KVM process crashes (when running Windows VMs off a specific storage)

[JTY]

proxmox-ve-2.6.32: 3.4-160 (running kernel: 2.6.32-40-pve)
pve-manager: 3.4-9 (running version: 3.4-9/4b51d87a)
pve-kernel-2.6.32-40-pve: 2.6.32-160
pve-kernel-2.6.32-39-pve: 2.6.32-157
lvm2: 2.02.98-pve4
clvm: 2.02.98-pve4
corosync-pve: 1.4.7-1
openais-pve: 1.1.4-3
libqb0: 0.11.1-2
redhat-cluster-pve: 3.2.0-2
resource-agents-pve: 3.9.2-4
fence-agents-pve: 4.0.10-3
pve-cluster: 3.0-18
qemu-server: 3.4-6
pve-firmware: 1.1-4
libpve-common-perl: 3.0-24
libpve-access-control: 3.0-16
libpve-storage-perl: 3.0-33
pve-libspice-server1: 0.12.4-3
vncterm: 1.1-8
vzctl: 4.0-1pve6
vzprocps: 2.0.11-2
vzquota: 3.1-2
pve-qemu-kvm: 2.2-11
ksm-control-daemon: 1.1-1
glusterfs-client: 3.5.2-1

Server specs:

4x E7-4820
512GB RAM
2x Intel 800GB SSDs in RAID1 (where proxmox is installed)
2x Seagate 6TB SAS in RAID1

I can install, and boot a Windows 2008R2 VM without any issues from the "local", e.g. SSD storage. However, if I move that same VM to the 6TB RAID1, the VM fails to boot. The kvm process will crash early in the boot process. Attempting to install a fresh Windows VM within the 6TB storage, also results in a crash after selecting the installation disk. Now for the other odd part, I can install and boot a Linux VM (Debian 7) from the 6TB storage without any issues.

Things I've tried:

Using VirtIO, SATA, and IDE disk modes. All fail in the same places.
Configuring the 6TB array with ext4, and setting it as directory storage.
Configuring the 6TB array as LVM.
I even tried the 3.10 kernel, which logged that KVM was having a "Segmentation fault".

Has anyone else seen this happen? I'm tempted to wipe the machine, and install 4.0 beta, to see if that behaves differently.

 

[JTY]

Interestingly enough, changing the Cache mode on the VM's disk from Default to "Write through" enables it to work. Though, I'm hoping to figure out why that is needed.

 

[JTY]

I suspect this may be related to the 6TB volume being 4K native without 512 byte emulation. Also experienced a similar crash with an old RHEL5 VM on the same RAID volume. Switched it to "Write through", and the VM was fine.