On Thu, Jan 10, 2019 at 10:59:02AM +0100, Michel Dänzer wrote: > > Hi Christoph, > > > https://bugs.freedesktop.org/109234 (please ignore comments #6-#9) was > bisected to your commit 55897af63091 "dma-direct: merge swiotlb_dma_ops > into the dma_direct code". Any ideas? >From the trace it looks like we git the case where swiotlb tries to copy back data from a bounce buffer, but hits a dangling or NULL pointer. So a couple questions for the submitter: - does the system have more than 4GB memory and thus use swiotlb? (check /proc/meminfo, and if something SWIOTLB appears in dmesg) - does the device this happens on have a DMA mask smaller than the available memory, that is should swiotlb be used here to start with? _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel