示例#1
0
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
	struct dwarf_callback_param *param = data;

	param->retval = find_line_range_by_line(in_die, param->data);
	return DWARF_CB_ABORT;	/* No need to find other instances */
}
static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
{
	struct dwarf_callback_param *param = data;
	struct line_finder *lf = param->data;
	struct line_range *lr = lf->lr;

	
	if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
		return DWARF_CB_OK;

	if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
	    die_compare_name(sp_die, lr->function)) {
		lf->fname = dwarf_decl_file(sp_die);
		dwarf_decl_line(sp_die, &lr->offset);
		pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
		lf->lno_s = lr->offset + lr->start;
		if (lf->lno_s < 0)	
			lf->lno_s = INT_MAX;
		lf->lno_e = lr->offset + lr->end;
		if (lf->lno_e < 0)	
			lf->lno_e = INT_MAX;
		pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
		lr->start = lf->lno_s;
		lr->end = lf->lno_e;
		if (dwarf_func_inline(sp_die))
			param->retval = die_walk_instances(sp_die,
						line_range_inline_cb, lf);
		else
			param->retval = find_line_range_by_line(sp_die, lf);
		return DWARF_CB_ABORT;
	}
	return DWARF_CB_OK;
}
示例#3
0
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
	find_line_range_by_line(in_die, data);

	/*
	 * We have to check all instances of inlined function, because
	 * some execution paths can be optimized out depends on the
	 * function argument of instances
	 */
	return 0;
}
示例#4
0
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
	int ret = find_line_range_by_line(in_die, data);

	/*
	 * We have to check all instances of inlined function, because
	 * some execution paths can be optimized out depends on the
	 * function argument of instances. However, if an error occurs,
	 * it should be handled by the caller.
	 */
	return ret < 0 ? ret : 0;
}
static int find_line_range_by_func(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
	return param.retval;
}

int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
{
	struct line_finder lf = {.lr = lr, .found = 0};
	int ret = 0;
	Dwarf_Off off = 0, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	const char *comp_dir;

	
	if (lr->function) {
		struct pubname_callback_param pubname_param = {
			.function = lr->function, .file = lr->file,
			.cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
		struct dwarf_callback_param line_range_param = {
			.data = (void *)&lf, .retval = 0};

		dwarf_getpubnames(self->dbg, pubname_search_cb,
				  &pubname_param, 0);
		if (pubname_param.found) {
			line_range_search_cb(&lf.sp_die, &line_range_param);
			if (lf.found)
				goto found;
		}
	}

	
	while (!lf.found && ret >= 0) {
		if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
				 NULL, NULL, NULL) != 0)
			break;

		
		diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
		if (!diep)
			continue;

		
		if (lr->file)
			lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
		else
			lf.fname = 0;

		if (!lr->file || lf.fname) {
			if (lr->function)
				ret = find_line_range_by_func(&lf);
			else {
				lf.lno_s = lr->start;
				lf.lno_e = lr->end;
				ret = find_line_range_by_line(NULL, &lf);
			}
		}
		off = noff;
	}

found:
	
	if (lf.found) {
		comp_dir = cu_get_comp_dir(&lf.cu_die);
		if (comp_dir) {
			lr->comp_dir = strdup(comp_dir);
			if (!lr->comp_dir)
				ret = -ENOMEM;
		}
	}

	pr_debug("path: %s\n", lr->path);
	return (ret < 0) ? ret : lf.found;
}
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
	find_line_range_by_line(in_die, data);

	return 0;
}
示例#7
0
static int find_line_range_by_func(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
	return param.retval;
}

int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
{
	struct line_finder lf = {.lr = lr, .found = 0};
	int ret = 0;
	Dwarf_Off off = 0, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	const char *comp_dir;

	/* Fastpath: lookup by function name from .debug_pubnames section */
	if (lr->function) {
		struct pubname_callback_param pubname_param = {
			.function = lr->function, .file = lr->file,
			.cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
		struct dwarf_callback_param line_range_param = {
			.data = (void *)&lf, .retval = 0};

		dwarf_getpubnames(dbg->dbg, pubname_search_cb,
				  &pubname_param, 0);
		if (pubname_param.found) {
			line_range_search_cb(&lf.sp_die, &line_range_param);
			if (lf.found)
				goto found;
		}
	}

	/* Loop on CUs (Compilation Unit) */
	while (!lf.found && ret >= 0) {
		if (dwarf_nextcu(dbg->dbg, off, &noff, &cuhl,
				 NULL, NULL, NULL) != 0)
			break;

