static int ramoops_pstore_open(struct pstore_info *psi)
{
	struct ramoops_context *cxt = psi->data;

103
	cxt->dump_read_cnt = 0;
104
	cxt->console_read_cnt = 0;
105
	cxt->ftrace_read_cnt = 0;
Kees Cook's avatar
Kees Cook committed
106
107
108
	return 0;
}

109
110
111
112
113
114
115
116
117
118
119
120
121
static struct persistent_ram_zone *
ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
		     u64 *id,
		     enum pstore_type_id *typep, enum pstore_type_id type,
		     bool update)
{
	struct persistent_ram_zone *prz;
	int i = (*c)++;

	if (i >= max)
		return NULL;

	prz = przs[i];
122
123
	if (!prz)
		return NULL;
124

125
126
	/* Update old/shadowed buffer. */
	if (update)
127
		persistent_ram_save_old(prz);
128
129
130

	if (!persistent_ram_old_size(prz))
		return NULL;
131
132
133
134
135
136
137

	*typep = type;
	*id = i;

	return prz;
}

138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
static void ramoops_read_kmsg_hdr(char *buffer, struct timespec *time,
				  bool *compressed)
{
	char data_type;

	if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
			&time->tv_sec, &time->tv_nsec, &data_type) == 3) {
		if (data_type == 'C')
			*compressed = true;
		else
			*compressed = false;
	} else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
			&time->tv_sec, &time->tv_nsec) == 2) {
			*compressed = false;
	} else {
		time->tv_sec = 0;
		time->tv_nsec = 0;
		*compressed = false;
	}
}

Kees Cook's avatar
Kees Cook committed
159
static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
160
				   int *count, struct timespec *time,
161
162
				   char **buf, bool *compressed,
				   struct pstore_info *psi)
163
{
Kees Cook's avatar
Kees Cook committed
164
	ssize_t size;
165
	ssize_t ecc_notice_size;
Kees Cook's avatar
Kees Cook committed
166
	struct ramoops_context *cxt = psi->data;
167
	struct persistent_ram_zone *prz;
Kees Cook's avatar
Kees Cook committed
168

169
170
171
	prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,
				   cxt->max_dump_cnt, id, type,
				   PSTORE_TYPE_DMESG, 1);
172
173
174
	if (!prz)
		prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
					   1, id, type, PSTORE_TYPE_CONSOLE, 0);
175
176
177
	if (!prz)
		prz = ramoops_get_next_prz(&cxt->fprz, &cxt->ftrace_read_cnt,
					   1, id, type, PSTORE_TYPE_FTRACE, 0);
178
179
	if (!prz)
		return 0;
180
181

	size = persistent_ram_old_size(prz);
182
183
184
185
186

	/* ECC correction notice */
	ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);

	*buf = kmalloc(size + ecc_notice_size + 1, GFP_KERNEL);
Kees Cook's avatar
Kees Cook committed
187
188
189
	if (*buf == NULL)
		return -ENOMEM;

190
	memcpy(*buf, persistent_ram_old(prz), size);
191
	ramoops_read_kmsg_hdr(*buf, time, compressed);
192
193
194
	persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1);

	return size + ecc_notice_size;
Kees Cook's avatar
Kees Cook committed
195
196
}

197
198
static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
				     bool compressed)
199
200
{
	char *hdr;
201
	struct timespec timestamp;
202
203
	size_t len;

204
205
206
207
208
	/* Report zeroed timestamp if called before timekeeping has resumed. */
	if (__getnstimeofday(&timestamp)) {
		timestamp.tv_sec = 0;
		timestamp.tv_nsec = 0;
	}
209
210
211
	hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
		(long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000),
		compressed ? 'C' : 'D');
212
213
214
215
216
217
218
219
	WARN_ON_ONCE(!hdr);
	len = hdr ? strlen(hdr) : 0;
	persistent_ram_write(prz, hdr, len);
	kfree(hdr);

	return len;
}

220
221
222
static int notrace ramoops_pstore_write_buf(enum pstore_type_id type,
					    enum kmsg_dump_reason reason,
					    u64 *id, unsigned int part,
223
					    const char *buf,
224
					    bool compressed, size_t size,
225
					    struct pstore_info *psi)
Kees Cook's avatar
Kees Cook committed
226
227
{
	struct ramoops_context *cxt = psi->data;
228
	struct persistent_ram_zone *prz;
229
	size_t hlen;
Kees Cook's avatar
Kees Cook committed
230

