(In reply to Thomas Martitz from comment #21)
> 
> I assume this is some mapped memory and some HW component in the GPU writes
> to it while the CPU is using it, isn't it? If so, the proper fix would be to
> prevent that but I don't know what's the proper way of doing it in this
> context.

The CPU is writing to a buffer that the GPU ultimately reads.  Even if the data
in the buffer were corrupted by the GPU somehow, the CPU's pointer should still
be valid.  Can you add slub_debug=FPZU to the kernel command line in grub and
attach your dmesg output?