		/* Get the DIE(Debugging Information Entry) of this CU */
		diep = dwarf_offdie(dbg->dbg, off + cuhl, &lf.cu_die);
		if (!diep)
			continue;

		/* Check if target file is included. */
		if (lr->file)
			lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
		else
			lf.fname = 0;

		if (!lr->file || lf.fname) {
			if (lr->function)
				ret = find_line_range_by_func(&lf);
			else {
				lf.lno_s = lr->start;
				lf.lno_e = lr->end;
				ret = find_line_range_by_line(NULL, &lf);
			}
		}
		off = noff;
	}

found:
	/* Store comp_dir */
	if (lf.found) {
		comp_dir = cu_get_comp_dir(&lf.cu_die);
		if (comp_dir) {
			lr->comp_dir = strdup(comp_dir);
			if (!lr->comp_dir)
				ret = -ENOMEM;
		}
	}

	pr_debug("path: %s\n", lr->path);
	return (ret < 0) ? ret : lf.found;
}

/*
 * Find a src file from a DWARF tag path. Prepend optional source path prefix
 * and chop off leading directories that do not exist. Result is passed back as
 * a newly allocated path on success.
 * Return 0 if file was found and readable, -errno otherwise.
 */
int get_real_path(const char *raw_path, const char *comp_dir,
			 char **new_path)
{
	const char *prefix = symbol_conf.source_prefix;

	if (!prefix) {
		if (raw_path[0] != '/' && comp_dir)
			/* If not an absolute path, try to use comp_dir */
			prefix = comp_dir;
		else {
			if (access(raw_path, R_OK) == 0) {
				*new_path = strdup(raw_path);
				return *new_path ? 0 : -ENOMEM;
			} else
				return -errno;
		}
	}

	*new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
	if (!*new_path)
		return -ENOMEM;

	for (;;) {
		sprintf(*new_path, "%s/%s", prefix, raw_path);

		if (access(*new_path, R_OK) == 0)
			return 0;

		if (!symbol_conf.source_prefix) {
			/* In case of searching comp_dir, don't retry */
			zfree(new_path);
			return -errno;
		}

		switch (errno) {
		case ENAMETOOLONG:
		case ENOENT:
		case EROFS:
		case EFAULT:
			raw_path = strchr(++raw_path, '/');
			if (!raw_path) {
				zfree(new_path);
				return -ENOENT;
			}
			continue;

		default:
			zfree(new_path);
			return -errno;
		}
	}
}
示例#8
0
static int find_line_range_by_func(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
	return param.retval;
}

int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
{
	struct line_finder lf = {.lr = lr, .found = 0};
	int ret = 0;
	Dwarf_Off off = 0, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	const char *comp_dir;

	/* Fastpath: lookup by function name from .debug_pubnames section */
	if (lr->function) {
		struct pubname_callback_param pubname_param = {
			.function = lr->function, .file = lr->file,
			.cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
		struct dwarf_callback_param line_range_param = {
			.data = (void *)&lf, .retval = 0};

		dwarf_getpubnames(self->dbg, pubname_search_cb,
				  &pubname_param, 0);
		if (pubname_param.found) {
			line_range_search_cb(&lf.sp_die, &line_range_param);
			if (lf.found)
				goto found;
		}
	}

	/* Loop on CUs (Compilation Unit) */
	while (!lf.found && ret >= 0) {
		if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
				 NULL, NULL, NULL) != 0)
			break;

		/* Get the DIE(Debugging Information Entry) of this CU */
		diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
		if (!diep)
			continue;

		/* Check if target file is included. */
		if (lr->file)
			lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
		else
			lf.fname = 0;

		if (!lr->file || lf.fname) {
			if (lr->function)
				ret = find_line_range_by_func(&lf);
			else {
				lf.lno_s = lr->start;
				lf.lno_e = lr->end;
				ret = find_line_range_by_line(NULL, &lf);
			}
		}
		off = noff;
	}

found:
	/* Store comp_dir */
	if (lf.found) {
		comp_dir = cu_get_comp_dir(&lf.cu_die);
		if (comp_dir) {
			lr->comp_dir = strdup(comp_dir);
			if (!lr->comp_dir)
				ret = -ENOMEM;
		}
	}

	pr_debug("path: %s\n", lr->path);
	return (ret < 0) ? ret : lf.found;
}
示例#9
0
/* Search function from function name */
static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
{
	struct dwarf_callback_param *param = data;
	struct probe_finder *pf = param->data;
	struct perf_probe_point *pp = &pf->pev->point;

