summaryrefslogtreecommitdiff
path: root/modutils/modprobe.c
blob: ab35628f488a6c2e72fcfae9cdf6ceb3cd0d7d49 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
/* vi: set sw=4 ts=4: */
/*
 * Modprobe written from scratch for BusyBox
 *
 * Copyright (c) 2008 Timo Teras <timo.teras@iki.fi>
 * Copyright (c) 2008 Vladimir Dronnikov
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

/* Note that unlike older versions of modules.dep/depmod (busybox and m-i-t),
 * we expect the full dependency list to be specified in modules.dep.
 * Older versions would only export the direct dependency list.
 */
#include "libbb.h"
#include "modutils.h"
#include <sys/utsname.h>
#include <fnmatch.h>

//#define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
#define DBG(...) ((void)0)

//usage:#if !ENABLE_MODPROBE_SMALL
//usage:#define modprobe_notes_usage
//usage:	"modprobe can (un)load a stack of modules, passing each module options (when\n"
//usage:	"loading). modprobe uses a configuration file to determine what option(s) to\n"
//usage:	"pass each module it loads.\n"
//usage:	"\n"
//usage:	"The configuration file is searched (in this order):\n"
//usage:	"\n"
//usage:	"    /etc/modprobe.conf (2.6 only)\n"
//usage:	"    /etc/modules.conf\n"
//usage:	"    /etc/conf.modules (deprecated)\n"
//usage:	"\n"
//usage:	"They all have the same syntax (see below). If none is present, it is\n"
//usage:	"_not_ an error; each loaded module is then expected to load without\n"
//usage:	"options. Once a file is found, the others are tested for.\n"
//usage:	"\n"
//usage:	"/etc/modules.conf entry format:\n"
//usage:	"\n"
//usage:	"  alias <alias_name> <mod_name>\n"
//usage:	"    Makes it possible to modprobe alias_name, when there is no such module.\n"
//usage:	"    It makes sense if your mod_name is long, or you want a more representative\n"
//usage:	"    name for that module (eg. 'scsi' in place of 'aha7xxx').\n"
//usage:	"    This makes it also possible to use a different set of options (below) for\n"
//usage:	"    the module and the alias.\n"
//usage:	"    A module can be aliased more than once.\n"
//usage:	"\n"
//usage:	"  options <mod_name|alias_name> <symbol=value...>\n"
//usage:	"    When loading module mod_name (or the module aliased by alias_name), pass\n"
//usage:	"    the \"symbol=value\" pairs as option to that module.\n"
//usage:	"\n"
//usage:	"Sample /etc/modules.conf file:\n"
//usage:	"\n"
//usage:	"  options tulip irq=3\n"
//usage:	"  alias tulip tulip2\n"
//usage:	"  options tulip2 irq=4 io=0x308\n"
//usage:	"\n"
//usage:	"Other functionality offered by 'classic' modprobe is not available in\n"
//usage:	"this implementation.\n"
//usage:	"\n"
//usage:	"If module options are present both in the config file, and on the command line,\n"
//usage:	"then the options from the command line will be passed to the module _after_\n"
//usage:	"the options from the config file. That way, you can have defaults in the config\n"
//usage:	"file, and override them for a specific usage from the command line.\n"
//usage:#define modprobe_example_usage
//usage:       "(with the above /etc/modules.conf):\n\n"
//usage:       "$ modprobe tulip\n"
//usage:       "   will load the module 'tulip' with default option 'irq=3'\n\n"
//usage:       "$ modprobe tulip irq=5\n"
//usage:       "   will load the module 'tulip' with option 'irq=5', thus overriding the default\n\n"
//usage:       "$ modprobe tulip2\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308',\n"
//usage:       "   which are the default for alias 'tulip2'\n\n"
//usage:       "$ modprobe tulip2 irq=8\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308 irq=8',\n"
//usage:       "   which are the default for alias 'tulip2' overridden by the option 'irq=8'\n\n"
//usage:       "   from the command line\n\n"
//usage:       "$ modprobe tulip2 irq=2 io=0x210\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308 irq=4 io=0x210',\n"
//usage:       "   which are the default for alias 'tulip2' overridden by the options 'irq=2 io=0x210'\n\n"
//usage:       "   from the command line\n"
//usage:
//usage:#define modprobe_trivial_usage
//usage:	"[-alrqvs"
//usage:	IF_FEATURE_MODPROBE_BLACKLIST("b")
//usage:	"] MODULE [symbol=value]..."
//usage:#define modprobe_full_usage "\n\n"
//usage:       "Options:"
//usage:     "\n	-a	Load multiple MODULEs"
//usage:     "\n	-l	List (MODULE is a pattern)"
//usage:     "\n	-r	Remove MODULE (stacks) or do autoclean"
//usage:     "\n	-q	Quiet"
//usage:     "\n	-v	Verbose"
//usage:     "\n	-s	Log to syslog"
//usage:	IF_FEATURE_MODPROBE_BLACKLIST(
//usage:     "\n	-b	Apply blacklist to module names too"
//usage:	)
//usage:#endif /* !ENABLE_MODPROBE_SMALL */

