[v2] wifi: ath11k: Trigger sta disconnect on hardware restart

Message ID 20221104085403.11025-1-quic_youghand@quicinc.com
State New
Headers
Series [v2] wifi: ath11k: Trigger sta disconnect on hardware restart |

Commit Message

Youghandhar Chintala Nov. 4, 2022, 8:54 a.m. UTC
  Currently after the hardware restart triggered from the driver, the
station interface connection remains intact, since a disconnect trigger
is not sent to userspace. This can lead to a problem in targets where
the wifi mac sequence is added by the firmware.

After the target restart, its wifi mac sequence number gets reset to
zero. Hence AP to which our device is connected will receive frames with
a  wifi mac sequence number jump to the past, thereby resulting in the
AP dropping all these frames, until the frame arrives with a wifi mac
sequence number which AP was expecting.

To avoid such frame drops, its better to trigger a station disconnect
upon target hardware restart which can be done with API
ieee80211_reconfig_disconnect exposed to mac80211.

The other targets are not affected by this change, since the hardware
params flag is not set.

Reported-by: kernel test robot <lkp@intel.com>

Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-00887-QCAMSLSWPLZ-1

Signed-off-by: Youghandhar Chintala <quic_youghand@quicinc.com>

---
Changes from v1:
- Added arvif declaration
---
 drivers/net/wireless/ath/ath11k/core.c | 6 ++++++
 drivers/net/wireless/ath/ath11k/hw.h   | 1 +
 drivers/net/wireless/ath/ath11k/mac.c  | 8 ++++++++
 3 files changed, 15 insertions(+)
  

Comments

Kalle Valo Nov. 4, 2022, 10:47 a.m. UTC | #1
Youghandhar Chintala <quic_youghand@quicinc.com> wrote:

> Currently after the hardware restart triggered from the driver, the
> station interface connection remains intact, since a disconnect trigger
> is not sent to userspace. This can lead to a problem in targets where
> the wifi mac sequence is added by the firmware.
> 
> After the target restart, its wifi mac sequence number gets reset to
> zero. Hence AP to which our device is connected will receive frames with
> a  wifi mac sequence number jump to the past, thereby resulting in the
> AP dropping all these frames, until the frame arrives with a wifi mac
> sequence number which AP was expecting.
> 
> To avoid such frame drops, its better to trigger a station disconnect
> upon target hardware restart which can be done with API
> ieee80211_reconfig_disconnect exposed to mac80211.
> 
> The other targets are not affected by this change, since the hardware
> params flag is not set.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> 
> Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-00887-QCAMSLSWPLZ-1
> 
> Signed-off-by: Youghandhar Chintala <quic_youghand@quicinc.com>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>

This had a new warning:

drivers/net/wireless/ath/ath11k/mac.c:8056: Blank lines aren't necessary before a close brace '}'

I fixed it in the pending branch.
  
Youghandhar Chintala Nov. 4, 2022, 10:50 a.m. UTC | #2
On 11/4/2022 4:17 PM, Kalle Valo wrote:
> Youghandhar Chintala <quic_youghand@quicinc.com> wrote:
>
>> Currently after the hardware restart triggered from the driver, the
>> station interface connection remains intact, since a disconnect trigger
>> is not sent to userspace. This can lead to a problem in targets where
>> the wifi mac sequence is added by the firmware.
>>
>> After the target restart, its wifi mac sequence number gets reset to
>> zero. Hence AP to which our device is connected will receive frames with
>> a  wifi mac sequence number jump to the past, thereby resulting in the
>> AP dropping all these frames, until the frame arrives with a wifi mac
>> sequence number which AP was expecting.
>>
>> To avoid such frame drops, its better to trigger a station disconnect
>> upon target hardware restart which can be done with API
>> ieee80211_reconfig_disconnect exposed to mac80211.
>>
>> The other targets are not affected by this change, since the hardware
>> params flag is not set.
>>
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>> Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-00887-QCAMSLSWPLZ-1
>>
>> Signed-off-by: Youghandhar Chintala <quic_youghand@quicinc.com>
>> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
> This had a new warning:
>
> drivers/net/wireless/ath/ath11k/mac.c:8056: Blank lines aren't necessary before a close brace '}'
>
> I fixed it in the pending branch.

Thank you Kalle.

