LKML Archive on
help / color / mirror / Atom feed
From: Richard Hacker <>
Subject: [PATCH 001/002] scripts/mod/modpost.c: New option -E to load extra symbols
Date: Thu, 28 Feb 2008 09:40:52 +0100	[thread overview]
Message-ID: <> (raw)

This patch adds a new command line option -E to modpost, expecting a symbol
file as an argument which is read prior to symbol processing. -E can be 
supplied multiple times for as many files as is needed.

Signed-off-by: Richard Hacker <>

When building kernel modules that depend on other modules not in the main 
kernel tree, modpost complains about undefined symbols:
# make -C /path/to/linux/kernel M=/path/to/my/module
Building modules, stage 2.
WARNING: "rt_copy_buf" [/home/rich/osc_etl_rtw/osc_kmod.ko] undefined!

This situation occurs when modpost processes the new module's symbols. When
it finds symbols not exported by the mainline kernel, it issues this warning.

The patch adds a new command line option -E to modpost which expects a symbol
file as an argument. The symbols listed in this file are added to modpost's
symbol tables during startup. -E can be supplied as often as required.

This patch works together with the second patch. It introduces a new make
variable, EXTRA_SYMBOLS, which is used when calling modpost.

I hope this patch is useful and finds its way into the kernel.

o Changes from the previous attempt:
   - patches kernel version 2.6.24
   - patches for scripts/mod/modpost.c and scripts/Makefile.modpost are 
   - the argument to -E is now a single file, not a comma separated list 
     any more. To pass more than one file, -E is used as often as required
   - patch 002/002 in this series introduces the Kbuild variable EXTRA_SYMBOLS
     to scripts/Makefile.modpost that in turn calls modpost with the correct
     -E command line arguments.

--- linux-2.6.24-vanilla/scripts/mod/modpost.c	2008-02-27 21:10:24.000000000 
+++ linux-2.6.24/scripts/mod/modpost.c	2008-02-27 21:14:36.000000000 +0100
@@ -1658,8 +1658,12 @@ int main(int argc, char **argv)
 	char *dump_write = NULL;
 	int opt;
 	int err;
+	struct ext_sym_list {
+		struct ext_sym_list *next;
+		const char *file;
+	} *extsym_start = NULL, *extsym_iter;
-	while ((opt = getopt(argc, argv, "i:I:mso:aw")) != -1) {
+	while ((opt = getopt(argc, argv, "i:I:E:mso:aw")) != -1) {
 		switch(opt) {
 			case 'i':
 				kernel_read = optarg;
@@ -1668,6 +1672,14 @@ int main(int argc, char **argv)
 				module_read = optarg;
 				external_module = 1;
+			case 'E':
+				external_module = 1;
+				extsym_iter =
+					NOFAIL(malloc(sizeof(*extsym_iter)));
+				extsym_iter->next = extsym_start;
+				extsym_iter->file = optarg;
+				extsym_start = extsym_iter;
+				break;
 			case 'm':
 				modversions = 1;
@@ -1692,6 +1704,12 @@ int main(int argc, char **argv)
 		read_dump(kernel_read, 1);
 	if (module_read)
 		read_dump(module_read, 0);
+	while (extsym_start) {
+		read_dump(extsym_start->file, 0);
+		extsym_iter = extsym_start->next;
+		free(extsym_start);
+		extsym_start = extsym_iter;
+	}
 	while (optind < argc) {

             reply	other threads:[~2008-02-28  8:40 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-28  8:40 Richard Hacker [this message]
2008-02-28  9:18 ` Sam Ravnborg
2008-02-28 10:42   ` Richard Hacker
2008-04-25 18:57 ` Sam Ravnborg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \
    --subject='Re: [PATCH 001/002] scripts/mod/modpost.c: New option -E to load extra symbols' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).