/* Note that usage text doesn't document various 2.4 options
 * we pull in through INSMOD_OPTS define */

#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--ar:a--lr:r--al"
#define MODPROBE_OPTS  "alr" IF_FEATURE_MODPROBE_BLACKLIST("b")
//#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--acr:a--lr:r--al"
//#define MODPROBE_OPTS  "acd:lnrt:C:" IF_FEATURE_MODPROBE_BLACKLIST("b")
enum {
	MODPROBE_OPT_INSERT_ALL = (INSMOD_OPT_UNUSED << 0), /* a */
	//MODPROBE_OPT_DUMP_ONLY= (INSMOD_OPT_UNUSED << x), /* c */
	//MODPROBE_OPT_DIRNAME  = (INSMOD_OPT_UNUSED << x), /* d */
	MODPROBE_OPT_LIST_ONLY  = (INSMOD_OPT_UNUSED << 1), /* l */
	//MODPROBE_OPT_SHOW_ONLY= (INSMOD_OPT_UNUSED << x), /* n */
	MODPROBE_OPT_REMOVE     = (INSMOD_OPT_UNUSED << 2), /* r */
	//MODPROBE_OPT_RESTRICT = (INSMOD_OPT_UNUSED << x), /* t */
	//MODPROBE_OPT_VERONLY  = (INSMOD_OPT_UNUSED << x), /* V */
	//MODPROBE_OPT_CONFIGFILE=(INSMOD_OPT_UNUSED << x), /* C */
	MODPROBE_OPT_BLACKLIST  = (INSMOD_OPT_UNUSED << 3) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
};

#define MODULE_FLAG_LOADED              0x0001
#define MODULE_FLAG_NEED_DEPS           0x0002
/* "was seen in modules.dep": */
#define MODULE_FLAG_FOUND_IN_MODDEP     0x0004
#define MODULE_FLAG_BLACKLISTED         0x0008

struct module_entry { /* I'll call it ME. */
	unsigned flags;
	char *modname; /* stripped of /path/, .ext and s/-/_/g */
	const char *probed_name; /* verbatim as seen on cmdline */
	char *options; /* options from config files */
	llist_t *realnames; /* strings. if this module is an alias, */
	/* real module name is one of these. */
//Can there really be more than one? Example from real kernel?
	llist_t *deps; /* strings. modules we depend on */
};

struct globals {
	llist_t *db; /* MEs of all modules ever seen (caching for speed) */
	llist_t *probes; /* MEs of module(s) requested on cmdline */
	char *cmdline_mopts; /* module options from cmdline */
	int num_unresolved_deps;
	/* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
	smallint need_symbols;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)


static int read_config(const char *path);

static char *gather_options_str(char *opts, const char *append)
{
	/* Speed-optimized. We call gather_options_str many times. */
	if (append) {
		if (opts == NULL) {
			opts = xstrdup(append);
		} else {
			int optlen = strlen(opts);
			opts = xrealloc(opts, optlen + strlen(append) + 2);
			sprintf(opts + optlen, " %s", append);
		}
	}
	return opts;
}

static struct module_entry *helper_get_module(const char *module, int create)
{
	char modname[MODULE_NAME_LEN];
	struct module_entry *e;
	llist_t *l;

	filename2modname(module, modname);
	for (l = G.db; l != NULL; l = l->link) {
		e = (struct module_entry *) l->data;
		if (strcmp(e->modname, modname) == 0)
			return e;
	}
	if (!create)
		return NULL;

	e = xzalloc(sizeof(*e));
	e->modname = xstrdup(modname);
	llist_add_to(&G.db, e);

	return e;
}
static struct module_entry *get_or_add_modentry(const char *module)
{
	return helper_get_module(module, 1);
}
static struct module_entry *get_modentry(const char *module)
{
	return helper_get_module(module, 0);
}

static void add_probe(const char *name)
{
	struct module_entry *m;

	m = get_or_add_modentry(name);
	if (!(option_mask32 & MODPROBE_OPT_REMOVE)
	 && (m->flags & MODULE_FLAG_LOADED)
	) {
		DBG("skipping %s, it is already loaded", name);
		return;
	}

