Re: [PATCH]x86_64: build and use GDT on copied compressed kernel

[Yinghai Lu]

On 5/12/07, Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote:
> For data segments we never use that GDT, it is only for the code
> segment we use the GDT and that only to get us into 64bit mode.

after the patch
linux:/home/yhlu/xx/xx/kernel/linux-2.6/arch/x86_64/boot/compressed #
readelf -e vmlinux
...
Section Headers:
 [Nr] Name              Type             Address           Offset
      Size              EntSize          Flags  Link  Info  Align
 [ 0]                   NULL             0000000000000000  00000000
      0000000000000000  0000000000000000           0     0     0
 [ 1] .text             PROGBITS         0000000000000000  00100000
      000000000032617c  0000000000000000  AX       0     0     16
 [ 2] .rodata           PROGBITS         0000000000326180  00426180
      0000000000000400  0000000000000000   A       0     0     32
 [ 3] .eh_frame         PROGBITS         0000000000326580  00426580
      0000000000000210  0000000000000000   A       0     0     8
 [ 4] .data             PROGBITS         0000000000326790  00426790
      0000000000000008  0000000000000000  WA       0     0     8
 [ 5] .bss              NOBITS           00000000003267a0  00426798
      000000000000b860  0000000000000000  WA       0     0     32
 [ 6] .comment          PROGBITS         0000000000000000  00426798
      0000000000000035  0000000000000000           0     0     1
 [ 7] .shstrtab         STRTAB           0000000000000000  004267cd
      0000000000000047  0000000000000000           0     0     1
 [ 8] .symtab           SYMTAB           0000000000000000  00426a98
      00000000000007c8  0000000000000018           9    60     8
 [ 9] .strtab           STRTAB           0000000000000000  00427260
      0000000000000350  0000000000000000           0     0     1
Key to Flags:
 W (write), A (alloc), X (execute), M (merge), S (strings)
 I (info), L (link order), G (group), x (unknown)
 O (extra OS processing required) o (OS specific), p (processor specific)

after the patch, it seems .data section size still have 8 bytes.
before that will 0x28.
don't know what are the 8 bytes.

YH
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