4.2.2 pci-passthrough crashes Dell Poweredge R710

[Alexander Bienzeisler <chosi@amd.co.at>]

Hello everyone,

i just updated from 4.2.1 to 4.2.2. If i try to fire up my win2k8 domU 
with a pci device attached, the dom0 machine hardcrashes.

my system log (idrac) shows the following:

CPU 2 has an internal error (IERR).
A bus fatal error was detected on a component at bus 0 device 0 function 0.
CPU 1 machine check detected.

and plenty of other entries. The machine hardresets then.
If i leave the faulty machine down after a reboot, nothing like this 
happens.

xl info:
> host                   : susi-0
> release                : 3.8.2-ipmi
> version                : #4 SMP Mon Mar 11 12:54:31 CET 2013
> machine                : x86_64
> nr_cpus                : 12
> max_cpu_id             : 31
> nr_nodes               : 2
> cores_per_socket       : 6
> threads_per_core       : 1
> cpu_mhz                : 3325
> hw_caps                : 
> bfebfbff:2c100800:00000000:00003f40:029ee3ff:00000000:00000001:00000000
> virt_caps              : hvm
> total_memory           : 98291
> free_memory            : 62390
> sharing_freed_memory   : 0
> sharing_used_memory    : 0
> free_cpus              : 0
> xen_major              : 4
> xen_minor              : 2
> xen_extra              : .2
> xen_caps               : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 
> hvm-3.0-x86_32p hvm-3.0-x86_64
> xen_scheduler          : credit
> xen_pagesize           : 4096
> platform_params        : virt_start=0xffff800000000000
> xen_changeset          : unavailable
> xen_commandline        : placeholder loglvl=all dom0_mem=2048M 
> dom0_max_vcpus=2 com2=115200 console=com2,vga
> cc_compiler            : gcc (Debian 4.4.5-8) 4.4.5
> cc_compile_by          : root
> cc_compile_domain      : wsk.tu-chemnitz.de
> cc_compile_date        : Tue May 14 09:16:43 CEST 2013
> xend_config_format     : 4