From a2a9d67a26ec94a99ed29efbd61cf5be0a575678 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 6 Apr 2022 11:31:19 +0900 Subject: 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 Cc: Jonathan Corbet Cc: Randy Dunlap Cc: Nick Desaulniers Cc: Sami Tolvanen Cc: Nathan Chancellor Cc: Masahiro Yamada Cc: Linux Kbuild mailing list Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (Google) --- init/Kconfig | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) (limited to 'init/Kconfig') 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 -- cgit v1.2.3-59-g8ed1b