USB HID driver fails to recognize input devices

Sebastian Sumpf Sebastian.Sumpf at ...1...
Fri Jul 13 13:07:04 CEST 2012

On 07/12/2012 03:21 PM, Markus Partheymueller wrote:
> DEBUG_IRQ revealed no real news for me, except for the fact that IRQ
> 10 was discovered, but apparently no interrupt came in, handle() was
> not called once. So I added acpi_drv to my setup, resulting in a
> different log. As you suggested, I attached the new log as well as my
> configuration file. Another interesting fact is that, when the iommu
> flag of the hypervisor is removed, it looks quite different already. A
> log file of this behavior is also attached. Regards Markus
Okay the ACPI driver seems definitely necessary here. Since the device
IRQs (10/11) are overwritten (to GSI 16/18) by the driver. So far so
good, what is really weird is that the drivers seems to read strange
values in the IOMMU case.

@Alexander Boettcher: Is there anything to consider regarding I/O memory
when using Nova with enabled IOMMU?

The second example (no IOMMU) looks actually better. The strange thing
here is that the available RAM quota does not seems to suffice. Are you
on a 64Bit machine? For a quick fix you could try to increase the memory
quota of some servers until you don't get the 'Quota exceeded' message
any more. On the other hand, if this is a 64Bit machine the GSI values
produced by the ACPI driver might be wrong, since it only parses the
DSDT, on 64Bit one would have to use the XDSDT table. To make long
things short, as long as you don't get interrupts from the UHCI/EHCI
controllers the driver will not work. The thing to find out is, why we
don't get interrupts on Nova. Unfortunately I can't really help you
right now since I am pretty sick. I will test this however, when I get
my hands on a hardware box. Until then you're more than welcome to find
out what is going on.



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