Description of problem:
Using a linux-based guest with KVM (tested both CentOS 6.4 and Fedora 17 guests), rebooting the guest machine causes host to completely lock up - nothing even shown in /var/log/messages. Occurred on previous kernel but waited for new kernel to check if it was still happening, however the trigger on the previous kernel was different. With previous kernel, noted that one of the components in the stack trace (which managed to display) was kms_drm, however unsure if this is also the case now as no stack trace displayed and no other information available.
Version-Release number of selected component (if applicable):
For me, every time, though it may also be hardware-related.
Steps to Reproduce:
1. Install linux-based guest in libvirt.
2. Update guest using `yum update`
3. Reboot guest
On previous kernel, occasionally the guest would boot without incident, however could induce a similar crash through the following:
1. Boot guest to runlevel 3 (with ssh running)
2. SSH to root@guest
3. `vim` .ssh/authorized_keys
Host machine freezes completely, cannot switch to terminal, cannot ssh in, no output or stack trace to screen, nothing in /var/log/messages
Host machine to remain stable and guest machine to either handle exception itself or, preferably, work correctly.
As I am unable to provide full stack trace information, I understand that it would be difficult to reproduce this bug for testing; however if it may help, I can provide hardware specifications on request.
Are you using virtio for the guests? If so, does the issue go away if you use some other network emulation, such as e1000e?
I've done some testing and the results are below. The test I was using is to boot the virtual machine, ssh in and attempt `vim .ssh/authorized_keys`. If successful, reboot the guest and attempt again. Results are:
HDD NIC Result
Virtio Virtio Fail
IDE e1000 Pass
IDE Virtio Fail
Virtio e1000 Pass
It seems that when the NIC is using a VirtIO driver, it seems to cause issues in the host's kernel...
Additional: I have two Windows 7 x86 Guests using VirtIO with the appropriate VirtIO drivers from Red Hat installed, both without issue (or at least, without related issue).
OK. I'm going to dup this bug to 975065
*** This bug has been marked as a duplicate of bug 975065 ***