File module-options-from-kernel-cmdline.patch of Package module-init-tools

commit 83a882728ee10282682e38c7f42007f465dd3361
Author: Jon Masters <jcm@jcmlaptop.bos.redhat.com>
Date:   Tue Sep 9 11:40:15 2008 -0400

    It is often advantageous to pass parameters to built-in kernel modules
    at boot time using the convention <module>.<option>. However, this does
    not work with loadable modules where modprobe reads its options from the
    config files. This patch adds support for modprobe to read /proc/cmdline
    and add any options it finds when inserting the modules.
    
    Signed-off-by: Dan Nicholson <dbn.lists@gmail.com>
    Signed-off-by: Jon Masters <jcm@jonmasters.org>

diff --git a/doc/modprobe.sgml b/doc/modprobe.sgml
index 767582a..3c63004 100644
--- a/doc/modprobe.sgml
+++ b/doc/modprobe.sgml
@@ -77,7 +77,9 @@
       <filename>/etc/modprobe.d</filename> directory
       (see <citerefentry>
 	<refentrytitle>modprobe.conf</refentrytitle><manvolnum>5</manvolnum>
-      </citerefentry>).
+      </citerefentry>). <command>modprobe</command> will also use module
+      options specified on the kernel command line in the form of
+      &lt;module&gt;.option&gt;.
     </para>
     <para>
       Note that this version of <command>modprobe</command> does not
diff --git a/modprobe.c b/modprobe.c
index 9b171cc..51b9d64 100644
--- a/modprobe.c
+++ b/modprobe.c
@@ -1257,6 +1257,46 @@ static void read_toplevel_config(const char *filename,
 	}
 }
 
+/* Read possible module arguments from the kernel command line. */
+static int read_kcmdline(int dump_only, struct module_options **options)
+{
+	char *line;
+	unsigned int linenum = 0;
+	FILE *kcmdline;
+
+	kcmdline = fopen("/proc/cmdline", "r");
+	if (!kcmdline)
+		return 0;
+
+	while ((line = getline_wrapped(kcmdline, &linenum)) != NULL) {
+		char *ptr = line;
+		char *arg;
+
+		while ((arg = strsep_skipspace(&ptr, "\t ")) != NULL) {
+			char *sep, *modname, *opt;
+
+			sep = strchr(arg, '.');
+			if (sep) {
+				if (!strchr(sep, '='))
+					continue;
+				modname = arg;
+				*sep = '\0';
+				opt = ++sep;
+
+				if (dump_only)
+					printf("options %s %s\n", modname, opt);
+
+				*options = add_options(underscores(modname),
+						       opt, *options);
+			}
+		}
+
+		free(line);
+	}
+	fclose(kcmdline);
+	return 1;
+}
+
 static void add_to_env_var(const char *option)
 {
 	const char *oldenv;
@@ -1586,6 +1626,7 @@ int main(int argc, char *argv[])
 
 		read_toplevel_config(config, "", 1, 0,
 			     &modoptions, &commands, &aliases, &blacklist);
+		read_kcmdline(1, &modoptions);
 		read_config(aliasfilename, "", 1, 0,&modoptions, &commands,
 			    &aliases, &blacklist);
 		read_config(symfilename, "", 1, 0, &modoptions, &commands,
@@ -1617,6 +1658,9 @@ int main(int argc, char *argv[])
 		read_toplevel_config(config, modulearg, 0,
 		     remove, &modoptions, &commands, &aliases, &blacklist);
 
+		/* Read module options from kernel command line */
+		read_kcmdline(0, &modoptions);
+
 		/* No luck?  Try symbol names, if starts with symbol:. */
 		if (!aliases
 		    && strncmp(modulearg, "symbol:", strlen("symbol:")) == 0)