mirror of
https://github.com/ipxe/ipxe
synced 2025-12-16 01:21:10 +03:00
d5d68b2e31
The option ROM header contains a one-byte field indicating the number of 512-byte sectors in the ROM image. Currently it is linked to contain the number of uncompressed sectors, with an instruction to the compressor to correct it. This causes link failure when the uncompressed size of the ROM image is over 128k. Fix by replacing the SUBx compressor fixup with an ADDx fixup that adds the total compressed output length, scaled as requested, to an addend stored in the field where the final length value will be placed. This is similar to the behavior of ELF relocations, and ensures that an overflow error will not be generated unless the compressed size is still too large for the field. This also allows us to do away with the _filesz_pgh and _filesz_sect calculations exported by the linker script. Output tested bitwise identical to the old SUBx mechanism on hd, dsk, lkrn, and rom prefixes, on both 32-bit and 64-bit processors. Modified-by: Michael Brown <mcb30@etherboot.org> Signed-off-by: Michael Brown <mcb30@etherboot.org>
78 lines
1.6 KiB
ArmAsm
78 lines
1.6 KiB
ArmAsm
.text
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.arch i386
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.code16
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.section ".prefix", "ax", @progbits
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.org 0
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nbi_header:
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/*****************************************************************************
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* NBI file header
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*****************************************************************************
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*/
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file_header:
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.long 0x1b031336 /* Signature */
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.byte 0x04 /* 16 bytes header, no vendor info */
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.byte 0
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.byte 0
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.byte 0 /* No flags */
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.word 0x0000, 0x07c0 /* Load header to 0x07c0:0x0000 */
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.word entry, 0x07c0 /* Start execution at 0x07c0:entry */
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.size file_header, . - file_header
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/*****************************************************************************
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* NBI segment header
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*****************************************************************************
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*/
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segment_header:
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.byte 0x04 /* 16 bytes header, no vendor info */
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.byte 0
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.byte 0
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.byte 0x04 /* Last segment */
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.long 0x00007e00
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imglen: .long -512
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memlen: .long -512
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.size segment_header, . - segment_header
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.section ".zinfo.fixup", "a", @progbits /* Compressor fixups */
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.ascii "ADDL"
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.long imglen
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.long 1
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.long 0
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.ascii "ADDL"
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.long memlen
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.long 1
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.long 0
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.previous
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/*****************************************************************************
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* NBI entry point
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*****************************************************************************
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*/
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entry:
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/* Install gPXE */
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call install
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/* Jump to .text16 segment */
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pushw %ax
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pushw $1f
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lret
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.section ".text16", "awx", @progbits
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1:
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pushl $main
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pushw %cs
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call prot_call
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popl %ecx /* discard */
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/* Uninstall gPXE */
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call uninstall
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/* Reboot system */
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int $0x19
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.previous
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.size entry, . - entry
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nbi_header_end:
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.org 512
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