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Diffstat (limited to 'Documentation/i386/boot.txt')
| -rw-r--r-- | Documentation/i386/boot.txt | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/i386/boot.txt b/Documentation/i386/boot.txt index fc49b79bc1a..2eb16100bb3 100644 --- a/Documentation/i386/boot.txt +++ b/Documentation/i386/boot.txt @@ -170,6 +170,8 @@ Offset Proto Name Meaning 0238/4 2.06+ cmdline_size Maximum size of the kernel command line 023C/4 2.07+ hardware_subarch Hardware subarchitecture 0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data +0248/4 2.08+ payload_offset Offset of kernel payload +024C/4 2.08+ payload_length Length of kernel payload (1) For backwards compatibility, if the setup_sects field contains 0, the real value is 4. @@ -512,6 +514,32 @@ Protocol: 2.07+ A pointer to data that is specific to hardware subarch +Field name: payload_offset +Type: read +Offset/size: 0x248/4 +Protocol: 2.08+ + + If non-zero then this field contains the offset from the end of the + real-mode code to the payload. + + The payload may be compressed. The format of both the compressed and + uncompressed data should be determined using the standard magic + numbers. Currently only gzip compressed ELF is used. + +Field name: payload_length +Type: read +Offset/size: 0x24c/4 +Protocol: 2.08+ + + The length of the payload. + +**** THE IMAGE CHECKSUM + +From boot protocol version 2.08 onwards the CRC-32 is calculated over +the entire file using the characteristic polynomial 0x04C11DB7 and an +initial remainder of 0xffffffff. The checksum is appended to the +file; therefore the CRC of the file up to the limit specified in the +syssize field of the header is always 0. **** THE KERNEL COMMAND LINE |