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Please let > me know if I missed something below. At the moment, off the top I identified > that we are doing GFP_KERNEL memory allocations inside GPU buddy allocator > during map/unmap. I will work on solutions for that. Thanks. > > All deadlock scenarios > ---------------------- > The gist is, in the DMA fence signaling critical path we cannot acquire > resources (locks or memory allocation etc) that are already acquired when a > fence is being waited on to be signaled. So we have to careful which resources > we acquire, and also we need to be careful which paths in the driver we do any > memory allocations under locks that we need in the dma-fence signaling critical > path (when doing the virtual memory map/unmap) unmap? Are you seeing any allocations happening during unmap? I don't immediately see any, but that sounds surprising. thanks, -- John Hubbard