Comment 37 for bug 1178707

The irqbalance problem on Xen.org sounds like the daemon crashing (which is not the case here). In the Redhat bug report it feels like people use crash when they mean hang. I remember there were some requests about backporting interrupt related patches. But due to the differences in the EC2 kernels I could not backport all of them. And then you had the same issue using the ec2 kernels and the generic kernels which have those changes.

The other bug report looks quite similar but then the mapping address is an even one, so that would be a file backed mapping. And the latest update to that report seems a problem detected while releasing pages but looks to be missing the other information. It looks to be origination from python in that case, maybe that helps a bit.

That said, when I enable function tracing on the kernel anon_vma_prepare and anon_vma_unlink functions, then irqbalance causes mappings and unmappings in a loop. Actually it happens quite a lot by other processes. But maybe if you run that as well there is something sticking out doing many of them (may increase the chance to go wrong).

as root change into /sys/kernel/debug/tracing, then
echo "anon_vma_prepare anon_vma_unlink" >set_ftrace_filter
echo function >current_tracer
cat trace_pipe | tee /tmp/ftrace.log