	/* Check tag and diename */
	if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
	    die_compare_name(sp_die, pp->function) != 0)
		return DWARF_CB_OK;

	pf->fname = dwarf_decl_file(sp_die);
	if (pp->line) { /* Function relative line */
		dwarf_decl_line(sp_die, &pf->lno);
		pf->lno += pp->line;
		param->retval = find_probe_point_by_line(pf);
	} else if (!dwarf_func_inline(sp_die)) {
		/* Real function */
		if (pp->lazy_line)
			param->retval = find_probe_point_lazy(sp_die, pf);
		else {
			if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
				pr_warning("Failed to get entry pc of %s.\n",
					   dwarf_diename(sp_die));
				param->retval = -ENOENT;
				return DWARF_CB_ABORT;
			}
			pf->addr += pp->offset;
			/* TODO: Check the address in this function */
			param->retval = convert_probe_point(sp_die, pf);
		}
	} else {
		struct dwarf_callback_param _param = {.data = (void *)pf,
						      .retval = 0};
		/* Inlined function: search instances */
		dwarf_func_inline_instances(sp_die, probe_point_inline_cb,
					    &_param);
		param->retval = _param.retval;
	}

	return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
}

static int find_probe_point_by_func(struct probe_finder *pf)
{
	struct dwarf_callback_param _param = {.data = (void *)pf,
					      .retval = 0};
	dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
	return _param.retval;
}

/* Find kprobe_trace_events specified by perf_probe_event from debuginfo */
int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
			     struct kprobe_trace_event **tevs, int max_tevs)
{
	struct probe_finder pf = {.pev = pev, .max_tevs = max_tevs};
	struct perf_probe_point *pp = &pev->point;
	Dwarf_Off off, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	Dwarf *dbg;
	int ret = 0;

	pf.tevs = zalloc(sizeof(struct kprobe_trace_event) * max_tevs);
	if (pf.tevs == NULL)
		return -ENOMEM;
	*tevs = pf.tevs;
	pf.ntevs = 0;

	dbg = dwarf_begin(fd, DWARF_C_READ);
	if (!dbg) {
		pr_warning("No dwarf info found in the vmlinux - "
			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
		free(pf.tevs);
		*tevs = NULL;
		return -EBADF;
	}

#if _ELFUTILS_PREREQ(0, 142)
	/* Get the call frame information from this dwarf */
	pf.cfi = dwarf_getcfi(dbg);
#endif

	off = 0;
	line_list__init(&pf.lcache);
	/* Loop on CUs (Compilation Unit) */
	while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) &&
	       ret >= 0) {
		/* Get the DIE(Debugging Information Entry) of this CU */
		diep = dwarf_offdie(dbg, off + cuhl, &pf.cu_die);
		if (!diep)
			continue;

		/* Check if target file is included. */
		if (pp->file)
			pf.fname = cu_find_realpath(&pf.cu_die, pp->file);
		else
			pf.fname = NULL;

		if (!pp->file || pf.fname) {
			if (pp->function)
				ret = find_probe_point_by_func(&pf);
			else if (pp->lazy_line)
				ret = find_probe_point_lazy(NULL, &pf);
			else {
				pf.lno = pp->line;
				ret = find_probe_point_by_line(&pf);
			}
		}
		off = noff;
	}
	line_list__free(&pf.lcache);
	dwarf_end(dbg);

	return (ret < 0) ? ret : pf.ntevs;
}

/* Reverse search */
int find_perf_probe_point(int fd, unsigned long addr,
			  struct perf_probe_point *ppt)
{
	Dwarf_Die cudie, spdie, indie;
	Dwarf *dbg;
	Dwarf_Line *line;
	Dwarf_Addr laddr, eaddr;
	const char *tmp;
	int lineno, ret = 0;
	bool found = false;

	dbg = dwarf_begin(fd, DWARF_C_READ);
	if (!dbg)
		return -EBADF;

	/* Find cu die */
	if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie)) {
		ret = -EINVAL;
		goto end;
	}

	/* Find a corresponding line */
	line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr);
	if (line) {
		if (dwarf_lineaddr(line, &laddr) == 0 &&
		    (Dwarf_Addr)addr == laddr &&
		    dwarf_lineno(line, &lineno) == 0) {
			tmp = dwarf_linesrc(line, NULL, NULL);
			if (tmp) {
				ppt->line = lineno;
				ppt->file = strdup(tmp);
				if (ppt->file == NULL) {
					ret = -ENOMEM;
					goto end;
				}
				found = true;
			}
		}
	}

