From 3b4870dcc531c58b42a78e08f550ca89d4b4503f Mon Sep 17 00:00:00 2001 From: Sean Wang Date: Tue, 20 Jan 2026 12:10:31 -0800 Subject: [PATCH] wifi: mt76: mt7925: fix potential deadlock in mt7925_roc_abort_sync roc_abort_sync() can deadlock with roc_work(). roc_work() holds dev->mt76.mutex, while cancel_work_sync() waits for roc_work() to finish. If the caller already owns the same mutex, both sides block and no progress is possible. This deadlock can occur during station removal when mt76_sta_state() -> mt76_sta_remove() -> mt7925_mac_sta_remove_link() -> mt7925_mac_link_sta_remove() -> mt7925_roc_abort_sync() invokes cancel_work_sync() while roc_work() is still running and holding dev->mt76.mutex. This avoids the mutex deadlock and preserves exactly-once work ownership. Fixes: 45064d19fd3a ("wifi: mt76: mt7925: fix a potential association failure upon resuming") Co-developed-by: Quan Zhou Signed-off-by: Quan Zhou Signed-off-by: Sean Wang Link: https://patch.msgid.link/20260120201043.38225-2-zac@zacbowling.com Signed-off-by: Felix Fietkau --- mt7925/main.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/mt7925/main.c b/mt7925/main.c index 1fea2e80..e4376749 100644 --- a/mt7925/main.c +++ b/mt7925/main.c @@ -461,12 +461,16 @@ void mt7925_roc_abort_sync(struct mt792x_dev *dev) { struct mt792x_phy *phy = &dev->phy; + if (!test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state)) + return; + timer_delete_sync(&phy->roc_timer); - cancel_work_sync(&phy->roc_work); - if (test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state)) - ieee80211_iterate_interfaces(mt76_hw(dev), - IEEE80211_IFACE_ITER_RESUME_ALL, - mt7925_roc_iter, (void *)phy); + + cancel_work(&phy->roc_work); + + ieee80211_iterate_interfaces(mt76_hw(dev), + IEEE80211_IFACE_ITER_RESUME_ALL, + mt7925_roc_iter, (void *)phy); } EXPORT_SYMBOL_GPL(mt7925_roc_abort_sync);