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1. Embed this notice
   Rich Felker (dalias@hachyderm.io)'s status on Thursday, 19-Mar-2026 01:32:01 JST Rich Felker

   • William D. Jones
   • pinskia
   • disregard Joe Groff
   • nilix

   @astraleureka @r @mirabilos @cr1901 @pinskia @joe @nilix The Linux kernel docs say 4-address mode is supported whenever AP or STA mode is supported.

   https://wireless.docs.kernel.org/en/latest/en/users/documentation/iw.html#using-4-address-for-ap-and-client-mode

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Thursday, 19-Mar-2026 02:38:45 JST Rich Felker

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • Gantua
     • nilix

     @gantua @nilix @joe @r @pinskia @cr1901 @astraleureka @mirabilos Are they common? I've never encountered one and my impression was that they were a legacy thing from the very early wifi days.

   • Embed this notice
     Gantua (gantua@pleroma.marchera-pas.fr)'s status on Thursday, 19-Mar-2026 02:38:46 JST Gantua

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • nilix
     @dalias @astraleureka @r @mirabilos @cr1901 @pinskia @joe @nilix No that's not what the doc says. it says "All mac80211 drivers". mac80211 is only for softmac devices.
     
     fullmac devices (which are very common) typically do not support 4-addr mode. In fact, with a rapid grep, I could only find one fullmac driver (qtnfmac) that supports 4-addr, and only in STA mode.
   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Thursday, 19-Mar-2026 02:51:25 JST Rich Felker

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • Gantua
     • nilix

     @gantua @nilix @joe @r @pinskia @cr1901 @astraleureka @mirabilos Eew. I guess that explains why I haven't particularly noticed them still being around.

     Are they fundamentally unable to be controlled softmac or is it just a bad choice by the vendors writing drivers for them?

   • Embed this notice
     Gantua (gantua@pleroma.marchera-pas.fr)'s status on Thursday, 19-Mar-2026 02:51:27 JST Gantua

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • nilix
     @dalias @nilix @joe @r @pinskia @cr1901 @astraleureka @mirabilos You must be thinking of cfg80211, which is the common API for all modern wireless drivers. mac80211 is just a layer between cfg80211 and softmac drivers. fullmac drivers uses cfg80211 directly.
     
     Most (if not all) wireless chips found in smartphones are fullmac. The raspberry pi also uses a fullmac chipset.
   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Thursday, 19-Mar-2026 03:21:59 JST Rich Felker

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • Gantua
     • nilix

     @gantua @nilix @joe @r @pinskia @cr1901 @astraleureka @mirabilos Yes, I'm aware of all that and still deem it a gross and backwards way to do things. There's always going to be wacky/buggy device-specific behavior you can't debug, and I don't deem the advantages to be worth it.

   • Embed this notice
     Gantua (gantua@pleroma.marchera-pas.fr)'s status on Thursday, 19-Mar-2026 03:22:00 JST Gantua

     in reply to

     • William D. Jones
     • pinskia
     • disregard Joe Groff
     • nilix
     @dalias @nilix @joe @r @pinskia @cr1901 @astraleureka @mirabilos There are also laptops and even desktops motherboard with fullmac devices.
     
     All fullmac devices run a firmware that contains the equivalent of mac80211 (MLME), so if you can rewrite their firmware, you can probably turn them to softmac devices. But that's a big if, since vendors lock everything down.
     
     fullmac devices still have some advantages. They offload work off the CPU, and the CPU can even go to sleep while still connected to an AP, so the system uses less power. The offload is also useful for modern gigafast devices (think 802.11ax/be/bn) where the CPU can be a limiting factor. In fact, many modern devices are a blend of softmac and fullmac.