diff mbox series

Revert "wcn36xx: Enable firmware link monitoring"

Message ID 1630343360-5942-1-git-send-email-loic.poulain@linaro.org
State New
Headers show
Series Revert "wcn36xx: Enable firmware link monitoring" | expand

Commit Message

Loic Poulain Aug. 30, 2021, 5:09 p.m. UTC
This reverts commit 8def9ec46a5fafc0abcf34489a9e8a787bca984d.

The firmware keep-alive does not cause any event in case of error
such as non acked. It's just a basic keep alive to prevent the AP
to kick-off the station due to inactivity. So let mac80211 submit
its own monitoring packet (probe/null) and disconnect on timeout.

Note: We want to keep firmware keep alive to prevent kick-off
when host is in suspend-to-mem (no mac80211 monitor packet).
Ideally fw keep alive should be enabled in suspend path and disabled
in resume path to prevent having both firmware and mac80211 submitting
periodic null packets.

This fixes non detected AP leaving issues in active mode (nothing
monitors beacon or connection).

Cc: stable@vger.kernel.org
Fixes: 8def9ec46a5f ("wcn36xx: Enable firmware link monitoring")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
---
 drivers/net/wireless/ath/wcn36xx/main.c | 1 -
 1 file changed, 1 deletion(-)

Comments

Kalle Valo Aug. 31, 2021, 6:44 a.m. UTC | #1
Loic Poulain <loic.poulain@linaro.org> writes:

> This reverts commit 8def9ec46a5fafc0abcf34489a9e8a787bca984d.
>
> The firmware keep-alive does not cause any event in case of error
> such as non acked. It's just a basic keep alive to prevent the AP
> to kick-off the station due to inactivity. So let mac80211 submit
> its own monitoring packet (probe/null) and disconnect on timeout.
>
> Note: We want to keep firmware keep alive to prevent kick-off
> when host is in suspend-to-mem (no mac80211 monitor packet).
> Ideally fw keep alive should be enabled in suspend path and disabled
> in resume path to prevent having both firmware and mac80211 submitting
> periodic null packets.
>
> This fixes non detected AP leaving issues in active mode (nothing
> monitors beacon or connection).
>
> Cc: stable@vger.kernel.org
> Fixes: 8def9ec46a5f ("wcn36xx: Enable firmware link monitoring")
> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>

I'll queue this to v5.15.
Bryan O'Donoghue Aug. 31, 2021, 11:51 p.m. UTC | #2
On 31/08/2021 07:44, Kalle Valo wrote:
> Loic Poulain <loic.poulain@linaro.org> writes:
> 
>> This reverts commit wcn->hw, CONNECTION_MONITOR.
>>
>> The firmware keep-alive does not cause any event in case of error
>> such as non acked. It's just a basic keep alive to prevent the AP
>> to kick-off the station due to inactivity. So let mac80211 submit
>> its own monitoring packet (probe/null) and disconnect on timeout.
>>
>> Note: We want to keep firmware keep alive to prevent kick-off
>> when host is in suspend-to-mem (no mac80211 monitor packet).
>> Ideally fw keep alive should be enabled in suspend path and disabled
>> in resume path to prevent having both firmware and mac80211 submitting
>> periodic null packets.
>>
>> This fixes non detected AP leaving issues in active mode (nothing
>> monitors beacon or connection).
>>
>> Cc: stable@vger.kernel.org
>> Fixes: 8def9ec46a5f ("wcn36xx: Enable firmware link monitoring")
>> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> 
> I'll queue this to v5.15.
> 

Might want to hold off on that.

Its been reported by testing that wcn36xx_smd_delete_sta_context_ind() 
actually _is_ firing.

But if you look at wcn36xx_smd_delete_sta_context_ind() it doesn't seem 
to do ieee80211_connection_loss() like it presumably should.

I think the right fix here might be to call ieee80211_connection_loss() 
in wcn36xx_smd_delete_sta_context_ind() if (wcn->hw & CONNECTION_MONITOR)

---
bod
Kalle Valo Sept. 1, 2021, 6:14 a.m. UTC | #3
Bryan O'Donoghue <bryan.odonoghue@linaro.org> writes:

