Server freezes when in Dom-0 / xen 3.2

[Florian Primessnig]

hey group,

i got a rly nasty problem here.
i got a amd64 server running ubuntu hardy LTS with latest kernel 
2.6.24-22-xen and xen 3.2 in Domain-0.

The server "freezes" randomly, by freezing i mean there is no log in 
syslog or any other log, nothing onscreen, no kernel panic, just freeze.
i cannot reproduce the system crash as it happens randomly sometime 
after a few days. only way to start the crash by force is if i try to 
get a backup of the machine via bacula-fd (a backup client). As this is 
probably a heavy I/O task maybe thats the cause of the problem.

i tried all xen versions from 3.0 to 3.2
i tried several (xen-)kernel back from 2.6.19 to 2.6.24 but the problem 
insists.

the system freeze doesnt occur if i boot up the machine in regular way 
-  not running in Xen Dom-0, so i guess it hast to be some kind of xen 
bug or misconfiguration. the raid controller i use is pretty standard, 
its even in debian and ubuntu kernel by default, so i guess a lot of ppl 
are using it and it shall not cause the problem.
RAID bus controller: 3ware Inc 7xxx/8xxx-series PATA/SATA-RAID (rev 01)

any hints ? help appreciated


regards
Florian

-- 
Florian Primessnig
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