> OK, the original CentOS mirror does not make any changes to that :-( > > Is there any way I can debug these kernel panics? > The hardware I'm testing on is definetily working well (Memtest did not > find any errors, besides that, this machine is using ECC RAM) and as > mentioned, no other machine on this host throws any errors. > > > The panics seem to be a KVM related thing... > When powering up the machine, it boots without any problems. If I do a > reboot, it nevers comes up again. > Then it gets stuck in a "bootloader loop", which means, the bootloader > shows up, tries to start something and the system gets reset instantly. > The last thing I can see before the reset occurs is > "Probing EDD (edd=off to disable)... ok". > Then the machine gets reset and the bootloader comes up again. > > If I add "edd=off" to the kernel parameters before booting, it gets > stuck with a cursor in the top left corner and nothing happens - it > does'nt anything on the disks and does not consume any CPU time. > > This machine is running on a Debian Wheezy host with kernel > 3.2.0-4-amd64 and QEMU 1.1.2 / libvirtd 0.9.12. > > Is there anything I could do to debug this thing more deeply? At the > moment I have to shut off the machine when I'm going to reboot it... > > The collapsing file system has been demystified - my colleague simply > missed to reboot the systems after upgrading to the new kernel version. > But, in my opinion, that should'nt happen either... Any ext4 or kernel errors in the logs or anything at all? AFAIR there was once a problem with virtio disk drivers in C5 kvm guests.