On 2/5/26 6:19 AM, Danilo Krummrich wrote:
On Thu Feb 5, 2026 at 2:48 PM CET, Matthew Wilcox wrote:
On Thu, Feb 05, 2026 at 01:44:27PM +0000, Gary Guo wrote:
Fix this by using an atomic counter to generate unique IDs for each
GPU's aux device registration. 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
