diff options
| author | Felix Fietkau <nbd@nbd.name> | 2018-04-25 11:11:23 +0200 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2018-04-30 13:21:29 +0300 |
| commit | 1d868b70e06a2319fdda46cc46ec7c6762557543 (patch) | |
| tree | 4915b6fed8eb3edd93b3263598b9f9ea0ce1f0c5 /drivers/net | |
| parent | 9febfa67ca1566294ea5fd1f95ebf02181e7a233 (diff) | |
mt76: add rcu locking around tx scheduling
Fixes a reported lockdep error in mac80211:
[ 179.867321] =============================
[ 179.871510] WARNING: suspicious RCU usage
[ 179.875528] 4.14.32 #0 Not tainted
[ 179.878924] -----------------------------
[ 179.882981] backports-2017-11-01/net/mac80211/tx.c:594 suspicious rcu_dereference_check() usage!
[ 179.891785]
[ 179.891785] other info that might help us debug this:
[ 179.891785]
[ 179.899824]
[ 179.899824] rcu_scheduler_active = 2, debug_locks = 1
[ 179.906343] 2 locks held by ksoftirqd/0/7:
[ 179.910479] #0: (&(&q->lock)->rlock){+.-.}, at: [<86b207a4>] mt76_dma_tx_cleanup+0x64/0x354 [mt76]
[ 179.919734] #1: (&(&fq->lock)->rlock){+.-.}, at: [<87238410>] ieee80211_tx_dequeue+0x54/0xc3c [mac80211]
[ 179.929890]
[ 179.929890] stack backtrace:
[ 179.934257] CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.14.32 #0
[ 179.940421] Stack : 00000000 00000000 00000000 00000000 80e0fce2 00000036 00000000 00000000
[ 179.948864] 87c3d24c 80696377 8061039c 00000000 00000007 00000001 87c5db78 6534689d
[ 179.957306] 00000000 00000000 80e10000 87c5da74 00000001 0000015a 00000007 00000000
[ 179.965748] 00000000 806a0000 000e4171 00000000 00000000 00000000 ffffffff 00000001
[ 179.974189] 806c0000 8692b240 86b000d0 87316fe4 00000001 802c9a68 00000000 80700000
[ 179.982632] ...
[ 179.985104] Call Trace:
[ 179.987582] [<80010a48>] show_stack+0x58/0x100
[ 179.992040] [<804c2c58>] dump_stack+0xe8/0x170
[ 179.996868] [<87234a04>] ieee80211_tx_h_select_key+0xa8/0x5b8 [mac80211]
[ 180.004299] [<87238d44>] ieee80211_tx_dequeue+0x988/0xc3c [mac80211]
[ 180.011048] [<86b230dc>] mt76_txq_schedule+0x110/0x3a4 [mt76]
[ 180.016821] [<86b209d0>] mt76_dma_tx_cleanup+0x290/0x354 [mt76]
[ 180.022777] [<86be2e60>] mt7603_tx_tasklet+0x40/0x6c [mt7603e]
[ 180.028637] [<80037058>] tasklet_action+0x110/0x1ec
[ 180.033532] [<804e1dac>] __do_softirq+0x164/0x35c
[ 180.038235] [<80037174>] run_ksoftirqd+0x40/0x84
[ 180.042870] [<800580c8>] smpboot_thread_fn+0x1a8/0x1d8
[ 180.048023] [<800542e8>] kthread+0x130/0x144
[ 180.052297] [<8000b1f8>] ret_from_kernel_thread+0x14/0x1c
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/wireless/mediatek/mt76/tx.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/wireless/mediatek/mt76/tx.c b/drivers/net/wireless/mediatek/mt76/tx.c index 4eef69bd8a9e..6aca794cf998 100644 --- a/drivers/net/wireless/mediatek/mt76/tx.c +++ b/drivers/net/wireless/mediatek/mt76/tx.c @@ -422,12 +422,14 @@ void mt76_txq_schedule(struct mt76_dev *dev, struct mt76_queue *hwq) { int len; + rcu_read_lock(); do { if (hwq->swq_queued >= 4 || list_empty(&hwq->swq)) break; len = mt76_txq_schedule_list(dev, hwq); } while (len > 0); + rcu_read_unlock(); } EXPORT_SYMBOL_GPL(mt76_txq_schedule); |