Bug 4983

Summary:	Paralell ZIP disappearing
Product:	IO/Storage	Reporter:	Peter (tuharsky)
Component:	SCSI	Assignee:	Mike Anderson (andmike)
Status:	REJECTED INSUFFICIENT_DATA
Severity:	normal	CC:	bunk, protasnb
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6.12.2	Subsystem:
Regression:	---	Bisected commit-id:
Attachments:	Here's my custom kernel config I use

Description Peter 2005-08-02 04:43:12 UTC

Distribution: Debian 3.1 Sarge

Hardware Environment: AMD Duron 1100, QDI Kinetiz 7E (KT-133), 256MB SDRAM,
Seagate 60GB HDD, TEAC D16G DVDRW, Pinnacle soundcard, Rtl8139 NIC, STB Velocity
128, USB scanner Microtek (unplugged from electricity)

Software Environment: 

Problem Description: I have Paralell port ZIP drive 100 connected to EPP LPT.
With recent kernel version, when I try to mount (as user), I get an error
"Special device /dev/sda4 does not exist".

And now the mystery begins:
I do (as root)# mount /dev/sda -t vfat /media/zip
I get strange error about not valid filesystem. Very strange because there is no
device at /dev/sda either! So I should get an "no such device" error, no just
complaint about filesystem! (The filesystem IS vfat on the ZIP however. But as I
said, the ZIP drive doesn't sit on /dev/sda anyway, and no other device does)

More strange, after that step, I am suddenly able to mount zip (as user) at
/dev/sda4 and normally use it!

I discovered, that if there is a medium inserted during boot process, problem
does not appear.

Steps to reproduce:

Comment 1 Peter 2005-08-02 04:47:25 UTC

Created attachment 5475 [details]
Here's my custom kernel config I use

Comment 2 Peter 2005-08-04 23:10:28 UTC

I hear change in sound of ZIP! If I don't let the medium in the drive during
boot, and then I insert the medium, the drive cliks twice! Anybody who works
with ZIP knows the click sound that appears when U insert the medium (probably
the startup of motors and movement of heads because of initial medium check or
so). So, the sound is doubled somehow when the bug is going to appear.

I don't know the structure of the driver, but for me being not kernel hacker it
looks like some bad value sits somewhere in kernel variables (SCSI, ATAPI or
whatever) when computer boots without medium inserted in ZIP drive.

Comment 3 Peter 2005-09-12 23:38:00 UTC

When I run LILO after ZIP problems, I get "Fatal: open /dev/sda does no exist"
or whatever. Then I try to run LILO again, and it is OK.

The error happens whenever in the same session (=until reboot)

Comment 4 Peter 2005-09-12 23:40:07 UTC

With 2.6.13.1 the bug seems to dissapear. Is it accidentally or knowlingly? :o)
Should it be marked as "Resolved", or better let it be "NEW" some time?

Comment 5 Andrew Morton 2006-01-16 02:30:42 UTC

If the bug is still absent from 2.6.15 then yes, please mark this as resolved.

Comment 6 Peter 2006-01-18 03:18:09 UTC

Hmm, in 2.6.15, bug is there.

Comment 7 Peter 2006-09-14 00:32:27 UTC

I bought a new MP3 player Emgeton E5Cult. It serves as USB Mass Storage device
too, 1GB, nice machine.

Hence I discovered a new kind of behaviour of this bug (kernel 2.6.17.13):

I plugged the Player to USB, mounted as /dev/sdb1.
Now the ZIP cannot be mounted at usual /dev/sda4, "does not exist" message.

$ lsscsi -gv
[0:0:6:0]    disk    IOMEGA   ZIP 100          D.09  -         /dev/sg0
  dir: /sys/devices/platform/host0/target0:0:6/0:0:6:0
[1:0:0:0]    disk    SigmaTel MSCN             0100  -         /dev/sg1
  dir:
/sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host1/target1:0:0/1:0:0:0


I unmount Player and unplug from USB.
ZIP still cannot be mounted at /dev/sda4.

$ lsscsi -gv
[0:0:6:0]    disk    IOMEGA   ZIP 100          D.09  -         /dev/sg0
  dir: /sys/devices/platform/host0/target0:0:6/0:0:6:0


And now the obligatory part of the bug's behaviour:
I rename the ZIP in /etc/fstab to from /dev/sda4 to /dev/sda and attemp to
mount. I get the strange error "wrong fs type".
Renamed back to /dev/sda4 and now mounted flawlessly!


I could understand if the ZIP just "migrated" because of kinda position
re-ordering after the USB device was plugged in.
However, the Player plugged to USB is usually assigned to /dev/sdb1 here (with
or without the ZIP mounted), and ZIP is _always_ at /dev/sda4.

And it seems, that ZIP (sda4) really disappears from /dev directory when player
is plugged to USB for the first time.
Couldn't also understand, why it is still blocked after unplugging the USB, and
why does it recover itself after unsuccessful attemp to mount /dev/sda.

Comment 8 Natalie Protasevich 2007-07-05 00:41:54 UTC

Peter,
Please confirm if the problem still exists with new kernels (2.6.22+, recent one was rc7). Have you moved up to newer distro? This can be a user level hot plug issue (udev, hald agents that provide "plug and play" device capabilities).
Thanks.

Comment 9 Adrian Bunk 2007-09-06 07:53:15 UTC

Please reopen this bug if it's still present with kernel 2.6.22.