KVM: 0.179
semantic: 0.136
device: 0.111
performance: 0.108
PID: 0.084
other: 0.081
vnc: 0.059
graphic: 0.043
network: 0.041
socket: 0.034
files: 0.032
debug: 0.031
boot: 0.031
permissions: 0.030
KVM: 0.766
debug: 0.035
performance: 0.030
PID: 0.028
network: 0.022
socket: 0.021
other: 0.020
files: 0.018
device: 0.018
boot: 0.013
semantic: 0.010
vnc: 0.009
graphic: 0.004
permissions: 0.004

Guest machine freezes when NFS mount goes offline

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

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


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

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