	DBG("queuing %s", name);
	m->probed_name = name;
	m->flags |= MODULE_FLAG_NEED_DEPS;
	llist_add_to_end(&G.probes, m);
	G.num_unresolved_deps++;
	if (ENABLE_FEATURE_MODUTILS_SYMBOLS
	 && strncmp(m->modname, "symbol:", 7) == 0
	) {
		G.need_symbols = 1;
	}
}

static int FAST_FUNC config_file_action(const char *filename,
					struct stat *statbuf UNUSED_PARAM,
					void *userdata UNUSED_PARAM,
					int depth UNUSED_PARAM)
{
	char *tokens[3];
	parser_t *p;
	struct module_entry *m;
	int rc = TRUE;

	if (bb_basename(filename)[0] == '.')
		goto error;

	p = config_open2(filename, fopen_for_read);
	if (p == NULL) {
		rc = FALSE;
		goto error;
	}

	while (config_read(p, tokens, 3, 2, "# \t", PARSE_NORMAL)) {
//Use index_in_strings?
		if (strcmp(tokens[0], "alias") == 0) {
			/* alias <wildcard> <modulename> */
			llist_t *l;
			char wildcard[MODULE_NAME_LEN];
			char *rmod;

			if (tokens[2] == NULL)
				continue;
			filename2modname(tokens[1], wildcard);

			for (l = G.probes; l != NULL; l = l->link) {
				m = (struct module_entry *) l->data;
				if (fnmatch(wildcard, m->modname, 0) != 0)
					continue;
				rmod = filename2modname(tokens[2], NULL);
				llist_add_to(&m->realnames, rmod);

				if (m->flags & MODULE_FLAG_NEED_DEPS) {
					m->flags &= ~MODULE_FLAG_NEED_DEPS;
					G.num_unresolved_deps--;
				}

				m = get_or_add_modentry(rmod);
				if (!(m->flags & MODULE_FLAG_NEED_DEPS)) {
					m->flags |= MODULE_FLAG_NEED_DEPS;
					G.num_unresolved_deps++;
				}
			}
		} else if (strcmp(tokens[0], "options") == 0) {
			/* options <modulename> <option...> */
			if (tokens[2] == NULL)
				continue;
			m = get_or_add_modentry(tokens[1]);
			m->options = gather_options_str(m->options, tokens[2]);
		} else if (strcmp(tokens[0], "include") == 0) {
			/* include <filename> */
			read_config(tokens[1]);
		} else if (ENABLE_FEATURE_MODPROBE_BLACKLIST
		 && strcmp(tokens[0], "blacklist") == 0
		) {
			/* blacklist <modulename> */
			get_or_add_modentry(tokens[1])->flags |= MODULE_FLAG_BLACKLISTED;
		}
	}
	config_close(p);
 error:
	return rc;
}

static int read_config(const char *path)
{
	return recursive_action(path, ACTION_RECURSE | ACTION_QUIET,
				config_file_action, NULL, NULL, 1);
}

static const char *humanly_readable_name(struct module_entry *m)
{
	/* probed_name may be NULL. modname always exists. */
	return m->probed_name ? m->probed_name : m->modname;
}

static char *parse_and_add_kcmdline_module_options(char *options, const char *modulename)
{
	char *kcmdline_buf;
	char *kcmdline;
	char *kptr;
	int len;

	kcmdline_buf = xmalloc_open_read_close("/proc/cmdline", NULL);
	if (!kcmdline_buf)
		return options;

	kcmdline = kcmdline_buf;
	len = strlen(modulename);
	while ((kptr = strsep(&kcmdline, "\n\t ")) != NULL) {
		if (strncmp(modulename, kptr, len) != 0)
			continue;
		kptr += len;
		if (*kptr != '.')
			continue;
		/* It is "modulename.xxxx" */
		kptr++;
		if (strchr(kptr, '=') != NULL) {
			/* It is "modulename.opt=[val]" */
			options = gather_options_str(options, kptr);
		}
	}
	free(kcmdline_buf);

