1What: /sys/kernel/boot_params 2Date: December 2013 3Contact: Dave Young <dyoung@redhat.com> 4Description: The /sys/kernel/boot_params directory contains two 5 files: "data" and "version" and one subdirectory "setup_data". 6 It is used to export the kernel boot parameters of an x86 7 platform to userspace for kexec and debugging purpose. 8 9 If there's no setup_data in boot_params the subdirectory will 10 not be created. 11 12 "data" file is the binary representation of struct boot_params. 13 14 "version" file is the string representation of boot 15 protocol version. 16 17 "setup_data" subdirectory contains the setup_data data 18 structure in boot_params. setup_data is maintained in kernel 19 as a link list. In "setup_data" subdirectory there's one 20 subdirectory for each link list node named with the number 21 of the list nodes. The list node subdirectory contains two 22 files "type" and "data". "type" file is the string 23 representation of setup_data type. "data" file is the binary 24 representation of setup_data payload. 25 26 The whole boot_params directory structure is like below: 27 /sys/kernel/boot_params 28 |__ data 29 |__ setup_data 30 | |__ 0 31 | | |__ data 32 | | |__ type 33 | |__ 1 34 | |__ data 35 | |__ type 36 |__ version 37 38Users: Kexec 39