Add a description about the endianness of the size and the checksum fields. Those must be stored as le32 instead of u32. This will allow us to apply bootconfig to the cross build initrd without caring the endianness. Reported-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> --- Documentation/admin-guide/bootconfig.rst | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst index 363599683784..9b90efcc3a35 100644 --- a/Documentation/admin-guide/bootconfig.rst +++ b/Documentation/admin-guide/bootconfig.rst @@ -140,7 +140,9 @@ Since the boot configuration file is loaded with initrd, it will be added to the end of the initrd (initramfs) image file with padding, size, checksum and 12-byte magic word as below. -[initrd][bootconfig][padding][size(u32)][checksum(u32)][#BOOTCONFIG\n] +[initrd][bootconfig][padding][size(le32)][checksum(le32)][#BOOTCONFIG\n] + +The size and checksum fields are unsigned 32bit little endian value. When the boot configuration is added to the initrd image, the total file size is aligned to 4 bytes. To fill the gap, null characters
