The kernel source in RAM is covered by data

Hi,

I have port Linux on a PowerPc board. I have the following problems,
the kernel source is covered by data.
For example, after the kernel unzip by the loader, I have this mapping :

                  _start:
00000000: nop
00000004: nop
00000008: nop
                  __start:
0000000c: mr      r31,r3
00000010: mr      r30,r4
00000014: li      r24,0
00000018: bl      early_init
0000001c: bl      mmu_off
                  __after_mmu_off:
00000020: bl      clear_bats
00000024: bl      flush_tlbs
00000028: bl      initial_bats
0000002c: bl      setup_disp_bat
00000030: bl      reloc_offset

When the kernel launch the init process, I have an PageFault error. And the mapping is the following :

                  _start:
00000000: .long   0
00000004: .long   0xB0
00000008: .long   0x67DC28
                  __start:
0000000c: .long   0x3C5FD0
00000010: .long   0x1031C
00000014: .long   0x8001032
00000018: .long   0
0000001c:  .long   4
                  __after_mmu_off:
00000020: .long   1
00000024: .long   0x10590
00000028: .long   0x1032
0000002c: .long   0x1031C
00000030: .long   0x320000

Why the kernel space is modified? I have forgot a config in the kernel config? the advanced setup kernel config is the following :
CONFIG_ADVANCED_OPTIONS=y
CONFIG_HIGHMEM_START=0xfe000000
CONFIG_LOWMEM_SIZE_BOOL=y
CONFIG_LOWMEM_SIZE=0x30000000
CONFIG_KERNEL_START_BOOL=y
CONFIG_KERNEL_START=0x0
# CONFIG_TASK_SIZE_BOOL is not set
CONFIG_TASK_SIZE=0x80000000
CONFIG_BOOT_LOAD_BOOL=y
CONFIG_BOOT_LOAD=0x00400000

Thanks for your feedback,
Nicolas MEDERLE.

Cordialement,

Nicolas MEDERLE.