[PATCH 5.19 240/717] wifi: mt76: sdio: fix the deadlock caused by sdio->stat_work

Greg Kroah-Hartman
2022-10-22T07:51:32Z

From: Sean Wang <sean.wang@mediatek.com>

[ Upstream commit e5d78fd998be94fb459a3d625df7367849b997b8 ]

Because wake_work and sdio->stat_work share the same workqueue mt76->wq,
if sdio->stat_work cannot acquire the mutex lock such as that was possibly
held up by [mt7615, mt7921]_mutex_acquire. Additionally, if
[mt7615, mt7921]_mutex_acquire was called by sdio->stat_work self, the wake
would be blocked by itself. Thus, we move the stat_work into
ieee80211_workqueue instead to break the deadlock.

Fixes: d39b52e31aa6 ("mt76: introduce mt76_sdio module")
Co-developed-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/mediatek/mt76/sdio.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/sdio.c b/drivers/net/wireless/mediatek/mt76/sdio.c
index def7f325f5c5..574687ca93a9 100644
--- a/drivers/net/wireless/mediatek/mt76/sdio.c
+++ b/drivers/net/wireless/mediatek/mt76/sdio.c
@@ -483,7 +483,7 @@ static void mt76s_status_worker(struct mt76_worker *w)
if (dev->drv->tx_status_data &&
!test_and_set_bit(MT76_READING_STATS, &dev->phy.state) &&
!test_bit(MT76_STATE_SUSPEND, &dev->phy.state))
- queue_work(dev->wq, &dev->sdio.stat_work);
+ ieee80211_queue_work(dev->hw, &dev->sdio.stat_work);
} while (nframes > 0);

if (resched)
@@ -510,7 +510,7 @@ static void mt76s_tx_status_data(struct work_struct *work)
}

if (count && test_bit(MT76_STATE_RUNNING, &dev->phy.state))
- queue_work(dev->wq, &sdio->stat_work);
+ ieee80211_queue_work(dev->hw, &sdio->stat_work);
else
clear_bit(MT76_READING_STATS, &dev->phy.state);
}
--
2.35.1