Hi,
The 7.2.12-1 upload closed this bug in unstable, but trixie still ships
linux 6.12.113-1, which has the regression. I am confirming it on another
machine and asking for the upstream stable revert to be applied to the
next trixie kernel update.
System
------
Debian GNU/Linux 13 (trixie), amd64
Board: ASUS P8H61-M LX R2.0 (EHCI USB)
2x Qualcomm Atheros AR9271 USB (0cf3:9271, bcdDevice 1.08), ath9k_htc
firmware-atheros 20250410-2
Results
-------
6.12.111-1 OK both adapters come up
6.12.113-1 FAIL on every boot (3 of 3), with FW 1.3 (htc_9271.fw) and
with FW 1.4 (htc_9271-1.4.0.fw), so this is not tied to
one firmware version:
wpa_supplicant: Could not set interface wlx6470022661e3 flags (UP):
Message too long
wpa_supplicant: nl80211: Could not set interface 'wlx6470022661e3' UP
wpa_supplicant: wlx6470022661e3: Failed to initialize driver interface
The -EMSGSIZE comes from ath9k_wmi_rsp_callback(), which 6.12.113 added
with "wifi: ath9k: reject short WMI command responses" (upstream
93ce8ea70451). AR9271 firmware sends zero-length replies to commands
that return nothing.
Fix
---
Upstream: 90201351a862 Revert "wifi: ath9k: reject short WMI command
responses"
Stable: 892422ca780a (in v6.12.114)
The revert applies cleanly to the 6.12.113 source and touches only
drivers/net/wireless/ath/ath9k/wmi.{c,h}. A patch is attached.
What I tested
-------------
1. I built ath9k_htc out of tree from the v6.12.113 sources against
linux-headers-6.12.113+deb13-amd64 without the patch. Its .text
disassembly is identical to the shipped
/lib/modules/6.12.113+deb13-amd64/.../ath9k_htc.ko, so the source
matches the Debian build.
2. With 892422ca780a applied, the module builds cleanly
(vermagic 6.12.113+deb13-amd64 SMP preempt mod_unload modversions).
3. I booted 6.12.113-1 with the patched module installed through DKMS
(/lib/modules/6.12.113+deb13-amd64/updates/dkms/ath9k_htc.ko.xz).
Both adapters probe with FW 1.4, wpa_supplicant initializes with no
"Message too long" errors (0 this boot, 24 per boot without the
patch), and NetworkManager reports "Activation: successful, device
activated" on wlxf4ec3889d79d. The revert fixes the regression on
the trixie kernel.
Attachments
-----------
0001-revert-reject-short-WMI-command-responses.patch
boot-6.12.113-fail.log (journal, failing boot)
boot-6.12.111-ok.log (journal, working boot)
boot-6.12.113-patched.log (journal, 6.12.113 + revert)
Please consider queuing 892422ca780a (or rebasing onto 6.12.114) for the
next trixie point release or security update.
Thanks,
Vinícius Fontanela