	return options;
}

/* Return: similar to bb_init_module:
 * 0 on success,
 * -errno on open/read error,
 * errno on init_module() error
 */
/* NB: INSMOD_OPT_SILENT bit suppresses ONLY non-existent modules,
 * not deleted ones (those are still listed in modules.dep).
 * module-init-tools version 3.4:
 * # modprobe bogus
 * FATAL: Module bogus not found. [exitcode 1]
 * # modprobe -q bogus            [silent, exitcode still 1]
 * but:
 * # rm kernel/drivers/net/dummy.ko
 * # modprobe -q dummy
 * FATAL: Could not open '/lib/modules/xxx/kernel/drivers/net/dummy.ko': No such file or directory
 * [exitcode 1]
 */
static int do_modprobe(struct module_entry *m)
{
	struct module_entry *m2 = m2; /* for compiler */
	char *fn, *options;
	int rc, first;
	llist_t *l;

	if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
		if (!(option_mask32 & INSMOD_OPT_SILENT))
			bb_error_msg("module %s not found in modules.dep",
				humanly_readable_name(m));
		return -ENOENT;
	}
	DBG("do_modprob'ing %s", m->modname);

	if (!(option_mask32 & MODPROBE_OPT_REMOVE))
		m->deps = llist_rev(m->deps);

	for (l = m->deps; l != NULL; l = l->link)
		DBG("dep: %s", l->data);

	first = 1;
	rc = 0;
	while (m->deps) {
		rc = 0;
		fn = llist_pop(&m->deps); /* we leak it */
		m2 = get_or_add_modentry(fn);

		if (option_mask32 & MODPROBE_OPT_REMOVE) {
			/* modprobe -r */
			if (m2->flags & MODULE_FLAG_LOADED) {
				rc = bb_delete_module(m2->modname, O_EXCL);
				if (rc) {
					if (first) {
						bb_error_msg("can't unload module %s: %s",
							humanly_readable_name(m2),
							moderror(rc));
						break;
					}
				} else {
					m2->flags &= ~MODULE_FLAG_LOADED;
				}
			}
			/* do not error out if *deps* fail to unload */
			first = 0;
			continue;
		}

		if (m2->flags & MODULE_FLAG_LOADED) {
			DBG("%s is already loaded, skipping", fn);
			continue;
		}

		options = m2->options;
		m2->options = NULL;
		options = parse_and_add_kcmdline_module_options(options, m2->modname);
		if (m == m2)
			options = gather_options_str(options, G.cmdline_mopts);
		rc = bb_init_module(fn, options);
		DBG("loaded %s '%s', rc:%d", fn, options, rc);
		if (rc == EEXIST)
			rc = 0;
		free(options);
		if (rc) {
			bb_error_msg("can't load module %s (%s): %s",
				humanly_readable_name(m2),
				fn,
				moderror(rc)
			);
			break;
		}
		m2->flags |= MODULE_FLAG_LOADED;
	}

	return rc;
}

static void load_modules_dep(void)
{
	struct module_entry *m;
	char *colon, *tokens[2];
	parser_t *p;

	/* Modprobe does not work at all without modules.dep,
	 * even if the full module name is given. Returning error here
	 * was making us later confuse user with this message:
	 * "module /full/path/to/existing/file/module.ko not found".
	 * It's better to die immediately, with good message.
	 * xfopen_for_read provides that. */
	p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);

	while (G.num_unresolved_deps
	 && config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)
	) {
		colon = last_char_is(tokens[0], ':');
		if (colon == NULL)
			continue;
		*colon = 0;

		m = get_modentry(tokens[0]);
		if (m == NULL)
			continue;

		/* Optimization... */
		if ((m->flags & MODULE_FLAG_LOADED)
		 && !(option_mask32 & MODPROBE_OPT_REMOVE)
		) {
			DBG("skip deps of %s, it's already loaded", tokens[0]);
			continue;
		}

		m->flags |= MODULE_FLAG_FOUND_IN_MODDEP;
		if ((m->flags & MODULE_FLAG_NEED_DEPS) && (m->deps == NULL)) {
			G.num_unresolved_deps--;
			llist_add_to(&m->deps, xstrdup(tokens[0]));
			if (tokens[1])
				string_to_llist(tokens[1], &m->deps, " \t");
		} else
			DBG("skipping dep line");
	}
	config_close(p);
}

int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int modprobe_main(int argc UNUSED_PARAM, char **argv)
{
	struct utsname uts;
	int rc;
	unsigned opt;
	struct module_entry *me;

	opt_complementary = MODPROBE_COMPLEMENTARY;
	opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS);
	argv += optind;

