Bug#517449: Found in lenny 2.6.26-2-686 domU + workround?

[Berni Elbourn <berni@elbournb.fsnet.co.uk>]

I ran a stress in a Lenny 2.6.26-2-686 hvm domu as follows:

# stress --cpu 16 --io 16 --vm 16 --hdd 16 --timeout 3600

Ok its a pretty heavy test for a dual core 2Gb domain...but I got the 
same blocked task behaviour:

INFO: task stress:9878 blocked for more than 120 seconds.

Also:

hda: dma_timer_expiry: dma status == 0x24
hda: dma_timer_expiry: dma status == 0x21

The domu did reboot ok to recover.  Significantly Dom0 which is 
2.6.26-2-xen-amd64 survived unscathed.

Interesting downgrading the domu kernel to oldstable 2.6.18-5-686 the 
same stress test passed by without incident. <<< a work round?

Perhaps this may approach be a handy and quick work round for existing 
production sites until this bug is fixed in the official Lenny kernel.

Berni