	/* Find a corresponding function */
	if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {
		tmp = dwarf_diename(&spdie);
		if (!tmp || dwarf_entrypc(&spdie, &eaddr) != 0)
			goto end;

		if (ppt->line) {
			if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
						&indie)) {
				/* addr in an inline function */
				tmp = dwarf_diename(&indie);
				if (!tmp)
					goto end;
				ret = dwarf_decl_line(&indie, &lineno);
			} else {
				if (eaddr == addr) {	/* Function entry */
					lineno = ppt->line;
					ret = 0;
				} else
					ret = dwarf_decl_line(&spdie, &lineno);
			}
			if (ret == 0) {
				/* Make a relative line number */
				ppt->line -= lineno;
				goto found;
			}
		}
		/* We don't have a line number, let's use offset */
		ppt->offset = addr - (unsigned long)eaddr;
found:
		ppt->function = strdup(tmp);
		if (ppt->function == NULL) {
			ret = -ENOMEM;
			goto end;
		}
		found = true;
	}

end:
	dwarf_end(dbg);
	if (ret >= 0)
		ret = found ? 1 : 0;
	return ret;
}

/* Add a line and store the src path */
static int line_range_add_line(const char *src, unsigned int lineno,
			       struct line_range *lr)
{
	/* Copy real path */
	if (!lr->path) {
		lr->path = strdup(src);
		if (lr->path == NULL)
			return -ENOMEM;
	}
	return line_list__add_line(&lr->line_list, lineno);
}

/* Search function declaration lines */
static int line_range_funcdecl_cb(Dwarf_Die *sp_die, void *data)
{
	struct dwarf_callback_param *param = data;
	struct line_finder *lf = param->data;
	const char *src;
	int lineno;

	src = dwarf_decl_file(sp_die);
	if (src && strtailcmp(src, lf->fname) != 0)
		return DWARF_CB_OK;

	if (dwarf_decl_line(sp_die, &lineno) != 0 ||
	    (lf->lno_s > lineno || lf->lno_e < lineno))
		return DWARF_CB_OK;

	param->retval = line_range_add_line(src, lineno, lf->lr);
	if (param->retval < 0)
		return DWARF_CB_ABORT;
	return DWARF_CB_OK;
}

static int find_line_range_func_decl_lines(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_funcdecl_cb, &param, 0);
	return param.retval;
}

/* Find line range from its line number */
static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
{
	Dwarf_Lines *lines;
	Dwarf_Line *line;
	size_t nlines, i;
	Dwarf_Addr addr;
	int lineno, ret = 0;
	const char *src;
	Dwarf_Die die_mem;

	line_list__init(&lf->lr->line_list);
	if (dwarf_getsrclines(&lf->cu_die, &lines, &nlines) != 0) {
		pr_warning("No source lines found in this CU.\n");
		return -ENOENT;
	}

	/* Search probable lines on lines list */
	for (i = 0; i < nlines; i++) {
		line = dwarf_onesrcline(lines, i);
		if (dwarf_lineno(line, &lineno) != 0 ||
		    (lf->lno_s > lineno || lf->lno_e < lineno))
			continue;

		if (sp_die) {
			/* Address filtering 1: does sp_die include addr? */
			if (dwarf_lineaddr(line, &addr) != 0 ||
			    !dwarf_haspc(sp_die, addr))
				continue;

			/* Address filtering 2: No child include addr? */
			if (die_find_inlinefunc(sp_die, addr, &die_mem))
				continue;
		}

		/* TODO: Get fileno from line, but how? */
		src = dwarf_linesrc(line, NULL, NULL);
		if (strtailcmp(src, lf->fname) != 0)
			continue;

		ret = line_range_add_line(src, lineno, lf->lr);
		if (ret < 0)
			return ret;
	}

	/*
	 * Dwarf lines doesn't include function declarations. We have to
	 * check functions list or given function.
	 */
	if (sp_die) {
		src = dwarf_decl_file(sp_die);
		if (src && dwarf_decl_line(sp_die, &lineno) == 0 &&
		    (lf->lno_s <= lineno && lf->lno_e >= lineno))
			ret = line_range_add_line(src, lineno, lf->lr);
	} else
		ret = find_line_range_func_decl_lines(lf);

	/* Update status */
	if (ret >= 0)
		if (!list_empty(&lf->lr->line_list))
			ret = lf->found = 1;
		else
			ret = 0;	/* Lines are not found */
	else {
		free(lf->lr->path);
		lf->lr->path = NULL;
	}
	return ret;
}

static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
	struct dwarf_callback_param *param = data;

	param->retval = find_line_range_by_line(in_die, param->data);
	return DWARF_CB_ABORT;	/* No need to find other instances */
}