231
232
233
	if (type == PSTORE_TYPE_CONSOLE) {
		if (!cxt->cprz)
			return -ENOMEM;
234
		persistent_ram_write(cxt->cprz, buf, size);
235
		return 0;
236
237
238
239
240
	} else if (type == PSTORE_TYPE_FTRACE) {
		if (!cxt->fprz)
			return -ENOMEM;
		persistent_ram_write(cxt->fprz, buf, size);
		return 0;
241
242
	}

Kees Cook's avatar
Kees Cook committed
243
244
	if (type != PSTORE_TYPE_DMESG)
		return -EINVAL;
245

Kees Cook's avatar
Kees Cook committed
246
247
248
	/* Out of the various dmesg dump types, ramoops is currently designed
	 * to only store crash logs, rather than storing general kernel logs.
	 */
249
	if (reason != KMSG_DUMP_OOPS &&
WANG Cong's avatar
WANG Cong committed
250
	    reason != KMSG_DUMP_PANIC)
Kees Cook's avatar
Kees Cook committed
251
		return -EINVAL;
252

Kees Cook's avatar
Kees Cook committed
253
	/* Skip Oopes when configured to do so. */
254
	if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
Kees Cook's avatar
Kees Cook committed
255
256
257
258
259
260
261
262
263
		return -EINVAL;

	/* Explicitly only take the first part of any new crash.
	 * If our buffer is larger than kmsg_bytes, this can never happen,
	 * and if our buffer is smaller than kmsg_bytes, we don't want the
	 * report split across multiple records.
	 */
	if (part != 1)
		return -ENOSPC;
264

265
266
267
268
269
	if (!cxt->przs)
		return -ENOSPC;

	prz = cxt->przs[cxt->dump_write_cnt];

270
	hlen = ramoops_write_kmsg_hdr(prz, compressed);
271
272
	if (size + hlen > prz->buffer_size)
		size = prz->buffer_size - hlen;
273
	persistent_ram_write(prz, buf, size);
274

275
	cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
Kees Cook's avatar
Kees Cook committed
276
277
278
279

	return 0;
}

280
static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count,
281
				struct timespec time, struct pstore_info *psi)
Kees Cook's avatar
Kees Cook committed
282
283
{
	struct ramoops_context *cxt = psi->data;
284
	struct persistent_ram_zone *prz;
Kees Cook's avatar
Kees Cook committed
285

286
287
288
289
290
291
292
293
294
	switch (type) {
	case PSTORE_TYPE_DMESG:
		if (id >= cxt->max_dump_cnt)
			return -EINVAL;
		prz = cxt->przs[id];
		break;
	case PSTORE_TYPE_CONSOLE:
		prz = cxt->cprz;
		break;
295
296
297
	case PSTORE_TYPE_FTRACE:
		prz = cxt->fprz;
		break;
298
	default:
Kees Cook's avatar
Kees Cook committed
299
		return -EINVAL;
300
	}
Kees Cook's avatar
Kees Cook committed
301

302
303
	persistent_ram_free_old(prz);
	persistent_ram_zap(prz);
Kees Cook's avatar
Kees Cook committed
304
305

	return 0;
306
307
}

Kees Cook's avatar
Kees Cook committed
308
309
310
311
312
313
static struct ramoops_context oops_cxt = {
	.pstore = {
		.owner	= THIS_MODULE,
		.name	= "ramoops",
		.open	= ramoops_pstore_open,
		.read	= ramoops_pstore_read,
314
		.write_buf	= ramoops_pstore_write_buf,
Kees Cook's avatar
Kees Cook committed
315
316
317
318
		.erase	= ramoops_pstore_erase,
	},
};

319
320
321
322
323
324
325
static void ramoops_free_przs(struct ramoops_context *cxt)
{
	int i;

	if (!cxt->przs)
		return;

326
	for (i = 0; !IS_ERR_OR_NULL(cxt->przs[i]); i++)
327
328
329
330
		persistent_ram_free(cxt->przs[i]);
	kfree(cxt->przs);
}

331
332
static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
			     phys_addr_t *paddr, size_t dump_mem_sz)
333
334
335
336
337
338
339
{
	int err = -ENOMEM;
	int i;

	if (!cxt->record_size)
		return 0;

340
341
342
343
344
	if (*paddr + dump_mem_sz - cxt->phys_addr > cxt->size) {
		dev_err(dev, "no room for dumps\n");
		return -ENOMEM;
	}

345
346
347
348
349
350
351
352
353
354
355
356
357
358
	cxt->max_dump_cnt = dump_mem_sz / cxt->record_size;
	if (!cxt->max_dump_cnt)
		return -ENOMEM;

	cxt->przs = kzalloc(sizeof(*cxt->przs) * cxt->max_dump_cnt,
			     GFP_KERNEL);
	if (!cxt->przs) {
		dev_err(dev, "failed to initialize a prz array for dumps\n");
		return -ENOMEM;
	}

	for (i = 0; i < cxt->max_dump_cnt; i++) {
		size_t sz = cxt->record_size;

