I have found the origin of the problem for me; with feisty I had to boot using
acpi=force irqpoll
as I had suggested for instance in bug #58117
Now, the parameters to make everything work are
acpi=force pnpbios=off
irqpoll slows everything down, starting from the kernel itself (very slow boot time)
I have found the origin of the problem for me; with feisty I had to boot using
acpi=force irqpoll
as I had suggested for instance in bug #58117
Now, the parameters to make everything work are
acpi=force pnpbios=off
irqpoll slows everything down, starting from the kernel itself (very slow boot time)