[Bug 1721788] Re: Failed to get shared "write" lock with 'qemu-img info'

[Max Reitz]

Hi,

What exactly is the problem now?  As Eric explained in comment 3, "qemu-
img info -U" is what needs to be used here.  Daniel raised the problem
of --force-share/-U being undocumented, but that’s no longer the case as
of commit a7e326df1c116e99e, which was first included in the 2.12.0
release.

Max

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1721788

Title:
  Failed to get shared "write" lock with 'qemu-img info'

Status in QEMU:
  New

Bug description:
  When running 'qemu-img info test.qcow2' while test.qcow2 is currently
  used by a Qemu process, I get the error

  qemu-img: Could not open 'test.qcow2': Failed to get shared "write"
  lock.

  Why does displaying information about a disk image need a write lock
  for the file?

  Steps to reproduce:

  qemu-img create -f qcow2 test.qcow2 10M
  qemu-system-x86_64 -nographic -drive file=test.qcow2
  qemu-img info test.qcow2

  The above was tested with Qemu version 2.10.0.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1721788/+subscriptions