/* Search function from function name */
static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
{
	struct dwarf_callback_param *param = data;
	struct line_finder *lf = param->data;
	struct line_range *lr = lf->lr;

	if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
	    die_compare_name(sp_die, lr->function) == 0) {
		lf->fname = dwarf_decl_file(sp_die);
		dwarf_decl_line(sp_die, &lr->offset);
		pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
		lf->lno_s = lr->offset + lr->start;
		if (lf->lno_s < 0)	/* Overflow */
			lf->lno_s = INT_MAX;
		lf->lno_e = lr->offset + lr->end;
		if (lf->lno_e < 0)	/* Overflow */
			lf->lno_e = INT_MAX;
		pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
		lr->start = lf->lno_s;
		lr->end = lf->lno_e;
		if (dwarf_func_inline(sp_die)) {
			struct dwarf_callback_param _param;
			_param.data = (void *)lf;
			_param.retval = 0;
			dwarf_func_inline_instances(sp_die,
						    line_range_inline_cb,
						    &_param);
			param->retval = _param.retval;
		} else
			param->retval = find_line_range_by_line(sp_die, lf);
		return DWARF_CB_ABORT;
	}
	return DWARF_CB_OK;
}

static int find_line_range_by_func(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
	return param.retval;
}

int find_line_range(int fd, struct line_range *lr)
{
	struct line_finder lf = {.lr = lr, .found = 0};
	int ret = 0;
	Dwarf_Off off = 0, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	Dwarf *dbg;

	dbg = dwarf_begin(fd, DWARF_C_READ);
	if (!dbg) {
		pr_warning("No dwarf info found in the vmlinux - "
			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
		return -EBADF;
	}

	/* Loop on CUs (Compilation Unit) */
	while (!lf.found && ret >= 0) {
		if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0)
			break;

		/* Get the DIE(Debugging Information Entry) of this CU */
		diep = dwarf_offdie(dbg, off + cuhl, &lf.cu_die);
		if (!diep)
			continue;

		/* Check if target file is included. */
		if (lr->file)
			lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
		else
			lf.fname = 0;

		if (!lr->file || lf.fname) {
			if (lr->function)
				ret = find_line_range_by_func(&lf);
			else {
				lf.lno_s = lr->start;
				lf.lno_e = lr->end;
				ret = find_line_range_by_line(NULL, &lf);
			}
		}
		off = noff;
	}
	pr_debug("path: %lx\n", (unsigned long)lr->path);
	dwarf_end(dbg);

	return (ret < 0) ? ret : lf.found;
}
示例#10
0
static int find_line_range_by_func(struct line_finder *lf)
{
	struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
	dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
	return param.retval;
}

int find_line_range(int fd, struct line_range *lr)
{
	struct line_finder lf = {.lr = lr, .found = 0};
	int ret = 0;
	Dwarf_Off off = 0, noff;
	size_t cuhl;
	Dwarf_Die *diep;
	Dwarf *dbg = NULL;
	Dwfl *dwfl;
	Dwarf_Addr bias;	/* Currently ignored */
	const char *comp_dir;

	dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias);
	if (!dbg) {
		pr_warning("No debug information found in the vmlinux - "
			"please rebuild with CONFIG_DEBUG_INFO=y.\n");
		return -EBADF;
	}

	/* Loop on CUs (Compilation Unit) */
	while (!lf.found && ret >= 0) {
		if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0)
			break;

		/* Get the DIE(Debugging Information Entry) of this CU */
		diep = dwarf_offdie(dbg, off + cuhl, &lf.cu_die);
		if (!diep)
			continue;

		/* Check if target file is included. */
		if (lr->file)
			lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
		else
			lf.fname = 0;

		if (!lr->file || lf.fname) {
			if (lr->function)
				ret = find_line_range_by_func(&lf);
			else {
				lf.lno_s = lr->start;
				lf.lno_e = lr->end;
				ret = find_line_range_by_line(NULL, &lf);
			}
		}
		off = noff;
	}

	/* Store comp_dir */
	if (lf.found) {
		comp_dir = cu_get_comp_dir(&lf.cu_die);
		if (comp_dir) {
			lr->comp_dir = strdup(comp_dir);
			if (!lr->comp_dir)
				ret = -ENOMEM;
		}
	}

	pr_debug("path: %s\n", lr->path);
	dwfl_end(dwfl);
	return (ret < 0) ? ret : lf.found;
}