summaryrefslogtreecommitdiffstats
path: root/init
diff options
context:
space:
mode:
authorMasami Hiramatsu <mhiramat@kernel.org>2022-04-06 04:31:19 +0200
committerSteven Rostedt (Google) <rostedt@goodmis.org>2022-04-26 23:58:51 +0200
commita2a9d67a26ec94a99ed29efbd61cf5be0a575678 (patch)
treeb074eb9d609459cf78af18be15dfb7aaa1bd0d90 /init
parentbootconfig: Check the checksum before removing the bootconfig from initrd (diff)
downloadlinux-a2a9d67a26ec94a99ed29efbd61cf5be0a575678.tar.xz
linux-a2a9d67a26ec94a99ed29efbd61cf5be0a575678.zip
bootconfig: Support embedding a bootconfig file in kernel
This allows kernel developer to embed a default bootconfig file in the kernel instead of embedding it in the initrd. This will be good for who are using the kernel without initrd, or who needs a default bootconfigs. This needs to set two kconfigs: CONFIG_BOOT_CONFIG_EMBED=y and set the file path to CONFIG_BOOT_CONFIG_EMBED_FILE. Note that you still need 'bootconfig' command line option to load the embedded bootconfig. Also if you boot using an initrd with a different bootconfig, the kernel will use the bootconfig in the initrd, instead of the default bootconfig. Link: https://lkml.kernel.org/r/164921227943.1090670.14035119557571329218.stgit@devnote2 Cc: Padmanabha Srinivasaiah <treasure4paddy@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'init')
-rw-r--r--init/Kconfig21
-rw-r--r--init/main.c22
2 files changed, 32 insertions, 11 deletions
diff --git a/init/Kconfig b/init/Kconfig
index ddcbefe535e9..2462d4ae2dc8 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1351,7 +1351,7 @@ endif
config BOOT_CONFIG
bool "Boot config support"
- select BLK_DEV_INITRD
+ select BLK_DEV_INITRD if !BOOT_CONFIG_EMBED
help
Extra boot config allows system admin to pass a config file as
complemental extension of kernel cmdline when booting.
@@ -1361,6 +1361,25 @@ config BOOT_CONFIG
If unsure, say Y.
+config BOOT_CONFIG_EMBED
+ bool "Embed bootconfig file in the kernel"
+ depends on BOOT_CONFIG
+ help
+ Embed a bootconfig file given by BOOT_CONFIG_EMBED_FILE in the
+ kernel. Usually, the bootconfig file is loaded with the initrd
+ image. But if the system doesn't support initrd, this option will
+ help you by embedding a bootconfig file while building the kernel.
+
+ If unsure, say N.
+
+config BOOT_CONFIG_EMBED_FILE
+ string "Embedded bootconfig file path"
+ depends on BOOT_CONFIG_EMBED
+ help
+ Specify a bootconfig file which will be embedded to the kernel.
+ This bootconfig will be used if there is no initrd or no other
+ bootconfig in the initrd.
+
choice
prompt "Compiler optimization level"
default CC_OPTIMIZE_FOR_PERFORMANCE
diff --git a/init/main.c b/init/main.c
index 266d61bc67b0..f7fe7cbb1df8 100644
--- a/init/main.c
+++ b/init/main.c
@@ -266,7 +266,7 @@ static int __init loglevel(char *str)
early_param("loglevel", loglevel);
#ifdef CONFIG_BLK_DEV_INITRD
-static void * __init get_boot_config_from_initrd(u32 *_size)
+static void * __init get_boot_config_from_initrd(size_t *_size)
{
u32 size, csum;
char *data;
@@ -313,7 +313,7 @@ found:
return data;
}
#else
-static void * __init get_boot_config_from_initrd(u32 *_size)
+static void * __init get_boot_config_from_initrd(size_t *_size)
{
return NULL;
}
@@ -410,14 +410,16 @@ static int __init warn_bootconfig(char *str)
static void __init setup_boot_config(void)
{
static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
- const char *msg;
- int pos;
- u32 size;
- char *data, *err;
- int ret;
+ const char *msg, *data;
+ int pos, ret;
+ size_t size;
+ char *err;
/* Cut out the bootconfig data even if we have no bootconfig option */
data = get_boot_config_from_initrd(&size);
+ /* If there is no bootconfig in initrd, try embedded one. */
+ if (!data)
+ data = xbc_get_embedded_bootconfig(&size);
strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
@@ -436,8 +438,8 @@ static void __init setup_boot_config(void)
}
if (size >= XBC_DATA_MAX) {
- pr_err("bootconfig size %d greater than max size %d\n",
- size, XBC_DATA_MAX);
+ pr_err("bootconfig size %ld greater than max size %d\n",
+ (long)size, XBC_DATA_MAX);
return;
}
@@ -450,7 +452,7 @@ static void __init setup_boot_config(void)
msg, pos);
} else {
xbc_get_info(&ret, NULL);
- pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret);
+ pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret);
/* keys starting with "kernel." are passed via cmdline */
extra_command_line = xbc_make_cmdline("kernel");
/* Also, "init." keys are init arguments */