Not so fast: zImage saving seems to differ from ramdisk.gz (Intel NAS SS4000-E)

[H <hans@lambermont.dyndns.org>]

H wrote on 20101215:
> RedBoot> fis list
> Name              FLASH addr  Mem addr    Length      Entry point
> zImage            0xF00C0000  0x01008000  0x00200000  0x01008000
> ramdisk.gz        0xF02C0000  0x01800000  0x00400000  0x01800000
> 
> RedBoot> x -b 0xF02C0000 -l 0x00400000
> F02C0000: 1F 8B 08 08 F3 D9 E7 45  02 03 72 61 6D 64 69 73 |.......E..ramdis|
> F02C0010: 6B 00 EC 7C 0D 60 54 D5  B5 F5 99 64 12 02 06 0C |k..|.`T....d....|
> ...

This looks fine for ramdisk.gz , however for zImage I get :

RedBoot> x -b 0xF00C0000 -l 0x00200000
F00C0000: 00 00 A0 E1 00 00 A0 E1  00 00 A0 E1 00 00 A0 E1 |................|
F00C0010: 00 00 A0 E1 00 00 A0 E1  00 00 A0 E1 00 00 A0 E1 |................|
F00C0020: 02 00 00 EA 18 28 6F 01  00 00 00 00 68 A4 14 00 |.....(o.....h...|
F00C0030: 01 70 A0 E1 00 80 A0 E3  00 20 0F E1 03 00 12 E3 |.p....... ......|
...

I don't think this is how a zImage should look like.

I assume it should be more similar to vmlinuz :
hexdump -C /vmlinuz | head
00000000  ea 05 00 c0 07 8c c8 8e  d8 8e c0 8e d0 31 e4 fb |.............1..|
00000010  fc be 2d 00 ac 20 c0 74  09 b4 0e bb 07 00 cd 10 |..-..  .t........|
00000020  eb f2 31 c0 cd 16 cd 19  ea f0 ff 00 f0 44 69 72 |..1..........Dir|
00000030  65 63 74 20 62 6f 6f 74  69 6e 67 20 66 72 6f 6d |ect booting from|
...

When I save the 'x -b 0xF00C0000 -l 0x00200000' output regardless and
process it like I did with ramdisk.gz I get :
file zImage 
zImage: data

What is going on here ?

-- Hans Lambermont