On Wed, Sep 30, 2015 at 04:52:47PM +0200, Andreas Hartmann wrote:
> > Alternativly someone who can reproduce it should trace the calls to
> > __map_single and __unmap_single in the AMD IOMMU driver to find out
> > whether the addresses which the faults happen on are really mapped, or
> > at least requested from the AMD IOMMU driver.
> 
> How can I trace it?

Please apply the attached debug patch on-top of Linux v4.3-rc3 and boot
the machine. After boot you run (as root):


	# cat /sys/kernel/debug/tracing/trace_pipe > trace-data

Please run this in a seperate shell an keep it running.

Then trigger the problem while the above command is running. When you
triggered it, please send me the (compressed) trace-data file, full
dmesg and output of lspci on the box.

Please let me know if you have further questions.


Thanks,

	Joerg