359
360
		cxt->przs[i] = persistent_ram_new(*paddr, sz, 0,
						  &cxt->ecc_info);
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
		if (IS_ERR(cxt->przs[i])) {
			err = PTR_ERR(cxt->przs[i]);
			dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
				sz, (unsigned long long)*paddr, err);
			goto fail_prz;
		}
		*paddr += sz;
	}

	return 0;
fail_prz:
	ramoops_free_przs(cxt);
	return err;
}

376
377
378
static int ramoops_init_prz(struct device *dev, struct ramoops_context *cxt,
			    struct persistent_ram_zone **prz,
			    phys_addr_t *paddr, size_t sz, u32 sig)
379
380
381
382
{
	if (!sz)
		return 0;

383
384
385
386
	if (*paddr + sz - cxt->phys_addr > cxt->size) {
		dev_err(dev, "no room for mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
			sz, (unsigned long long)*paddr,
			cxt->size, (unsigned long long)cxt->phys_addr);
387
		return -ENOMEM;
388
	}
389

390
	*prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info);
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
	if (IS_ERR(*prz)) {
		int err = PTR_ERR(*prz);

		dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
			sz, (unsigned long long)*paddr, err);
		return err;
	}

	persistent_ram_zap(*prz);

	*paddr += sz;

	return 0;
}

406
static int ramoops_probe(struct platform_device *pdev)
407
{
408
	struct device *dev = &pdev->dev;
409
	struct ramoops_platform_data *pdata = pdev->dev.platform_data;
410
	struct ramoops_context *cxt = &oops_cxt;
411
412
	size_t dump_mem_sz;
	phys_addr_t paddr;
413
414
	int err = -EINVAL;

Kees Cook's avatar
Kees Cook committed
415
416
417
	/* Only a single ramoops area allowed at a time, so fail extra
	 * probes.
	 */
418
	if (cxt->max_dump_cnt)
Kees Cook's avatar
Kees Cook committed
419
420
		goto fail_out;

421
422
	if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
			!pdata->ftrace_size)) {
423
		pr_err("The memory size and the record/console size must be "
424
			"non-zero\n");
Kees Cook's avatar
Kees Cook committed
425
		goto fail_out;
426
427
	}

428
	if (pdata->record_size && !is_power_of_2(pdata->record_size))
429
		pdata->record_size = rounddown_pow_of_two(pdata->record_size);
430
	if (pdata->console_size && !is_power_of_2(pdata->console_size))
431
		pdata->console_size = rounddown_pow_of_two(pdata->console_size);
432
	if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))
433
		pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);
434

435
436
	cxt->size = pdata->mem_size;
	cxt->phys_addr = pdata->mem_address;
437
	cxt->record_size = pdata->record_size;
438
	cxt->console_size = pdata->console_size;
439
	cxt->ftrace_size = pdata->ftrace_size;
440
	cxt->dump_oops = pdata->dump_oops;
441
	cxt->ecc_info = pdata->ecc_info;
442

443
	paddr = cxt->phys_addr;
444

445
	dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size;
446
	err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
447
448
449
	if (err)
		goto fail_out;

450
451
	err = ramoops_init_prz(dev, cxt, &cxt->cprz, &paddr,
			       cxt->console_size, 0);
452
453
454
	if (err)
		goto fail_init_cprz;

455
456
	err = ramoops_init_prz(dev, cxt, &cxt->fprz, &paddr, cxt->ftrace_size,
			       LINUX_VERSION_CODE);
457
458
459
460
	if (err)
		goto fail_init_fprz;

	if (!cxt->przs && !cxt->cprz && !cxt->fprz) {
461
		pr_err("memory size too small, minimum is %zu\n",
462
463
			cxt->console_size + cxt->record_size +
			cxt->ftrace_size);
464
		err = -EINVAL;
465
		goto fail_cnt;
466
467
	}

