hang on open("/dev/scd0")

Closing task on ubiquity because evand suggested to me in chat that it should be considered a kernel bug.

Thank you for taking the time to report this bug and helping to make Ubuntu better. Unfortunately we can't fix it, because your description does not yet have enough information.

Please include the following additional information, if you have not already done so (pay attention to lspci's additional options), as required by the Ubuntu Kernel Team:
1. Please include the output of the command "uname -a" in your next response. It should be one, long line of text which includes the exact kernel version you're running, as well as the CPU architecture.
2. Please run the command "dmesg > dmesg.log" after a fresh boot and attach the resulting file "dmesg.log" to this bug report.
3. Please run the command "sudo lspci -vvnn > lspci-vvnn.log" and attach the resulting file "lspci-vvnn.log" to this bug report.

For your reference, the full description of procedures for kernel-related bug reports is available at [WWW] http://wiki.ubuntu.com/KernelTeamBugPolicies. Thanks in advance!

I finally got back to this. I'm booted off of the Kubutu Gutsy CD, off of a different computer (but same model).
The same problem exists.

ubuntu@ubuntu:~$ uname -a
Linux ubuntu 2.6.22-14-generic #1 SMP Sun Oct 14 23:05:12 GMT 2007 i686 GNU/Linux
ubuntu@ubuntu:~$

Attached is dmesg.log

Since launchpad only allows one attachment, i'll have to attach lspci-vvnn.log in a separate comment.

-Ted Merrill

Now i'm attaching the output of sudo lspci -vvnn > lspci-vvnn.log

Oh yes, /proc/version_signature yields:
Ubuntu 2.6.22-14.46-generic

As i mentioned, on different hardware (but same model), i get the same problem for which the same workaround works...

-Ted Merrill

Assigning ubuntu-kernel-team rather than me, and marking as Confirmed (was Incomplete)

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue that you reported is one that should be reproducible with the live environment of the Desktop CD of the development release - Hardy Heron. It would help us greatly if you could test with it so we can work on getting it fixed in the next release of Ubuntu. You can find out more about the development release at [WWW] http://www.ubuntu.com/testing/ . Thanks again and we appreciate your help.

This patch can be applied as a quick hack, while the kernel guys are working on it.

This patch can be applied as a quick hack, while the kernel guys are working on it.

Beginning with the Hardy Heron 8.04 development cycle, all open Ubuntu kernel bugs need to be reported against the "linux" kernel package. We are automatically migrating this bug to the new "linux" package. However, development has already began for the upcoming Intrepid Ibex 8.10 release. It would be helpful if you could test the upcoming release and verify if this is still an issue - http://www.ubuntu.com/testing . If the issue still exists, please update this report by changing the Status of the "linux" task from "Incomplete" to "New". We appreciate your patience and understanding as we make this transition. Thanks!

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

Tried with 2.6.27-2-generic, the problem persists. When trying to mount a cd, the system hangs.

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

@yaman --- when you say hang, so you mean that the machine stops completly dead when the issue occurs. is it possible to login to the machine remotly? is it possible to switch to an alternate VT with ctrl-alt-f1 etc? It is possible the kernel is panic'ing and peoducing messages on VT1. Another sensible test would be to trigger the fault by opening the device using 'dd' after a delay, and switching to VT1 before the problem occurs, a panic may be visible there. I would recommend trying this with a final version of either Intrepid or Jaunty you appear to have used an early Intrepid previously. Please report back here.

@andy: Yes, the machine completely used to freeze in my previous tries(No,
VT switching, lock keys gone dead). dd perfectly read data from the dvd
inserted when the cd is not mounted. Another thing is that the system does
not try to automount in Jaunty(contrary to previous releases). When I
execute mount the system freezes. I don't recall kernel panics or
notifications from my pre-Jaunty tries, right now due to lack of VT's i can
not check. The cause is the pata_marvell driver i think.

Now to make things more interesting, in my second try after rebooting, i got
this instead of a crash;

root@endor:/etc# mount /dev/scd0 /media/cdrom0/
mount: /dev/sr0: unknown device

And, the dd part:
root@endor:/etc# dd if=/dev/scd0 of=out
dd: opening `/dev/scd0': No medium found

I might have time in weekend to inspect the problem in the weekend, so if
anything i can help with let me know.

On Tue, Apr 28, 2009 at 1:28 PM, Andy Whitcroft <email address hidden> wrote:

> @yaman --- when you say hang, so you mean that the machine stops
> completly dead when the issue occurs. is it possible to login to the
> machine remotly? is it possible to switch to an alternate VT with ctrl-
> alt-f1 etc? It is possible the kernel is panic'ing and peoducing
> messages on VT1. Another sensible test would be to trigger the fault by
> opening the device using 'dd' after a delay, and switching to VT1 before
> the problem occurs, a panic may be visible there. I would recommend
> trying this with a final version of either Intrepid or Jaunty you appear
> to have used an early Intrepid previously. Please report back here.
>
> ** Changed in: linux (Ubuntu)
> Status: Incomplete => In Progress
>
> ** Changed in: linux (Ubuntu)
> Status: In Progress => Incomplete
>
> ** Changed in: linux (Ubuntu)
> Assignee: (unassigned) => Andy Whitcroft (apw)
>
> --
> hang on open("/dev/scd0", ... was gutsy ubiquity and partprobe hang
> https://bugs.launchpad.net/bugs/156052
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in “linux” source package in Ubuntu: Incomplete
> Status in “linux-source-2.6.22” source package in Ubuntu: Won't Fix
> Status in “ubiquity” source package in Ubuntu: Invalid
>
> Bug description:
> Boot either live cd:
> ubuntu-7.10-desktop-i386
> kubuntu-7.10-desktop-i386
>
> I have more detailed information about the kubuntu disk,
> but the same problem appeared with the ubuntu disk
>
> Using kubuntu live cd:
> Click on installer
> answer three questions
> it then says "scanning disk" and at some percentage (46%?)
> it freezes... only recourse is to power cycle.
> This is repeatable.
>
> Ok, try some other things.
> Finally i try something that narrows it down:
>
> strace partprobe -d -s
> This hangs at:
> open("/dev/scd0", ...
>
> Ok, boot the live cd again, this time do:
> rm /dev/scd0
> (as root of course)
> Now click on the install icon.
>
> Everything works!
> But three hours lost out of my life :~)
>
> Here is the relevent lshw output:
>
> *-pci:1
> description: PCI bridge
> product: 82801H (ICH8 Family) PCI Express Port 2
> vendor: Intel Corporation
> ...

@yaman -- that definately sounds like a hard crash if caps-lock no longer works. Normally the kernel produces a stack trace in association with that. It would normally appear on the real console (VT-1) when it occurs. We may get to see that stack trace if you switch to VT-1 (via ctrl-alt-f1) and then login there. Once logged in run the following command to get the maximum visible lines:

    setfont /usr/share/consolefonts/Uni1-VGA8.psf.gz

Then while still on VT-1 insert the CD. If we are lucky we should see messages on the screen at that point. We would want to get that information into this bug, a digital photograph of this output is a good way to do this.

yaman and ted, is this something you still experience (even in lucid if you can try)?

Closing due to lack of response. If this issue is still present for the Original Reporter, please reopen and provide the information from the latest release.

Thanks!

~JFo