> On 01/09/2021 00:51, Bryan O'Donoghue wrote:
>> On 31/08/2021 07:44, Kalle Valo wrote:
>>> Loic Poulain <loic.poulain@linaro.org> writes:
>>>
>>>> This reverts commit wcn->hw, CONNECTION_MONITOR.
>>>>
>>>> The firmware keep-alive does not cause any event in case of error
>>>> such as non acked. It's just a basic keep alive to prevent the AP
>>>> to kick-off the station due to inactivity. So let mac80211 submit
>>>> its own monitoring packet (probe/null) and disconnect on timeout.
>>>>
>>>> Note: We want to keep firmware keep alive to prevent kick-off
>>>> when host is in suspend-to-mem (no mac80211 monitor packet).
>>>> Ideally fw keep alive should be enabled in suspend path and disabled
>>>> in resume path to prevent having both firmware and mac80211 submitting
>>>> periodic null packets.
>>>>
>>>> This fixes non detected AP leaving issues in active mode (nothing
>>>> monitors beacon or connection).
>>>>
>>>> Cc: stable@vger.kernel.org
>>>> Fixes: 8def9ec46a5f ("wcn36xx: Enable firmware link monitoring")
>>>> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
>>>
>>> I'll queue this to v5.15.
>>>
>>
>> Might want to hold off on that.
>>
>> Its been reported by testing that
>> wcn36xx_smd_delete_sta_context_ind() actually _is_ firing.
>>
>> But if you look at wcn36xx_smd_delete_sta_context_ind() it doesn't
>> seem to do ieee80211_connection_loss() like it presumably should.
>>
>> I think the right fix here might be to call
>> ieee80211_connection_loss() in wcn36xx_smd_delete_sta_context_ind()
>> if (wcn->hw & CONNECTION_MONITOR)
>>
>> ---
>> bod
>
> In that case right now if (wcn->hw & CONNECTION_MONITOR) we'd
> presumably rely on a subsequent wcn36xx_smd_missed_beacon_ind() but...
>
> its not clear that wcn36xx_smd_missed_beacon_ind() would fire
> subsequent to wcn36xx_smd_delete_sta_context_ind()
>
> In fact, it would be pretty illogical if it did.
>
> I think instead of revert - we want to just do better processing here
> in wcn36xx_smd_delete_sta_context_ind() alright.

Ok, I'll drop this patch.
Bryan O'Donoghue Sept. 8, 2021, 2:53 p.m. UTC | #4
On 30/08/2021 18:09, Loic Poulain wrote:
> This reverts commit 8def9ec46a5fafc0abcf34489a9e8a787bca984d.
> 
> The firmware keep-alive does not cause any event in case of error
> such as non acked. It's just a basic keep alive to prevent the AP
> to kick-off the station due to inactivity. So let mac80211 submit
> its own monitoring packet (probe/null) and disconnect on timeout.
> 
> Note: We want to keep firmware keep alive to prevent kick-off
> when host is in suspend-to-mem (no mac80211 monitor packet).
> Ideally fw keep alive should be enabled in suspend path and disabled
> in resume path to prevent having both firmware and mac80211 submitting
> periodic null packets.
> 
> This fixes non detected AP leaving issues in active mode (nothing
> monitors beacon or connection).
> 
> Cc: stable@vger.kernel.org
> Fixes: 8def9ec46a5f ("wcn36xx: Enable firmware link monitoring")
> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> ---
>   drivers/net/wireless/ath/wcn36xx/main.c | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/ath/wcn36xx/main.c b/drivers/net/wireless/ath/wcn36xx/main.c
> index 216bc34..128d25d 100644
> --- a/drivers/net/wireless/ath/wcn36xx/main.c
> +++ b/drivers/net/wireless/ath/wcn36xx/main.c
> @@ -1362,7 +1362,6 @@ static int wcn36xx_init_ieee80211(struct wcn36xx *wcn)
>   	ieee80211_hw_set(wcn->hw, HAS_RATE_CONTROL);
>   	ieee80211_hw_set(wcn->hw, SINGLE_SCAN_ON_ALL_BANDS);
>   	ieee80211_hw_set(wcn->hw, REPORTS_TX_ACK_STATUS);
> -	ieee80211_hw_set(wcn->hw, CONNECTION_MONITOR);
>   
>   	wcn->hw->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
>   		BIT(NL80211_IFTYPE_AP) |
> 

OK.

We've made a good effort to resolve offloaded link monitoring but, it 
feels like spaghetti code and isn't as reliable as letting Linux do the 
link monitoring.

Let's go ahead with the reversion.

Acked-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/wcn36xx/main.c b/drivers/net/wireless/ath/wcn36xx/main.c
index 216bc34..128d25d 100644
--- a/drivers/net/wireless/ath/wcn36xx/main.c
+++ b/drivers/net/wireless/ath/wcn36xx/main.c
@@ -1362,7 +1362,6 @@  static int wcn36xx_init_ieee80211(struct wcn36xx *wcn)
 	ieee80211_hw_set(wcn->hw, HAS_RATE_CONTROL);
 	ieee80211_hw_set(wcn->hw, SINGLE_SCAN_ON_ALL_BANDS);
 	ieee80211_hw_set(wcn->hw, REPORTS_TX_ACK_STATUS);
-	ieee80211_hw_set(wcn->hw, CONNECTION_MONITOR);
 
 	wcn->hw->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
 		BIT(NL80211_IFTYPE_AP) |