Guest machine freezes when NFS mount goes offline

[Igor Blanco]

I have a virtual KVM machine that has 2 CDROM units with ISOs mounted from a NFS mount point. When NFS server goes offline the virtual machine blocks completely instead of throwing read errors for the CDROM device.

Host: Proxmox VE 1.8-11 (Debian GNU/Linux 5.0)
KVM commandline version: QEMU emulator version 0.14.1 (qemu-kvm-devel)
Guest: Windows 7 professional SP 1

[Stefan Hajnoczi (stefanha)]

On Wed, Jul 27, 2011 at 10:09 AM, Igor Blanco <email address hidden> wrote:
> Public bug reported:
>
> I have a virtual KVM machine that has 2 CDROM units with ISOs mounted
> from a NFS mount point. When NFS server goes offline the virtual machine
> blocks completely instead of throwing read errors for the CDROM device.
>
> Host: Proxmox VE 1.8-11 (Debian GNU/Linux 5.0)
> KVM commandline version: QEMU emulator version 0.14.1 (qemu-kvm-devel)
> Guest: Windows 7 professional SP 1

Thanks for reporting this. There are instances where QEMU performs
blocking operations in a thread that will prevent the guest from
running. I suspect you are hitting this case and refactoring work
needs to be done to ensure that QEMU threads never block.

Stefan

[Thomas Huth (th-huth)]

Can you still reproduce this problem with the latest version of QEMU (currently version 2.9.0)?

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]