From: Lorenzo Bianconi lorenzo@kernel.org
[ Upstream commit 42ce8d3b623162f3248db50a38359f294e6b06fd ]
Fix a possible race in mt7615_pm_power_save_work() if rx/tx napi schedules ps_work and we are currently accessing device register on a different cpu.
Fixes: db928f1ab9789 ("mt76: mt7663: rely on mt76_connac_pm_ref/mt76_connac_pm_unref in tx/rx napi") Signed-off-by: Lorenzo Bianconi lorenzo@kernel.org Signed-off-by: Felix Fietkau nbd@nbd.name Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/mediatek/mt76/mt7615/mac.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c index c79abce543f3..ed8f7bc18977 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c @@ -2000,6 +2000,14 @@ void mt7615_pm_power_save_work(struct work_struct *work) test_bit(MT76_HW_SCHED_SCANNING, &dev->mphy.state)) goto out;
+ if (mutex_is_locked(&dev->mt76.mutex)) + /* if mt76 mutex is held we should not put the device + * to sleep since we are currently accessing device + * register map. We need to wait for the next power_save + * trigger. + */ + goto out; + if (time_is_after_jiffies(dev->pm.last_activity + delta)) { delta = dev->pm.last_activity + delta - jiffies; goto out;