Re: [6.2][regression] after commit cd372b8c99c5a5cf6a464acebb7e4a79af7ec8ae stopping working wifi mt7921e

[Felix Fietkau]

On 21.12.22 02:10, Mikhail Gavrilov wrote:
> Hi,
> The kernel 6.2 preparation cycle has begun.
> And after the kernel was updated on my laptop, the wifi stopped working.
>
> Bisecting blames this commit:
> cd372b8c99c5a5cf6a464acebb7e4a79af7ec8ae is the first bad commit
> commit cd372b8c99c5a5cf6a464acebb7e4a79af7ec8ae
> Author: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
> Date:   Sat Nov 12 16:40:35 2022 +0100
>
>      wifi: mt76: add WED RX support to mt76_dma_{add,get}_buf
>
>      Introduce the capability to configure RX WED in mt76_dma_{add,get}_buf
>      utility routines.
>
>      Tested-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
>      Co-developed-by: Sujuan Chen <sujuan.chen@xxxxxxxxxxxx>
>      Signed-off-by: Sujuan Chen <sujuan.chen@xxxxxxxxxxxx>
>      Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
>      Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
>
>   drivers/net/wireless/mediatek/mt76/dma.c  | 125 ++++++++++++++++++++----------
>   drivers/net/wireless/mediatek/mt76/mt76.h |   2 +
>   2 files changed, 88 insertions(+), 39 deletions(-)
>
> Unfortunately, I can't be sure that revert this commit will fix the
> problem. Because after the revert, compile of kernel failing with
> follow error:
> drivers/net/wireless/mediatek/mt76/mt7915/dma.c: In function ‘mt7915_dma_init’:
> drivers/net/wireless/mediatek/mt76/mt7915/dma.c:489:33: error:
> implicit declaration of function ‘MT_WED_Q_RX’; did you mean
> ‘MT_WED_Q_TX’? [-Werror=implicit-function-declaration]
>    489 |                                 MT_WED_Q_RX(MT7915_RXQ_BAND0);
>        |                                 ^~~~~~~~~~~
>        |                                 MT_WED_Q_TX
> cc1: some warnings being treated as errors
>    CC [M]  drivers/net/ethernet/intel/igb/e1000_phy.o
> make[7]: *** [scripts/Makefile.build:252:
> drivers/net/wireless/mediatek/mt76/mt7915/dma.o] Error 1
> make[7]: *** Waiting for unfinished jobs....
I'm pretty sure that commit is unrelated to this issue. However, while
looking at the code I found a bug that would explain your issue.

Please try this patch:
---
--- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
@@ -422,15 +422,15 @@ void mt7921_roc_timer(struct timer_list *timer)
 
 static int mt7921_abort_roc(struct mt7921_phy *phy, struct mt7921_vif *vif)
 {
-	int err;
-
-	if (!test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state))
-		return 0;
+	int err = 0;
 
 	del_timer_sync(&phy->roc_timer);
 	cancel_work_sync(&phy->roc_work);
-	err = mt7921_mcu_abort_roc(phy, vif, phy->roc_token_id);
-	clear_bit(MT76_STATE_ROC, &phy->mt76->state);
+
+	mt7921_mutex_acquire(phy->dev);
+	if (test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state))
+		err = mt7921_mcu_abort_roc(phy, vif, phy->roc_token_id);
+	mt7921_mutex_release(phy->dev);
 
 	return err;
 }
@@ -487,13 +487,8 @@ static int mt7921_cancel_remain_on_channel(struct ieee80211_hw *hw,
 {
 	struct mt7921_vif *mvif = (struct mt7921_vif *)vif->drv_priv;
 	struct mt7921_phy *phy = mt7921_hw_phy(hw);
-	int err;
 
-	mt7921_mutex_acquire(phy->dev);
-	err = mt7921_abort_roc(phy, mvif);
-	mt7921_mutex_release(phy->dev);
-
-	return err;
+	return mt7921_abort_roc(phy, mvif);
 }
 
 static int mt7921_set_channel(struct mt7921_phy *phy)
@@ -1778,11 +1773,8 @@ static void mt7921_mgd_complete_tx(struct ieee80211_hw *hw,
 				   struct ieee80211_prep_tx_info *info)
 {
 	struct mt7921_vif *mvif = (struct mt7921_vif *)vif->drv_priv;
-	struct mt7921_dev *dev = mt7921_hw_dev(hw);
 
-	mt7921_mutex_acquire(dev);
 	mt7921_abort_roc(mvif->phy, mvif);
-	mt7921_mutex_release(dev);
 }
 
 const struct ieee80211_ops mt7921_ops = {