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The TODO item to eventually use XArray >>>> for recycling aux device IDs is retained, but for now, this works very >>>> nicely. >>>> >>>> This has the side effect of making debugfs[1] work on multi-GPU systems. >>> >>> Hi John, >>> >>> Looks like this is something that should be achieved via IDA? >> >> Yes, if you have no need to go from ID to pointer, an IDA is better. >> That said, as far as I understand what this code is doing, an atomic_t >> solves the problem just fine and is cheaper. > > I agree, for now an atomic should be perfectly fine. Though, with enough > patience binding/unbinding the driver from sysfs you can probably make this > overflow. :) > > The reason for the Xarray TODO is that it is one option for a place where > nova-core can store nova-drm / vGPU specific data, once either vGPU or nova-drm > attaches to the auxiliary device. But I think there may be better alternatives. OK, this seems like enough information to post a v2, thanks! thanks, -- John Hubbard