Task udevadm:X blocked at boot

[Darius Shade]

The 3.0.0-16 kernel is unable to boot due to udevadm hanging. I'm dual booting Windows 7 and Ubuntu 11.10 on my laptop, but when i try to boot ubuntu, it drops to BusyBox complaining about giving up waiting on the root device. ls /dev shows that the device file for my hard drive is not there. Adding "rootdelay=300" to the boot arguments allows my hard drive to be seen after approximately 4 minutes and the boot can continue fine. An inspection of /var/log/syslog shows that the udevadm task is being "blocked" at boot for a long time (see attachment). It seems to be related to ACPI as "acpi=off" allows me to boot normally, however any other acpi boot options, such as acpi=ht, acpi=noirq, and so forth do not fix the problem, and udevadm still hangs.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: linux-image-3.0.0-16-generic 3.0.0-16.28
ProcVersionSignature: Ubuntu 3.0.0-16.28-generic 3.0.17
Uname: Linux 3.0.0-16-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: NVidia [HDA NVidia], device 0: CONEXANT Analog [CONEXANT Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: darius 1483 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'NVidia'/'HDA NVidia at 0xf6480000 irq 34'
   Mixer name : 'Conexant CX20549 (Venice)'
   Components : 'HDA:14f15045,103c30cf,00100100'
   Controls : 20
   Simple ctrls : 9
Date: Mon Feb 13 22:48:11 2012
HibernationDevice: RESUME=UUID=9c6b2f19-75db-4204-b395-57f227ac57e5
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
Lsusb:
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 002 Device 002: ID 04f2:b023 Chicony Electronics Co., Ltd Gateway USB 2.0 Webcam
MachineType: Hewlett-Packard HP Pavilion dv9500 Notebook PC
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-16-generic root=UUID=b620339e-92d5-4656-85dc-afc620ce7049 ro acpi=off irqpoll quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.0.0-16-generic N/A
 linux-backports-modules-3.0.0-16-generic N/A
 linux-firmware 1.60
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/22/2011
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: F.34
dmi.board.name: 30D1
dmi.board.vendor: Quanta
dmi.board.version: 85.26
dmi.chassis.type: 10
dmi.chassis.vendor: Quanta
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnHewlett-Packard:bvrF.34:bd03/22/2011:svnHewlett-Packard:pnHPPaviliondv9500NotebookPC:pvrRev1:rvnQuanta:rn30D1:rvr85.26:cvnQuanta:ct10:cvrN/A:
dmi.product.name: HP Pavilion dv9500 Notebook PC
dmi.product.version: Rev 1
dmi.sys.vendor: Hewlett-Packard

[Joseph Salisbury (jsalisbury)]

Do you know if this issue happened in a previous version of Ubuntu, or is this a new issue?

Would it be possible for you to test the latest upstream kernel? It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.3 kernel[1] (Not a kernel in the daily directory). Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag(Only that one tag, please leave the other tags). This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text.

If this bug is fixed by the mainline kernel, please add the following tag 'kernel-fixed-upstream-KERNEL-VERSION'. For example, if kernel version 3.3-rc2 fixed the issue, the tag would be: 'kernel-fixed-upstream-v3.3-rc2'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[1] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.3-rc3-precise/

[Darius Shade (cookiedemkp)]

I tested the latest 3.3-rc3-precise kernel, but the same hanging issue still exists. However it seems to be no longer related to udev, but to swapper and kworker (see attached). 1 message is shown about swapper hanging, and another 5 or 6 are about kworker, all hanging the machine for the exact same as the last kernel, and the "acpi=off" boot argument still 'fixes' the problem and allows for a normal boot, but again not having acpi on a laptop isn't good. I have found other bugs reporting the same "task * blocked for more than 120 seconds", however none of them seem to be related to the boot process and therefore i am unable to find a bug that this might be a duplicate of.

[Darius Shade (cookiedemkp)]

Forgot to attach a screenshot, here it is, showing the new processes hanging

[Darius Shade (cookiedemkp)]

Update on the bug status, I tried using my hard drive with my other computer and ubuntu booted perfectly, so the problem definitely lies somewhere in the hardware/BIOS, though I have no idea how i would even begin diagnosing the problem. Possibly the ACPI of my BIOS is broken, though updating it does not seem to fix anything. Also, some possibly relevant information is that my Windows installation is unable to shut down. It will say shutting down, go to a black screen, and then sit there, not cutting the power off, leading me to believe that my BIOS's ACPI is definitely buggy/broken.

[penalvch (penalvch)]

Darius Shade, could you please confirm this issue exists with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ . If the issue remains, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux <replace-with-bug-number>

Also, could you please test the latest upstream kernel available following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Please do not test the daily folder, but the one all the way at the bottom. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-v3.11-rc5

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[Jan K. (jan-launchpad-kantert)]

I see the same problem in a fresh installed Ubuntu 14.04 LTS. However it only blocks for about 60s in my case. See the attached bootchart.

[penalvch (penalvch)]

Jan K., thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]