test11: fd0 with msdos showing garbage

test11: fd0 with msdos showing garbage

[Nicolai Lissner]

Greetings!
While doing a BIOS-Update for my board, I have tried to read/write an 
msdos-formatted disk with kernel 2.6.0-test11. It can be mounted without 
errors - but "ls" shows only garbage. The disk is 100% ok - and can be readed 
with kernel 2.4.x without problems. 

I have done some more investigation with that. I can format a disk with e2fs, 
even with msdos - both *seem* to work correct - data can be stored and readed 
- but if the disk have been formatted with msdos on another system it cannot 
be readed with test11. 
So I started to do a diskimage with "dd if=/dev/fd0 of=disk.image" 
- and found some interesting differences:
While kernel 2.4 produces a file of  1474560 bytes,
test11 produces a file of 737280 bytes only.

Comparing these files I found:

from offset 0x00000000 to 0x000013FF  -- no difference.
but... surprise ! 
The diskimage done with kernel 2.6.0-test11 shows the directory of the disk - 
beginning at offset 0x00001400

while it is expected at position 0x00002600 
(where it can be found when read with kernel 2.4)

The directory is followed by 0x00 bytes - next data is found at offset 
0x00002400 -- data, that can be found at offset 0x00004800 in the original 
image.

I can give more detailed information if needed.

Confused but not hopeless (hey, rest of test11 is works a charme here - :)

Nicolai

Re: test11: fd0 with msdos showing garbage

[Linus Torvalds]

On Sat, 13 Dec 2003, Nicolai Lissner wrote:
>
> While doing a BIOS-Update for my board, I have tried to read/write an
> msdos-formatted disk with kernel 2.6.0-test11. It can be mounted without
> errors - but "ls" shows only garbage. The disk is 100% ok - and can be readed
> with kernel 2.4.x without problems.
>
> I have done some more investigation with that. I can format a disk with e2fs,
> even with msdos - both *seem* to work correct - data can be stored and readed
> - but if the disk have been formatted with msdos on another system it cannot
> be readed with test11.
> So I started to do a diskimage with "dd if=/dev/fd0 of=disk.image"
> - and found some interesting differences:
> While kernel 2.4 produces a file of  1474560 bytes,
> test11 produces a file of 737280 bytes only.

Sounds like test11 mis-identified the floppy format.

> Comparing these files I found:
>
> from offset 0x00000000 to 0x000013FF  -- no difference.
> but... surprise !
> The diskimage done with kernel 2.6.0-test11 shows the directory of the disk -
> beginning at offset 0x00001400

Can you try using /dev/fd0H1440 instead of /dev/fd0?

Also, please set the FP_DEBUG flag in the floppy driver flags - something
like "floppy=debug" should do that for you. That should tell more about
the autoprobing..

		Linus

Problem with ASUS-A7V600 (was: test11: fd0 with msdos showing garbage)

[Nicolai Lissner]

[-- Attachment #1: Type: text/plain, Size: 880 bytes --]

Good news : )  it's not test11 that fails...

Sorry to say: This have been some sort of false alarm - 
although the problem still exists.

When I wrote "the disk is readed perfectly with kernel 2.4.x" I referred to 
tests on another machine that is running with kernel 2.4.23.

This other machine reads the disk perfectly even with test11 - 
so this is not a fd-problem of test11...
...it's a problem related to my hardware.

The "problem-machine" - with a mainboard ASUS A7V600 - does show the same 
disk-problems with kernel 2.4.x - probably because there is no support for 
the VIA KT600 chipset used on the board yet. I have experienced also problems 
with the serial port of the board that might or might not be related to the 
lack of support for the chipset.

I have attached the output of lspci (only the lines that are directly related 
to the mainboard itself)

Nicolai

[-- Attachment #2: lspci --]
[-- Type: text/plain, Size: 911 bytes --]

00:00.0 Host bridge: VIA Technologies, Inc. VT8377 [KT400 AGP] Host Bridge (rev 80)
00:01.0 PCI bridge: VIA Technologies, Inc.: Unknown device b198
00:0a.0 Ethernet controller: Digital Equipment Corporation DECchip 21040 [Tulip] (rev 23)
00:0f.0 RAID bus controller: VIA Technologies, Inc.: Unknown device 3149 (rev 80)
00:0f.1 IDE interface: VIA Technologies, Inc. VT82C586A/B/VT82C686/A/B/VT8233/A/C/VT8235 PIPC Bus Master IDE (rev 06)
00:10.0 USB Controller: VIA Technologies, Inc. USB (rev 81)
00:10.1 USB Controller: VIA Technologies, Inc. USB (rev 81)
00:10.2 USB Controller: VIA Technologies, Inc. USB (rev 81)
00:10.3 USB Controller: VIA Technologies, Inc. USB (rev 81)
00:10.4 USB Controller: VIA Technologies, Inc. USB 2.0 (rev 86)
00:11.0 ISA bridge: VIA Technologies, Inc.: Unknown device 3227
00:11.5 Multimedia audio controller: VIA Technologies, Inc. VT8233/A/8235 AC97 Audio Controller (rev 60)