Bug 248466 - race between loading xenblk.ko and scanning for LVM partitions etc.
race between loading xenblk.ko and scanning for LVM partitions etc.
Status: CLOSED WONTFIX
Product: Fedora
Classification: Fedora
Component: kernel-xen (Show other bugs)
6
All Linux
low Severity low
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Assigned To: Eduardo Habkost
Virtualization Bugs
bzcl34nup
: Patch
Depends On: 248462
Blocks:
  Show dependency treegraph
 
Reported: 2007-07-16 17:18 EDT by Eduardo Habkost
Modified: 2009-12-14 15:41 EST (History)
2 users (show)

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Fixed In Version:
Doc Type: Bug Fix
Doc Text:
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Clone Of:
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Last Closed: 2008-05-06 15:42:40 EDT
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oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
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Comment 1 Eduardo Habkost 2007-07-16 17:21:23 EDT
Clone of bug #247265, for Fedora 6.

+++ This bug was initially created as a clone of Bug #247265 +++

Description of problem:
When the xen block frontend driver is built as a module the module load is 
only
synchronous up to the point where the frontend and the backend become 
connected
rather than when the disk is added.

This means that there can be a race on boot between loading the module and
loading the dm-* modules and doing the scan for LVM physical volumes (all in 
the
initrd). In the failure case the disk is not present until after the scan for
physical volumes is complete.

Version-Release number of selected component (if applicable): 2.6.18-8.1.6.EL
Also applies to RHEL4u5 2.6.9-55.0.2.EL

Upstream fix is:
http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/11483a00c017
http://xenbits.xensource.com/kernels/rhel4x.hg?rev/156e3eaca552

How reproducible:
Not precisely determined. Seems to be related to high load in domain 0 or in
multiple other domains implying delays in scheduling the backend driver. 

Actual results:
  Loading xenblk.ko module
  Registering block device major 202
  xvda:Loading dm-mod.ko module
  <6>device-mapper: ioctl: 4.11.0-ioctl (2006-09-14) initialised:
dm-devel@redhat.com
  Loading dm-mirror.ko module
  Loading dm-zero.ko module
  Loading dm-snapshot.ko module
  Making device-mapper control node
  Scanning logical volumes
  Reading all physical volumes. This may take a while...
  xvda1 xvda2
  No volume groups found
  Activating logical volumes
  Volume group "VolGroup00" not found
  Creating root device.
  Mounting root filesystem.
  mount: could not find filesystem '/dev/root'
  Setting up other filesystems.
  Setting up new root fs
  setuproot: moving /dev failed: No such file or directory
  no fstab.sys, mounting internal defaults
  setuproot: error mounting /proc: No such file or directory
  setuproot: error mounting /sys: No such file or directory
  Switching to new root and running init.
  unmounting old /dev
  unmounting old /proc
  unmounting old /sys
  switchroot: mount failed: No such file or directory
  Kernel panic - not syncing: Attempted to kill init!

Expected results:
  Registering block device major 202
  xvda: xvda1 xvda2
  Loading dm-mod.ko module
  device-mapper: ioctl: 4.11.0-ioctl (2006-09-14) initialised: 
dm-devel@redhat.com
  Loading dm-mirror.ko module
  Loading dm-zero.ko module
  Loading dm-snapshot.ko module
  Making device-mapper control node
  Scanning logical volumes
  Reading all physical volumes. This may take a while...
  Found volume group "VolGroup00" using metadata type lvm2
  Activating logical volumes
  2 logical volume(s) in volume group "VolGroup00" now active

--------------------------

(I should learn to review the bug description before cloning)
Comment 2 Red Hat Bugzilla 2007-07-24 21:42:59 EDT
change QA contact
Comment 3 Eduardo Habkost 2007-07-31 10:09:52 EDT
Fix on CVS, revision 1.2999.

kernel-xen-2.6-2.6.20-1.2999.fc6 submitted for pushing to updates-testing.
Comment 4 Bug Zapper 2008-04-04 03:28:06 EDT
Fedora apologizes that these issues have not been resolved yet. We're
sorry it's taken so long for your bug to be properly triaged and acted
on. We appreciate the time you took to report this issue and want to
make sure no important bugs slip through the cracks.

If you're currently running a version of Fedora Core between 1 and 6,
please note that Fedora no longer maintains these releases. We strongly
encourage you to upgrade to a current Fedora release. In order to
refocus our efforts as a project we are flagging all of the open bugs
for releases which are no longer maintained and closing them.
http://fedoraproject.org/wiki/LifeCycle/EOL

If this bug is still open against Fedora Core 1 through 6, thirty days
from now, it will be closed 'WONTFIX'. If you can reporduce this bug in
the latest Fedora version, please change to the respective version. If
you are unable to do this, please add a comment to this bug requesting
the change.

Thanks for your help, and we apologize again that we haven't handled
these issues to this point.

The process we are following is outlined here:
http://fedoraproject.org/wiki/BugZappers/F9CleanUp

We will be following the process here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping to ensure this
doesn't happen again.

And if you'd like to join the bug triage team to help make things
better, check out http://fedoraproject.org/wiki/BugZappers
Comment 5 Bug Zapper 2008-05-06 15:42:38 EDT
This bug is open for a Fedora version that is no longer maintained and
will not be fixed by Fedora. Therefore we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen thus bug against that version.

Thank you for reporting this bug and we are sorry it could not be fixed.

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