From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> [ Upstream commit ce3653a8d3db096aa163fc80239d8ec1305c81fa ] The trace below can appear: [83613.832200] INFO: trying to register non-static key. [83613.837248] the code is fine but needs lockdep annotation. [83613.842808] turning off the locking correctness validator. [83613.848375] CPU: 3 PID: 141 Comm: kworker/3:2H Tainted: G O 5.6.13-silabs15 #2 [83613.857019] Hardware name: BCM2835 [83613.860605] Workqueue: events_highpri bh_work [wfx] [83613.865552] Backtrace: [83613.868041] [<c010f2cc>] (dump_backtrace) from [<c010f7b8>] (show_stack+0x20/0x24) [83613.881463] [<c010f798>] (show_stack) from [<c0d82138>] (dump_stack+0xe8/0x114) [83613.888882] [<c0d82050>] (dump_stack) from [<c01a02ec>] (register_lock_class+0x748/0x768) [83613.905035] [<c019fba4>] (register_lock_class) from [<c019da04>] (__lock_acquire+0x88/0x13dc) [83613.924192] [<c019d97c>] (__lock_acquire) from [<c019f6a4>] (lock_acquire+0xe8/0x274) [83613.942644] [<c019f5bc>] (lock_acquire) from [<c0daa5dc>] (_raw_spin_lock_irqsave+0x58/0x6c) [83613.961714] [<c0daa584>] (_raw_spin_lock_irqsave) from [<c0ab3248>] (skb_dequeue+0x24/0x78) [83613.974967] [<c0ab3224>] (skb_dequeue) from [<bf330db0>] (wfx_tx_queues_get+0x96c/0x1294 [wfx]) [83613.989728] [<bf330444>] (wfx_tx_queues_get [wfx]) from [<bf320454>] (bh_work+0x454/0x26d8 [wfx]) [83614.009337] [<bf320000>] (bh_work [wfx]) from [<c014c920>] (process_one_work+0x23c/0x7ec) [83614.028141] [<c014c6e4>] (process_one_work) from [<c014cf1c>] (worker_thread+0x4c/0x55c) [83614.046861] [<c014ced0>] (worker_thread) from [<c0154c04>] (kthread+0x138/0x168) [83614.064876] [<c0154acc>] (kthread) from [<c01010b4>] (ret_from_fork+0x14/0x20) [83614.072200] Exception stack(0xecad3fb0 to 0xecad3ff8) [83614.077323] 3fa0: 00000000 00000000 00000000 00000000 [83614.085620] 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [83614.093914] 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Indeed, the code of wfx_add_interface() shows that the interface is enabled to early. So, the spinlock associated with some skb_queue may not yet initialized when wfx_tx_queues_get() is called. Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200825085828.399505-8-Jerome.Pouiller@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/staging/wfx/sta.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/staging/wfx/sta.c b/drivers/staging/wfx/sta.c index 7dace7c17bf5c..536c62001c709 100644 --- a/drivers/staging/wfx/sta.c +++ b/drivers/staging/wfx/sta.c @@ -761,17 +761,6 @@ int wfx_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif) return -EOPNOTSUPP; } - for (i = 0; i < ARRAY_SIZE(wdev->vif); i++) { - if (!wdev->vif[i]) { - wdev->vif[i] = vif; - wvif->id = i; - break; - } - } - if (i == ARRAY_SIZE(wdev->vif)) { - mutex_unlock(&wdev->conf_mutex); - return -EOPNOTSUPP; - } // FIXME: prefer use of container_of() to get vif wvif->vif = vif; wvif->wdev = wdev; @@ -788,12 +777,22 @@ int wfx_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif) init_completion(&wvif->scan_complete); INIT_WORK(&wvif->scan_work, wfx_hw_scan_work); - mutex_unlock(&wdev->conf_mutex); + wfx_tx_queues_init(wvif); + wfx_tx_policy_init(wvif); + + for (i = 0; i < ARRAY_SIZE(wdev->vif); i++) { + if (!wdev->vif[i]) { + wdev->vif[i] = vif; + wvif->id = i; + break; + } + } + WARN(i == ARRAY_SIZE(wdev->vif), "try to instantiate more vif than supported"); hif_set_macaddr(wvif, vif->addr); - wfx_tx_queues_init(wvif); - wfx_tx_policy_init(wvif); + mutex_unlock(&wdev->conf_mutex); + wvif = NULL; while ((wvif = wvif_iterate(wdev, wvif)) != NULL) { // Combo mode does not support Block Acks. We can re-enable them @@ -825,6 +824,7 @@ void wfx_remove_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif) wvif->vif = NULL; mutex_unlock(&wdev->conf_mutex); + wvif = NULL; while ((wvif = wvif_iterate(wdev, wvif)) != NULL) { // Combo mode does not support Block Acks. We can re-enable them -- 2.27.0