Kees Cook's avatar
Kees Cook committed
468
	cxt->pstore.data = cxt;
469
	/*
470
471
472
473
	 * Console can handle any buffer size, so prefer LOG_LINE_MAX. If we
	 * have to handle dumps, we must have at least record_size buffer. And
	 * for ftrace, bufsize is irrelevant (if bufsize is 0, buf will be
	 * ZERO_SIZE_PTR).
474
	 */
475
476
477
	if (cxt->console_size)
		cxt->pstore.bufsize = 1024; /* LOG_LINE_MAX */
	cxt->pstore.bufsize = max(cxt->record_size, cxt->pstore.bufsize);
Kees Cook's avatar
Kees Cook committed
478
479
480
481
	cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
	spin_lock_init(&cxt->pstore.buf_lock);
	if (!cxt->pstore.buf) {
		pr_err("cannot allocate pstore buffer\n");
482
		err = -ENOMEM;
Kees Cook's avatar
Kees Cook committed
483
484
485
486
		goto fail_clear;
	}

	err = pstore_register(&cxt->pstore);
487
	if (err) {
Kees Cook's avatar
Kees Cook committed
488
		pr_err("registering with pstore failed\n");
489
		goto fail_buf;
490
491
	}

492
493
494
495
496
497
498
499
500
	/*
	 * Update the module parameter variables as well so they are visible
	 * through /sys/module/ramoops/parameters/
	 */
	mem_size = pdata->mem_size;
	mem_address = pdata->mem_address;
	record_size = pdata->record_size;
	dump_oops = pdata->dump_oops;

501
	pr_info("attached 0x%lx@0x%llx, ecc: %d/%d\n",
502
		cxt->size, (unsigned long long)cxt->phys_addr,
503
		cxt->ecc_info.ecc_size, cxt->ecc_info.block_size);
Kees Cook's avatar
Kees Cook committed
504

505
506
	return 0;

Kees Cook's avatar
Kees Cook committed
507
508
509
510
fail_buf:
	kfree(cxt->pstore.buf);
fail_clear:
	cxt->pstore.bufsize = 0;
511
	cxt->max_dump_cnt = 0;
512
fail_cnt:
513
514
	kfree(cxt->fprz);
fail_init_fprz:
515
516
	kfree(cxt->cprz);
fail_init_cprz:
517
	ramoops_free_przs(cxt);
Kees Cook's avatar
Kees Cook committed
518
fail_out:
519
520
521
	return err;
}

522
static int __exit ramoops_remove(struct platform_device *pdev)
523
{
Kees Cook's avatar
Kees Cook committed
524
525
526
527
#if 0
	/* TODO(kees): We cannot unload ramoops since pstore doesn't support
	 * unregistering yet.
	 */
528
529
530
531
	struct ramoops_context *cxt = &oops_cxt;

	iounmap(cxt->virt_addr);
	release_mem_region(cxt->phys_addr, cxt->size);
532
	cxt->max_dump_cnt = 0;
Kees Cook's avatar
Kees Cook committed
533
534
535
536
537

	/* TODO(kees): When pstore supports unregistering, call it here. */
	kfree(cxt->pstore.buf);
	cxt->pstore.bufsize = 0;

538
	return 0;
Kees Cook's avatar
Kees Cook committed
539
540
#endif
	return -EBUSY;
541
542
}

543
static struct platform_driver ramoops_driver = {
544
	.probe		= ramoops_probe,
545
546
547
548
549
550
551
	.remove		= __exit_p(ramoops_remove),
	.driver		= {
		.name	= "ramoops",
		.owner	= THIS_MODULE,
	},
};

552
static void ramoops_register_dummy(void)
553
{
554
555
556
557
558
559
560
561
562
	if (!mem_size)
		return;

	pr_info("using module parameters\n");

	dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
	if (!dummy_data) {
		pr_info("could not allocate pdata\n");
		return;
563
564
	}

565
566
567
568
	dummy_data->mem_size = mem_size;
	dummy_data->mem_address = mem_address;
	dummy_data->record_size = record_size;
	dummy_data->console_size = ramoops_console_size;
569
	dummy_data->ftrace_size = ramoops_ftrace_size;
570
	dummy_data->dump_oops = dump_oops;
571
572
573
574
	/*
	 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
	 * (using 1 byte for ECC isn't much of use anyway).
	 */
575
	dummy_data->ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc;
576
577
578
579
580
581
582
583
584
585
586
587
588

	dummy = platform_device_register_data(NULL, "ramoops", -1,
			dummy_data, sizeof(struct ramoops_platform_data));
	if (IS_ERR(dummy)) {
		pr_info("could not create platform device: %ld\n",
			PTR_ERR(dummy));
	}
}

static int __init ramoops_init(void)
{
	ramoops_register_dummy();
	return platform_driver_register(&ramoops_driver);
589
}
590
postcore_initcall(ramoops_init);
591
592
593
594

static void __exit ramoops_exit(void)
{
	platform_driver_unregister(&ramoops_driver);
595
	platform_device_unregister(dummy);
596
	kfree(dummy_data);
597
}
598
599
600
601
602
module_exit(ramoops_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");