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+What: /sys/kernel/boot_params
+Date: December 2013
+Contact: Dave Young <dyoung@redhat.com>
+Description: The /sys/kernel/boot_params directory contains two
+ files: "data" and "version" and one subdirectory "setup_data".
+ It is used to export the kernel boot parameters of an x86
+ platform to userspace for kexec and debugging purpose.
+
+ If there's no setup_data in boot_params the subdirectory will
+ not be created.
+
+ "data" file is the binary representation of struct boot_params.
+
+ "version" file is the string representation of boot
+ protocol version.
+
+ "setup_data" subdirectory contains the setup_data data
+ structure in boot_params. setup_data is maintained in kernel
+ as a link list. In "setup_data" subdirectory there's one
+ subdirectory for each link list node named with the number
+ of the list nodes. The list node subdirectory contains two
+ files "type" and "data". "type" file is the string
+ representation of setup_data type. "data" file is the binary
+ representation of setup_data payload.
+
+ The whole boot_params directory structure is like below:
+ /sys/kernel/boot_params
+ |__ data
+ |__ setup_data
+ | |__ 0
+ | | |__ data
+ | | |__ type
+ | |__ 1
+ | |__ data
+ | |__ type
+ |__ version
+
+Users: Kexec