Using objdump to force a section to load with gdb.

Brendan Simon brendan@dgs.monash.edu.au
Tue Jun 15 17:11:00 GMT 1999


I have a linux kernel compiled for a mpc860 target and am trying to get
it to run by downloading it into memory using a background debugger
(BDM).  The boot code gets to the point where it trys to uncompress the
kernel but fails because the image isn't loaded into memory (only .text,
.rodata and .data are loaded).  I tried using objcopy to set the "image"
section to "load" but it does not seem to work.  How can I get gdb to
load the image section (either using a gdb command or binutils) ?

Thanks,
Brendan Simon.

Here is a before/after trace using objcopy --set-section-flags.  As you
can see, the load attribute is not set.  I've tried all combinations of
attributes but I can't get it to work.  Am I doing something wrong ?

powerpc-linux-objdump --section-headers myzimage
myzimage:     file format elf32-powerpc
Sections:
Idx Name          Size      VMA       LMA       File off  Algn
  0 .text         00004324  00100000  00100000  00010000  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  1 .rodata       00000460  00104330  00104330  00014330  2**4
                  CONTENTS, ALLOC, LOAD, READONLY, DATA
  2 .data         000002f8  00105000  00105000  00015000  2**2
                  CONTENTS, ALLOC, LOAD, DATA
  3 .bss          0000bbac  00106000  00106000  00016000  2**2
                  ALLOC
  4 image         0006ccbf  00000000  00000000  00016000  2**0
                  CONTENTS, READONLY

powerpc-linux-objcopy --set-section-flags=image=load myzimage

powerpc-linux-objdump --section-headers myzimage
myzimage:     file format elf32-powerpc
Sections:
Idx Name          Size      VMA       LMA       File off  Algn
  0 .text         00004324  00100000  00100000  00010000  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  1 .rodata       00000460  00104330  00104330  00014330  2**4
                  CONTENTS, ALLOC, LOAD, READONLY, DATA
  2 .data         000002f8  00105000  00105000  00015000  2**2
                  CONTENTS, ALLOC, LOAD, DATA
  3 .bss          0000bbac  00106000  00106000  00016000  2**2
                  ALLOC
  4 image         0006ccbf  00000000  00000000  00016000  2**0
                  CONTENTS




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