I tested the patched modules on the affected machine (Dell Precision 3650 Tower, kernel 7.0.0-31-generic, ALFA MT7921AU 0e8d:7961). Modules built out-of-tree from linux-source-7.0.0 (7.0.0-31.31) with the attached patch applied cleanly and were loaded non-persistently via insmod.
Results: 1. Unplug under active traffic (the closest reproducible approximation of my original failure): clean disconnect. The interface disappeared within seconds, nmcli / ip link / systemctl all remained responsive, and dmesg showed no call traces, no hung tasks, no "blocked for more than N seconds". On the stock driver this path is what deadlocked rtnl_lock in my original report. 2. Normal shutdown with the patched modules loaded: clean, no hang. 3. One finding: during an rmmod/insmod cycle, the teardown raced with an in-progress chip reset (mt7921u_mac_reset was running). Result: "WARNING: usb.c:578 at mt76u_complete_rx" followed by "chip reset failed". No deadlock — the driver recovered and re-initialized cleanly afterwards — but it suggests reset_work should be cancelled earlier in mt792xu_disconnect (it is currently cancelled after mac_work; if it runs, it clears MT76_RESET/MT76_MCU_RESET and a successful __mt7921_start can even re-queue mac_work). Cancelling reset_work/init_work first, or re-setting the flags after all cancellations, would close that window. I can attach the full dmesg of that WARNING if useful. Caveat: the original failure (spontaneous -110 storm followed by a USB core reset, no physical unplug) cannot be triggered on demand, so this is not a full reproduction. But the patch survives the disconnect path that previously deadlocked, and daily use plus clean shutdowns look good. Happy to test an updated patch revision or a -proposed kernel. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2167595 Title: mt7921u: USB reset after -110 timeouts deadlocks in mt7921_abort_roc, blocks rtnl_lock and shutdown To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2167595/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
