[Qemu-devel] QEMU won't load QCOW images under Windows

[Qemu-devel] QEMU won't load QCOW images under Windows

[André Braga]

The title says it all. If I try to start QEMU with a qcow image passed
as an argument to -hda , the emulator won't load. If I pass a raw
image instead, it works perfectly.

Wasn't QCOW supposed to address exactly a problem regarding Windows
and the lack of support for holes in the filesystem?

Any clues? Is there a strace equivalent for Windows so I can at least
try to track the problem down? (I'm not really fond of the mingw gdb
port, mind you...)




-- 
"A year spent in artificial intelligence is enough to make one believe in God"
Alan J. Perlis

[Qemu-devel] Re: QEMU won't load QCOW images under Windows

[Ronald]

Le Sat, 09 Oct 2004 00:42:37 -0300, André Braga a écrit :

> The title says it all. If I try to start QEMU with a qcow image passed as
> an argument to -hda , the emulator won't load. If I pass a raw image
> instead, it works perfectly.
> 
> Wasn't QCOW supposed to address exactly a problem regarding Windows and
> the lack of support for holes in the filesystem?
> 
> Any clues? Is there a strace equivalent for Windows so I can at least try
> to track the problem down? (I'm not really fond of the mingw gdb port,
> mind you...)

some observations:
I can't get infos from qcow images created under windows with qemu-img
under linux.
Qcow images created under linux and windows for the same base file,
don't differs only by the path of the base file.
I don't know if this is normal or not.
Here is two hexdump from qcow images created under linux and windows:

ronald@Athena$ hexdump -C slack.qco
00000000  51 46 49 fb 00 00 00 01  00 00 00 00 00 00 00 30  |QFIû...........0|
00000010  00 00 00 12 41 67 19 58  00 00 00 00 1f 40 00 00  |....Ag.X.....@..|
00000020  09 0c 00 00 00 00 00 00  00 00 00 00 00 00 00 48  |...............H|
00000030  2f 6d 6e 74 2f 64 6f 73  2f 73 6c 61 63 6b 2e 64  |/mnt/dos/slack.d|
00000040  73 6b 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |sk..............|
00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000810  00 00 00 00 00 00 00 00                           |........|
00000818

ronald@Athena$ hexdump -C slack.qcw
00000000  51 46 49 fb 00 00 00 01  00 00 00 00 00 00 00 2e  |QFIû............|
00000010  00 00 00 0c 19 58 41 67  00 00 00 00 1f 40 00 00  |.....XAg.....@..|
00000020  09 0c 00 00 00 00 00 00  00 00 00 00 00 40 43 3a  |.............@C:|
00000030  5c 73 6c 61 63 6b 2e 64  73 6b 00 00 00 00 00 00  |\slack.dsk......|
00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000810

[Qemu-devel] Re: QEMU won't load QCOW images under Windows

[Ronald]

Le Sat, 09 Oct 2004 14:27:11 +0200, Ronald a écrit :


> some observations:
> I can't get infos from qcow images created under windows with qemu-img
> under linux.

Same thing on the other side, I can't read linux qcow under win.

Re: [Qemu-devel] Re: QEMU won't load QCOW images under Windows

[André Braga]

On Sat, 09 Oct 2004 14:27:11 +0200, Ronald <look@reply.to> wrote:
> some observations:
> I can't get infos from qcow images created under windows with qemu-img
> under linux.
> Qcow images created under linux and windows for the same base file,
> don't differs only by the path of the base file.

BTW, have you tried running a baseless QCOW image created under Linux
on Windows? I'll eventually reinstall Debian Sid, but it'll take some
time before I'm actually able to.



--
"A year spent in artificial intelligence is enough to make one believe in God"
Alan J. Perlis

[Qemu-devel] Re: Re: QEMU won't load QCOW images under Windows

[Ronald]

Le Sat, 09 Oct 2004 15:51:39 -0300, André Braga a écrit :

> On Sat, 09 Oct 2004 14:27:11 +0200, Ronald <look@reply.to> wrote:
>> some observations:
>> I can't get infos from qcow images created under windows with qemu-img
>> under linux.
>> Qcow images created under linux and windows for the same base file,
>> don't differs only by the path of the base file.
> 
> BTW, have you tried running a baseless QCOW image created under Linux on
> Windows? I'll eventually reinstall Debian Sid, but it'll take some time
> before I'm actually able to.

I can already says that raw image converted to qcow with qemu-img under
linux actually works under windows, I've tried it 5 minutes ago.   

Re: [Qemu-devel] Re: Re: QEMU won't load QCOW images under Windows

[André Braga]

On Sat, 09 Oct 2004 21:25:42 +0200, Ronald <look@reply.to> wrote:
> I can already says that raw image converted to qcow with qemu-img under
> linux actually works under windows, I've tried it 5 minutes ago.

Great! Now I can do some serious meta-hacking of booting a ISO image
of any Linux live CD, attaching a raw disk image containing qemu-img
binary for Linux, creating a baseless QCOW there, and moving the image
back to Windows.

Wee :D

(Point to be taken: QEMU on Linux mostly works, but it needs some care
to be really useful on Windows. That's why I'm focusing on it.)



-- 
"A year spent in artificial intelligence is enough to make one believe in God"
Alan J. Perlis

[Qemu-devel] Re: QEMU won't load QCOW images under Windows

[Anand Kumria]

On Sat, 09 Oct 2004 14:27:11 +0200, Ronald wrote:

> Le Sat, 09 Oct 2004 00:42:37 -0300, André Braga a écrit :
> 
> ronald@Athena$ hexdump -C slack.qco
> 00000000  51 46 49 fb 00 00 00 01  00 00 00 00 00 00 00 30  |QFIû...........0|
> 00000010  00 00 00 12 41 67 19 58  00 00 00 00 1f 40 00 00  |....Ag.X.....@..|
                                                                   ^^^^
> 00000020  09 0c 00 00 00 00 00 00  00 00 00 00 00 00 00 48  |...............H|
> 00000030  2f 6d 6e 74 2f 64 6f 73  2f 73 6c 61 63 6b 2e 64  |/mnt/dos/slack.d|
> 00000040  73 6b 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |sk..............|
> 00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
> *
> 00000810  00 00 00 00 00 00 00 00                           |........|
> 00000818
> 
> ronald@Athena$ hexdump -C slack.qcw
> 00000000  51 46 49 fb 00 00 00 01  00 00 00 00 00 00 00 2e  |QFIû............|
> 00000010  00 00 00 0c 19 58 41 67  00 00 00 00 1f 40 00 00  |.....XAg.....@..|
                                                                   ^^^^
> 00000020  09 0c 00 00 00 00 00 00  00 00 00 00 00 40 43 3a  |.............@C:|
> 00000030  5c 73 6c 61 63 6b 2e 64  73 6b 00 00 00 00 00 00  |\slack.dsk......|
> 00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

Looks like an endian issue in qemu-img

Anand