On Wed, 2024-10-16 at 16:58 -0700, Kuniyuki Iwashima wrote: > > Btw, why WEXT cannot be module ? TBH, I don't remember well. I feel like I may have tried ~20 years ago, but hit issues, and just made the built-in parts minimal. Might've been we didn't have net->gen yet (did we? I don't recall), but I wouldn't be surprised if there are other issues with it as well with ioctl linkage and /proc and whatever else it does. Not sure it's worth trying, WEXT really ought to be on the way out now, and with WiFi7 (and higher) devices it's completely disabled. Btw, if you really wanted to, I suspect you _could_ use net->gen[], make the .size only a pointer size and then allocate the real data only if a wireless capable device shows up in the namespace? Then that'd actually be a win (vs. the other discussion we just had above) since wireless devices are probably almost never in a netns. Not sure you'd be able to easily free it when the last wifi capable devices leaves a netns, but that probably also doesn't matter. I don't know though how much the size of the netns matters for the scalability issue you have in mind, seems the O(N) time behaviour here is more problematic than a handful of bytes. johannes
