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Aleksei Sviridkin
cc96ed1e6d
The fixup set the 5 GHz phy address to the base MAC with only the locally administered bit set. The userspace VIF address allocator derives additional VIF addresses on a phy the same way: the second interface brought up on the 2.4 GHz radio gets base | 0x02, the exact value this fixup assigned to phy1. Any configuration with two VIFs on the 2.4 GHz radio (AP + mesh, AP + STA, a second AP) therefore ended up with two interfaces sharing one MAC address. Observed on a KN-3811 running an 802.11s mesh alongside the regular APs: the 2.4 GHz mesh VIF came up with the same address as the 5 GHz AP, and every batman-adv loop-avoidance announce returning from the mesh made the bridge log "received packet on bat0 with own address as source" and flap the FDB entry for that address. Simply dropping the override is not an option on these boards. Without it mt76 falls back to the second MAC slot in the calibration data (MT_EE_MAC_ADDR2, eeprom offset 0xa), but the DTS of every board here already consumes that slot as the ethernet/label address, so phy1 would collide with a wired interface instead - verified on a KN-3811, where the slot holds the WAN MAC. On KAP-630/NAP-630 that ethernet port and the 5 GHz AP even sit in the same bridge. Shifting the base is not enough either: the allocator's MBSSID scheme varies the last octet (addr[5] ^= idx), so any last-octet shift stays reachable at some index. Reproduce instead the address mt76 derives on its own when the second slot is empty: LA bit set and bit 7 of the first octet flipped. Neither allocator scheme can produce it (the default one varies bits 2-6 of octet 0, MBSSID varies octet 5), and it matches neither the base nor the base+1 ethernet address. This also gives the whole family one 5 GHz addressing convention, since boards with an empty second slot already get exactly this address from the driver. The 5 GHz BSSID of the affected boards changes accordingly. Tested on a KN-3811: phy1 comes up as the base with the LA bit and bit 7 flipped, no address overlaps on the device, and APs, mesh and clients re-associate fine. Signed-off-by: Aleksei Sviridkin <f@lex.la> Link: https://github.com/openwrt/openwrt/pull/24623 Signed-off-by: Jonas Jelonek <jonas@jonasjelonek.de>