Regards,

Youghandhar
  
Kalle Valo Nov. 8, 2022, 10:16 a.m. UTC | #3
Youghandhar Chintala <quic_youghand@quicinc.com> wrote:

> Currently after the hardware restart triggered from the driver, the
> station interface connection remains intact, since a disconnect trigger
> is not sent to userspace. This can lead to a problem in targets where
> the wifi mac sequence is added by the firmware.
> 
> After the target restart, its wifi mac sequence number gets reset to
> zero. Hence AP to which our device is connected will receive frames with
> a  wifi mac sequence number jump to the past, thereby resulting in the
> AP dropping all these frames, until the frame arrives with a wifi mac
> sequence number which AP was expecting.
> 
> To avoid such frame drops, its better to trigger a station disconnect
> upon target hardware restart which can be done with API
> ieee80211_reconfig_disconnect exposed to mac80211.
> 
> The other targets are not affected by this change, since the hardware
> params flag is not set.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> 
> Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-00887-QCAMSLSWPLZ-1
> 
> Signed-off-by: Youghandhar Chintala <quic_youghand@quicinc.com>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

a018750a2cce wifi: ath11k: Trigger sta disconnect on hardware restart
  

Patch

diff --git a/drivers/net/wireless/ath/ath11k/core.c b/drivers/net/wireless/ath/ath11k/core.c
index 0ab2f190f1ec..edf78df9b12f 100644
--- a/drivers/net/wireless/ath/ath11k/core.c
+++ b/drivers/net/wireless/ath/ath11k/core.c
@@ -195,6 +195,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = true,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE,
 		.smp2p_wow_exit = false,
+		.support_fw_mac_sequence = false,
 	},
 	{
 		.name = "qca6390 hw2.0",
@@ -277,6 +278,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = true,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE,
 		.smp2p_wow_exit = false,
+		.support_fw_mac_sequence = true,
 	},
 	{
 		.name = "qcn9074 hw1.0",
@@ -356,6 +358,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = true,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE,
 		.smp2p_wow_exit = false,
+		.support_fw_mac_sequence = false,
 	},
 	{
 		.name = "wcn6855 hw2.0",
@@ -438,6 +441,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = true,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE,
 		.smp2p_wow_exit = false,
+		.support_fw_mac_sequence = true,
 	},
 	{
 		.name = "wcn6855 hw2.1",
@@ -519,6 +523,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = true,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE,
 		.smp2p_wow_exit = false,
+		.support_fw_mac_sequence = true,
 	},
 	{
 		.name = "wcn6750 hw1.0",
@@ -597,6 +602,7 @@  static const struct ath11k_hw_params ath11k_hw_params[] = {
 		.tcl_ring_retry = false,
 		.tx_ring_size = DP_TCL_DATA_RING_SIZE_WCN6750,
 		.smp2p_wow_exit = true,
+		.support_fw_mac_sequence = true,
 	},
 };
 
diff --git a/drivers/net/wireless/ath/ath11k/hw.h b/drivers/net/wireless/ath/ath11k/hw.h
index 8a3f24862edc..0c5ef8a526d8 100644
--- a/drivers/net/wireless/ath/ath11k/hw.h
+++ b/drivers/net/wireless/ath/ath11k/hw.h
@@ -219,6 +219,7 @@  struct ath11k_hw_params {
 	bool tcl_ring_retry;
 	u32 tx_ring_size;
 	bool smp2p_wow_exit;
+	bool support_fw_mac_sequence;
 };
 
 struct ath11k_hw_ops {
diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index 6426a38f8961..d0ba05e7e879 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -8010,6 +8010,7 @@  ath11k_mac_op_reconfig_complete(struct ieee80211_hw *hw,
 	struct ath11k *ar = hw->priv;
 	struct ath11k_base *ab = ar->ab;
 	int recovery_count;
+	struct ath11k_vif *arvif;
 
 	if (reconfig_type != IEEE80211_RECONFIG_TYPE_RESTART)
 		return;
@@ -8045,6 +8046,13 @@  ath11k_mac_op_reconfig_complete(struct ieee80211_hw *hw,
 				ath11k_dbg(ab, ATH11K_DBG_BOOT, "reset success\n");
 			}
 		}
+		if (ar->ab->hw_params.support_fw_mac_sequence) {
+			list_for_each_entry(arvif, &ar->arvifs, list) {
+				if (arvif->is_up && arvif->vdev_type == WMI_VDEV_TYPE_STA)
+					ieee80211_hw_restart_disconnect(arvif->vif);
+			}
+		}
+
 	}
 
 	mutex_unlock(&ar->conf_mutex);