Commit 51e158c1 authored by Rusty Russell's avatar Rusty Russell
Browse files

param: hand arguments after -- straight to init



The kernel passes any args it doesn't need through to init, except it
assumes anything containing '.' belongs to the kernel (for a module).
This change means all users can clearly distinguish which arguments
are for init.

For example, the kernel uses debug ("dee-bug") to mean log everything to
the console, where systemd uses the debug from the Scandinavian "day-boog"
meaning "fail to boot".  If a future versions uses argv[] instead of
reading /proc/cmdline, this confusion will be avoided.

eg: test 'FOO="this is --foo"' -- 'systemd.debug="true true true"'

Gives:
argv[0] = '/debug-init'
argv[1] = 'test'
argv[2] = 'systemd.debug=true true true'
envp[0] = 'HOME=/'
envp[1] = 'TERM=linux'
envp[2] = 'FOO=this is --foo'

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent 2ee41e62
......@@ -321,7 +321,7 @@ extern bool parameq(const char *name1, const char *name2);
extern bool parameqn(const char *name1, const char *name2, size_t n);
/* Called on module insert or kernel boot */
extern int parse_args(const char *name,
extern char *parse_args(const char *name,
char *args,
const struct kernel_param *params,
unsigned num,
......
......@@ -252,6 +252,27 @@ static int __init repair_env_string(char *param, char *val, const char *unused)
return 0;
}
/* Anything after -- gets handed straight to init. */
static int __init set_init_arg(char *param, char *val, const char *unused)
{
unsigned int i;
if (panic_later)
return 0;
repair_env_string(param, val, unused);
for (i = 0; argv_init[i]; i++) {
if (i == MAX_INIT_ARGS) {
panic_later = "init";
panic_param = param;
return 0;
}
}
argv_init[i] = param;
return 0;
}
/*
* Unknown boot options get handed to init, unless they look like
* unused parameters (modprobe will find them in /proc/cmdline).
......@@ -478,7 +499,7 @@ static void __init mm_init(void)
asmlinkage void __init start_kernel(void)
{
char * command_line;
char * command_line, *after_dashes;
extern const struct kernel_param __start___param[], __stop___param[];
/*
......@@ -519,9 +540,13 @@ asmlinkage void __init start_kernel(void)
pr_notice("Kernel command line: %s\n", boot_command_line);
parse_early_param();
parse_args("Booting kernel", static_command_line, __start___param,
__stop___param - __start___param,
-1, -1, &unknown_bootoption);
after_dashes = parse_args("Booting kernel",
static_command_line, __start___param,
__stop___param - __start___param,
-1, -1, &unknown_bootoption);
if (after_dashes)
parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
set_init_arg);
jump_label_init();
......
......@@ -3193,6 +3193,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
{
struct module *mod;
long err;
char *after_dashes;
err = module_sig_check(info);
if (err)
......@@ -3277,10 +3278,15 @@ static int load_module(struct load_info *info, const char __user *uargs,
goto ddebug_cleanup;
/* Module is ready to execute: parsing args may do that. */
err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
-32768, 32767, unknown_module_param_cb);
if (err < 0)
after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
-32768, 32767, unknown_module_param_cb);
if (IS_ERR(after_dashes)) {
err = PTR_ERR(after_dashes);
goto bug_cleanup;
} else if (after_dashes) {
pr_warn("%s: parameters '%s' after `--' ignored\n",
mod->name, after_dashes);
}
/* Link in to syfs. */
err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
......
......@@ -177,13 +177,13 @@ static char *next_arg(char *args, char **param, char **val)
}
/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
int parse_args(const char *doing,
char *args,
const struct kernel_param *params,
unsigned num,
s16 min_level,
s16 max_level,
int (*unknown)(char *param, char *val, const char *doing))
char *parse_args(const char *doing,
char *args,
const struct kernel_param *params,
unsigned num,
s16 min_level,
s16 max_level,
int (*unknown)(char *param, char *val, const char *doing))
{
char *param, *val;
......@@ -198,6 +198,9 @@ int parse_args(const char *doing,
int irq_was_disabled;
args = next_arg(args, &param, &val);
/* Stop at -- */
if (!val && strcmp(param, "--") == 0)
return args;
irq_was_disabled = irqs_disabled();
ret = parse_one(param, val, doing, params, num,
min_level, max_level, unknown);
......@@ -208,22 +211,22 @@ int parse_args(const char *doing,
switch (ret) {
case -ENOENT:
pr_err("%s: Unknown parameter `%s'\n", doing, param);
return ret;
return ERR_PTR(ret);
case -ENOSPC:
pr_err("%s: `%s' too large for parameter `%s'\n",
doing, val ?: "", param);
return ret;
return ERR_PTR(ret);
case 0:
break;
default:
pr_err("%s: `%s' invalid for parameter `%s'\n",
doing, val ?: "", param);
return ret;
return ERR_PTR(ret);
}
}
/* All parsed OK. */
return 0;
return NULL;
}
/* Lazy bastard, eh? */
......
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