	/* Goto modules location */
	xchdir(CONFIG_DEFAULT_MODULES_DIR);
	uname(&uts);
	xchdir(uts.release);

	if (opt & MODPROBE_OPT_LIST_ONLY) {
		char name[MODULE_NAME_LEN];
		char *colon, *tokens[2];
		parser_t *p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);

		while (config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)) {
			colon = last_char_is(tokens[0], ':');
			if (!colon)
				continue;
			*colon = '\0';
			filename2modname(tokens[0], name);
			if (!argv[0])
				puts(tokens[0]);
			else {
				int i;
				for (i = 0; argv[i]; i++) {
					if (fnmatch(argv[i], name, 0) == 0) {
						puts(tokens[0]);
					}
				}
			}
		}
		return EXIT_SUCCESS;
	}

	/* Yes, for some reason -l ignores -s... */
	if (opt & INSMOD_OPT_SYSLOG)
		logmode = LOGMODE_SYSLOG;

	if (!argv[0]) {
		if (opt & MODPROBE_OPT_REMOVE) {
			/* "modprobe -r" (w/o params).
			 * "If name is NULL, all unused modules marked
			 * autoclean will be removed".
			 */
			if (bb_delete_module(NULL, O_NONBLOCK | O_EXCL) != 0)
				bb_perror_msg_and_die("rmmod");
		}
		return EXIT_SUCCESS;
	}

	/* Retrieve module names of already loaded modules */
	{
		char *s;
		parser_t *parser = config_open2("/proc/modules", fopen_for_read);
		while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY))
			get_or_add_modentry(s)->flags |= MODULE_FLAG_LOADED;
		config_close(parser);
	}

	if (opt & (MODPROBE_OPT_INSERT_ALL | MODPROBE_OPT_REMOVE)) {
		/* Each argument is a module name */
		do {
			DBG("adding module %s", *argv);
			add_probe(*argv++);
		} while (*argv);
	} else {
		/* First argument is module name, rest are parameters */
		DBG("probing just module %s", *argv);
		add_probe(argv[0]);
		G.cmdline_mopts = parse_cmdline_module_options(argv);
	}

	/* Happens if all requested modules are already loaded */
	if (G.probes == NULL)
		return EXIT_SUCCESS;

	read_config("/etc/modprobe.conf");
	read_config("/etc/modprobe.d");
	if (ENABLE_FEATURE_MODUTILS_SYMBOLS && G.need_symbols)
		read_config("modules.symbols");
	load_modules_dep();
	if (ENABLE_FEATURE_MODUTILS_ALIAS && G.num_unresolved_deps) {
		read_config("modules.alias");
		load_modules_dep();
	}

	rc = 0;
	while ((me = llist_pop(&G.probes)) != NULL) {
		if (me->realnames == NULL) {
			DBG("probing by module name");
			/* This is not an alias. Literal names are blacklisted
			 * only if '-b' is given.
			 */
			if (!(opt & MODPROBE_OPT_BLACKLIST)
			 || !(me->flags & MODULE_FLAG_BLACKLISTED)
			) {
				rc |= do_modprobe(me);
			}
			continue;
		}

		/* Probe all real names for the alias */
		do {
			char *realname = llist_pop(&me->realnames);
			struct module_entry *m2;

			DBG("probing alias %s by realname %s", me->modname, realname);
			m2 = get_or_add_modentry(realname);
			if (!(m2->flags & MODULE_FLAG_BLACKLISTED)
			 && (!(m2->flags & MODULE_FLAG_LOADED)
			    || (opt & MODPROBE_OPT_REMOVE))
			) {
//TODO: we can pass "me" as 2nd param to do_modprobe,
//and make do_modprobe emit more meaningful error messages
//with alias name included, not just module name alias resolves to.
				rc |= do_modprobe(m2);
			}
			free(realname);
		} while (me->realnames != NULL);
	}

	return (rc != 0);
}