Pkg xen devel - Oct 2008 - Bug#503046: xen-utils-3.2-1: inadequate error handling for the case of a failure to use a loopback device

Package: xen-utils-3.2-1
Version: 3.2.1-2
Severity: normal

When a DomU is defined as using a file: device the loopback driver will
be used to make it appear to be a regular block device.  The loopback
driver will by default only support 8 nodes so this is a limited
resource.

http://etbe.coker.com.au/2008/10/22/kernel-issues-with-debian-xen-and-centos-kernels/

If there is a problem that prevents correctly allocating the block
device (see the above URL for a description of how I encountered it when
using a CentOS kernel) then it will not free the loop device.  When the
domain is destroyed with "xm destroy" it will leave the loopback
device,
if you run that a few times (EG you have a script to restart DomU's on
error) then you run out of loopback devices for the system.

The error handling code needs to deal with this case.

Control: tags -1 +moreinfo

On Wed, 22 Oct 2008 14:20:10 +1100 Russell Coker <russell at coker.com.au>
wrote:

Thanks for the report, sorry that it seems to have slipped through the
cracks.
> If there is a problem that prevents correctly allocating the block
> device (see the above URL for a description of how I encountered it when
> using a CentOS kernel) then it will not free the loop device.  When the
> domain is destroyed with "xm destroy" it will leave the loopback
device,
> if you run that a few times (EG you have a script to restart DomU's on
> error) then you run out of loopback devices for the system.
> 
> The error handling code needs to deal with this case.
Looking at the current upstream code it seems things have changed since
this report was filed, and I know that xl is a bit better about
handling of when the hotplug scripts are run on teardown etc.

So I have a reasonably high hope that this issue has gone away, can you
confirm?

Thanks,

Ian.

Processing control commands:
> tags -1 +moreinfo
Bug #503046 [src:xen] xen-utils-3.2-1: inadequate error handling for the case of
a failure to use a loopback device
Added tag(s) moreinfo.

-- 
503046: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=503046
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems

Processing control commands:
> tags -1 +moreinfo
Bug #503046 [src:xen] xen-utils-3.2-1: inadequate error handling for the case of
a failure to use a loopback device
Ignoring request to alter tags of bug #503046 to the same tags previously set

-- 
503046: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=503046
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems

Hi Russell,

This is about Debian bug report #503046 that you filed
before in the Debian bug tracker, against the Xen packages.

Your bug report was targeted at a Xen package in a Debian distribution
older than the current stable (Stretch).

Can you please help us by confirming that any of the following scenarios
does apply to your situation?

* I had this problem a long time ago. It was never solved, but I found a
workaround, which is ...
* I had this problem a long time ago, and I solved it by not using Xen
any more, but by doing ...
* I still experience this problem, and I'm still using Xen
3.2/4.1/4.4/etc. I cannot upgrade to Debian Stretch or Buster because ...
* I had this problem, and since upgrading to Stretch / Buster / ? it
seems it was solved, and I forgot to report it again. Please close it,
thanks.
* Other: ...

Note that even if you found a solution, it's still very useful to report
it back to our bug tracker. There might be someone else running into the
same problem, who can be helped with your information.

Please note that unless there's a response within a while from now, we
will close the bug report. If you discover this message later, and this
case is important to you, then you can try unarchiving the bug and
replying to it, or reach out to the maintainers email list at
pkg-xen-devel at lists.alioth.debian.org (no subscription required) and
post a message.

Thanks,
Hans van Kranenburg

Your message dated Fri, 22 Feb 2019 22:28:03 +0100
with message-id <79dbac90-249d-cb00-8be6-60bcef1433b0 at knorrie.org>
and subject line Re: xen-utils-3.2-1: inadequate error handling for the case of
a failure to use a loopback device
has caused the Debian Bug report #503046,
regarding xen-utils-3.2-1: inadequate error handling for the case of a failure
to use a loopback device
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner at bugs.debian.org
immediately.)


-- 
503046: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=503046
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems
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