diff --git a/MAINTAINERS b/MAINTAINERS
index b90535d923a0c46e6cea2e800eac0e19940068d9..abc8e6fee21eb8188d1c75f2e15fc3c10abe35a2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7457,6 +7457,7 @@ S: Maintained
F: Documentation/admin-guide/bootconfig.rst
F: fs/proc/bootconfig.c
F: include/linux/bootconfig.h
+F: lib/bootconfig-data.S
F: lib/bootconfig.c
F: tools/bootconfig/*
F: tools/bootconfig/scripts/*
diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h
index a4665c7ab07cb754f2b7fb71c443eadc3b11c1bd..1611f9db878e763699519a8b8efa3b714654e1e0 100644
--- a/include/linux/bootconfig.h
+++ b/include/linux/bootconfig.h
@@ -289,4 +289,14 @@ int __init xbc_get_info(int *node_size, size_t *data_size);
/* XBC cleanup data structures */
void __init xbc_exit(void);
+/* XBC embedded bootconfig data in kernel */
+#ifdef CONFIG_BOOT_CONFIG_EMBED
+const char * __init xbc_get_embedded_bootconfig(size_t *size);
+#else
+static inline const char *xbc_get_embedded_bootconfig(size_t *size)
+{
+ return NULL;
+}
+#endif
+
#endif
diff --git a/init/Kconfig b/init/Kconfig
index ddcbefe535e9e784d170bf2dd765dc0ad3e81652..2462d4ae2dc841f8e94256ab94fa9c38399fcdad 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 266d61bc67b03601eef7d3857d85999133476222..f7fe7cbb1df8eb063aacfc01e04d31b64fcd0d5b 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 @@ static void * __init get_boot_config_from_initrd(u32 *_size)
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 */
diff --git a/lib/.gitignore b/lib/.gitignore
index e5e217b8307b44ba593af0d6396359933ce4fa07..54596b634ecbfff06dff6f6e10a535b0982e6a3a 100644
--- a/lib/.gitignore
+++ b/lib/.gitignore
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
/crc32table.h
/crc64table.h
+/default.bconf
/gen_crc32table
/gen_crc64table
/oid_registry_data.c
diff --git a/lib/Makefile b/lib/Makefile
index 08053df16c7c878d0b3c8f011ff22c1960466cfd..95268d6c75b770fc84a298d30618603c2baaf562 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -280,6 +280,14 @@ $(foreach file, $(libfdt_files), \
lib-$(CONFIG_LIBFDT) += $(libfdt_files)
obj-$(CONFIG_BOOT_CONFIG) += bootconfig.o
+obj-$(CONFIG_BOOT_CONFIG_EMBED) += bootconfig-data.o
+
+$(obj)/bootconfig-data.o: $(obj)/default.bconf
+
+targets += default.bconf
+filechk_defbconf = cat $(or $(real-prereqs), /dev/null)
+$(obj)/default.bconf: $(CONFIG_BOOT_CONFIG_EMBED_FILE) FORCE
+ $(call filechk,defbconf)
obj-$(CONFIG_RBTREE_TEST) += rbtree_test.o
obj-$(CONFIG_INTERVAL_TREE_TEST) += interval_tree_test.o
diff --git a/lib/bootconfig-data.S b/lib/bootconfig-data.S
new file mode 100644
index 0000000000000000000000000000000000000000..ef85ba1a82f4a319d025f0ba1ccc82e8e5d28755
--- /dev/null
+++ b/lib/bootconfig-data.S
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Embed default bootconfig in the kernel.
+ */
+ .section .init.rodata, "aw"
+ .global embedded_bootconfig_data
+embedded_bootconfig_data:
+ .incbin "lib/default.bconf"
+ .global embedded_bootconfig_data_end
+embedded_bootconfig_data_end:
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 74f3201ab8e59e6201c02b5e97839cb148c9c880..c59d26068a6401990343e26c03002fcc4022ef98 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -12,6 +12,19 @@
#include <linux/kernel.h>
#include <linux/memblock.h>
#include <linux/string.h>
+
+#ifdef CONFIG_BOOT_CONFIG_EMBED
+/* embedded_bootconfig_data is defined in bootconfig-data.S */
+extern __visible const char embedded_bootconfig_data[];
+extern __visible const char embedded_bootconfig_data_end[];
+
+const char * __init xbc_get_embedded_bootconfig(size_t *size)
+{
+ *size = embedded_bootconfig_data_end - embedded_bootconfig_data;
+ return (*size) ? embedded_bootconfig_data : NULL;
+}
+#endif
+
#else /* !__KERNEL__ */
/*
* NOTE: This is only for tools/bootconfig, because tools/bootconfig will