[Bug 1900779] [NEW] xp /16i on arm mixes DWords

[Chaoscode]

Public bug reported:

I was working with qemuand wanted to understag ATAG structure.
In Monitor mode I used xp /16i 0x100 and I got really confused.
with xp /16i 0x100:
At address 0x120 the DWords are 0x00000000, 0x00000004, 0x54410009, 0x74736574
with xp /16x 0x100:
At address 0x120 the DWords are 0x54410001, 0x00000001, 0x00000001, 0x00000000

from my Terminal:

(qemu) xp /16x 0x100
0000000000000100: 0x00000005 0x54410001 0x00000001 0x00001000
0000000000000110: 0x00000000 0x00000004 0x54410002 0x3c000000
0000000000000120: 0x00000000 0x00000004 0x54410009 0x74736574
0000000000000130: 0x00000000 0x00000000 0x00000000 0x00000000
(qemu) xp /16i 0x100
0x00000100:  00000005  andeq    r0, r0, r5
0x00000104:  54410001  strbpl   r0, [r1], #-1
0x00000108:  00000001  andeq    r0, r0, r1
0x0000010c:  00001000  andeq    r1, r0, r0
0x00000110:  00000000  andeq    r0, r0, r0
0x00000114:  00000004  andeq    r0, r0, r4
0x00000118:  54410002  strbpl   r0, [r1], #-2
0x0000011c:  3c000000  .byte    0x00, 0x00, 0x00, 0x3c
0x00000120:  54410001  strbpl   r0, [r1], #-1
0x00000124:  00000001  andeq    r0, r0, r1
0x00000128:  00001000  andeq    r1, r0, r0
0x0000012c:  00000000  andeq    r0, r0, r0
0x00000130:  00000004  andeq    r0, r0, r4
0x00000134:  54410002  strbpl   r0, [r1], #-2
0x00000138:  3c000000  .byte    0x00, 0x00, 0x00, 0x3c
0x0000013c:  00000000  andeq    r0, r0, r0
(increasing length only results in more 00000000  andeq    r0, r0, r0 Lines)

Version:
4.2.1Debian 1:4.2-3ubuntu6.6
Commandline:
qemu-system-arm -machine raspi2 --nographic -S -s -kernel ./vmlinuz --append 
"test"
./vmlinuz is a x64 linux kernel. I didn't care about architecture because i 
just wanted to see ATAG structure.
I also tried
qemu-system-arm -machine raspi2 --nographic -S -s -kernel ./overview.pdf 
--append "test"
same result.

** Affects: qemu
     Importance: Undecided
         Status: New


** Tags: bytes disassembly mixes

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https://bugs.launchpad.net/bugs/1900779

Title:
  xp /16i on arm mixes DWords

Status in QEMU:
  New

Bug description:
  I was working with qemuand wanted to understag ATAG structure.
  In Monitor mode I used xp /16i 0x100 and I got really confused.
  with xp /16i 0x100:
  At address 0x120 the DWords are 0x00000000, 0x00000004, 0x54410009, 0x74736574
  with xp /16x 0x100:
  At address 0x120 the DWords are 0x54410001, 0x00000001, 0x00000001, 0x00000000

  from my Terminal:

  (qemu) xp /16x 0x100
  0000000000000100: 0x00000005 0x54410001 0x00000001 0x00001000
  0000000000000110: 0x00000000 0x00000004 0x54410002 0x3c000000
  0000000000000120: 0x00000000 0x00000004 0x54410009 0x74736574
  0000000000000130: 0x00000000 0x00000000 0x00000000 0x00000000
  (qemu) xp /16i 0x100
  0x00000100:  00000005  andeq    r0, r0, r5
  0x00000104:  54410001  strbpl   r0, [r1], #-1
  0x00000108:  00000001  andeq    r0, r0, r1
  0x0000010c:  00001000  andeq    r1, r0, r0
  0x00000110:  00000000  andeq    r0, r0, r0
  0x00000114:  00000004  andeq    r0, r0, r4
  0x00000118:  54410002  strbpl   r0, [r1], #-2
  0x0000011c:  3c000000  .byte    0x00, 0x00, 0x00, 0x3c
  0x00000120:  54410001  strbpl   r0, [r1], #-1
  0x00000124:  00000001  andeq    r0, r0, r1
  0x00000128:  00001000  andeq    r1, r0, r0
  0x0000012c:  00000000  andeq    r0, r0, r0
  0x00000130:  00000004  andeq    r0, r0, r4
  0x00000134:  54410002  strbpl   r0, [r1], #-2
  0x00000138:  3c000000  .byte    0x00, 0x00, 0x00, 0x3c
  0x0000013c:  00000000  andeq    r0, r0, r0
  (increasing length only results in more 00000000  andeq    r0, r0, r0 Lines)

  Version:
  4.2.1Debian 1:4.2-3ubuntu6.6
  Commandline:
  qemu-system-arm -machine raspi2 --nographic -S -s -kernel ./vmlinuz --append 
"test"
  ./vmlinuz is a x64 linux kernel. I didn't care about architecture because i 
just wanted to see ATAG structure.
  I also tried
  qemu-system-arm -machine raspi2 --nographic -S -s -kernel ./overview.pdf 
--append "test"
  same result.

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